Physiological and Performance Effects of Adding Branched-Chain Amino Acids to a High Carbohydrate Formula Diet during Exercise

高醣配方飲食添加支鏈胺基酸對運動之生理影響

湯馥君(Fu-Chun Tang) ； 李志文(Chih-Wen Lee) ； 謝伸裕(Shen-Yu Hsieh)

《中華民國營養學會雜誌》 22卷4期 (1997/11) Pp. 361-371

https://doi.org/10.6691/JCNS.199711_22(4).0001

摘要

Previous study found that plasma branched-chain amino acid (BCAA) concentrations were significantly decreased after 7 days of low/moderate aerobic exercise. To understand the physiological homeostasis of adding BCAAs to the carbohydrate (CHO) diet which is believed to enhance exercise performance, the present double blind and crossover study was undertaken. Nineteen male college athletes, randomly divided into 2 groups: placebo and BCAAs (2.2 g), were employed and, in the postabsorptive state, all received a high CHO (~84%) formula diet (~13 kcal/kg BW) 1 hour before an exhaustion exercise program 85% maximal oxygen consumption [VO(subscript 2max)), 10% grade). Blood samples were taken before, during, and after the exercise program. The exhaustion was determined by the measurements of maximal heart rate (HRmax), respiratory exchange ratio (RER), and plasma lactate concentration. The plasma BCAA concentrations were significantly lower (p＜0.05) and the ratios of f-tryptophan/BCAAs were significantly higher (p＜0.05) in the placebo group than those in the BCAAs group, measured at the same time interval. During the exercise, the BCAA concentrations, both the individual and total, in the placebo group decreased significantly (p＜0.05) whereas those of the BCAAs group remained constant. Exercise time to exhaustion was shorter in subjects receiving placebo although the difference did not reach a significant level (p=0.43). No differences in body weight changes, HRmax, VO(subscript 2max), and RER were observed between the two groups nor in the plasma lactate concentrations measured at the same time interval. The results suggest that BCAAs supplements tend to increase exercise endurance.

關鍵字

支鏈胺基酸 ； 醣類 ； 運動

並列摘要

Previous study found that plasma branched-chain amino acid (BCAA) concentrations were significantly decreased after 7 days of low/moderate aerobic exercise. To understand the physiological homeostasis of adding BCAAs to the carbohydrate (CHO) diet which is believed to enhance exercise performance, the present double blind and crossover study was undertaken. Nineteen male college athletes, randomly divided into 2 groups: placebo and BCAAs (2.2 g), were employed and, in the postabsorptive state, all received a high CHO (~84%) formula diet (~13 kcal/kg BW) 1 hour before an exhaustion exercise program 85% maximal oxygen consumption [VO(subscript 2max)), 10% grade). Blood samples were taken before, during, and after the exercise program. The exhaustion was determined by the measurements of maximal heart rate (HRmax), respiratory exchange ratio (RER), and plasma lactate concentration. The plasma BCAA concentrations were significantly lower (p＜0.05) and the ratios of f-tryptophan/BCAAs were significantly higher (p＜0.05) in the placebo group than those in the BCAAs group, measured at the same time interval. During the exercise, the BCAA concentrations, both the individual and total, in the placebo group decreased significantly (p＜0.05) whereas those of the BCAAs group remained constant. Exercise time to exhaustion was shorter in subjects receiving placebo although the difference did not reach a significant level (p=0.43). No differences in body weight changes, HRmax, VO(subscript 2max), and RER were observed between the two groups nor in the plasma lactate concentrations measured at the same time interval. The results suggest that BCAAs supplements tend to increase exercise endurance.

並列關鍵字

branched-chain amino acids ； carbohydrate ； exercise