Protein Ingestion to Stimulate Myofibrillar Protein Synthesis Requires Greater Relative Protein Intakes in Healthy Older Versus Younger Men

The purpose of this study was to determine the impact of ingesting 30 g casein protein with and without 2 g free leucine before sleep on myofibrillar protein synthesis rates during postexercise overnight recovery. Thirty-six healthy young men performed a single bout of resistance-type exercise in the evening (1945) after a full day of dietary standardization. Thirty minutes before sleep (2330), subjects ingested 30 g intrinsically l-[1-13C]phenylalanine-labeled protein with (PRO+leu, n = 12) or without (PRO, n = 12) 2 g free leucine, or a noncaloric placebo (PLA, n = 12). Continuous intravenous l-[ ring-2H5]phenylalanine, l-[1-13C]leucine, and l-[ ring-2H2]tyrosine infusions were applied. Blood and muscle tissue samples were collected to assess whole body protein net balance, myofibrillar protein synthesis rates, and overnight incorporation of dietary protein-derived amino acids into myofibrillar protein. Protein ingestion before sleep improved overnight whole body protein net balance ( P < 0.001). Myofibrillar protein synthesis rates did not differ significantly between treatments as assessed by l-[ ring-2H5]phenylalanine (0.057 ± 0.002, 0.055 ± 0.002, and 0.055 ± 0.004%/h for PLA, PRO, and PRO+leu, respectively; means ± SE; P = 0.850) or l-[1-13C]leucine (0.080 ± 0.004, 0.073 ± 0.004, and 0.083 ± 0.006%/h, respectively; P = 0.328). Myofibrillar l-[1-13C]phenylalanine enrichments increased following protein ingestion but did not differ between the PRO and PRO+leu treatments. In conclusion, protein ingestion before sleep improves whole body protein net balance and provides amino acids that are incorporated into myofibrillar protein during sleep. However, the ingestion of 30 g casein protein with or without additional free leucine before sleep does not increase muscle protein synthesis rates during postexercise overnight recovery.

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Basal and Postprandial Myofibrillar Protein Synthesis Rates Do Not Differ between Lean and Obese Middle-Aged Men

Journal of Nutrition ◽

10.1093/jn/nxz104 ◽

2019 ◽

Vol 149 (9) ◽

pp. 1533-1542 ◽

Cited By ~ 5

Author(s):

Imre W K Kouw ◽

Jan Willem van Dijk ◽

Astrid M H Horstman ◽

Irene Fleur Kramer ◽

Joy P B Goessens ◽

...

Keyword(s):

Protein Synthesis ◽

Amino Acid ◽

Muscle Protein ◽

Myofibrillar Protein ◽

Whole Body ◽

Protein Digestion ◽

Body Protein ◽

Postprandial Period ◽

Protein Ingestion ◽

Myofibrillar Protein Synthesis

ABSTRACT Background Excess lipid availability has been associated with the development of anabolic resistance. As such, obesity may be accompanied by impairments in muscle protein metabolism. Objective We hypothesized that basal and postprandial muscle protein synthesis rates are lower in obese than in lean men. Methods Twelve obese men [mean ± SEM age: 48 ± 2 y; BMI (in kg/m2): 37.0 ± 1.5; body fat: 32 ± 2%] and 12 age-matched lean controls (age: 43 ± 3 y; BMI: 23.4 ± 0.4; body fat: 21 ± 1%) received primed continuous L-[ring-2H5]-phenylalanine and L-[ring-3,5-2H2]-tyrosine infusions and ingested 25 g intrinsically L-[1-13C]-phenylalanine labeled whey protein. Repeated blood and muscle samples were obtained to assess protein digestion and amino acid absorption kinetics, and basal and postprandial myofibrillar protein synthesis rates. Results Exogenous phenylalanine appearance rates increased after protein ingestion in both groups (P < 0.001), with a total of 53 ± 1% and 53 ± 2% of dietary protein–derived phenylalanine appearing in the circulation over the 5-h postprandial period in lean and obese men, respectively (P = 0.82). After protein ingestion, whole-body protein synthesis and oxidation rates increased to a greater extent in lean men than in the obese (P-interaction < 0.05), resulting in a higher whole-body protein net balance in the lean than in the obese (7.1 ± 0.2 and 4.6 ± 0.4 µmol phenylalanine · h−1 · kg−1, respectively; P-interaction < 0.001). Myofibrillar protein synthesis rates increased from 0.030 ± 0.002 and 0.028 ± 0.003%/h in the postabsorptive period to 0.034 ± 0.002 and 0.035 ± 0.003%.h−1 in the 5-h postprandial period (P = 0.03) in lean and obese men, respectively, with no differences between groups (P-interaction = 0.58). Conclusions Basal, postabsorptive myofibrillar protein synthesis rates do not differ between lean and obese middle-aged men. Postprandial protein handling, including protein digestion and amino acid absorption, and the postprandial muscle protein synthetic response after the ingestion of 25 g whey protein are not impaired in obese men. This trial was registered at www.trialregister.nl as NTR4060.

