The intake of whey, compared with casein and soy protein intakes, stimulates a greater acute response of muscle protein synthesis (MPS) to protein ingestion in rested and exercised muscle. We characterized the dose-response relation of postabsorptive rates of myofibrillar MPS to increasing amounts of whey protein at rest and after exercise in resistance-trained, young men. Volunteers (n = 48) consumed a standardized, high-protein (0.54 g/kg body mass) breakfast. Three hours later, a bout of unilateral exercise (8 × 10 leg presses and leg extensions; 80% one-repetition maximum) was performed. Volunteers ingested 0, 10, 20, or 40 g whey protein isolate immediately (~10 min) after exercise. Postabsorptive rates of myofibrillar MPS and whole-body rates of phenylalanine oxidation and urea production were measured over a 4-h postdrink period by continuous tracer infusion of labeled [(13)C6] phenylalanine and [(15)N2] urea. Myofibrillar MPS (mean ± SD) increased (P < 0.05) above 0 g whey protein (0.041 ± 0.015%/h) by 49% and 56% with the ingestion of 20 and 40 g whey protein, respectively, whereas no additional stimulation was observed with 10 g whey protein (P > 0.05). Rates of phenylalanine oxidation and urea production increased with the ingestion of 40 g whey protein. A 20-g dose of whey protein is sufficient for the maximal stimulation of postabsorptive rates of myofibrillar MPS in rested and exercised muscle of ~80-kg resistance-trained, young men. A dose of whey protein >20 g stimulates amino acid oxidation and ureagenesis. This trial was registered at http://www.isrctn.org/ as ISRCTN92528122.

The purpose of this study was to examine the role of branched-chain amino acid (BCAA) supplementation during recovery from intense eccentric exercise. Twenty-four non-weight-trained males were assigned to one of two groups: one group (supplementary, SUP) ingested BCAA beverages (n = 12); the second group (placebo, PLA) ingested artificially flavored water (n = 12). Diet was controlled throughout the testing period to match habitual intake. The eccentric exercise protocol consisted of 12 x 10 repetitions of unilateral eccentric knee extension exercise at 120% concentric one repetition maximum. On the day of the exercise, supplements were consumed 30 min before exercise, 1.5 h after exercise, between lunch and dinner, and before bed. On the following 2 d, four supplements were consumed between meals. Muscle soreness, muscle function, and putative blood markers of muscle damage were assessed before and after (1, 8, 24, 48, and 72 h) exercise. Muscle function decreased after the eccentric exercise (P < 0.0001), but the degree of force loss was unaffected by BCAA ingestion (51% +/- 3% with SUP vs -48% +/- 7% with PLA). A decrease in flexed muscle soreness was observed in SUP compared with PLA at 48 h (21 +/- 3 mm vs 32 +/- 3 mm, P = 0.02) and 72 h (17 +/- 3 mm vs 27 +/- 4 mm, P = 0.038). Flexed muscle soreness, expressed as area under the curve, was lower in SUP than in PLA (P = 0.024). BCAA supplementation may attenuate muscle soreness, but it does not ameliorate eccentric exercise-induced decrements in muscle function or increases in reputed blood markers of muscle damage, when consumed before exercise and for 3 d after an eccentric exercise bout.

The ingestion of intact protein or essential amino acids (EAA) stimulates mechanistic target of rapamycin complex-1 (mTORC1) signaling and muscle protein synthesis (MPS) following resistance exercise. The purpose of this study was to investigate the response of myofibrillar-MPS to ingestion of branched-chain amino acids only (i.e., without concurrent ingestion of other EAA, intact protein or other macronutrients) following resistance exercise in humans. Ten young (20.1 ± 1.3 y), resistance-trained men completed two trials, ingesting either 5.6g branched-chain amino acid (BCAA) or a placebo (PLA) drink immediately after resistance exercise. Myofibrillar-MPS during exercise recovery was measured with a primed, constant infusion of L-[ring13C6] phenylalanine and collection of muscle biopsies pre and 4h post drink ingestion. Blood samples were collected at time-points before and after drink ingestion. Western blotting was used to measure the phosphorylation status of mTORC1 signaling proteins in biopsies collected pre, 1h- and 4h-post drink. The percentage increase from baseline in plasma leucine (300 ± 96%), isoleucine (300 ± 88%) and valine (144 ± 59%) concentrations peaked 0.5h-post drink in BCAA. A greater phosphorylation status of S6K1Thr389 (P=0.012) and PRAS40 (P=0.043) was observed in BCAA than PLA at 1h post drink ingestion. Myofibrillar-MPS was 22% higher (P=0.012) in BCAA (0.110 ± 0.009 %/h) than PLA (0.090 ± 0.006 %/h). Phenylalanine Ra was ~6% lower in BCAA (18.00 ± 4.31 μmol·kgBM-1) than PLA (21.75 ± 4.89 μmol·kgBM-1; P=0.028) after drink ingestion. We conclude that ingesting branched-chain amino acids alone increases the post-exercise stimulation of myofibrillar-MPS and phosphorylation status mTORC1 signaling.

The present study investigated the fitness and health effects of medium-term soccer training for untrained hypertensive middle-age men. Thirty-three untrained males (31–54 yr) with mild-to-moderate hypertension were randomized 2:1 to a soccer training group (STG, two 1-h sessions per week, n = 22, 68% on medication) and a doctor advice group receiving traditional physician-guided recommendations on cardiovascular risk factor modification (DAG, n = 11, 73% on medication). Two-way repeated-measures ANOVA time–group statistics was applied. During soccer training, average HR was 155 ± 9 bpm or 85% ± 7% HRmax. In STG, systolic and diastolic blood pressures decreased (P < 0.01) over 6 months from 151 ± 10 to 139 ± 10 mm Hg and from 92 ± 7 to 84 ± 6 mm Hg, respectively, with smaller (P < 0.05) decreases in DAG (from 153 ± 8 to 145 ± 8 mm Hg and from 96 ± 6 to 93 ± 6 mm Hg, respectively). In STG, V˙O2max increased (P < 0.01) from 32.6 ± 4.9 to 35.4 ± 6.6 mL·min−1·kg−1 and relative V˙O2 during cycling at 100 W was lowered (P < 0.05) from 55% ± 7% to 50% ± 8% V˙O2max over 6 months, with no changes in DAG. In STG, resting HR was lowered by 8 ± 11 bpm (P < 0.05), and the augmentation index (a measure of arterial stiffness) was lowered (P < 0.05) by 7.3 ± 14.0 over 6 months, with no change in DAG. Six months of soccer training improved aerobic fitness, reduced blood pressure, and resulted in an array of other favorable effects on cardiovascular risk profile for untrained middle-age hypertensive men. Soccer training, therefore, may be a better nonpharmacological treatment for hypertensive men than traditional physician-guided advice.