Exercise endurance, caffeine, effects

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

Perhaps the most intriguing perspective is that caffeine s major effects have little to do with muscles and fat metabolism but result from its psychostimulant effects, enhancing mood, improving attitude towards exercise, and thus motivating athletes to work harder and longer. This would account for its purported inability to alter strength, which may be a less psychologically malleable variable, while endurance performance is sometimes believed to be more amenable to force of will. 

Cadarette, B., Levine, L., Berube, C., Posner, B., and Evans, W., Effects of varied doses of caffeine on endurance exercise to fatigue, Biochemistry of Exercise, 13, 871, 1983. 

Butts, N. and Crowell, O., Effects of caffeine ingestion on cardiorespiratory endurance in men and women, Research Quarterly in Exercise and Sports, 56, 301, 1985. 

A number of studies have shown that caffeine may favorably affect long-term endurance performance (ref.3) but research results concerning high intensity, short-term exercise have been a bit mixed (ref.4). Still, it seems very likely from an analysis of the biochemical effects of caffeine that is has a beneficial effect on short-term fatigue and muscle fiber in high intensity, short-term exercise like weightlifting (ref.5 6). 

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