All Publications

@article{pmid39625459,

title = {Daily blood flow restriction does not affect muscle fiber capillarization and satellite cell content during two weeks of bed rest in healthy young men},

author = {Thorben Aussieker and Cas J Fuchs and Antoine Zorenc and Lex B Verdijk and Luc J C van Loon and Tim Snijders},

doi = {10.1152/japplphysiol.00461.2024},

issn = {1522-1601},

year  = {2024},

date = {2024-12-01},

journal = {J Appl Physiol (1985)},

abstract = {The present study assessed whether single-leg daily blood flow restriction (BFR) treatment attenuates the decline in muscle fiber size, capillarization, and satellite cell (SC) content during 2 weeks of bed rest in healthy, young men. Twelve healthy, young men (age: 24±3 y; BMI: 23.7±3.1 kg/m) were subjected to 2 weeks of bed rest, during which one leg was exposed to three times daily 5 min of BFR, whereas the contralateral leg received sham treatment (CON). Muscle biopsies were obtained from the  from both the BFR and CON leg before and immediately after the 2 weeks of bed rest. Type I and II muscle fiber size, myonuclear content, capillarization, and SC content were assessed by immunohistochemistry. No significant decline in either type I or type II muscle fiber size were observed following bedrest, with no differences between the CON and BFR leg (>0.05). Type I muscle fiber capillary density increased in response to bed rest in both legs (<0.05), while other muscle fiber capillarization measures remained unaltered. SC content decreased in both type I (from 7.4±3.2 to 5.9±2.7 per 100 fibers) and type II (from 7.2±3.4 to 6.5±3.2 per 100 fibers) muscle fibers (main effect of time =0.018), with no significant differences between the BFR and CON leg (>0.05). In conclusion, two weeks of bed rest has no effect on muscle capillarization, decrease the SC content and daily BFR treatment does not affect skeletal muscle fiber size and SC content in healthy, young men.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Weijer2024c,

title = {Continuous glucose monitoring in para cyclists: An observational study},

author = {Vera Weijer and Rob van der Werf and Myrthe van der Haijden and Asker Jeukendrup and Luc J. C. van Loon and Jan‐Willem van Dijk},

doi = {10.1002/ejsc.12220},

issn = {1536-7290},

year  = {2024},

date = {2024-12-00},

journal = {European Journal of Sport Science},

volume = {24},

number = {12},

pages = {1809--1819},

publisher = {Wiley},

abstract = {AbstractContinuous glucose monitoring (CGM) is an emerging tool for dietary counseling in athletes. This study aimed to explore blood glucose profiles in Para cyclists and evaluate CGM accuracy at rest and during exercise. Thirteen Para cyclists, comprising eight hand bikers and five cyclists, wore a CGM sensor (Abbott) for 2 weeks. Participants recorded the timing of meals and regular training sessions and executed one standardized training session. Fifteen capillary blood glucose reference values (seven at rest and eight during the standardized training) were obtained by finger pricks. Mean glucose concentrations and time spent in hypoglycemia (<3.9 mmol/L), euglycemia (3.9–7.8 mmol/L), and hyperglycemia (>7.8 mmol/L) were calculated over 24 hrs and during daytime, nighttime, exercise, and 2 hrs postprandial periods. Mean absolute relative differences (MARD) were calculated between the CGM and capillary blood glucose. The mean glucose concentration over the 24 hr‐period was 5.7 (5.6–5.8) mmol/L. Athletes were in the euglycemia range 91% of the time. Hyperglycemia was almost exclusively observed postprandially and during exercise. Hypoglycemia was restricted to the night and was particularly observed in athletes with a spinal cord injury. CGM accuracy was acceptable at rest (MARD: 12%) but markedly lower during exercise (MARD: 34%; p = 0.01), especially for hand bikers (MARD: 41%) compared with cyclists (MARD: 24%; p = 0.01). Para cyclists generally do not display signs of disturbed glucose regulation. However, the increased risk for nocturnal hypoglycemia in athletes with a spinal cord injury warrants attention. Furthermore, CGM accuracy is compromised during exercise, especially if the sensor is in proximity to highly active muscles.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Aussieker2024c,

title = {Ingestion of a Whey Plus Collagen Protein Blend Increases Myofibrillar and Muscle Connective Protein Synthesis Rates},

author = {Thorben Aussieker and Jeremias Kaiser and Wesley J. H. Hermans and Floris K. Hendriks and Andrew M. Holwerda and Joan M. Senden and Janneau M. X. van Kranenburg and Joy P. B. Goessens and Ulrike Braun and Keith Baar and Tim Snijders and Luc J. C. van Loon},

doi = {10.1249/mss.0000000000003596},

issn = {1530-0315},

year  = {2024},

date = {2024-11-06},

publisher = {Ovid Technologies (Wolters Kluwer Health)},

abstract = {ABSTRACT

          

                           Purpose: Ingestion of whey protein increases myofibrillar but not muscle connective protein synthesis rates. Recently, we defined a whey and collagen protein blend (5:1-ratio) to optimize post-prandial plasma amino acid availability. Here, we assessed the ability of this blend to increase myofibrillar and muscle connective protein synthesis rates at rest and during early recovery from exercise.

          

                           Methods: In a randomized, double-blind, parallel design, 28 men (age: 25 ± 5 y; BMI: 23.6 ± 2.3 kg/m2) were randomly allocated to ingest either 30 g of protein (25 g whey/5 g collagen; BLEND, n = 14) or a non-caloric placebo (PLA, n = 14) following a single session of unilateral leg resistance-type exercise. Participants received primed continuous L-[ring-13C6]-phenylalanine infusions with blood and muscle biopsy samples collection for 5 hours post-prandially to assess myofibrillar and muscle connective protein synthesis rates.

          

                           Results: Protein ingestion strongly increased plasma amino acid concentrations, including plasma leucine and glycine concentrations (P < 0.001), with no changes following placebo ingestion (P > 0.05). Post-prandial myofibrillar and muscle connective protein synthesis rates were higher in the exercised compared to the rested leg (P < 0.001). In addition, myofibrillar protein synthesis rates were higher in BLEND compared to PLA in both the rested (0.038 ± 0.008 and 0.031 ± 0.006%·h−1, respectively; P < 0.05) and exercised (0.052 ± 0.011 and 0.039 ± 0.009%·h−1, respectively; P < 0.01) leg. Muscle connective protein synthesis rates were higher in BLEND compared to PLA in the rested (0.062 ± 0.013 and 0.051 ± 0.010%·h−1, respectively; P < 0.05), but not the exercised (0.090 ± 0.021 and 0.079 ± 0.016%·h−1, respectively; P = 0.11) leg.

          

                           Conclusions: Ingestion of a whey (25 g) plus collagen (5 g) protein blend increases both myofibrillar and muscle connective protein synthesis rates at rest and further increases myofibrillar but not muscle connective protein synthesis rates during recovery from exercise in recreationally active, young men.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Hilkens2024,

title = {A single bout of jumping exercise does not modulate serum markers of bone formation or bone resorption throughout a 24 h period},

author = {Luuk Hilkens and Judith Bons and Jean Nyakayiru and Luc J.C. van Loon and Jan-Willem van Dijk},

doi = {10.1016/j.bone.2024.117216},

issn = {8756-3282},

year  = {2024},

date = {2024-11-00},

journal = {Bone},

volume = {188},

publisher = {Elsevier BV},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Fuchs2024,

title = {Repeated passive heat treatment increases muscle tissue capillarization, but does not affect postprandial muscle protein synthesis rates in healthy older adults},

author = {Cas J. Fuchs and Milan W. Betz and Heather L. Petrick and Jil Weber and Joan M. Senden and Floris K. Hendriks and Julia L.M. Bels and Luc J.C. van Loon and Tim Snijders},

doi = {10.1113/jp286986},

issn = {1469-7793},

year  = {2024},

date = {2024-10-07},

journal = {The Journal of Physiology},

publisher = {Wiley},

abstract = {AbstractProlonged passive heat treatment (PHT) has been suggested to trigger skeletal muscle adaptations that may improve muscle maintenance in older individuals. To assess the effects of PHT on skeletal muscle tissue capillarization, perfusion capacity, protein synthesis rates, hypertrophy and leg strength, 14 older adults (9 males, 5 females; 73 ± 6 years) underwent 8 weeks of PHT (infrared sauna: 3× per week, 45 min at ∼60°C). Before and after PHT we collected muscle biopsies to assess skeletal muscle capillarization and fibre cross‐sectional area (CSA). Basal and postprandial muscle tissue perfusion kinetics and protein synthesis rates were assessed using contrast‐enhanced ultrasound and primed continuous l‐[ring‐13C6]phenylalanine infusions, respectively. One‐repetition maximum (1RM) leg strength and vastus lateralis muscle CSA were assessed. Type I and type II muscle fibre capillarization strongly increased following PHT (capillary‐to‐fibre perimeter exchange index: +31 ± 18 and +33 ± 30%, respectively; P < 0.001). No changes were observed in basal (0.24 ± 0.27 vs. 0.18 ± 0.11 AU; P = 0.266) or postprandial (0.20 ± 0.12 vs. 0.18 ± 0.14 AU; P = 0.717) microvascular blood flow following PHT. Basal (0.048 ± 0.014 vs. 0.051 ± 0.019%/h; P = 0.630) and postprandial (0.041 ± 0.012 vs. 0.051 ± 0.024%/h; P = 0.199) muscle protein synthesis rates did not change in response to prolonged PHT. Furthermore, no changes in vastus lateralis muscle CSA (15.3 ± 4.6 vs. 15.2 ± 4.6 cm2; P = 0.768) or 1RM leg strength (46 ± 12 vs. 47 ± 12 kg; P = 0.087) were observed over time. In conclusion, prolonged PHT increases muscle tissue capillarization but this does not improve muscle microvascular blood flow or increase muscle protein synthesis rates in healthy, older adults. Prolonged PHT does not induce skeletal muscle hypertrophy or increase leg strength in healthy, older adults.

imageKey points

Repeated exposure to heat has been suggested to trigger skeletal muscle adaptive responses.

We investigated the effect of 8 weeks of whole‐body passive heat treatment (PHT; infrared sauna: 3× per week for 45 min at ∼60°C) on skeletal muscle tissue capillarization, perfusion capacity, basal, and postprandial muscle protein synthesis rates, muscle (fibre) hypertrophy, and leg strength in healthy, older adults.

Prolonged PHT increases muscle tissue capillarization, but this does not improve muscle microvascular blood flow or increase muscle protein synthesis rates.

Despite increases in muscle tissue capillarization, prolonged PHT does not suffice to induce skeletal muscle hypertrophy or increase leg strength in healthy, older adults.

