A pre-race cup of coffee is as much part of the keen exercisers ergogenic arsenal as a bottle of Lucozade these days. But does caffeine really enhance sports performance, or is it all something of a storm in a, er, coffee cup?
The Java jury is still out but there have been some very interesting findings since caffeines performance-enhancing effect was first discovered in the 1970s. In a series of studies conducted at Ball State University, cycle time to exhaustion increased by 19.5% following caffeine intake. A whole batch of studies followed this initial experiment with mixed results.
The effects of caffeine on performance
Current researchers tend to suggest that caffeine almost certainly has an ergogenic influence in some people, in some forms of exercise. In other words, it isnt a magic bullet. But lets have a look at who might benefit and when.
The most compelling evidence regarding caffeines usefulness is in prolonged submaximal endurance exercise. For runners, that means your long and steady runs sessions in which you are exercising for a long time but not at your maximum effort. Workouts that do not use the persons maximum effort but last 40 minutes or more are also examples of prolonged submaximal endurance exercise.
There is less research on the effect of caffeine in multi-sprint sports, such as football and tennis although one study found that women who took caffeine prior to a four-hour tennis match won significantly more games compared to when they drank a carbohydrate drink or a placebo
And that brings us to an interesting point. While early researchers thought caffeines benefit came from its ability to help us spare muscle glycogen by increasing fat metabolism, current thinking is that it is caffeines effect on our brain, rather than the body, that really counts.
The fact that caffeine worked even better than carbohydrate in the tennis study may have been due to the caffeine having had a positive influence on the womens concentration, alertness and speed of reactions. And that idea is backed up by research that shows a beneficial effect on activities requiring a lot of concentration and fine motor skill, such as fencing, shooting and badminton. This shouldnt come as any surprise. Who hasnt used a strong cup of coffee to blow away fogginess and waning focus?
It seems that the caffeine effect isnt restricted to sharpening mental skills, either; it also appears to make exercise easier by preventing the rise in neurotransmitters associated with fatigue during exercise so that you simply dont feel tired. For example, in one study cyclists were able to maintain a higher intensity of effort over a two-hour period after caffeine intake, but their perception of effort (RPE) stayed the same. In other words, they were working harder but didnt feel as if they were.
Before you go off to fill your sports bottle with cold espresso, bear in mind that the amount of caffeine-induced performance enhancement you are likely to get depends, in part, on your caffeine sensitivity. Starbucks addicts are less likely to get a performance kick than people who only rarely partake in a cappuccino. Then again, if you arent accustomed to caffeine, you may find that it upsets your stomach so it isnt something to experiment with prior to an important race or training session.