Q. I am a cyclist and would like to know whether drinking coffee before a ride can improve my performance. I can?t seem to get a straight answer about this. Does coffee help or not?
A. Coffee (that is, the caffeine in the coffee) may improve performance in cycling and other endurance sports. For example, laboratory studies of well-trained cyclists, conducted at the US Olympic Training Center in Colorado, have shown that drinking about 12 ounces of regular brew coffee (330-450 mg of caffeine) one hour before exercise increased riding time-to-exhaustion by as much as 25 percent.
However, more than this amount of caffeine is apparently not better. Higher doses provided no additional benefit. This is important to Olympic athletes. The use of large amounts of caffeine is banned in international competition, and the amount found effective in these studies does not exceed the acceptable level.
The Caffeine Effect. Here's what happens. When you cycle at a moderate pace for an extended period of time about half of the fuel for your muscles comes from glycogen (carbohydrates). The remainder comes from fat. But as the time or the pace of the activity increases, your muscles begin to rely much more on glycogen and much less on fat for fuel. Unfortunately, your body?s glycogen stores are in short supply compared to fat. So, after about an hour or two of exercise, your readily available glycogen supplies abruptly run out. And you "hit-the-wall." You can go no further.
Consuming coffee before the exercise helps here. Caffeine stimulates an increased use of fat as fuel during the exercise. This decreases your reliance on glycogen. Glycogen is conserved or "spared." And you can cycle longer and harder before exhaustion.
Other Considerations. This caffeine boost sounds good, but as with any performance enhancing substance, there are other considerations:
The whopping 25% increase in cycling riding time cited above comes from laboratory studies of well-trained athletes. The actual effect of caffeine on real life, open road cycling is not known.
The caffeine effect depends on how much you habitually consume, or your tolerance for the drug. People who regularly drink two or more cups of caffeinated coffee a day may have to abstain from the stimulus for four or five days for the caffeine to help improve their performance.
The timing of the caffeine intake can make a difference. Benefits appear to be highest when consumed immediately prior to exercise.
Caffeine is a diuretic. Diuretics interfere with the kidney action by reducing the reabsorption of needed water and salts back into the blood. Diuretics can also increase urination. In either case, the body's water and salt levels go down. This can lead to dehydration, heat illness, and muscle weakness. If you consume caffeine before cycling, increase your water consumption during the activity.
Caffeine can irritate the stomach, particularly if you are not used to it. And for some neophyte coffee drinkers, caffeine can produce "coffee nerves"--nervous tension, trembling, irritability, headaches, sluggishness, anxiety, and insomnia.
Caffeine has not been shown to improve performance during short, intense activities, such as weight training or running and swimming sprints.
End Note: Caffeine is widely consumed in other ways besides in coffee. But coffee has by far the highest caffeine content (110-150 mg. per 5 oz. cup). Soft drinks have much less (35-54 mg. per 12 oz.), and tea even less (9-50 mg. per 5 oz. cup, depending on brewing time). There are also small amounts of caffeine in chocolate, over-the-counter pain relievers, and cold remedies.