},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Houtvast2024,

title = {Underpowered Studies in Muscle Metabolism Research: Determinants and Considerations},

author = {Dion C.J. Houtvast and Milan W. Betz and Bas Van Hooren and Sophie Vanbelle and Lex B. Verdijk and Luc J.C. van Loon and Jorn Trommelen},

doi = {10.1016/j.clnesp.2024.10.152},

issn = {2405-4577},

year  = {2024},

date = {2024-10-00},

journal = {Clinical Nutrition ESPEN},

publisher = {Elsevier BV},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Holwerda2024b,

title = {Assessing Muscle Protein Synthesis Rates In Vivo in Humans: The Deuterated Water (2H2O) Method},

author = {Andrew M Holwerda and Philip J Atherton and Kenneth Smith and Daniel J Wilkinson and Stuart M Phillips and Luc JC van Loon},

doi = {10.1016/j.tjnut.2024.09.012},

issn = {0022-3166},

year  = {2024},

date = {2024-09-13},

urldate = {2024-09-00},

journal = {The Journal of Nutrition},

publisher = {Elsevier BV},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Trommelen2024b,

title = {Protein Intake Distribution: Beneficial, Detrimental, or Inconsequential for Muscle Anabolism? Response to Witard & Mettler},

author = {Jorn Trommelen and Andrew M. Holwerda and Luc J.C. van Loon},

doi = {10.1123/ijsnem.2024-0107},

issn = {1543-2742},

year  = {2024},

date = {2024-09-01},

urldate = {2024-09-01},

journal = {International Journal of Sport Nutrition and Exercise Metabolism},

volume = {34},

number = {5},

pages = {325--328},

publisher = {Human Kinetics},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Betz2024,

title = {Muscle fibre satellite cells are located at a greater distance from capillaries in patients with COPD compared with healthy controls},

author = {Milan W. Betz and Jana De Brandt and Thorben Aussieker and Alejandra P. Monsegue and Dion C.J. Houtvast and Sebastian Gehlert and Lex B. Verdijk and Luc J.C. van Loon and Harry R. Gosker and Ramon J.C. Langen and Wim Derave and Chris Burtin and Martijn A. Spruit and Tim Snijders},

doi = {10.1183/23120541.00203-2024},

issn = {2312-0541},

year  = {2024},

date = {2024-09-00},

journal = {ERJ Open Res},

volume = {10},

number = {5},

pages = {00203--2024},

publisher = {European Respiratory Society (ERS)},

abstract = {BackgroundCOPD is a disease characterised by skeletal muscle dysfunction. A spatial relationship exists between satellite cells and muscle fibre capillaries, which has been suggested to be of major importance for satellite cell function. In the present study we compared the spatial relationship between satellite cells and capillaries in patients with COPD and age-matched healthy older adults.MethodsMuscle biopsies were obtained from thevastus lateralisof n=18 patients with COPD (8 female, 10 male; age 66±5 years, mild-to-severe airflow obstruction) and n=18 age-, sex- and body mass index-matched healthy control adults (8 female, 10 male; age 68±5 years). Immunohistochemistry was used to assess type I/II muscle fibre size, distribution, myonuclear content, satellite cell number and fibre capillarisation. In addition, type I/II muscle fibre satellite cell distance to its nearest capillary was assessed.ResultsThe percentage of type II muscle fibres was significantly greater in patients with COPD (62±10%) compared with controls (50±12%, p<0.05). Muscle fibre capillarisation was significantly lower in patients with COPD compared with controls (p<0.05). While satellite cell content was not different between groups, type I and type II satellite cell distance to its nearest capillary was significantly greater in patients with COPD (type I: 21.3±4.8 µm; type II: 26.7±9.3 µm) compared with controls (type I: 16.1±3.5 µm; type II: 22.7±5.8 µm; p<0.05).ConclusionSatellite cells are located at a greater distance from their nearest capillary in patients with COPD compared with age-matched controls. This increased distance could play a role in impaired satellite cell function in patients with COPD.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Kouw2024,

title = {Short-term intermittent fasting and energy restriction do not impair rates of muscle protein synthesis: A randomised, controlled dietary intervention},

author = {Imre W.K. Kouw and Evelyn B. Parr and Michael J. Wheeler and Bridget E. Radford and Rebecca C. Hall and Joan M. Senden and Joy P.B. Goessens and Luc J.C. van Loon and John A. Hawley},

doi = {10.1016/j.clnu.2024.09.034},

issn = {0261-5614},

year  = {2024},

date = {2024-09-00},

urldate = {2024-09-00},

journal = {Clinical Nutrition},

volume = {43},

issue = {11},

pages = {174-184},

publisher = {Elsevier BV},

abstract = {Background

Intermittent fasting (IF) is an effective energy restricted dietary strategy to reduce body and fat mass and improve metabolic health in individuals with either an overweight or obese status. However, dietary energy restriction may impair muscle protein synthesis (MPS) resulting in a concomitant decline in lean body mass. Due to periods of prolonged fasting combined with irregular meal intake, we hypothesised that IF would reduce rates of MPS compared to an energy balanced diet with regular meal patterns.

Aims

We assessed the impact of a short-term (ten days) alternate day fasting or a continuous energy restricted diet to a control diet on integrated rates of skeletal MPS in middle-aged males with overweight or obesity.

Methods

Twenty-seven middle-aged males with overweight or obesity (age: 44.6±5.4 y; BMI: 30.3±2.6 kg/m2) consumed a three-day lead-in diet, followed by a ten-day controlled dietary intervention matched for protein intake, as alternate day fasting (ADF: 62.5 energy (En)%, days of 25 En% alternated with days of 100 En% food ingestion), continuous energy restriction (CER: 62.5 En%), or an energy balanced, control diet (CON: 100 En%). Deuterated water (D2O) methodology with saliva, blood, and skeletal muscle sampling were used to assess integrated rates of MPS over the ten-day intervention period. Secondary measures included fasting plasma glucose, insulin, and gastrointestinal hormone concentrations, continuous glucose monitoring, and assessment of body composition.

Results

There were no differences in daily rates of MPS between groups (ADF: 1.18±0.13, CER: 1.13±0.16, and CON: 1.18±0.18%/day, P>0.05). The reductions in body mass were greater in ADF and CER compared to CON (P<0.001). Lean and fat mass were decreased by a similar magnitude across groups (main time effect, P<0.001; main group effect, P>0.05). Fasting plasma leptin concentrations decreased in ADF and CER (P<0.001), with no differences in fasting plasma glucose or insulin concentrations between groups.

Conclusion

Short-term alternate day fasting does not lower rates of MPS compared to continuous energy restriction or an energy balanced, control diet with matched protein intake. The prolonged effects of IF and periods of irregular energy and protein intake patterns on muscle mass maintenance remain to be investigated. This trial was registered under Australian New Zealand Clinical Trial Registry (https://www.anzctr.org.au), identifier no. ACTRN12619000757112.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Schenaarts2024,

title = {A single sauna session does not improve postprandial blood glucose handling in individuals with type 2 diabetes mellitus: a cross-over, randomized, controlled trial},

author = {Laura Schenaarts and Floris K Hendriks and Cas J Fuchs and Wendy EM Sluijsmans and Tim Snijders and Luc JC van Loon},

doi = {10.1055/a-2406-4491},

issn = {1439-3646},

year  = {2024},

date = {2024-08-29},

journal = {Exp Clin Endocrinol Diabetes},

publisher = {Georg Thieme Verlag KG},

abstract = {

          Introduction Passive heat treatment has been suggested to improve glycaemic control in individuals with type 2 diabetes mellitus. Previous studies have predominantly focused on hot water immersion and traditional sauna bathing, as opposed to the more novel method of infrared-based sauna bathing. Here we assessed the impact of a single infrared sauna session on post-prandial glycaemic control in older individuals with type 2 diabetes mellitus.

Methods In this randomized controlled crossover trial, 12 participants with type 2 diabetes mellitus (male/female: 10/2, age: 69±7 y, BMI: 27.5±2.9 kg/m2) rested in an infrared sauna twice: once in a heated condition (60°C) and once in a thermoneutral condition (21°C) for 40 min, immediately followed by a 2-h oral glucose tolerance test (OGTT). Venous blood samples were obtained to assess plasma glucose and insulin concentrations and to determine the whole-body composite insulin sensitivity index.

Results Body core and leg skin temperature were higher following the heated condition compared to the thermoneutral condition (38.0±0.3 vs 36.6±0.2°C and 39.4±0.8 vs 31.3±0.8°C, respectively; P<0.001 for both). The incremental area under the curve (iAUC) of plasma glucose concentrations during the OGTT was higher after the heated condition compared to the thermoneutral condition (17.7±3.1 vs 14.8±2.8 mmol/L/120 min; \textit{P}<0.001). No differences were observed in plasma insulin concentrations (heated: 380±194 vs thermoneutral: 376±210 pmol/L/120 min; \textit{P}=0.93) or whole-body composite insulin sensitivity indexes (4.5±2.8 vs 4.5±2.1; \textit{P}=0.67).

\textbf{Conclusions} A single infrared sauna session does not improve postprandial blood glucose handling in individuals with type 2 diabetes mellitus. Future studies should assess the effect of more prolonged application of infrared sauna bathing on daily glycaemic control.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Kirmse2024,

title = {Collagen Peptide Supplementation during Training Does Not Further Increase Connective Tissue Protein Synthesis Rates},

author = {Marius Kirmse and Theo Maria Lottmann and Nicola Reiner Volk and Markus de Marées and Andrew M. Holwerda and Luc J. C. van Loon and Petra Platen},

doi = {10.1249/mss.0000000000003519},

issn = {1530-0315},

year  = {2024},

date = {2024-08-01},

publisher = {Ovid Technologies (Wolters Kluwer Health)},

abstract = {ABSTRACT

          

            Introduction

            Protein supplementation increases post-exercise muscle protein synthesis rates and, as such, supports exercise-induced muscle conditioning. Collagen protein has been suggested as the preferred protein source to stimulate muscle connective protein synthesis rates during recovery from exercise. Here we assessed the effects of hydrolyzed collagen peptide supplementation on both myofibrillar as well as muscle connective protein synthesis rates during one week of strenuous resistance exercise training.

          

          

            Methods

            In a randomized, double-blind, parallel design, 25 young men (24 ± 3 y, 76.9 ± 6.4 kg) were selected to perform one week of intense resistance-type exercise training. Subjects were randomly assigned into two groups receiving either 15 g hydrolyzed collagen peptides (COL) or a non-caloric placebo (PLA) twice daily during the intervention. Subjects were administered deuterated water (2H2O) daily, with blood and skeletal muscle tissue samples being collected prior to and after the intervention to determine daily myofibrillar and muscle connective protein synthesis rates.

          

          

            Results

            Post-absorptive plasma glycine, proline, and hydroxyproline concentrations increased following collagen peptide supplementation (p < 0.05) and showed higher levels when compared to the placebo group (p < 0.05). Daily muscle connective protein synthesis rates during the intervention period exceeded myofibrillar protein synthesis rates (1.99 ± 0.38 versus 1.34 ± 0.23 %/d, respectively; p < 0.001). Collagen peptide supplementation did not result in higher myofibrillar or muscle connective protein synthesis rates (1.34 ± 0.19 and 1.97 ± 0.47 %/d, respectively) when compared to the placebo group (1.34 ± 0.27 and 2.00 ± 0.27 %/d, respectively; p > 0.05).

          

          

            Conclusions

            Collagen peptide supplementation (2 x 15 g daily) does not increase myofibrillar or muscle connective protein synthesis rates during one week of intense resistance exercise training in young, recreational athletes.

          },

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Bels2024,

title = {Effect of high versus standard protein provision on functional recovery in people with critical illness (PRECISe): an investigator-initiated, double-blinded, multicentre, parallel-group, randomised controlled trial in Belgium and the Netherlands},

author = {Julia L M Bels and Steven Thiessen and Rob J J van Gassel and Albertus Beishuizen and Ashley De Bie Dekker and Vincent Fraipont and Stoffel Lamote and Didier Ledoux and Clarissa Scheeren and Elisabeth De Waele and Arthur R H van Zanten and Laura Bormans-Russell and Bas C T van Bussel and Marlies M J Dictus and Tom Fivez and Ingeborg Harks and Iwan C C van der Horst and Joop Jonckheer and Hugues Marechal and Paul B Massion and Ingrid Meex and Michelle C Paulus and Martin Rinket and Susanne van Santen and Katrien Tartaglia and Adam M Deane and Frieda Demuydt and Zudin Puthucheary and Lilian C M Vloet and Peter J M Weijs and Sander M J van Kuijk and Marcel C G van de Poll and Dieter Mesotten and Julia LM Bels and Bas CT van Bussel and Rob JJ van Gassel and Iwan CC van der Horst and Sander MJ van Kuijk and Marcel CG van de Poll and Susanne van Santen and Danielle van den Berk and Esther van den Hogen and Laure-Anne van Loon and Luc JC van Loon and Marlies MJ Dictus and Tom Fiez and Ingrid Meex and Dieter Mesotten and Katrien Tartaglia and Steven Thiessen and Willem Boer and Kim Engelen and Margot Vander Laenen and Xavier Willaert and Joop Jonckheer and Elisabeth De Waele and Joy Demol and Janne Geers and Marie-Claire van Malderen and Godelieve Opdenacker and Chloë Verhelst and Michelle C Paulus and Arthur RH van Zanten and Marianne Bouw-Ruiter and Imre Kouw and Max Melchers and Margreet Osinga and Yvonne Swaen-Dekkers and Ashley De Bie Dekker and Ingeborg Harks and Albertus Beishuizen and Martin Rinket and Alexander D Cornet and Tim Krol and Wytze Vermeijden and Laura Bormans-Russell and Clarissa Scheeren and Meta van der Woude and Eric Zandijk and Stoffel Lamote and Sofie Lagast and Isabel Boscart and Didier Ledoux and Paul Massion and Vincent Fraipont and Hugues Marechal and Frieda Demuydt and Lilian Vloet and Peter MJ Weijs and Zudin Puthucheary and Adam Deane},

doi = {10.1016/s0140-6736(24)01304-7},

issn = {0140-6736},

year  = {2024},

date = {2024-08-00},

journal = {The Lancet},

volume = {404},

number = {10453},

pages = {659--669},

publisher = {Elsevier BV},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Weijzen2024,