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Protein Ingestion Increases Myofibrillar Protein Synthesis after Concurrent Exercise

Medicine & Science in Sports & Exercise ◽

10.1249/mss.0000000000000390 ◽

2015 ◽

Vol 47 (1) ◽

pp. 82-91 ◽

Cited By ~ 29

Author(s):

DONNY M. CAMERA ◽

DANIEL W. D. WEST ◽

STUART M. PHILLIPS ◽

TRACY RERECICH ◽

TRENT STELLINGWERFF ◽

...

Keyword(s):

Protein Synthesis ◽

Myofibrillar Protein ◽

Protein Ingestion ◽

Concurrent Exercise ◽

Myofibrillar Protein Synthesis

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Sex-based comparisons of myofibrillar protein synthesis after resistance exercise in the fed state

Journal of Applied Physiology ◽

10.1152/japplphysiol.00170.2012 ◽

2012 ◽

Vol 112 (11) ◽

pp. 1805-1813 ◽

Cited By ~ 55

Author(s):

Daniel W. D. West ◽

Nicholas A. Burd ◽

Tyler A. Churchward-Venne ◽

Donny M. Camera ◽

Cameron J. Mitchell ◽

...

Keyword(s):

Protein Synthesis ◽

Resistance Exercise ◽

Vastus Lateralis ◽

Recovery Period ◽

Myofibrillar Protein ◽

Men And Women ◽

Fed State ◽

Protein Ingestion ◽

Exercise Induced ◽

Myofibrillar Protein Synthesis

We made sex-based comparisons of rates of myofibrillar protein synthesis (MPS) and anabolic signaling after a single bout of high-intensity resistance exercise. Eight men (20 ± 10 yr, BMI = 24.3 ± 2.4) and eight women (22 ± 1.8 yr, BMI = 23.0 ± 1.9) underwent primed constant infusions of l-[ ring-13C6]phenylalanine on consecutive days with serial muscle biopsies. Biopsies were taken from the vastus lateralis at rest and 1, 3, 5, 24, 26, and 28 h after exercise. Twenty-five grams of whey protein was ingested immediately and 26 h after exercise. We also measured exercise-induced serum testosterone because it is purported to contribute to increases in myofibrillar protein synthesis (MPS) postexercise and its absence has been hypothesized to attenuate adaptative responses to resistance exercise in women. The exercise-induced area under the testosterone curve was 45-fold greater in men than women in the early (1 h) recovery period following exercise ( P < 0.001). MPS was elevated similarly in men and women (2.3- and 2.7-fold, respectively) 1–5 h postexercise and after protein ingestion following 24 h recovery. Phosphorylation of mTORSer2448 was elevated to a greater extent in men than women acutely after exercise ( P = 0.003), whereas increased phosphorylation of p70S6K1Thr389 was not different between sexes. Androgen receptor content was greater in men (main effect for sex, P = 0.049). Atrogin-1 mRNA abundance was decreased after 5 h recovery in both men and women ( P < 0.001), and MuRF-1 expression was elevated in men after protein ingestion following 24 h recovery ( P = 0.003). These results demonstrate minor sex-based differences in signaling responses and no difference in the MPS response to resistance exercise in the fed state. Interestingly, our data demonstrate that exercise-induced increases in MPS are dissociated from postexercise testosteronemia and that stimulation of MPS occurs effectively with low systemic testosterone concentrations in women.

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The Muscle Protein Synthetic Response Following Ingestion of Corn Protein, Milk Protein and Their Protein Blend in Young Males

Current Developments in Nutrition ◽

10.1093/cdn/nzaa049_044 ◽

2020 ◽

Vol 4 (Supplement_2) ◽

pp. 651-651

Author(s):

Philippe J M Pinckaers ◽

Michelle E G Weijzen ◽

Lisanne H P Houben ◽

Antoine H Zorenc ◽

Imre W K Kouw ◽

...

