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Visa fullständig version : Effekt av kolhydrat- BCAA & koffein på prestation och neuromuskulär funktion


King Grub
2011-12-14, 12:02
Background

Carbohydrates (CHOs), branched-chain amino acids (BCAAs) and caffeine are known to improve running performance. However, no information is available on the effects of a combination of these ingredients on performance and neuromuscular function during running.

Methods

The present study was designed as a randomized double-blind cross-over placebo-controlled trial. Thirteen trained adult males completed two protocols, each including two conditions: placebo (PLA) and Sports Drink (SPD: CHOs 68.6 g.L-1, BCAAs 4 g.L-1, caffeine 75 mg.L-1). Protocol 1 consisted of an all-out 2 h treadmill run. Total distance run and glycemia were measured. In protocol 2, subjects exercised for 2 h at 95% of their lowest average speeds recorded during protocol 1 (whatever the condition). Glycemia, blood lactate concentration and neuromuscular function were determined immediately before and after exercise. Oxygen consumption ( VO2), heart rate (HR) and rate of perceived exertion (RPE) were recorded during the exercise. Total fluids ingested were 2 L whatever the protocols and conditions.

Results

Compared to PLA, ingestion of SPD increased running performance (p=0.01), maintained glycemia and attenuated central fatigue (p=0.04), an index of peripheral fatigue (p=0.04) and RPE (p=0.006). Maximal voluntary contraction, VO2, and HR did not differ between the two conditions.

Conclusions

This study showed that ingestion of a combination of CHOs, BCAAs and caffeine increased performance by about 2% during a 2-h treadmill run. The results of neuromuscular function were contrasted: no clear cut effects of SPD were observed.

Effects of carbohydrates-BCAAs-caffeine ingestion on performance and neuromuscular function during a 2-h treadmill run: a randomized, double-blind, cross-over placebo-controlled study. J Int Soc Sports Nutr. 2011 Dec 7;8(1):22

http://www.jissn.com/content/pdf/1550-2783-8-22.pdf