title = {Reply - Letter to the editor: Access to a pre-sleep protein snack increases daily energy and protein intake in surgical hospitalized patients},

author = {Michelle E.G. Weijzen and Luc J.C. van Loon},

doi = {10.1016/j.clnu.2024.06.032},

issn = {0261-5614},

year  = {2024},

date = {2024-08-00},

journal = {Clinical Nutrition},

volume = {43},

number = {8},

pages = {1888--1889},

publisher = {Elsevier BV},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Hengist2024,

title = {Ketogenic diet but not free-sugar restriction alters glucose tolerance, lipid metabolism, peripheral tissue phenotype, and gut microbiome: RCT},

author = {Aaron Hengist and Russell G. Davies and Jean-Philippe Walhin and Jariya Buniam and Lucy H. Merrell and Lucy Rogers and Louise Bradshaw and Alfonso Moreno-Cabañas and Peter J. Rogers and Jeff M. Brunstrom and Leanne Hodson and Luc J.C. van Loon and Wiley Barton and Ciara O’Donovan and Fiona Crispie and Orla O’Sullivan and Paul D. Cotter and Kathryn Proctor and James A. Betts and Françoise Koumanov and Dylan Thompson and Javier T. Gonzalez},

doi = {10.1016/j.xcrm.2024.101667},

issn = {2666-3791},

year  = {2024},

date = {2024-08-00},

journal = {Cell Reports Medicine},

publisher = {Elsevier BV},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Holwerda2024,

title = {Mitochondrial bioenergetics are not associated with myofibrillar protein synthesis rates},

author = {Andrew M. Holwerda and Marlou L. Dirks and Pierre‐Andre Barbeau and Joy Goessens and Annemie Gijsen and Luc J.C. van Loon and Graham P. Holloway},

doi = {10.1002/jcsm.13532},

issn = {2190-6009},

year  = {2024},

date = {2024-07-15},

journal = {J cachexia sarcopenia muscle},

publisher = {Wiley},

abstract = {AbstractBackgroundMitochondria represent key organelles influencing cellular homeostasis and have been implicated in the signalling events regulating protein synthesis.MethodsWe examined whether mitochondrial bioenergetics (oxidative phosphorylation and reactive oxygen species (H2O2) emission, ROS) measured in vitro in permeabilized muscle fibres represent regulatory factors for integrated daily muscle protein synthesis rates and skeletal muscle mass changes across the spectrum of physical activity, including free‐living and bed‐rest conditions: n = 19 healthy, young men (26 ± 4 years, 23.4 ± 3.3 kg/m2) and following 12 weeks of resistance‐type exercise training: n = 10 healthy older men (70 ± 3 years, 25.2 ± 2.1 kg/m2). Additionally, we evaluated the direct relationship between attenuated mitochondrial ROS emission and integrated daily myofibrillar and sarcoplasmic protein synthesis rates in genetically modified mice (mitochondrial‐targeted catalase, MCAT).ResultsNeither oxidative phosphorylation nor H2O2 emission were associated with muscle protein synthesis rates in healthy young men under free‐living conditions or following 1 week of bed rest (both P > 0.05). Greater increases in GSSG concentration were associated with greater skeletal muscle mass loss following bed rest (r = −0.49, P < 0.05). In older men, only submaximal mitochondrial oxidative phosphorylation (corrected for mitochondrial content) was positively associated with myofibrillar protein synthesis rates during exercise training (r = 0.72, P < 0.05). However, changes in oxidative phosphorylation and H2O2 emission were not associated with changes in skeletal muscle mass following training (both P > 0.05). Additionally, MCAT mice displayed no differences in myofibrillar (2.62 ± 0.22 vs. 2.75 ± 0.15%/day) and sarcoplasmic (3.68 ± 0.35 vs. 3.54 ± 0.35%/day) protein synthesis rates when compared with wild‐type mice (both P > 0.05).ConclusionsMitochondrial oxidative phosphorylation and reactive oxygen emission do not seem to represent key factors regulating muscle protein synthesis or muscle mass regulation across the spectrum of physical activity.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Aussieker2024,

title = {Coingestion of Collagen With Whey Protein Prevents Postexercise Decline in Plasma Glycine Availability in Recreationally Active Men},

author = {Thorben Aussieker and Tom A.H. Janssen and Wesley J.H. Hermans and Andrew M. Holwerda and Joan M. Senden and Janneau M.X. van Kranenburg and Joy P.B. Goessens and Tim Snijders and Luc J.C. van Loon},

doi = {10.1123/ijsnem.2023-0264},

issn = {1543-2742},

year  = {2024},

date = {2024-07-01},

volume = {34},

number = {4},

pages = {189--198},

publisher = {Human Kinetics},

abstract = {Whey protein ingestion during recovery from exercise increases myofibrillar but not muscle connective protein synthesis rates. It has been speculated that whey protein does not provide sufficient glycine to maximize postexercise muscle connective protein synthesis rates. In the present study, we assessed the impact of coingesting different amounts of collagen with whey protein as a nutritional strategy to increase plasma glycine availability during recovery from exercise. In a randomized, double-blind, crossover design, 14 recreationally active men (age: 26 ± 5 years; body mass index: 23.8 ± 2.1 kg·m−2) ingested in total 30 g protein, provided as whey protein with 0 g (WHEY), 5 g (WC05); 10 g (WC10), and 15 g (WC15) of collagen protein immediately after a single bout of resistance exercise. Blood samples were collected frequently over 6 hr of postexercise recovery to assess postprandial plasma amino acid kinetics and availability. Protein ingestion strongly increased plasma amino acid concentrations (p < .001) with no differences in plasma total amino acid availability between treatments (p > .05). The postprandial rise in plasma leucine and essential amino acid availability was greater in WHEY compared with the WC10 and WC15 treatments (p < .05). Plasma glycine and nonessential amino acid concentrations declined following whey protein ingestion but increased following collagen coingestion (p < .05). Postprandial plasma glycine availability averaged −8.9 ± 5.8, 9.2 ± 3.7, 23.1 ± 6.5, and 39.8 ± 11.0 mmol·360 min/L in WHEY, WC05, WC10, and WC15, respectively (incremental area under curve values, p < .05). Coingestion of a small amount of collagen (5 g) with whey protein (25 g) is sufficient to prevent the decline in plasma glycine availability during recovery from lower body resistance-type exercise in recreationally active men.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Pinckaers2024,

title = {Higher Muscle Protein Synthesis Rates Following Ingestion of an Omnivorous Meal Compared with an Isocaloric and Isonitrogenous Vegan Meal in Healthy, Older Adults},

author = {Philippe JM Pinckaers and Jacintha Domić and Heather L Petrick and Andrew M Holwerda and Jorn Trommelen and Floris K Hendriks and Lisanne HP Houben and Joy PB Goessens and Janneau MX van Kranenburg and Joan M Senden and Lisette CPGM de Groot and Lex B Verdijk and Tim Snijders and Luc JC van Loon},

doi = {10.1016/j.tjnut.2023.11.004},

issn = {0022-3166},

year  = {2024},

date = {2024-07-00},

urldate = {2024-07-00},

journal = {The Journal of Nutrition},

volume = {154},

number = {7},

pages = {2120--2132},

publisher = {Elsevier BV},

abstract = {BACKGROUND: Plant-derived proteins are considered to have lesser anabolic properties when compared with animal-derived proteins. The anabolic properties of isolated proteins do not necessarily reflect the anabolic response to the ingestion of whole-foods. The presence or absence of the various components that constitute the whole-food matrix can strongly impact protein digestion and amino acid absorption and, as such, modulate post-prandial muscle protein synthesis rates. So far, no study has compared the anabolic response following ingestion of an omnivorous versus a vegan meal. OBJECTIVE: To compare post-prandial muscle protein synthesis rates following ingestion of a whole-food meal providing 100 g lean ground beef versus an isonitrogenous, isocaloric whole-food plant-based meal in healthy, older adults. METHODS: In a randomized, counter-balanced, cross-over design, 16 older (65-85 y) adults (8 males, 8 females) underwent 2 test days. On one day, participants consumed a whole-food omnivorous meal containing beef as the primary source of protein (0.45 g protein·kg BM; MEAT). On the other day, participants consumed an isonitrogenous and isocaloric whole-food vegan meal containing unprocessed plant-based whole-foods (PLANT). Primed continuous L-[ring- C ]-phenylalanine infusions were applied with blood and muscle biopsies being collected frequently for 6 h to assess post-prandial plasma amino acid profiles and muscle protein synthesis rates. Data are presented as means±SDs and were analyzed by two way-repeated measures ANOVA and paired-samples t-tests. RESULTS: MEAT increased plasma essential amino acid concentrations more than PLANT over the 6 h post-prandial period (incremental area under curve 87±37 vs 38±54 mmol·6 h·L respectively; P-interaction<0.01). Ingestion of MEAT resulted in ~47% higher post-prandial muscle protein synthesis rates when compared to the ingestion of PLANT (0.052±0.023 and 0.035±0.021 %·h , respectively; paired-samples t-test: P=0.037). CONCLUSION: Ingestion of a whole-food meal containing beef, results in greater post-prandial muscle protein synthesis rates when compared to the ingestion of an isonitrogenous whole-food plant-based meal in older adults. https://clinicaltrials.gov/study/NCT05151887. CLINICAL TRIAL REGISTRATION: Https://clinicaltrials.gov/study/NCT05151887.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Weijer2024,

title = {Do Paralympic athletes suffer from brittle bones? Prevalence and risk factors of low bone mineral density in Paralympic athletes},

author = {Vera C.R. Weijer and Jan-Willem van Dijk and Lotte van Dam and Linn Risvang and Judith Bons and Truls Raastad and Luc J.C. van Loon and Kristin L. Jonvik},

doi = {10.1016/j.bonr.2024.101767},

issn = {2352-1872},

year  = {2024},

date = {2024-06-00},

urldate = {2024-06-00},

journal = {Bone Reports},

volume = {21},

publisher = {Elsevier BV},

abstract = {Background

Bone health may be a concern in Paralympic athletes, given the presence of multiple risk factors predisposing these athletes to low bone mineral density (BMD). Objective: We aimed to assess the prevalence of low BMD among Paralympic athletes participating in various sport disciplines, and to identify potential risk factors for low BMD.



Methods

Seventy Paralympic athletes, of whom 51 % were wheelchair-dependent, were included in this cross-sectional study. BMD of the whole-body, lumbar spine, total hip, and femoral neck were assessed by dual-energy x-ray absorptiometry. Comparisons between groups were conducted by one-way ANOVA, and regression analyses were conducted to identify potential risk factors for low BMD.



Results

The prevalence of low BMD (Z-score < −1.0) was highest at femoral neck (34 %), followed by total hip (31 %), whole-body (21 %), and lumbar spine (18 %). Wheelchair-dependent athletes had significantly lower BMD Z-scores compared to the non-wheelchair-dependent athletes at whole-body level (−0.5 ± 1.4 vs 0.2 ± 1.3; P = 0.04), total hip (−1.1 ± 1.2 vs 0.0 ± 1.1; P < 0.01), and femoral neck (−1.0 ± 1.3 vs −0.1 ± 1.2; P < 0.01). At the lumbar spine, low BMD was completely absent in wheelchair basketball and tennis players. Regression analyses identified body mass, wheelchair dependence, and type of sport, as the main risk factors for low BMD.