Keyword(s):

Protein Synthesis ◽

Milk Protein ◽

Muscle Protein ◽

Muscle Protein Synthesis ◽

Myofibrillar Protein ◽

Young Males ◽

Corn Protein ◽

Protein Ingestion ◽

Myofibrillar Protein Synthesis

Abstract Objectives The muscle protein synthetic response to the ingestion of animal based proteins has been reported to be superior to the ingestion of plant based proteins. The lesser anabolic properties of plant based compared with animal based proteins has been attributed to differences in essential amino acid (EAA) contents and amino acid composition. This study compares post-prandial muscle protein synthesis rates following the ingestion of 30 g milk protein with the ingestion of 30 g corn protein or a blend of 30 g corn and milk protein in vivo, in young males. Methods In a randomized, double blind, parallel-group design, 36 healthy young males (26 ± 4 y) received a primed continuous infusion of L-[ring-13C6]-phenylalanine and ingested 30 g milk protein (MILK), 30 g corn protein (CORN), or a blend of 15 g corn protein plus 15 g milk protein (CORN + MILK) (n = 12 per group). 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. Data were analyzed with 2-way repeated measures ANOVA and independent samples t-test. Data are expressed as mean ± SD. Results MILK increased plasma EAA concentrations more when compared to CORN (incremental area under curve (iAUC): 151 ± 31 vs 77 ± 19 mmol/L/300 min, respectively; P < 0.001). Both milk and corn protein ingestion increased myofibrillar protein synthesis rates (P < 0.001), with no differences between MILK and CORN (from 0.014 ± 0.014 to 0.053 ± 0.013 and from 0.017 ± 0.011 to 0.052 ± 0.013%/h, respectively; time*treatment P = 0.661). When MILK was compared to CORN + MILK, the iAUC for plasma EAA concentrations increased more in MILK when compared to CORN + MILK (151 ± 31 vs 126 ± 24 mmol/L/300 min, respectively; P = 0.036). Corn plus milk protein ingestion also increased myofibrillar protein synthesis rates (from 0.015 ± 0.015 to 0.052 ± 0.024%/h; P < 0.001), with no differences between MILK and CORN + MILK (time*treatment P = 0.823). Conclusions Ingestion of 30 g milk protein, 30 g corn protein, or a blend of 15 g corn plus 15 g milk protein increases muscle protein synthesis rates in vivo in young males. Post-prandial muscle protein synthesis rates following the ingestion of 30 g milk protein do not differ from rates observed after ingesting 30 g corn protein or a blend providing 15 g milk plus 15 g corn protein in vivo, in young males. Funding Sources TiFN.

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Presleep protein ingestion does not compromise the muscle protein synthetic response to protein ingested the following morning

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.00325.2016 ◽

2016 ◽

Vol 311 (6) ◽

pp. E964-E973 ◽

Cited By ~ 19

Author(s):

Benjamin T. Wall ◽

Nicholas A. Burd ◽

Rinske Franssen ◽

Stefan H. M. Gorissen ◽

Tim Snijders ◽

...

Keyword(s):

Protein Synthesis ◽

Muscle Protein ◽

Muscle Protein Synthesis ◽

Myofibrillar Protein ◽

Protein Supplementation ◽

Protein Consumption ◽

Nutrient Timing ◽

Protein Ingestion ◽

Postexercise Recovery ◽

Myofibrillar Protein Synthesis

Protein ingestion before sleep augments postexercise muscle protein synthesis during overnight recovery. It is unknown whether postexercise and presleep protein consumption modulates postprandial protein handling and myofibrillar protein synthetic responses the following morning. Sixteen healthy young (24 ± 1 yr) men performed unilateral resistance-type exercise (contralateral leg acting as a resting control) at 2000. Participants ingested 20 g of protein immediately after exercise plus 60 g of protein presleep (PRO group; n = 8) or equivalent boluses of carbohydrate (CON; n = 8). The subsequent morning participants received primed, continuous infusions of l-[ ring-2H5]phenylalanine and l-[1-13C]leucine combined with ingestion of 20 g intrinsically l-[1-13C]phenylalanine- and l-[1-13C]leucine-labeled protein to assess postprandial protein handling and myofibrillar protein synthesis in the rested and exercised leg in CON and PRO. Exercise increased postabsorptive myofibrillar protein synthesis rates the subsequent day ( P < 0.001), with no differences between CON and PRO. Protein ingested in the morning increased myofibrillar protein synthesis in both the exercised and rested leg ( P < 0.01), with no differences between treatments. Myofibrillar protein bound l-[1-13C]phenylalanine enrichments were greater in the exercised (0.016 ± 0.002 and 0.015 ± 0.002 MPE in CON and PRO, respectively) vs. rested (0.010 ± 0.002 and 0.009 ± 0.002 MPE in CON and PRO, respectively) leg ( P < 0.05), with no differences between treatments ( P > 0.05). The additive effects of resistance-type exercise and protein ingestion on myofibrillar protein synthesis persist for more than 12 h after exercise and are not modulated by protein consumption during acute postexercise recovery. This work provides evidence of an extended window of opportunity where presleep protein supplementation can be an effective nutrient timing strategy to optimize skeletal muscle reconditioning.

