Does Caffeine Enhance Athletic Performance?
Aim: A plethora of studies have been conducted to examine the effect of caffeine on athletic performance, with conflicting results. The purpose of the study is to investigate the effects of caffeine on muscle activity, physical training, competitive sports events and short-term physical activity.
Methods: For the purpose of the research, a literature review was conducted to determine the optimal dosage of caffeine for athletes, and collected scientific evidence about the caffeine’s effect on athletic endurance. The inclusion criteria contain original articles with primary data collection, both quantitative and qualitative published research studies, and studies with athletic subjects. The exclusion criteria comprises review articles without outcome data, incorrect study type, studies with < 10 subjects, and studies with physical inactive subjects.
Results: An issue for dietitians and other sports medicine personnel is that all recommend that exercising athletes should avoid the use of caffeine because it is a diuretic, and that it may exacerbate dehydration and hyperthermia. Evidence indicates that consuming a moderate level of caffeine results in a mild increase of urine production. There is no evidence suggesting that moderate caffeine intake (<456 mg) induces chronic dehydration or negatively affects exercise performance. In addition, pre-exercise feeding may significantly affect plasma caffeine concentrations and the potential for caffeine to improve performance. On the other hand, recent studies suggest that caffeine might indeed have ergogenic potential in endurance events. Also, reports concerning caffeine’s effect on V̇O2 max and exercise performance during incremental exercise are not in agreement. However, few caffeine studies have been published to include cognitive and physiologic considerations for the athlete. Furthermore, the effects of different doses of caffeine play important role on endurance. In addition, exercise time to exhaustion seems to be different between users and nonusers with the ergogenic effect being greater and lasting longer in nonusers.
Conclusion: Caffeine consumption may enhance athletic endurance, based on strong evidence, but further research needs to be conducted. High caffeine doses than the optimal, 3-6 mg/kg, before exercise does not confer any additional improvement in athletic performance. Additional, higher caffeine doses may cause side effects in athletes.
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