Conclusions

In this cohort of Paralympic athletes, low BMD is mainly present at the hip, and to a lesser extent at the whole-body and lumbar spine. The most prominent risk factors for low BMD in Paralympic athletes are related to mechanical loading patterns, including wheelchair use, the type of sport, and body mass.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Trommelen2024,

title = {Quantification and interpretation of postprandial whole-body protein metabolism using stable isotope methodology: a narrative review},

author = {Jorn Trommelen and Luc J. C. van Loon},

doi = {10.3389/fnut.2024.1391750},

issn = {2296-861X},

year  = {2024},

date = {2024-05-15},

journal = {Front. Nutr.},

volume = {11},

publisher = {Frontiers Media SA},

abstract = {Stable isotopes are routinely applied to determine the impact of factors such as aging, disease, exercise, and feeding on whole-body protein metabolism. The most common approaches to quantify whole-body protein synthesis, breakdown, and oxidation rates and net protein balance are based on the quantification of plasma amino acid kinetics. In the postabsorptive state, plasma amino acid kinetics can easily be assessed using a constant infusion of one or more stable isotope labeled amino acid tracers. In the postprandial state, there is an exogenous, dietary protein-derived amino acid flux that needs to be accounted for. To accurately quantify both endogenous as well as exogenous (protein-derived) amino acid release in the circulation, the continuous tracer infusion method should be accompanied by the ingestion of intrinsically labeled protein. However, the production of labeled protein is too expensive and labor intensive for use in more routine research studies. Alternative approaches have either assumed that 100% of exogenous amino acids are released in the circulation or applied an estimated percentage based on protein digestibility. However, such estimations can introduce large artifacts in the assessment of whole-body protein metabolism. The preferred estimation approach is based on the extrapolation of intrinsically labeled protein-derived plasma bioavailability data obtained in a similar experimental design setting. Here, we provide reference data on exogenous plasma amino acid release that can be applied to allow a more accurate routine assessment of postprandial protein metabolism. More work in this area is needed to provide a more extensive reference data set.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Monsegue2024,

title = {Resistance exercise training to improve post‐operative rehabilitation in knee arthroplasty patients: A narrative review},

author = {Alejandra P. Monsegue and Pieter Emans and Luc J. C. van Loon and Lex B. Verdijk},

doi = {10.1002/ejsc.12114},

issn = {1536-7290},

year  = {2024},

date = {2024-05-12},

journal = {European Journal of Sport Science},

publisher = {Wiley},

abstract = {AbstractKnee osteoarthritis is associated with deficits in muscle strength, muscle mass, and physical functioning. These muscle‐related deficits are acutely exacerbated following total knee arthroplasty (TKA) and persist long after surgery, despite the application of standardized rehabilitation programs that include physical/functional training. Resistance exercise training (RET) has been shown to be a highly effective strategy to improve muscle‐related outcomes in healthy as well as clinical populations. However, the use of RET in traditional rehabilitation programs after TKA is limited. In this narrative review, we provide an updated view on whether adding RET to the standard rehabilitation (SR) in the recovery period (up to 1 year) after TKA leads to greater improvements in muscle‐related outcomes when compared to SR alone. Overall, research findings clearly indicate that both muscle strength and muscle mass can be improved to a greater extent with RET‐based rehabilitation compared to SR. Additionally, measures of physical functioning that rely on quadriceps strength and balance (e.g., stair climbing, chair standing, etc.) also appear to benefit more from a RET‐based program compared to SR, especially in patients with low levels of physical functioning. Importantly though, for RET to be optimally effective, it should be performed at 70%–80% of the one‐repetition maximum, with 3–4 sets per exercise, with a minimum of 3 times per week for 8 weeks. Based upon this narrative review, we recommend that such high‐intensity progressive RET should be incorporated into standard programs during rehabilitation after TKA.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid38750012,

title = {Comparison of intramyocellular lipid metabolism in patients with diabetes and male athletes},

author = {Alice M Mezincescu and Amelia Rudd and Lesley Cheyne and Graham Horgan and Sam Philip and Donnie Cameron and Luc van Loon and Phil Whitfield and Rachael Gribbin and May Khei Hu and Mirela Delibegovic and Barbara Fielding and Gerald Lobley and Frank Thies and David E Newby and Stuart Gray and Anke Henning and Dana Dawson},

doi = {10.1038/s41467-024-47843-y},

issn = {2041-1723},

year  = {2024},

date = {2024-05-01},

urldate = {2024-05-01},

journal = {Nat Communication},

volume = {15},

number = {1},

pages = {3690},

abstract = {Despite opposing insulin sensitivity and cardiometabolic risk, both athletes and patients with type 2 diabetes have increased skeletal myocyte fat storage: the so-called "athlete's paradox". In a parallel non-randomised, non-blinded trial (NCT03065140), we characterised and compared the skeletal myocyte lipid signature of 29 male endurance athletes and 30 patients with diabetes after undergoing deconditioning or endurance training respectively. The primary outcomes were to assess intramyocellular lipid storage of the vastus lateralis in both cohorts and the secondary outcomes were to examine saturated and unsaturated intramyocellular lipid pool turnover. We show that athletes have higher intramyocellular fat saturation with very high palmitate kinetics, which is attenuated by deconditioning. In contrast, type 2 diabetes patients have higher unsaturated intramyocellular fat and blunted palmitate and linoleate kinetics but after endurance training, all were realigned with those of deconditioned athletes. Improved basal insulin sensitivity was further associated with better serum cholesterol/triglycerides, glycaemic control, physical performance, enhanced post insulin receptor pathway signalling and metabolic sensing. We conclude that insulin-resistant, maladapted intramyocellular lipid storage and turnover in patients with type 2 diabetes show reversibility after endurance training through increased contributions of the saturated intramyocellular fatty acid pools. Clinical Trial Registration: NCT03065140: Muscle Fat Compartments and Turnover as Determinant of Insulin Sensitivity (MISTY).},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid38700712,

title = {"It gave me a sense of achievement and a sense of purpose"-a qualitative study of patient experiences of a virtually supervised exercise program for adults with advanced cancer and cachexia},

author = {Kelcey A Bland and Madeleine France-Ratcliffe and Meinir Krishnasamy and Amruta Nandi and Evelyn B Parr and Peter Martin and Prue Cormie and Luc J C van Loon and Eva M Zopf},

doi = {10.1007/s00520-024-08526-y},

issn = {1433-7339},

year  = {2024},

date = {2024-05-01},

journal = {Support Care Cancer},

volume = {32},

number = {5},

pages = {325},

abstract = {People with advanced cancer and cachexia experience significant body weight loss, adversely impacting physical function and quality of life (QOL). Effective, evidence-based treatments for cancer cachexia are lacking, leaving patients with unmet needs. Exercise holds promise to improve patient QOL. However, information on patients' experiences of exercise, including their ability to cope with structured exercise, is limited.nnPURPOSE: To explore patient experiences completing a structured, supervised exercise program for people with cachexia due to advanced cancer.nnMETHODS: Semi-structured interviews were conducted with participants enrolled in a phase II feasibility, randomized controlled trial to explore their experiences of an 8-week virtually supervised exercise program delivered via videoconference technology. Interviews were analysed using reflexive thematic analysis.nnRESULTS: Seventeen participants completed interviews (female n = 9, 53%). Main interview themes included the following: (1) Deciding to exercise involves balancing concerns and expectations, (2) the exercise program is a positive experience, and (3) moving forward after the exercise program. While some participants initially held doubts about their physical capabilities and exercise safety, most wanted to exercise to enhance their wellbeing. Participants described the exercise program as a positive experience, offering diverse benefits. Some would have preferred in-person exercise, but all agreed the virtual format increased convenience. Participants emphasized the need to recommend the program to others in similar circumstances. They underscored the necessity and desire for ongoing support to sustain their new exercise habits.nnCONCLUSION: Based on patient experiences, virtually supervised exercise programming appears to be feasible and meaningful to people with advanced cancer and cachexia.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Hendriks2023,

title = {Hemodialysis does not lower circulating testosterone concentrations},

author = {Floris K. Hendriks and Jos Wiersma and Frank M. van der Sande and Sarah E. Alexander and Jeroen P. Kooman and Judith A. P. Bons and Luc J. C. van Loon},

doi = {10.1007/s40620-023-01810-w},

issn = {1724-6059},

year  = {2024},

date = {2024-05-00},

journal = {J Nephrol},

volume = {37},

number = {4},

pages = {1125--1127},

publisher = {Springer Science and Business Media LLC},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Weijer2024b,

title = {Measured and predicted resting metabolic rate of Dutch and Norwegian Paralympic athletes.},

author = {Vera C.R. Weijer and Kristin L. Jonvik and Lotte van Dam and Linn Risvang and Truls Raastad and Luc J.C. van Loon and Jan-Willem van Dijk},

doi = {10.1016/j.jand.2024.05.010},

issn = {2212-2672},

year  = {2024},

date = {2024-05-00},

journal = {Journal of the Academy of Nutrition and Dietetics},

publisher = {Elsevier BV},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Weijzen2024b,

title = {Access to a pre-sleep protein snack increases daily energy and protein intake in surgical hospitalized patients},

author = {Michelle E.G. Weijzen and Maxime Kohlen and Alejandra Monsegue and Dion C.J. Houtvast and Jean Nyakayiru and Sandra Beijer and Phil Geerlings and Lex B. Verdijk and Luc J.C. van Loon},

doi = {10.1016/j.clnu.2024.03.016},

issn = {0261-5614},

year  = {2024},

date = {2024-05-00},

urldate = {2024-05-00},

journal = {Clinical Nutrition},

volume = {43},

number = {5},

pages = {1073--1078},

publisher = {Elsevier BV},

abstract = {Background & aim: In hospitalized patients, daily protein intake remains far below WHO requirements for healthy adults (0.8 g·kg-1·d-1) as well as ESPEN guidelines for patients (1.2–1.5 g·kg-1·d-1). Providing access to a pre-sleep protein dense snack between dinner and going to bed may serve as a great opportunity to increase daily energy and protein intake in hospitalized patients. However, it remains to be assessed whether protein provision prior to sleep effectively increases protein intake, or may reduce food intake throughout the remainder of the day(s). The present study evaluated the impact of giving access to a pre-sleep snack on daily energy and protein intake in patients throughout their hospitalization. Methods: Patients admitted to the surgical wards of the Maastricht University Medical Centre+ were randomly allocated to usual care (n = 51) or given access to a pre-sleep snack (n = 50). The pre-sleep snack consisted of 103 g cheese cubes (30 g protein) provided between 7:30 and 9:30 PM, prior to sleep. All food provided and all food consumed was weighed and recorded throughout (2–7 days) hospitalization. Daily energy and protein intake and distribution were calculated. Data were analyzed by independent T-Tests with P < 0.05 considered as statistically significant. Results: Daily energy intake was higher in the pre-sleep group (1353 ± 424 kcal d-1) when compared to the usual care group (1190 ± 402 kcal·d-1; P = 0.049). Providing patients access to a pre-sleep snack resulted in a 17% (11 ± 9 g) higher daily protein intake (0.81 ± 0.29 g·kg-1·d-1) when compared to the usual care group (0.69 ± 0.28 g·kg-1·d-1; P = 0.045). Protein intake at breakfast, lunch, and dinner did not differ between the pre-sleep and usual care groups (all P > 0.05). Conclusion: Providing access to a pre-sleep protein snack, in the form of protein dense food items such as cheese, represents an effective dietary strategy to increase daily energy and protein intake in hospitalized patients. Patients consuming pre-sleep protein snacks do not compensate by lowering energy or protein intake throughout the remainder of the days. Pre-sleep protein dense food provision should be implemented in hospital food logistics to improve the nutritional intake of patients. Trial register no: NL8507 (https://trialsearch.who.int/)},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid37994085b,

title = {One Week of Single-Leg Immobilization Lowers Muscle Connective Protein Synthesis Rates in Healthy, Young Adults},

author = {Andrew M Holwerda and Michelle E G Weijzen and Antoine Zorenc and Joan Senden and Guus H J Jetten and Lisanne H P Houben and Lex B Verdijk and Luc J C VAN Loon},

doi = {10.1249/MSS.0000000000003342},

issn = {1530-0315},

year  = {2024},

date = {2024-04-01},

urldate = {2024-04-01},

journal = {Med Sci Sports Exerc},

volume = {56},

number = {4},

pages = {612--622},

abstract = {PURPOSE: Short periods of limb immobilization lower myofibrillar protein synthesis rates. Within skeletal muscle, the extracellular matrix of connective proteins is recognized as an important factor determining the capacity to transmit contractile force. Little is known regarding the impact of immobilization and subsequent recovery on muscle connective protein synthesis rates. This study examined the impact of 1 wk of leg immobilization and 2 wk of subsequent ambulant recovery on daily muscle connective protein synthesis rates. METHODS: Thirty healthy, young (24 ± 5 yr) men were subjected to 7 d of one-legged knee immobilization followed by 14 d of ambulant recovery. Deuterium oxide ingestion was applied over the entire period, and muscle biopsy samples were collected before immobilization, after immobilization, and after recovery to measure muscle connective protein synthesis rates and mRNA expression of key extracellular matrix proteins (collagen I, collagen III), glycoproteins (fibronectin, tenascin-C), and proteoglycans (fibromodulin, and decorin). A two-way repeated-measures (time-leg) ANOVA was used to compare changes in muscle connective protein synthesis rates during immobilization and recovery. RESULTS: During immobilization, muscle connective protein synthesis rates were lower in the immobilized (1.07 ± 0.30%·d -1 ) compared with the nonimmobilized (1.48 ± 0.44%·d -1 ; P < 0.01) leg. When compared with the immobilization period, connective protein synthesis rates in the immobilized leg increased during subsequent recovery (1.48 ± 0.64%·d -1 ; P < 0.01). After recovery, skeletal muscle collagen I, collagen III, fibronectin, fibromodulin, and decorin mRNA expression increased when compared with the postimmobilization time point (all P < 0.001). CONCLUSIONS: One week of leg immobilization lowers muscle connective protein synthesis rates. Muscle connective protein synthesis rates increase during subsequent ambulant recovery, which is accompanied by increased mRNA expression of key extracellular matrix proteins.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid38079310b,

