Supplement redux: caffeine

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In the Jockology series on supplements, I’ve left out the one substance that is by far the clearest performance enhancer, as well as being the most widely used and most easily available: caffeine. That’s mainly because I covered that territory in a Jockology column all about caffeine back in September. Still, I’d be remiss not to mention it — especially in light of a solid article about caffeine’s ergogenic effects by Gina Kolata in today’s New York Times.

One point worth mentioning: Kolata doesn’t differentiate between pure caffeine and coffee. It’s true that many athletes drink a cup of coffee before every race or competition — but coffee has a long list of active ingredients that make its effects harder to predict, as University of Guelph researcher Terry Graham told me last fall:

Caffeine, however, is not the same thing as coffee. The only rigorous study directly comparing the effects of caffeine (in pill form) and coffee was performed in Dr. Graham’s lab. To their surprise, his team found that only pure caffeine produced a performance boost, even when the level of caffeine in the bloodstream from coffee was identical.

Other studies have found a performance-enhancing effect from coffee, so Dr. Graham is cautious about overstating his results. What is clear is that the effects of coffee, with its complex mix of bioactive ingredients, are far harder to nail down than the unambiguous effects of pure caffeine.