extreme caffeine We all know that caffeine can give you a quick boost, but it also has a mild effect on increasing fat burning both at rest and during exercise. It may also increase endurance and even some types of strength training. A series of studies shows caffeine may also consistently decrease the sensation of pain during exercise. The research group has published 3 studies each examining the effects different doses of caffeine intake on leg pain in men and women. In one experiment they showed that both regular caffeine consumers and those who did not consume caffeine experienced less leg pain during 30 min of moderate intensity cycling exercise after caffeine intake (equivalent to about 2-3 strong cups of coffee) compared to placebo. In another study, they had young women exercise at a slightly higher intensity for 30 min following intake of caffeine or placebo. Caffeine was shown to dramatically decrease perceived rating of leg muscle pain. In a third experiment, two doses of caffeine were tested in women who were low caffeine consumers. Both the low and high dose caffeine again significantly reduced leg muscle pain scores during 30 min of exercise. These studies show caffeine intake at moderate levels has a consistent effect on reducing the sensation of pain during moderate intensity exercise. The effect is evident in men and women and does not depend on regular caffeine intake. It appears that caffeine can act on the brain to block some of the uncomfortable feelings associated with physical exertion.

Gliottoni RC, Meyers JR, Arngrímsson SA, Broglio SP, Motl RW. Effect of Caffeine on Quadriceps Muscle Pain During Acute Cycling Exercise in Low Versus High Caffeine Consumers. Int J Sport Nutr Exerc Metab. 19(2), April 2009.
Gliottoni RC, Motl RW. Effect of caffeine on leg-muscle pain during intense cycling exercise: possible role of anxiety sensitivity. Int J Sport Nutr Exerc Metab. 2008 Apr;18(2):103-15.
Motl RW, O'connor PJ, Tubandt L, Puetz T, Ely MR. Effect of caffeine on leg muscle pain during cycling exercise among females. Med Sci Sports Exerc. 2006 Mar;38(3):598-604.