title = {A Low or High Physical Activity Level Does Not Modulate Prostate Tumor Tissue Protein Synthesis Rates},

author = {Lisanne H P Houben and Tom Tuytten and Andrew M Holwerda and Erika Wisanto and Joan Senden and Will K W H Wodzig and Steven W M Olde Damink and Milou Beelen and Sandra Beijer and Koenraad VAN Renterghem and Luc J C VAN Loon},

doi = {10.1249/MSS.0000000000003349},

issn = {1530-0315},

year  = {2024},

date = {2024-04-01},

journal = {Med Sci Sports Exerc},

volume = {56},

number = {4},

pages = {635--643},

abstract = {INTRODUCTION: Physical activity level has been identified as an important factor in the development and progression of various types of cancer. In this study, we determined the impact of a low versus high physical activity level on skeletal muscle, healthy prostate, and prostate tumor protein synthesis rates in vivo in prostate cancer patients.nnMETHODS: Thirty prostate cancer patients (age, 66 ± 5 yr; body mass index, 27.4 ± 2.9 kg·m -2 ) were randomized to a low (<4000 steps per day, n = 15) or high (>14,000 steps per day, n = 15) physical activity level for 7 d before their scheduled radical prostatectomy. Daily deuterium oxide administration was combined with the collection of plasma, skeletal muscle, nontumorous prostate, and prostate tumor tissue during the surgical procedure to determine tissue protein synthesis rates throughout the intervention period.nnRESULTS: Daily step counts averaged 3610 ± 878 and 17,589 ± 4680 steps in patients subjected to the low and high physical activity levels, respectively ( P < 0.001). No differences were observed between tissue protein synthesis rates of skeletal muscle, healthy prostate, or prostate tumor between the low (1.47% ± 0.21%, 2.74% ± 0.70%, and 4.76% ± 1.23% per day, respectively) and high (1.42% ± 0.16%, 2.64% ± 0.58%, and 4.72% ± 0.80% per day, respectively) physical activity group (all P > 0.4). Tissue protein synthesis rates were nearly twofold higher in prostate tumor compared with nontumorous prostate tissue.nnCONCLUSIONS: A short-term high or low physical activity level does not modulate prostate or prostate tumor protein synthesis rates in vivo in prostate cancer patients. More studies on the impact of physical activity level on tumor protein synthesis rates and tumor progression are warranted to understand the potential impact of lifestyle interventions in the prevention and treatment of cancer.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid38228945b,

title = {Post-prandial muscle protein synthesis rates following the ingestion of pea-derived protein do not differ from ingesting an equivalent amount of milk-derived protein in healthy, young males},

author = {Philippe J M Pinckaers and Joey S J Smeets and Imre W K Kouw and Joy P B Goessens and Annemarie P B Gijsen and Lisette C P G M de Groot and Lex B Verdijk and Luc J C van Loon and Tim Snijders},

doi = {10.1007/s00394-023-03295-6},

issn = {1436-6215},

year  = {2024},

date = {2024-04-01},

journal = {Eur J Nutr},

volume = {63},

number = {3},

pages = {893--904},

abstract = {PURPOSE: Plant-derived proteins have received considerable attention as an alternative to animal-derived proteins. However, plant-derived proteins are considered to have less anabolic properties when compared with animal-derived proteins. The lower muscle protein synthesis rates following ingestion of plant- compared with animal-derived protein have been attributed to the lower essential amino acid content of plant-derived proteins and/or their specific amino acid deficiencies. This study aimed to compare post-prandial muscle protein synthesis rates following the ingestion of 30 g pea-derived protein with 30 g milk-derived protein in healthy, young males.nnMETHODS: In a randomized, double-blind, parallel-group design, 24 young males (24 ± 3 y) received a primed continuous L-[ring-C]-phenylalanine infusion after which they ingested 30 g pea (PEA) or 30 g milk-derived protein (MILK). Blood and muscle biopsies were collected frequently for 5 h to assess post-prandial plasma amino acid profiles and subsequent post-prandial muscle protein synthesis rates.nnRESULTS: MILK increased plasma essential amino acid concentrations more than PEA over the 5 h post-prandial period (incremental area under curve 151 ± 31 vs 102 ± 15 mmol∙300 min∙L, respectively; P < 0.001). Ingestion of both MILK and PEA showed a robust muscle protein synthetic response with no significant differences between treatments (0.053 ± 0.013 and 0.053 ± 0.017%∙h, respectively; P = 0.96).nnCONCLUSION: Post-prandial muscle protein synthesis rates following the ingestion of 30 g pea-derived protein do not differ from the response following ingestion of an equivalent amount of milk-derived protein. International Clinical Trials Registry Platform (NTR6548; 27-06-2017).},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid38048764b,

title = {Resistance Exercise Training, a Simple Intervention to Preserve Muscle Mass and Strength in Prostate Cancer Patients on Androgen Deprivation Therapy},

author = {Lisanne H P Houben and Milou Beelen and Luc J C van Loon and Sandra Beijer},

doi = {10.1123/ijsnem.2023-0075},

issn = {1543-2742},

year  = {2024},

date = {2024-03-01},

journal = {Int J Sport Nutr Exerc Metab},

volume = {34},

number = {2},

pages = {122--134},

abstract = {Androgen deprivation therapy (ADT) forms the cornerstone in the treatment of advanced prostate cancer. However, by suppressing testosterone ADT results in a decrease of skeletal muscle mass. In this narrative review, we explore the magnitude and mechanisms of ADT-induced muscle mass loss and the consequences for muscle strength and physical performance. Subsequently, we elucidate the effectiveness of supervised resistance exercise training as a means to mitigate these adverse effects. Literature shows that resistance exercise training can effectively counteract ADT-induced loss of appendicular lean body mass and decline in muscle strength, while the effect on physical performances is inconclusive. As resistance exercise training is feasible and can be safely implemented during ADT (with special attention for patients with bone metastases), it should be incorporated in standard clinical care for prostate cancer patients (starting) with ADT.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid38458181b,

title = {Becoming a World Champion Powerlifter at 71 Years of Age: It Is Never Too Late to Start Exercising},

author = {Cas J Fuchs and Jorn Trommelen and Michelle E G Weijzen and Joey S J Smeets and Janneau van Kranenburg and Lex B Verdijk and Luc J C van Loon},

doi = {10.1123/ijsnem.2023-0230},

issn = {1543-2742},

year  = {2024},

date = {2024-03-01},

journal = {Int J Sport Nutr Exerc Metab},

pages = {1--9},

abstract = {This case study assessed body composition, muscle strength, cardiorespiratory fitness, and metabolic health of the present female world champion powerlifter in the 70+ age category who started resistance exercise training at 63 years of age with no prior experience with structured exercise training. Measures of body composition (magnetic resonance imaging, computed tomography, and dual-energy X-ray absorptiometry scanning, leg volume); strength (one-repetition maximum leg press and extension, maximum voluntary contraction, and handgrip strength); physical function (short physical performance battery); cardiorespiratory fitness (peak oxygen consumption); and metabolic health (oral glucose tolerance test) were assessed. In addition, a muscle biopsy was collected to assess muscle fiber type distribution and cross-sectional area (CSA). Where possible, data were compared with previously (un)published sex- and age-matched data using z scores. Skeletal muscle mass index was calculated by dividing limb muscle mass by height squared. Data from the control groups are expressed as mean ± 95% confidence interval. Our participant (age: 71 years; body mass: 64.5 kg; body mass index: 27.6 kg/m2) reported a good bone mineral density of 1.09 g/cm2 (T score between -1 and +1) and very low values of abdominal and organ body fat (i.e., between 20% and 70% lower compared with a reference group of postmenopausal women). In addition, she showed a 33% greater skeletal muscle mass index when compared with healthy, older female control subjects (7.9 vs. 5.9 [5.7-6.2] kg/m2; n = 61) as well as 37% greater muscle quadriceps CSA (63.8 vs. 46.6 [44.5-48.7] cm2; n = 48) and 46% greater Type II muscle fiber CSA (4,536 vs. 3,097 [2,707-3,488] μm2; n = 19). Absolute leg press muscle strength was 36% greater (190 vs. 140 [132-147] kg; n = 30) and handgrip strength was 33% greater (33 vs. 25 [23-26] kg; n = 48) when compared with healthy, age-matched controls. In conclusion, even for resistance exercise naïve individuals, starting exercise at an advanced age can lead to improvements in body composition and muscle strength allowing older adults to reduce the risk for developing metabolic syndrome, live independently, and even compete at a world class level.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{558db45a644c44b8896d7f4ae2c76f8f,

title = {Energy expenditure and dietary intake in professional female football players in the Dutch Women's League: Implications for nutritional counselling},

author = {Naomi Brinkmans and Guy Plasqui and Luc Loon and Jan-Willem Dijk},

doi = {10.1080/02640414.2024.2329850},

issn = {0264-0414},

year  = {2024},

date = {2024-02-01},

journal = {Journal of Sports Sciences},

volume = {42},

issue = {4},

pages = {313-322},

publisher = {Routledge/Taylor & Francis Group},

abstract = {In contrast to male football players, research on the nutritional requirements of female football players is limited. This study aimed to assess total daily energy expenditure (TDEE) in professional female football players, along with body composition, physical activity and dietary intake. This observational study included 15 professional football players playing in the highest Dutch Women's League. TDEE was assessed by doubly labelled water over 14 days, along with resting metabolic rate (RMR; ventilated hood), fat-free mass (FFM; dual-energy x-ray absorptiometry), and dietary intake (24-h recalls). Physical activity energy expenditure (PAEE) was derived from subtracting RMR and estimated diet-induced thermogenesis (10%) from TDEE. TDEE was 2882 +/- 278 kcal/day (58 +/- 5 kcal/kg FFM) and significantly (p < 0.05) correlated with FFM (r = 0.62). PAEE was 1207 +/- 213 kcal/d. Weighted energy intake was 2344 kcal [2023-2589]. Carbohydrate intakes were 3.2 +/- 0.7, 4.4 +/- 1.1 and 5.3 +/- 1.9 g/kg body mass for rest, training and match days, respectively, while weighted mean protein intake was 1.9 +/- 0.4 g/kg body mass. In conclusion, the energy requirements of professional female football players are moderate to high and can be explained by the substantial PAEE. To fuel these requirements, sports nutritionists should consider shifting the players' focus towards prioritizing adequate carbohydrate intakes, rather than emphasizing high protein consumption.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{62b7e59ed094498ca94ba82b466924c3,

title = {Graded Replacement of Carbohydrate-Rich Breakfast Products with Dairy Products: Effects on Postprandial Aminoacidemia, Glycemic Control, Bone Metabolism, and Satiety},

author = {Luuk Hilkens and Floor Praster and Jan Overdam and Jean Nyakayiru and Cécile M Singh-Povel and Judith Bons and Luc Jc Loon and Jan-Willem Dijk},