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Exercise Plus Presleep Protein Ingestion Increases Overnight Muscle Connective Tissue Protein Synthesis Rates in Healthy Older Men

International Journal of Sport Nutrition and Exercise Metabolism ◽

10.1123/ijsnem.2020-0222 ◽

2021 ◽

Vol 31 (3) ◽

pp. 217-226 ◽

Cited By ~ 1

Author(s):

Andrew M. Holwerda ◽

Jorn Trommelen ◽

Imre W.K. Kouw ◽

Joan M. Senden ◽

Joy P.B. Goessens ◽

...

Keyword(s):

Protein Synthesis ◽

Connective Tissue ◽

Dietary Protein ◽

Older Men ◽

Myofibrillar Protein ◽

Tissue Protein ◽

Protein Ingestion ◽

Tissue Protein Synthesis ◽

Casein Protein ◽

Myofibrillar Protein Synthesis

Protein ingestion and exercise stimulate myofibrillar protein synthesis rates. When combined, exercise further increases the postprandial rise in myofibrillar protein synthesis rates. It remains unclear whether protein ingestion with or without exercise also stimulates muscle connective tissue protein synthesis rates. The authors assessed the impact of presleep protein ingestion on overnight muscle connective tissue protein synthesis rates at rest and during recovery from resistance-type exercise in older men. Thirty-six healthy, older men were randomly assigned to ingest 40 g intrinsically L-[1-13C]-phenylalanine and L-[1-13C]-leucine-labeled casein protein (PRO, n = 12) or a nonprotein placebo (PLA, n = 12) before going to sleep. A third group performed a single bout of resistance-type exercise in the evening before ingesting 40 g intrinsically-labeled casein protein prior to sleep (EX+PRO, n = 12). Continuous intravenous infusions of L-[ring-2H5]-phenylalanine and L-[1-13C]-leucine were applied with blood and muscle tissue samples collected throughout overnight sleep. Presleep protein ingestion did not increase muscle connective tissue protein synthesis rates (0.049 ± 0.013 vs. 0.060 ± 0.024%/hr in PLA and PRO, respectively; p = .73). Exercise plus protein ingestion resulted in greater overnight muscle connective tissue protein synthesis rates (0.095 ± 0.022%/hr) when compared with PLA and PRO (p < .01). Exercise increased the incorporation of dietary protein-derived amino acids into muscle connective tissue protein (0.036 ± 0.013 vs. 0.054 ± 0.009 mole percent excess in PRO vs. EX+PRO, respectively; p < .01). In conclusion, resistance-type exercise plus presleep protein ingestion increases overnight muscle connective tissue protein synthesis rates in older men. Exercise enhances the utilization of dietary protein-derived amino acids as precursors for de novo muscle connective tissue protein synthesis during overnight sleep.

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Timing and distribution of protein ingestion during prolonged recovery from resistance exercise alters myofibrillar protein synthesis

The Journal of Physiology ◽

10.1113/jphysiol.2012.244897 ◽

2013 ◽

Vol 591 (9) ◽

pp. 2319-2331 ◽

Cited By ~ 217

Author(s):

José L. Areta ◽

Louise M. Burke ◽

Megan L. Ross ◽

Donny M. Camera ◽

Daniel W. D. West ◽

...

Keyword(s):

Protein Synthesis ◽

Resistance Exercise ◽

Myofibrillar Protein ◽

Protein Ingestion ◽

Prolonged Recovery ◽

Myofibrillar Protein Synthesis

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Short-term muscle disuse lowers myofibrillar protein synthesis rates and induces anabolic resistance to protein ingestion

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.00227.2015 ◽

2016 ◽

Vol 310 (2) ◽

pp. E137-E147 ◽

Cited By ~ 57

Author(s):

Benjamin T. Wall ◽

Marlou L. Dirks ◽

Tim Snijders ◽

Jan-Willem van Dijk ◽

Mario Fritsch ◽

...

