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Nitro Speed · 30-08-09, 22:49

והנה קטע על תיסוף BCAA
The anabolic hormone response to a lower-body resistance exercise bout in conjunction with oral BCAA supplementation

1University of South Florida – Exercise and Performance Nutrition Laboratory, Tampa, FL, USA
2Baylor University – Exercise and Biochemical Nutrition Laboratory, Waco, TX, USA
3Texas A&M University – Exercise and Sport Nutrition Laboratory, College Station, TX, USA

from 2009 International Society of Sports Nutrition Conference and Expo
New Orleans, LA, USA. 14–15 June 2009

Journal of the International Society of Sports Nutrition 2009, 6(Suppl 1):P7doi:10.1186/1550-2783-6-S1-P7

Published: 31 July 2009

© 2009 Campbell et al; licensee BioMed Central Ltd.

Background

BCAAs (leucine, isoleucine, and valine), particularly leucine, activate key enzymes in protein synthesis after physical exercise. Research has demonstrated that BCAAs increase mTOR phosphorylation and activate p70 S6 kinase in human muscle via an Akt-independent pathway. The extent to which BCAAs influence the anabolic hormone response in conjunction with resistance exercise is not well established. A randomized, double-blind, placebo-controlled study was performed to evaluate the effects of BCAA ingestion in conjunction with an acute bout of lower-body resistance exercise (RE) on various anabolic hormones.

Methods

20 recreationally active males ingested a BCAA supplement (120 mg/kg/bw) (n = 10; 24.4 years; 178.3 cm; 85.4 kg) or a placebo (n = 10; 21 years; 176.8 cm; 83 kg) at 3 time points: 30 minutes prior to RE, and immediately pre-RE and immediately post-RE. Subjects performed 4 sets of leg press and 4 sets of leg extension at 80% 1 RM to failure. Rest periods between sets and exercises was approximately 150 seconds. Venous blood was sampled at baseline; 30 min later, immediate postexercise, 30 min post-exercise; 2 hrs post-exercise, and 6 hrs post-exercise for serum insulin, growth hormone (GH), and free insulin-like growth factor-1 (IGF-1). A two-way ANOVA with repeated measures was utilized to analyze the data.

Results

Data are reported as means ± SD at baseline; 30 min later, immediate postexercise, 30 min post-exercise; 2 hrs post-exercise, and 6 hrs post-exercise. Insulin values were 19.2 ± 7.8, 23.0 ± 9.6, 25.3 ± 12.9, 24.8 ± 14.3, 19.0 ± 9.0, 15.8 ± 6.4 and 22.0 ± 10.5, 22.0 ± 10.9, 27.8 ± 9, 24.1 ± 8.7, 17.9 ± 8.8, 21.2 ± 12.8 uIU/mL for the BCAA and Placebo groups, respectively. A significant main effect for time was observed (p < .001), but no significant main effect for group (p = .758) or significant interaction (p = .465) was observed for insulin. GH values were .41 ± .81, .64 ± .97, 1.9 ± 2.2, 1.5 ± 2.6, .23 ± .32, 2.6 ± 4.0 and .07 ± .09, .84 ± 1.3, 2.2 ± 1.9, 2.2 ± 3.8, .28 ± .76, .36 ± .56 ng/ml for the BCAA and Placebo groups, respectively. A significant main effect for time was observed (p = .021), but no significant main effect for group (p = .672) or significant interaction (p = .217) was observed for GH. Free IGF-1 values were 1.3 ± .83, 1.2 ± .72, 1.2 ± .77, 1.4 ± .91, 1.1 ± .74, .95 ± .64 and 1.3 ± .43, 1.2 ± .43, 1.6 ± .54, 1.5 ± .57, 1.4 ± .46, 1.1 ± .53 ng/ml for the BCAA and Placebo groups, respectively. A significant main effect for time was observed (p = .014), but no significant main effect for group (p = .569) or significant interaction (p = .356) was observed for free IGF-1.

Conclusion

An acute bout of lower-body RE significantly increases insulin, GH, and IGF-1 in the immediate post-exercise time period, but oral ingestion of BCAA at a dosage of 120 mg/kg/bw does not impart an additional effect of the hormonal response to the resistance exercise stimulus.

