Endurance athletes and sleepy early morning risers have used caffeine for years. Athletes and office workers alike have used it as a way to stay alert and improve endurance. For more than 30 years it has been studied in relation to its performance enhancing ability and has only recently been removed from the banned list of the International Association of Athletics Federations (IAAF) earlier this year.

It is one of the best-researched nutritional supplements, and the overwhelming scientific evidence suggests that, in moderation, it has very few to no adverse health effects. When abused, it can cause annoying little problems such as increased urination, stomach upset, headaches and trouble sleeping. Athletes who normally avoid caffeine may experience adverse effects if they start using it as an ergogenic aid without first determining how it will effect them. Always test any supplement before using in a race or hard training session.

Many athletes have experienced success when using caffeine as a performance enhancing supplement with very few problems. Many studies have looked at the effects of caffeine on exercise and found that caffeine can delay fatigue and help increase energy levels, increase alertness and even decrease muscle pain. All these positive effects lead to workouts that are longer, more productive and often more enjoyable to the athlete. One technical reason for this is due to the effect caffeine has on the increased stimulation of the central nervous system.

The recommended dose to help enhance endurance workouts is about 6 mg per kg of body weight. The scientific literature also suggests that the risk of negative side effects is increased if caffeine is taken in doses higher than 9mg per kg of body mass. Experiment with different dosages in your training to see what works best for you.

Caffeine is found naturally in coffee beans, tea leaves, chocolate, cocoa beans and cola nuts, and is often added to carbonated drinks. The average cup of coffee has about 60 mg to 120 mg, so it does not take a whole pot of coffee to do the job. Caffeine pills are also an option to really dial in correct dosages.

Caffeine can be absorbed by the body very fast, with peak concentration reached in around one hour. The half-life of caffeine, the time required for the body to eliminate one-half of the total amount of caffeine, varies widely among individuals. Depending on factors such as age, liver function, pregnancy, and some medications, caffeine's half-life is approximately five hours in healthy athletic adults. Women who take oral contraceptives can increase this time to five to ten hours, and in pregnant women, the half-life is roughly nine to eleven hours. Therefore, in order to find your individual optimal time to take caffeine may take some experimenting.

Athletes engaged in heavy endurance training often seek additional nutritional strategies to help maximize performance, however as with any intervention or use of supplementation, individual responses will vary. Athletes should monitor their caffeine dosage strategy before putting it to the test in a competition. Caffeine can benefit you in a race but does not replace a sound everyday diet.

Jarrett Pflieger is a USA Triathlon Level 1 certified coach and facility director of Triathica, a triathlon training center in Orange County, CA.