22 Eylül 2012 Cumartesi

Ergogenic Aids: Worth the hype?

You’ve trained for months, the race is quickly approaching. Physically you are ready, mentally you are prepared, and emotionally you are motivated to do your best during the race. But you hear of ergogenic aids or supplements that claim to help you “reach your peak performance” or “give you the cutting edge on the competition”. The supplements also claim to make you move faster, be stronger, and last longer during an endurance event. So if the label says it will help improve performance…it must really help, right? Sometimes ergogenic aids or supplements are beneficial and sometimes they are not and can even be dangerous. Researchers have studied the effects and mechanisms of many supplements claiming to be beneficial and here are a few results of commonly studied supplements:
Caffeine: Caffeine is a mild central nervous system stimulant that has been shown to improve performance. It helps increase mental sharpness and alertness while decreasing fatigue. Caffeine absorption occurs rapidly and its effects are felt within 30-45 minutes of ingestion and furthermore, have secondary effects a few hours after consumption which leads to greater improvement in endurance events. Several studies have concluded that a caffeine dose of 1.0-2.0 mg per kg of body weight is sufficient for positive results. Approximately, 1 cup of coffee contains 100-150 mg of caffeine, 1 cup of green tea contains 25-40 mg of caffeine, and 50 mg of dark chocolate contains 20-40 mg of caffeine.
Creatine: Creatine has shown to have many exercise-improving benefits as well, including increasing strength, improving short-term exercise performance, helping with recovery, and promoting lean body mass. Therefore, creatine is best for short-intense exercise and has not been shown to benefit long-term endurance exercise. Studies have concluded that optimal creatine loading is 5g/4 times a day for 4-5 days or 3g/day for 30 days.
Branched Chain Amino Acids (BCAA): Branched chain amino acids, isoleucine, leucine, and valine, have been shown to improve endurance but does not necessarily prevent fatigue. The BCAA may also play a role in immune function.
Beta-Alanine: Beta-alanine has been claimed to improve high intensity exercise but there is a lack of research to support this claim.

References
Keisler BD, Armsey TD. Caffeine as an ergogenic aid. ACSM. 2006: 5(4):215-219.


“Supplements and Ergogenic Aids for Athletes”.<http://www.eatright.org/Public/content.aspx?id             =7088&terms=fat+burning+foods>. Accessed 8 January 2012.
Tarnopolsky MA. Caffeine and creatine use in sport. Ann Nutr Metab 2010;57(2):1–8.
Stephanie Bailey - Dietetic Intern - University of Memphis

BIOMechaniks: Train the mind and the body will follow

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