doi = {10.1016/j.tjnut.2023.12.012},

issn = {0022-3166},

year  = {2024},

date = {2024-02-01},

journal = {Journal of Nutrition},

volume = {154},

number = {2},

pages = {479–490},

publisher = {Oxford University Press},

abstract = {Background: Postprandial metabolic responses following dairy consumption have mostly been studied using stand-alone dairy products or milk-derived nutrients. Objective: Assessing the impact of ingesting dairy products as part of a common breakfast on postprandial aminoacidemia, glycemic control, markers of bone metabolism, and satiety. Methods: In this randomized, crossover study, 20 healthy young males and females consumed on 3 separate occasions an iso-energetic breakfast containing no dairy (NO-D), 1 dairy (ONE-D), or 2 dairy (TWO-D) products. Postprandial concentrations of amino acids, glucose, insulin, glucagon-like peptide-1 (GLP-1), calcium, parathyroid hormone (PTH), and markers of bone formation (P1NP) and resorption (CTX-I) were measured before and up to 300 min after initiating the breakfast, along with VAS-scales to assess satiety. Results: Plasma essential and branched-chained amino acids availability (expressed as total area under the curve (tAUC)) increased in a dose-dependent manner (P<0.05 for all comparisons). Plasma glucose tAUCs were lower in ONE-D and TWO-D compared with NO-D (P<0.05 for both comparisons). Plasma GLP-1 tAUC increased in a dose-dependent manner (P<0.05 for all comparisons), whereas no differences were observed in plasma insulin tAUC between conditions (P>0.05 for all comparisons). Serum calcium tAUCs were higher in ONE-D and TWO-D compared with NO-D (P<0.05 for both comparisons), along with lower PTH tAUCs in ONE-D and TWO-D compared with NO-D (P=0.001 for both comparisons). In accordance, serum CTX-I concentrations were lower in the late postprandial period in ONE-D and TWO-D compared with NO-D (P<0.01 for both comparisons). No differences were observed in P1NP tAUCs between conditions (P>0.05). The tAUC for satiety was higher in TWO-D compared with NO-D and ONE-D (P<0.05 for both comparisons). Conclusions: Iso-energetic replacement of a carbohydrate-rich breakfast component with one serving of dairy improves postprandial amino acid availability, glycemic control, and bone metabolism. Adding a second serving of dairy in lieu of carbohydrates augments postprandial amino acid and GLP-1 concentrations while further promoting satiety. This study was registered at https://doi.org/10.1186/ISRCTN13531586 with Clinical Trial Registry number ISRCTN13531586.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid38103646,

title = {Administration of Free Amino Acids Improves Exogenous Amino Acid Availability when Compared with Intact Protein in Critically Ill Patients: A Randomized Controlled Study},

author = {Rob Jj van Gassel and Michelle Eg Weijzen and Imre Wk Kouw and Joan Mg Senden and Will Khw Wodzig and Steven Wm Olde Damink and Marcel Cg van de Poll and Luc Jc van Loon},

doi = {10.1016/j.tjnut.2023.12.015},

issn = {1541-6100},

year  = {2024},

date = {2024-02-01},

journal = {J Nutr},

volume = {154},

number = {2},

pages = {554--564},

abstract = {BACKGROUND: Protein digestion and amino acid absorption appear compromised in critical illness. The provision of enteral feeds with free amino acids rather than intact protein may improve postprandial amino acid availability.nnOBJECTIVE: Our objective was to quantify the uptake of diet-derived phenylalanine after the enteral administration of intact protein compared with an equivalent amount of free amino acids in critically ill patients.nnMETHODS: Sixteen patients who were mechanically ventilated in intensive care unit (ICU) at risk of malabsorption received a primed continuous infusion of L-[ring-H]-phenylalanine and L-[ring-3,5-H]-tyrosine after an overnight fast. Patients were randomly allocated to receive 20 g intrinsically L-[1-C]-phenylalanine-labeled milk protein or an equivalent amount of amino acids labeled with free L-[1-C]-phenylalanine via a nasogastric tube over a 2-h period. Protein digestion and amino acid absorption kinetics and whole-body protein net balance were assessed throughout a 6-h period.nnRESULTS: After enteral nutrient infusion, both plasma phenylalanine and leucine concentrations increased (P-time < 0.001), with a more rapid and greater rise after free amino acid compared with intact protein administration (P-time × treatment = 0.003). Diet-derived phenylalanine released into the circulation was 25% greater after free amino acids compared with intact protein administration [68.7% (confidence interval {CI}: 62.3, 75.1%) compared with 43.8% (CI: 32.4, 55.2%), respectively; P < 0.001]. Whole-body protein net balance became positive after nutrient administration (P-time < 0.001) and tended to be more positive after free amino acid in provision (P-time × treatment = 0.07).nnCONCLUSIONS: The administration of free amino acids as opposed to intact protein further increases postprandial plasma amino acid availability in critically ill patients, allowing more diet-derived phenylalanine to become available to peripheral tissues. This trial was registered at clinicaltrials.gov as NCT04791774.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid38315260b,

title = {The muscle protein synthetic response following corn protein ingestion does not differ from milk protein in healthy, young adults},

author = {Philippe J M Pinckaers and Michelle E G Weijzen and Lisanne H P Houben and Antoine H Zorenc and Imre W K Kouw and Lisette C P G M de Groot and Lex B Verdijk and Tim Snijders and Luc J C van Loon},

doi = {10.1007/s00726-023-03377-z},

issn = {1438-2199},

year  = {2024},

date = {2024-02-01},

journal = {Amino Acids},

volume = {56},

number = {1},

pages = {8},

abstract = {Plant-derived proteins are generally believed to possess lesser anabolic properties when compared with animal-derived proteins. This is, at least partly, attributed to the lower leucine content of most plant-derived proteins. Corn protein has a leucine content that is highest among most plant-derived proteins and it even exceeds the levels observed in animal-derived proteins such as whey protein. Therefore, this study aimed to compare muscle protein synthesis rates following the ingestion of 30 g corn protein and a 30 g blend of corn plus milk protein with 30 g milk protein. In a randomized, double blind, parallel-group design, 36 healthy young males (26 ± 4 y) received primed continuous L-[ring-C]-phenylalanine infusions and ingested 30 g corn protein (CORN), 30 g milk protein (MILK), or a 30 g proteinblend with 15 g corn plus 15 g milk protein (CORN + MILK). Blood and muscle biopsies were collected for 5 h following protein ingestion to assess post-prandial plasma amino acid profiles and myofibrillar protein synthesis rates. The results show that Ingestion of protein increased myofibrillar protein synthesis rates from basal post-absorptive values in all treatments(P < 0.001). Post-prandial myofibrillar protein synthesis rates did not differ between CORN vs MILK (0.053 ± 0.013 vs 0.053 ± 0.013%∙h, respectively; t-test P = 0.90), or between CORN + MILK vs MILK (0.052 ± 0.024 vs 0.053 ± 0.013%∙h, respectively; t-test P = 0.92). Ingestion of 30 g corn protein, 30 g milk protein, or a blend of 15 g corn plus 15 g milk protein robustly increases muscle protein synthesis rates in young males. The muscle protein synthetic response to the ingestion of 30 g corn-derived protein does not differ from the ingestion of an equivalent amount of milk protein in healthy, young males. Clinical Trial Registry number. NTR6548 (registration date: 27-06-2017) https://www.trialregister.nl/ .},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid38411283b,

title = {Daily blood flow restriction does not preserve muscle mass and strength during 2 weeks of bed rest},

author = {Cas J Fuchs and Wesley J H Hermans and Jean Nyakayiru and Michelle E G Weijzen and Joey S J Smeets and Thorben Aussieker and Joan M Senden and Will K H W Wodzig and Tim Snijders and Lex B Verdijk and Luc J C van Loon},

doi = {10.1113/JP286065},

issn = {1469-7793},

year  = {2024},

date = {2024-02-01},

journal = {J Physiol},

abstract = {We measured the impact of blood flow restriction on muscle protein synthesis rates, muscle mass and strength during 2 weeks of strict bed rest. Twelve healthy, male adults (age: 24 ± 3 years, body mass index: 23.7 ± 3.1 kg/m ) were subjected to 14 days of strict bed rest with unilateral blood flow restriction performed three times daily in three 5 min cycles (200 mmHg). Participants consumed deuterium oxide and we collected blood and saliva samples throughout 2 weeks of bed rest. Before and immediately after bed rest, lean body mass (dual-energy X-ray absorptiometry scan) and thigh muscle volume (magnetic resonance imaging scan) were assessed in both the blood flow restricted (BFR) and control (CON) leg. Muscle biopsies were collected and unilateral muscle strength (one-repetition maximum; 1RM) was assessed for both legs before and after the bed rest period. Bed rest resulted in 1.8 ± 1.0 kg lean body mass loss (P < 0.001). Thigh muscle volume declined from 7.1 ± 1.1 to 6.7 ± 1.0 L in CON and from 7.0 ± 1.1 to 6.7 ± 1.0 L in BFR (P < 0.001), with no differences between treatments (P = 0.497). In addition, 1RM leg extension strength decreased from 60.2 ± 10.6 to 54.8 ± 10.9 kg in CON and from 59.2 ± 12.1 to 52.9 ± 12.0 kg in BFR (P = 0.014), with no differences between treatments (P = 0.594). Muscle protein synthesis rates during bed rest did not differ between the BFR and CON leg (1.11 ± 0.12 vs. 1.08 ± 0.13%/day, respectively; P = 0.302). Two weeks of bed rest substantially reduces skeletal muscle mass and strength. Blood flow restriction during bed rest does not modulate daily muscle protein synthesis rates and does not preserve muscle mass or strength. KEY POINTS: Bed rest, often necessary for recovery from illness or injury, leads to the loss of muscle mass and strength. It has been postulated that blood flow restriction may attenuate the loss of muscle mass and strength during bed rest. We investigated the effect of blood flow restriction on muscle protein synthesis rates, muscle mass and strength during 2 weeks of strict bed rest. Blood flow restriction applied during bed rest does not modulate daily muscle protein synthesis rates and does not preserve muscle mass or strength. Blood flow restriction is not effective in preventing muscle atrophy during a prolonged period of bed rest.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{71b5ec917551427091853b0db550b317,

title = {Benefits of resistance training are not preserved after cessation of supervised training in prostate cancer patients on androgen deprivation therapy},

author = {Lisanne H. P. Houben and Maarten Overkamp and Joan M. G. Senden and Joep G. H. Roermund and Peter Vries and Kevin Laet and Saskia Meer and Luc J. C. Loon and Milou Beelen and Sandra Beijer},

doi = {10.1002/ejsc.12050},

issn = {1746-1391},

year  = {2024},

date = {2024-01-01},

urldate = {2024-01-01},

journal = {European Journal of Sport Science},

volume = {24},

number = {1},

pages = {116–126},

publisher = {Routledge/Taylor & Francis Group},

abstract = {Resistance exercise training is effective to counteract the adverse effects of androgen deprivation therapy (ADT) on body composition, muscle mass and leg strength in prostate cancer patients (PCa). However, it is unknown whether these effects can be autonomously maintained after cessation of the supervised program. Sixty-eight PCa patients on ADT were included. The exercise intervention group (EX, n = 37) performed 20 weeks of supervised resistance exercise training. Thereafter, patients were advised to autonomously continue exercise training. The control group (CON, n = 31) only received usual care. Outcome measures were compared between baseline and after 1 year. Changes during the intervention (baseline vs. 20 weeks) and follow-up period (20 weeks vs. 1 year) were descriptively explored. In EX, 83% reported to have continued exercise training themselves. After 1 year, fat mass gains were attenuated in EX compared to CON (1.2 +/- 2.6 and 2.8 +/- 1.9 kg, respectively; time x treatment effect p = 0.032). The fat percentage increased, and lean mass and quadriceps muscle cross-sectional area decreased over time, with no differences between groups (overall 1.6 +/- 2.1%, -0.7 +/- 2.3 kg and -2.2 +/- 2.9 cm(2), respectively; time effects, all p < 0.05). For muscle strength, an increase of similar to 5% in EX was observed, significantly different from the similar to 10% decrease in CON (p < 0.001). Subsequent analyses showed that the initial exercise training-obtained gains in lean mass, muscle mass and strength in EX compared to CON, declined during the follow-up period. In conclusion, PCa patients on ADT are not capable to autonomously maintain the exercise-obtained gains of a 20-week supervised training program over a subsequent 1-year period},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid37875254b,

title = {Muscle Mass and Strength Gains Following Resistance Exercise Training in Older Adults 65-75 Years and Older Adults Above 85 Years},

author = {Gabriel Nasri Marzuca-Nassr and Andrea Alegría-Molina and Yuri SanMartín-Calísto and Macarena Artigas-Arias and Nolberto Huard and Jorge Sapunar and Luis A Salazar and Lex B Verdijk and Luc J C van Loon},

