We’re not sure if Usain Bolt likes to down an iced latte before a big race, but recent studies show that caffeine does have a measurable effect on athletic performance. Many athletes, from runners to bike racers, like to consume caffeinated drinks before an event for this reason. The exact way caffeine improves performance isn’t known for sure, but some researchers believe it helps preserve the body’s store of glycogen so a person can exercise longer without feeling exhausted. Caffeine may also help to speed neural transmission and suppress pain. Keep in mind that the performance boost is limited, and that caffeine can have side effects such as dizziness and nausea (especially if too much is consumed too quickly). If you do decide to consume caffeine before an athletic event, it’s best to do so about 30-45 minutes before the activity. Research studies have shown that the amount of caffeine that enhances performance ranges from 1.5 to 4 mg. per pound of body weight taken one hour before exercise. For a 150 lb. person, this comes to about 225 to 600 mg. More caffeine than recommended doesn’t add to performance.