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Combination of Carbohydrate, BCAAs & Caffeine Enhances Endurance Exercise

Posted on Friday, 9 December, 2011 by anthony

Carbohydrates, BCAAs and Caffeine Enhance Endurance Exercise Performance

A recent study published in the Journal of the International Society of Sports Nutrition (Peltier et al., 2011) found that the consumption of a sports drink containing a combination of carbohydrates, branched chain amino acids (BCAAs) and Caffeine significantly increased running performance during a 2-hour treadmill run. The sports drink also helped to maintain glycemia (blood glucose) whilst significantly decreasing the rate of perceived exertion (RPE) and central fatigue compared with the placebo drink.

Why did the researchers look at the combined effects of Carbohydrates, Caffeine and BCAAs?

Previous studies have demonstrated that carbohydrate and caffeine ingestion can improve/prolong endurance exercise performance, and it has also been suggested that BCAA consumption may also have positive effects on endurance exercise performance. Both carbohydrate and caffeine consumption before and during exercise can help to preserve muscle glycogen levels, caffeine consumption can also increase fat metabolism and decrease central fatigue and the rate of perceived exertion (RPE), whilst BCAA consumption can decrease the rate of muscle breakdown, may preserve muscle glycogen, and has been postulated to reduce central fatigue. However, no previous studies have looked at the combined effects of carbohydrates, caffeine, and BCCAs on endurance exercise performance.

What Did The Researchers Find?

The researchers found that the consumption of 2litres of sports drink (Energy = 1254kJ/l, Carbohydrate = 68.6 g/l, BCAAs = 4 g/l, and caffeine = 75 mg/L) before (250ml 15 minutes before exercise) and during exercise (250ml every 15 minutes of exercise) significantly improved performance (by 1.9%) compared with the consumption of 2litres of placebo drink (Energy = 50KJ/l). Whilst the 1.9% doesn’t sound like a significant difference it equated to an average difference of 410 meters over the 2 hours. Based on the distance covered by the two groups, 22.31 ± 1.85 km for the sports drink group vs. 21.90 ± 1.69 km for the placebo drink group, we can calculate that the placebo group were approximately 2 mins and 15 seconds behind the sports drink group. The researchers hypothesized that the improvement seen in the sports drink group may have been limited because the subjects were not fasted (overnight) and therefore initial muscle glycogen levels were high. However, by not fasting overnight the improvement is likely to more accurately reflect the beneficial effects of the sports drink over the placebo since most athletes will carbo-load prior to a prolonged endurance event to ensure muscle glycogen levels are maximized.

The researchers also found that the sports drink reduced central fatigue and RPE. However, it wasn’t possible for the researchers to establish the individual contribution of each of the main ingredients on central fatigue or RPE. Since it is already known that both carbohydrate and caffeine consumption can improve endurance it is not clear whether the addition of BCAA to sports drink further enhanced performance or reduced central fatigue beyond that of carbohydrate and caffeine consumption alone.

In Summary:

The consumption of sports drink containing carbohydrate, BCAAs and caffeine before and during exercise is beneficial to performance during prolonged endurance exercise. It wasn’t clear what the contribution of each was to the improved exercise performance. It is already established that both carbohydrate and caffeine can enhance endurance exercise performance but the effect of BCAAs is less clear. However, since BCAAs will not negatively impact performance and have been shown to reduce post exercise muscle breakdown it seems logical to include them in any sports drink either during training or competition.

Full Composition of The Sports Drink

Full Composition of The Sports Drink: maltodextrin 31.6g/l, dextrose 24.2 g/l, fructose 12.8g/l, BCAAs 4g/l, curcumin 250mg/l, piperine 2.6mg/l, caffeine 75mg/l, sodium 884mg/l, magnesium 100mg/l, zinc 5mg/l, Vitamin C 15mg/l, Vitamin E 5mg/l, Vitamin B1 0.7mg/l, Vitamin B2 0.4 mg/l, Vitamin B3 9mg/l.

Reference

Peltier S L, Vincent L, Millet G Y, Sirvent P, Morin J-B, Guerraz M, Geyssan A, Lescuyer J-F, Feasson L and Messonnier L. (2011) 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.Journal of the International Society of Sports Nutrition 2011, 8:22

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