30-08-09, 22:49	#10
Nitro Speed חבר פעיל תאריך הצטרפות: May 2009 צפה באלבומי התמונות של Nitro Speed הודעות: 1,678	והנה קטע על תיסוף BCAA The anabolic hormone response to a lower-body resistance exercise bout in conjunction with oral BCAA supplementation 1University of South Florida – Exercise and Performance Nutrition Laboratory, Tampa, FL, USA 2Baylor University – Exercise and Biochemical Nutrition Laboratory, Waco, TX, USA 3Texas A&M University – Exercise and Sport Nutrition Laboratory, College Station, TX, USA from 2009 International Society of Sports Nutrition Conference and Expo New Orleans, LA, USA. 14–15 June 2009 Journal of the International Society of Sports Nutrition 2009, 6(Suppl 1):P7doi:10.1186/1550-2783-6-S1-P7 Published: 31 July 2009 © 2009 Campbell et al; licensee BioMed Central Ltd. Background BCAAs (leucine, isoleucine, and valine), particularly leucine, activate key enzymes in protein synthesis after physical exercise. Research has demonstrated that BCAAs increase mTOR phosphorylation and activate p70 S6 kinase in human muscle via an Akt-independent pathway. The extent to which BCAAs influence the anabolic hormone response in conjunction with resistance exercise is not well established. A randomized, double-blind, placebo-controlled study was performed to evaluate the effects of BCAA ingestion in conjunction with an acute bout of lower-body resistance exercise (RE) on various anabolic hormones. Methods 20 recreationally active males ingested a BCAA supplement (120 mg/kg/bw) (n = 10; 24.4 years; 178.3 cm; 85.4 kg) or a placebo (n = 10; 21 years; 176.8 cm; 83 kg) at 3 time points: 30 minutes prior to RE, and immediately pre-RE and immediately post-RE. Subjects performed 4 sets of leg press and 4 sets of leg extension at 80% 1 RM to failure. Rest periods between sets and exercises was approximately 150 seconds. Venous blood was sampled at baseline; 30 min later, immediate postexercise, 30 min post-exercise; 2 hrs post-exercise, and 6 hrs post-exercise for serum insulin, growth hormone (GH), and free insulin-like growth factor-1 (IGF-1). A two-way ANOVA with repeated measures was utilized to analyze the data. Results Data are reported as means ± SD at baseline; 30 min later, immediate postexercise, 30 min post-exercise; 2 hrs post-exercise, and 6 hrs post-exercise. Insulin values were 19.2 ± 7.8, 23.0 ± 9.6, 25.3 ± 12.9, 24.8 ± 14.3, 19.0 ± 9.0, 15.8 ± 6.4 and 22.0 ± 10.5, 22.0 ± 10.9, 27.8 ± 9, 24.1 ± 8.7, 17.9 ± 8.8, 21.2 ± 12.8 uIU/mL for the BCAA and Placebo groups, respectively. A significant main effect for time was observed (p < .001), but no significant main effect for group (p = .758) or significant interaction (p = .465) was observed for insulin. GH values were .41 ± .81, .64 ± .97, 1.9 ± 2.2, 1.5 ± 2.6, .23 ± .32, 2.6 ± 4.0 and .07 ± .09, .84 ± 1.3, 2.2 ± 1.9, 2.2 ± 3.8, .28 ± .76, .36 ± .56 ng/ml for the BCAA and Placebo groups, respectively. A significant main effect for time was observed (p = .021), but no significant main effect for group (p = .672) or significant interaction (p = .217) was observed for GH. Free IGF-1 values were 1.3 ± .83, 1.2 ± .72, 1.2 ± .77, 1.4 ± .91, 1.1 ± .74, .95 ± .64 and 1.3 ± .43, 1.2 ± .43, 1.6 ± .54, 1.5 ± .57, 1.4 ± .46, 1.1 ± .53 ng/ml for the BCAA and Placebo groups, respectively. A significant main effect for time was observed (p = .014), but no significant main effect for group (p = .569) or significant interaction (p = .356) was observed for free IGF-1. Conclusion An acute bout of lower-body RE significantly increases insulin, GH, and IGF-1 in the immediate post-exercise time period, but oral ingestion of BCAA at a dosage of 120 mg/kg/bw does not impart an additional effect of the hormonal response to the resistance exercise stimulus.