This research works for me!
Writing in the April issue of the International Journal of Sport Nutrition and Exercise Metabolism, the researchers said that regardless of exercise intensity level, subjects who consumed caffeine saw a reduction in pain during exercise, whereas the control group did not. Althought the researchers were quick to point out that all pain is subjective and based on personal perception, they did conclude that caffeine may have a "moderate hypoalgesic effect" on cyclists who exercise at high intensity for 30 minutes.