doi = {10.1123/ijsnem.2023-0087},

issn = {1543-2742},

year  = {2024},

date = {2024-01-01},

journal = {Int J Sport Nutr Exerc Metab},

volume = {34},

number = {1},

pages = {11--19},

abstract = {Resistance exercise training (RET) can be applied effectively to increase muscle mass and function in older adults (65-75 years). However, it has been speculated that older adults above 85 years are less responsive to the benefits of RET. This study compares the impact of RET on muscle mass and function in healthy older adults 65-75 years versus older adults above 85 years. We subjected 17 healthy older adults 65-75 years (OLDER 65-75, n = 13/4 [female/male]; 68 ± 2 years; 26.9 ± 2.3 kg/m2) and 12 healthy older adults above 85 years (OLDER 85+, n = 7/5 [female/male]; 87 ± 3 years; 26.0 ± 3.6 kg/m2) to 12 weeks of whole-body RET (three times per week). Prior to, and after 6 and 12 weeks of training, quadriceps and lumbar spine vertebra 3 muscle cross-sectional area (computed tomography scan), whole-body lean mass (dual-energy X-ray absorptiometry scan), strength (one-repetition maximum test), and physical performance (timed up and go and short physical performance battery) were assessed. Twelve weeks of RET resulted in a 10% ± 4% and 11% ± 5% increase in quadriceps cross-sectional area (from 46.5 ± 10.7 to 51.1 ± 12.1 cm2, and from 38.9 ± 6.1 to 43.1 ± 8.0 cm2, respectively; p < .001; η2 = .67); a 2% ± 3% and 2% ± 3% increase in whole-body lean mass (p = .001; η2 = .22); and a 38% ± 20% and 46% ± 14% increase in one-repetition maximum leg extension strength (p < .001; η2 = .77) in the OLDER 65-75 and OLDER 85+ groups, respectively. No differences in the responses to RET were observed between groups (Time × Group, all p > .60; all η2 ≤ .012). Physical performance on the short physical performance battery and timed up and go improved (both p < .01; η2 ≥ .22), with no differences between groups (Time × Group, p > .015; η2 ≤ .07). Prolonged RET increases muscle mass, strength, and physical performance in the aging population, with no differences between 65-75 years and 85+ years older adults.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid37883634b,

title = {Jumping Exercise Combined With Collagen Supplementation Preserves Bone Mineral Density in Elite Cyclists},

author = {Luuk Hilkens and Nick van Schijndel and Vera C R Weijer and Lieselot Decroix and Judith Bons and Luc J C van Loon and Jan-Willem van Dijk},

doi = {10.1123/ijsnem.2023-0080},

issn = {1543-2742},

year  = {2024},

date = {2024-01-01},

journal = {Int J Sport Nutr Exerc Metab},

volume = {34},

number = {1},

pages = {38--47},

abstract = {This study assessed the effect of combined jump training and collagen supplementation on bone mineral density (BMD) in elite road-race cyclists. In this open-label, randomized study with two parallel groups, 36 young (21 ± 3 years) male (n = 8) and female (n = 28) elite road-race cyclists were allocated to either an intervention (INT: n = 18) or a no-treatment control (CON: n = 18) group. The 18-week intervention period, conducted during the off-season, comprised five 5-min bouts of jumping exercise per week, with each bout preceded by the ingestion of 15 g hydrolyzed collagen. Before and after the intervention, BMD of various skeletal sites and trabecular bone score of the lumbar spine were assessed by dual-energy X-ray absorptiometry, along with serum bone turnover markers procollagen Type I N propeptide and carboxy-terminal cross-linking telopeptide of Type I collagen. BMD of the femoral neck decreased in CON (from 0.789 ± 0.104 to 0.774 ± 0.095 g/cm2), while being preserved in INT (from 0.803 ± 0.058 to 0.809 ± 0.066 g/cm2; Time × Treatment, p < .01). No differences between treatments were observed for changes in BMD at the total hip, lumbar spine, and whole body (Time × Treatment, p > .05 for all). Trabecular bone score increased from 1.38 ± 0.08 to 1.40 ± 0.09 in CON and from 1.46 ± 0.08 to 1.47 ± 0.08 in INT, respectively (time effect: p < .01), with no differences between treatments (Time × Treatment: p = .33). Serum procollagen Type I N propeptide concentrations decreased to a similar extent in CON (83.6 ± 24.8 to 71.4 ± 23.1 ng/ml) and INT (82.8 ± 30.7 to 66.3 ± 30.6; time effect, p < .001; Time × Treatment, p = .22). Serum carboxy-terminal cross-linking telopeptide of Type I collagen concentrations did not change over time, with no differences between treatments (time effect, p = .08; Time × Treatment, p = .58). In conclusion, frequent short bouts of jumping exercise combined with collagen supplementation beneficially affects femoral neck BMD in elite road-race cyclists.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid38109855b,

title = {Type II Muscle Fiber Capillarization Is an Important Determinant of Post-Exercise Microvascular Perfusion in Older Adults},

author = {Milan W Betz and Floris K Hendriks and Alfons J H M Houben and Mathias D G van den Eynde and Lex B Verdijk and Luc J C van Loon and Tim Snijders},

doi = {10.1159/000535831},

issn = {1423-0003},

year  = {2024},

date = {2024-01-01},

journal = {Gerontology},

volume = {70},

number = {3},

pages = {290--301},

abstract = {INTRODUCTION: Microvascular perfusion is essential for post-exercise skeletal muscle recovery to ensure adequate delivery of nutrients and growth factors. This study assessed the relationship between various indices of muscle fiber capillarization and microvascular perfusion assessed by contrast-enhanced ultrasound (CEUS) at rest and during recovery from a bout of resistance exercise in older adults.nnMETHODS: Sixteen older adults (72 ± 6 y, 5/11 male/female) participated in an experimental test day during which a muscle biopsy was collected from the vastus lateralis and microvascular perfusion was determined by CEUS at rest and at 10 and 40 min following a bout of resistance exercise. Immunohistochemistry was performed on muscle tissue samples to determine various indices of both mixed and fiber-type-specific muscle fiber capillarization.nnRESULTS: Microvascular blood volume at t = 10 min was higher compared with rest and t = 40 min (27.2 ± 4.7 vs. 3.9 ± 4.0 and 7.0 ± 4.9 AU, respectively, both p < 0.001). Microvascular blood volume at t = 40 min was higher compared with rest (p < 0.001). No associations were observed between different indices of mixed muscle fiber capillarization and microvascular blood volume at rest and following exercise. A moderate (r = 0.59, p < 0.05) and strong (r = 0.81, p < 0.001) correlation was observed between type II muscle fiber capillary-to-fiber ratio and the microvascular blood volume increase from rest to t = 10 and t = 40 min, respectively. In addition, type II muscle fiber capillary contacts and capillary-to-fiber perimeter exchange index were strongly correlated with the microvascular blood volume increase from rest to t = 40 min (r = 0.66, p < 0.01 and r = 0.64, p < 0.01, respectively).nnCONCLUSION: Resistance exercise strongly increases microvascular blood volume for at least 40 min after exercise cessation in older adults. This resistance exercise-induced increase in microvascular blood volume is strongly associated with type II muscle fiber capillarization in older adults.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid38194704b,

title = {Energy Requirements of Paralympic Athletes: Insights from the Doubly Labeled Water Approach},

author = {Vera C R Weijer and Kristin L Jonvik and Lotte van Dam and Linn Risvang and Guy Plasqui and Øyvind Sandbakk and Truis Raastad and Luc J C van Loon and Jan-Willem van Dijk},

doi = {10.1249/MSS.0000000000003379},

issn = {1530-0315},

year  = {2024},

date = {2024-01-01},

journal = {Med Sci Sports Exerc},

abstract = {PURPOSE: Advanced insight in energy requirements of Paralympic athletes is imperative for optimizing their nutritional counseling. Given the lack of accurate data on total daily energy expenditure (TDEE) of Paralympic athletes, this study aimed to assess energy expenditure and nutritional intake of a large cohort of Paralympic athletes, across different sports and disabilities.nnMETHODS: In this cross-sectional study, 48 Dutch and Norwegian Paralympic athletes (19 male/29 female) with various disabilities, competing in Para cycling, wheelchair tennis, wheelchair basketball, Para Nordic skiing and alpine skiing participated. TDEE was assessed by the gold standard doubly labeled water method over a 14-day period, resting metabolic rate (RMR) by ventilated hood indirect calorimetry, energy intake (EI) by three unannounced 24 h-dietary recalls, body composition by dual energy x-ray absorptiometry and exercise training duration by a training log.nnRESULTS: Mean TDEE was 2908 ± 797 kcal/day, ranging from 2322 ± 340 kcal/day for wheelchair basketball players to 3607 ± 1001 kcal/day for Para cyclists. Regression analysis identified fat-free mass, exercise duration, and the presence of a spinal cord disorder as the primary predictors of TDEE, explaining up to 73% of the variance in TDEE. Athletes' EI (2363 ± 905 kcal/day) was below their TDEE, while their body mass remained constant, indicating underreporting. Carbohydrate intake (4.1 ± 1.9 g/kg body mass) was low, even when considering underreporting, while protein intake (1.8 ± 0.6 g/kg body mass) was relatively high.nnCONCLUSIONS: Paralympic athletes display moderate to high energy expenditure, varying across sports and individuals. Much of the variation in TDEE can be attributed to individual differences in fat free mass and exercise duration. This study establishes the benchmarks for energy requirements of Paralympic athletes, serving as the foundation for future dietary guidelines within this population.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid37769955,

title = {Trabecular, but not cortical, bone tissue protein synthesis rates are lower in the femoral head when compared to the proximal femur following an intracapsular hip fracture},

author = {Floris K Hendriks and Michelle E G Weijzen and Joy P B Goessens and Antoine H G Zorenc and Annemie P Gijsen and Irene Fleur Kramer and Joop P W van den Bergh and Martijn Poeze and Taco J Blokhuis and Luc J C van Loon},

doi = {10.1016/j.bone.2023.116921},

issn = {1873-2763},

year  = {2023},

date = {2023-12-01},

journal = {Bone},

volume = {177},

pages = {116921},

abstract = {BACKGROUND: All musculoskeletal tissues are in a constant state of turnover, with a dynamic equilibrium between tissue protein synthesis and breakdown rates. The synthesis of protein allows musculoskeletal tissues to heal following injury. Yet, impaired tissue healing is observed following certain injuries, such as geriatric hip fractures. It is assumed that the regenerative properties of femoral head bone tissue are compromised following an intracapsular hip fracture and therefore hip replacement surgery is normally performed. However, the actual impact on in vivo bone protein synthesis rates has never been determined.nnDESIGN: In the present study, 10 patients (age: 79 ± 10 y, BMI: 24 ± 4 kg/m) with an acute (<24 h) intracapsular hip fracture received a primed continuous intravenous infusion of L-[ring-C]-phenylalanine before and throughout their hip replacement surgery. Trabecular and cortical bone tissue from both the femoral head and proximal femur were sampled during surgery to assess protein synthesis rates of affected (femoral head) and unaffected (proximal femur) bone tissue, respectively. In addition, tissue samples of gluteus maximus muscle, synovium, ligamentum teres, and femoral head cartilage were collected. Tissue-specific protein synthesis rates were assessed by measuring L-[ring-C]-phenylalanine incorporation in tissue protein.nnRESULTS: Femoral head trabecular bone protein synthesis rates (0.056 [0.024-0.086] %/h) were lower when compared to proximal femur trabecular bone protein synthesis rates (0.081 [0.056-0.118] %/h; P = 0.043). Cortical bone protein synthesis rates did not differ between the femoral head and proximal femur (0.041 [0.021-0.078] and 0.045 [0.028-0.073] %/h, respectively; P > 0.05). Skeletal muscle, synovium, ligamentum teres, and femoral head cartilage protein synthesis rates averaged 0.080 [0.048-0.089], 0.093 [0.051-0.130], 0.121 [0.110-0.167], and 0.023 [0.015-0.039] %/h, respectively.nnCONCLUSION: In contrast to the general assumption that the femoral head is avital after an intracapsular displaced hip fracture in the elderly, our data show that bone protein synthesis is still ongoing in femoral head bone tissue during the early stages following an intracapsular hip fracture in older patients. Nonetheless, trabecular bone protein synthesis rates are lower in the femoral head when compared to the proximal femur in older patients following an acute intracapsular hip fracture. Trial register no: NL9036.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid38118410,

title = {The anabolic response to protein ingestion during recovery from exercise has no upper limit in magnitude and duration in vivo in humans},

author = {Jorn Trommelen and Glenn A A van Lieshout and Jean Nyakayiru and Andrew M Holwerda and Joey S J Smeets and Floris K Hendriks and Janneau M X van Kranenburg and Antoine H Zorenc and Joan M Senden and Joy P B Goessens and Annemie P Gijsen and Luc J C van Loon},

