Abstract des Autors

Purpose: To determine if the macronutrient composition of a postexercise beverage would alter muscle anabolism and/or catabolism following resistance exercise. Methods: We provided isoenergetic CHO (1 g/kg) and CHO/PRO/FAT supplements and placebo (PL) immediately (t = 0 h) and 1 h (t = +1 h) following resistance exercise (9 exercises/3 sets/80% 1 RM) to 10 young, healthy, resistance-trained males. Whole body leucine turnover was determined from L-[1-13C]leucine kinetics at ca. 4 h postexercise. Results: No differences were observed for urinary 3-methylhistidine or urea nitrogen excretion between the trials. Leucine flux was significantly elevated at ca. 4 h postexercise for both CHO/PRO/FAT (177.59+/-12.68 micro-mol/kg/h) and CHO (156.18+/-7.77 micro-mol/kg/h) versus PL (126.32+/-10.51 micro-mol/kg/h) (P<0.01). Whole body leucine oxidation was elevated at ca. 4 h for CHO/PRO/FAT (29.50+/-3.34 micro-mol/kg/h) versus CHO (16.32+/-2.33 micro-mol/kg/h) (P<0.01) and PL (21.29+/-2.54 micro-mol/kg/h) (P<0.05). Nonoxidative leucine disposal (NOLD) was significantly elevated at ca. 4 h for both CHO/PRO/FAT (148.09+/-10.37 micro-mol/kg/h) and CHO (139.86+/-7.02 micro-mol/kg/h) versus PL (105.03+/-8.97 micro-mol/kg/h) (P<0.01). Conclusions: These results suggest that consumption of either CHO or CHO/PRO/FAT immediately and 1 h following a resistance training bout increased NOLD as compared with a placebo. Verf.-Referat