Keyword(s):

Protein Synthesis ◽

Muscle Protein ◽

Myofibrillar Protein ◽

Disuse Atrophy ◽

Short Term ◽

Anabolic Resistance ◽

Muscle Disuse ◽

Protein Ingestion ◽

The Impact ◽

Myofibrillar Protein Synthesis

Disuse leads to rapid loss of skeletal muscle mass and function. It has been hypothesized that short successive periods of muscle disuse throughout the lifespan play an important role in the development of sarcopenia. The physiological mechanisms underlying short-term muscle disuse atrophy remain to be elucidated. We assessed the impact of 5 days of muscle disuse on postabsorptive and postprandial myofibrillar protein synthesis rates in humans. Twelve healthy young (22 ± 1 yr) men underwent a 5-day period of one-legged knee immobilization (full leg cast). Quadriceps cross-sectional area (CSA) of both legs was assessed before and after immobilization. Continuous infusions of l-[ ring-2H5]phenylalanine and l-[1-13C]leucine were combined with the ingestion of a 25-g bolus of intrinsically l-[1-13C]phenylalanine- and l-[1-13C]leucine-labeled dietary protein to assess myofibrillar muscle protein fractional synthetic rates in the immobilized and nonimmobilized control leg. Immobilization led to a 3.9 ± 0.6% decrease in quadriceps muscle CSA of the immobilized leg. Based on the l-[ ring-2H5]phenylalanine tracer, immobilization reduced postabsorptive myofibrillar protein synthesis rates by 41 ± 13% (0.015 ± 0.002 vs. 0.032 ± 0.005%/h, P < 0.01) and postprandial myofibrillar protein synthesis rates by 53 ± 4% (0.020 ± 0.002 vs. 0.044 ± 0.003%/h, P < 0.01). Comparable results were found using the l-[1-13C]leucine tracer. Following protein ingestion, myofibrillar protein bound l-[1-13C]phenylalanine enrichments were 53 ± 18% lower in the immobilized compared with the control leg (0.007 ± 0.002 and 0.015 ± 0.002 mole% excess, respectively, P < 0.05). We conclude that 5 days of muscle disuse substantially lowers postabsorptive myofibrillar protein synthesis rates and induces anabolic resistance to protein ingestion.

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Hypoenergetic diet-induced reductions in myofibrillar protein synthesis are restored with resistance training and balanced daily protein ingestion in older men

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.00550.2014 ◽

2015 ◽

Vol 308 (9) ◽

pp. E734-E743 ◽

Cited By ~ 58

Author(s):

Caoileann H. Murphy ◽

Tyler A. Churchward-Venne ◽

Cameron J. Mitchell ◽

Nathan M. Kolar ◽

Amira Kassis ◽

...

Keyword(s):

Protein Synthesis ◽

Resistance Training ◽

Older Men ◽

Myofibrillar Protein ◽

Energy Restriction ◽

Protein Distribution ◽

Protein Meal ◽

Fed State ◽

Sarcoplasmic Protein ◽

Myofibrillar Protein Synthesis

Strategies to enhance weight loss with a high fat-to-lean ratio in overweight/obese older adults are important since lean loss could exacerbate sarcopenia. We examined how dietary protein distribution affected muscle protein synthesis during energy balance (EB), energy restriction (ER), and energy restriction plus resistance training (ER + RT). A 4-wk ER diet was provided to overweight/obese older men (66 ± 4 yr, 31 ± 5 kg/m2) who were randomized to either a balanced (BAL: 25% daily protein/meal × 4) or skewed (SKEW: 7:17:72:4% daily protein/meal; n = 10/group) pattern. Myofibrillar and sarcoplasmic protein fractional synthetic rates (FSR) were measured during a 13-h primed continuous infusion of l-[ ring-13C6]phenylalanine with BAL and SKEW pattern of protein intake in EB, after 2 wk ER, and after 2 wk ER + RT. Fed-state myofibrillar FSR was lower in ER than EB in both groups ( P < 0.001), but was greater in BAL than SKEW ( P = 0.014). In ER + RT, fed-state myofibrillar FSR increased above ER in both groups and in BAL was not different from EB ( P = 0.903). In SKEW myofibrillar FSR remained lower than EB ( P = 0.002) and lower than BAL ( P = 0.006). Fed-state sarcoplasmic protein FSR was reduced similarly in ER and ER + RT compared with EB ( P < 0.01) in both groups. During ER in overweight/obese older men a BAL consumption of protein stimulated the synthesis of muscle contractile proteins more effectively than traditional, SKEW distribution. Combining RT with a BAL protein distribution “rescued” the lower rates of myofibrillar protein synthesis during moderate ER.

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