Caffeine ergogenic effects

VII. Summary of Caffeine s Effects as an Ergogenic Aid A. Muscular Strength... 

Despite the apparent promise for this line of research to explain caffeine s potential ergogenicity, the doses of caffeine necessary to produce significant calcium shifts are midway between toxic and lethal levels when transposed to in vitro situations.5 These dosage requirements suggest that the mobilization of intracellular calcium is not a viable explanation for caffeine s potential ergogenic effects in live human subjects. 

The most promising mechanism of action, which may account for some of caffeine s potential ergogenic effects, involves its demonstrated ability as a competitive antagonist of the depressant effects of adenosine analogs in the central nervous system. Adenosine and its derivatives have been shown to inhibit neuronal electrical activity, the release of neurotransmitters, and to interfere with synaptic transmission.19-24 27... 

In their study of untrained vs. trained swimmers, Collomp et al.40 suggested that specific training may be the catalyst that stimulates caffeine s ergogenic effects during high intensity, anaerobic activity. The results of many studies have also suggested that only well-trained athletes derive significant benefits from caffeine due to the athletes previously stimulated lipolytic activity and the increased size and density of their mito-chondria.40-52-58-59... 

Finally, there is virtually no mention of the fact that the majority of test subjects in the caffeine research literature are reported to be males, so that hormonal differences in respect to caffeine s ergogenic effects may be a topic that requires further examination. 

Such results suggest a need for further research comparing trained with untrained subjects, along with an examination of muscle fiber type ratios of experimental subjects. Also, the question of subjects habituation to caffeine needs to be explored more fully. For the present, the reported ergogenic effects of caffeine on muscular strength must be viewed with skepticism and perhaps be attributed to the psychostimulant properties of caffeine. 

In the case of caffeine s ergogenic effects on endurance during extended exercise of submaximal intensity (70 to 85% V02 max), animal... 

Graham et al.79 noted that more than a quarter of Canadian youth surveyed reported use of caffeine during the last year to improve their athletic performance. The current allowable levels of caffeine permitted by the IOC are well above the minimum dose needed to elicit an ergogenic effect. If the IOC and other regulatory bodies are serious about controlling the use of performance enhancing drugs, then it may be necessary to ban caffeine entirely from competition. 

Jacobson, B. H. and Kulling, F. A., Health and ergogenic effects of caffeine, British Journal of Sports Medicine, 23, 34, 1989. 

Bell DG, Jacobs I, McLellan TM, Zamecnik J. Reducing the dose of combined caffeine and ephedrine preserves the ergogenic effect. Aviat Space Environ Med 2000 71 (4) 415—419. 

Somewhat of a dichotomy exists in the research literature pertaining to caffeine s ergogenic potential to enhance short-term, intense exercise. In general, laboratory research (in vitro/in situ) has consistently demonstrated positive results related to caffeine s ability to generate increased muscular force. Human studies have consistently been suggestive of no significant effects on short-term, high intensity performance. There have been a... 

A series of studies conducted in the late 1970s at Ball State University s Human Performance Laboratory by Costill and associates6163 has established caffeine as an effective ergogenic aid for the enhancement of endur-... 

Caffeine is widely used as an ergogenic aid by competitive athletes and weekend warriors alike (90), but its effects appear to be variable depending on the... 

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