doi = {10.1016/j.xcrm.2023.101324},

issn = {2666-3791},

year  = {2023},

date = {2023-12-01},

journal = {Cell Rep Med},

volume = {4},

number = {12},

pages = {101324},

abstract = {The belief that the anabolic response to feeding during postexercise recovery is transient and has an upper limit and that excess amino acids are being oxidized lacks scientific proof. Using a comprehensive quadruple isotope tracer feeding-infusion approach, we show that the ingestion of 100 g protein results in a greater and more prolonged (>12 h) anabolic response when compared to the ingestion of 25 g protein. We demonstrate a dose-response increase in dietary-protein-derived plasma amino acid availability and subsequent incorporation into muscle protein. Ingestion of a large bolus of protein further increases whole-body protein net balance, mixed-muscle, myofibrillar, muscle connective, and plasma protein synthesis rates. Protein ingestion has a negligible impact on whole-body protein breakdown rates or amino acid oxidation rates. These findings demonstrate that the magnitude and duration of the anabolic response to protein ingestion is not restricted and has previously been underestimated in vivo in humans.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid37202878,

title = {Collagen Protein Ingestion during Recovery from Exercise Does Not Increase Muscle Connective Protein Synthesis Rates},

author = {Thorben Aussieker and Luuk Hilkens and Andrew M Holwerda and Cas J Fuchs and Lisanne H P Houben and Joan M Senden and Jan-Willem VAN Dijk and Tim Snijders and Luc J C VAN Loon},

doi = {10.1249/MSS.0000000000003214},

issn = {1530-0315},

year  = {2023},

date = {2023-10-01},

journal = {Med Sci Sports Exerc},

volume = {55},

number = {10},

pages = {1792--1802},

abstract = {INTRODUCTION: Protein ingestion during recovery from exercise has been reported to augment myofibrillar protein synthesis rates, without increasing muscle connective protein synthesis rates. It has been suggested that collagen protein may be effective in stimulating muscle connective protein synthesis. The present study assessed the capacity of both whey and collagen protein ingestion to stimulate postexercise myofibrillar and muscle connective protein synthesis rates.nnMETHODS: In a randomized, double-blind, parallel design, 45 young male ( n = 30) and female ( n = 15) recreational athletes (age, 25 ± 4 yr; body mass index, 24.1 ± 2.0 kg·m -2 ) were selected to receive primed continuous intravenous infusions with l -[ring- 13 C 6 ]-phenylalanine and l -[3,5- 2 H 2 ]-tyrosine. After a single session of resistance type exercise, subjects were randomly allocated to one of three groups ingesting either 30 g whey protein (WHEY, n = 15), 30 g collagen protein (COLL, n = 15) or a noncaloric placebo (PLA, n = 15). Blood and muscle biopsy samples were collected over a subsequent 5-h recovery period to assess both myofibrillar and muscle connective protein synthesis rates.nnRESULTS: Protein ingestion increased circulating plasma amino acid concentrations ( P < 0.05). The postprandial rise in plasma leucine and essential amino acid concentrations was greater in WHEY compared with COLL, whereas plasma glycine and proline concentrations increased more in COLL compared with WHEY ( P < 0.05). Myofibrillar protein synthesis rates averaged 0.041 ± 0.010, 0.036 ± 0.010, and 0.032 ± 0.007%·h -1 in WHEY, COLL and PLA, respectively, with only WHEY resulting in higher rates when compared with PLA ( P < 0.05). Muscle connective protein synthesis rates averaged 0.072 ± 0.019, 0.068 ± 0.017, and 0.058 ± 0.018%·h -1 in WHEY, COLL, and PLA, respectively, with no significant differences between groups ( P = 0.09).nnCONCLUSIONS: Ingestion of whey protein during recovery from exercise increases myofibrillar protein synthesis rates. Neither collagen nor whey protein ingestion further increased muscle connective protein synthesis rates during the early stages of postexercise recovery in both male and female recreational athletes.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid36574223,

title = {Observations of nemaline bodies in muscle biopsies of critically ill patients infected with SARS-CoV-2},

author = {Frank Vandenabeele and Sjoerd Stevens and Tim Snijders and Björn Stessel and Jasperina Dubois and Luc J C van Loon and Ivo Lambrichts and Anouk Agten},

doi = {10.1093/jmicro/dfac072},

issn = {2050-5701},

year  = {2023},

date = {2023-10-01},

journal = {Microscopy (Oxf)},

volume = {72},

number = {5},

pages = {388--394},

abstract = {Patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) who have been admitted to the intensive care unit (ICU) often face months of physical disability after discharge. To optimize recovery, it is important to understand the role of musculoskeletal alterations in critically ill patients infected with SARS-CoV-2. The main aim of the present study was to describe the presence and morphology of nemaline bodies found in the skeletal muscle tissue from critically ill patients infected with SARS-CoV-2. In n = 7 patients infected with SARS-CoV-2, ultrastructural characteristics of vastus lateralis muscle obtained on days 1-3 and days 5-8 following ICU admission were investigated in more detail with electron microscopy. Those muscle biopsies consistently showed variable degrees of myofiber necrosis and myofibrillar disorganization. In 4/7 (57%) patients on days 5-8, the Z-line material accumulated into nemaline bodies with a typical lattice-like appearance at higher magnification, similar to that found in nemaline myopathy. This study is the first to describe the disintegration of myofibrils and the accumulation of Z-line material into nemaline bodies in the skeletal muscle tissue obtained from critically ill coronavirus disease-19 patients following ICU admission, which should be interpreted primarily as a non-specific pathological response of extreme myofibrillar disintegration associated with myofiber necrosis.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid37348850,

title = {The Postprandial Plasma Amino Acid Response Does Not Differ Following the Ingestion of a Solid Versus a Liquid Milk Protein Product in Healthy Adult Females},

author = {Glenn A A van Lieshout and Jorn Trommelen and Jean Nyakayiru and Janneau van Kranenburg and Joan M Senden and Lex B Verdijk and Luc J C van Loon},

doi = {10.1123/ijsnem.2023-0038},

issn = {1543-2742},

year  = {2023},

date = {2023-09-01},

journal = {Int J Sport Nutr Exerc Metab},

volume = {33},

number = {5},

pages = {247--254},

abstract = {Dietary protein digestion and amino acid absorption rates are modulated by numerous factors such as the food matrix. It has been speculated that protein ingested in liquid form is more rapidly digested and absorbed when compared with ingestion in solid form. Here, we assessed the postprandial plasma amino acid availability following ingestion of a single bolus of protein provided in either liquid or solid form. Twelve healthy, young females were included in this randomized cross-over study. On two separate test days, participants ingested 20-g milk protein concentrate in solid form (protein bar) or in liquid form (protein drink). Products were composed of matched ingredients and, thereby, had the same macro- and micronutrient composition. On both test days, arterialized blood samples were collected at regular time intervals for up to 4 hr following protein ingestion to assess the postprandial rise in plasma amino acid concentrations. Protein ingestion robustly elevated circulating plasma amino acid concentrations (p < .001), with no significant differences between treatments (p = .088). The incremental area under the curve of the postprandial rise in total plasma amino acid concentrations did not differ following bar versus drink consumption (160 ± 73 vs. 160 ± 71 mmol·L-1·240 min-1, respectively; 95% confidence interval [-37, 37]; Cohen's dz = 0.003; p = .992). Ingestion of protein in liquid or solid form does not modulate postprandial amino acid availability in healthy, female adults. Any differences in protein digestion and amino acid absorption due to differences in food matrix are not attributed to the protein being consumed as a bar or as a drink.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid37161470,

title = {Resistance Exercise Counteracts the Impact of Androgen Deprivation Therapy on Muscle Characteristics in Cancer Patients},

author = {Maarten Overkamp and Lisanne H P Houben and Thorben Aussieker and Janneau M X van Kranenburg and Philippe J M Pinckaers and Ulla R Mikkelsen and Milou Beelen and Sandra Beijer and Luc J C van Loon and Tim Snijders},

doi = {10.1210/clinem/dgad245},

issn = {1945-7197},

year  = {2023},

date = {2023-09-01},

journal = {J Clin Endocrinol Metab},

volume = {108},

number = {10},

pages = {e907--e915},

abstract = {CONTEXT: Androgen deprivation therapy (ADT) forms the cornerstone in prostate cancer (PCa) treatment. However, ADT also lowers skeletal muscle mass.nnOBJECTIVE: To identify the impact of ADT with and without resistance exercise training on muscle fiber characteristics in PCa patients.nnMETHODS: Twenty-one PCa patients (72 ± 6 years) starting ADT were included. Tissue samples from the vastus lateralis muscle were assessed at baseline and after 20 weeks of usual care (n = 11) or resistance exercise training (n = 10). Type I and II muscle fiber distribution, fiber size, and myonuclear and capillary contents were determined by immunohistochemistry.nnRESULTS: Significant decreases in type I (from 7401 ± 1183 to 6489 ± 1293 μm2, P < .05) and type II (from 6225 ± 1503 to 5014 ± 714 μm2, P < .05) muscle fiber size were observed in the usual care group. In addition, type I and type II individual capillary-to-fiber ratio (C/Fi) declined (-12% ± 12% and -20% ± 21%, respectively, P < .05). In contrast, significant increases in type I (from 6700 ± 1464 to 7772 ± 1319 μm2, P < .05) and type II (from 5248 ± 892 to 6302 ± 1385 μm2, P < .05) muscle fiber size were observed in the training group, accompanied by an increase in type I and type II muscle fiber myonuclear contents (+24% ± 33% and +21% ± 23%, respectively, P < .05) and type I C/Fi (+18% ± 14%, P < .05).nnCONCLUSION: The onset of ADT is followed by a decline in both type I and type II muscle fiber size and capillarization in PCa patients. Resistance exercise training offsets the negative impact of ADT and increases type I and II muscle fiber size and type I muscle fiber capillarization in these patients.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid37441814,

title = {Branched-chain ketoacid co-ingestion with protein lowers amino acid oxidation during hemodialysis: A randomized controlled cross-over trial},

author = {Floris K Hendriks and Jorn Trommelen and Frank M van der Sande and Janneau M X van Kranenburg and Jeffrey H W Kuijpers and Dion C J Houtvast and Guus H J Jetten and Joy P B Goessens and Steven J R Meex and Jeroen P Kooman and Luc J C van Loon},

doi = {10.1016/j.clnu.2023.06.034},

issn = {1532-1983},

year  = {2023},

date = {2023-08-01},

journal = {Clin Nutr},

volume = {42},

number = {8},

pages = {1436--1444},

abstract = {BACKGROUND & AIMS: Hemodialysis removes amino acids from the circulation, thereby stimulating muscle proteolysis. Protein ingestion during hemodialysis can compensate for amino acid removal but may also increase uremic toxin production. Branched-chain ketoacid (BCKA) co-ingestion may provide an additional anabolic stimulus without adding to uremic toxin accumulation. In the present study we assessed the impact of BCKA co-ingestion with protein on forearm amino acid balance and amino acid oxidation during hemodialysis.nnMETHODS: Nine patients (age: 73 ± 10 y) on chronic hemodialysis participated in this crossover trial. During two 4-h hemodialysis sessions, patients ingested 18 g protein with (PRO + BCKA) or without (PRO) 9 g BCKAs in a randomized order. Test beverages were labeled with L-[ring-C]-phenylalanine and provided throughout the last 3 h of hemodialysis as 18 equal sips consumed with 10-min intervals. Arterial and venous plasma as well as breath samples were collected frequently throughout hemodialysis.nnRESULTS: Arterial plasma total amino acid (TAA) concentrations during PRO and PRO + BCKA treatments were significantly lower after 1 h of hemodialysis (2.6 ± 0.3 and 2.6 ± 0.3 mmol/L, respectively) when compared to pre-hemodialysis concentrations (4.2 ± 1.0 and 4.0 ± 0.5 mmol/L, respectively; time effect: P < 0.001). Arterial plasma TAA concentrations increased throughout test beverage ingestion (time effect: P = 0.027) without differences between treatments (time∗treatment: P = 0.62). Forearm arteriovenous TAA balance during test beverage ingestion did not differ between timepoints (time effect: P = 0.31) or treatments (time∗treatment: P = 0.34). Whole-body phenylalanine oxidation was 33 ± 16% lower during PRO + BCKA when compared to PRO treatments (P < 0.001).nnCONCLUSIONS: BCKA co-ingestion with protein during hemodialysis does not improve forearm net protein balance but lowers amino acid oxidation.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}