< previous page page_20 next page >

Page 20
that you probably have built up a tolerance to caffeine, which reduces such side effects as nervousness, increased heart rate and increased urinationas well as any improvement in performance.
If you can wean yourself from caffeine for a few days before a race, however, caffeine may give you a lift on race day. One recent study examined the results of caffeine dosing in coffee-drinking athletes who abstained from caffeine for four days prior to a race. The research team found that blood levels of free fatty acids were greater following the withdrawal from caffeine than they were when the athletes stuck to their regular caffeine habits. These results imply that you may gain a greater benefit from caffeine if you don't regularly drink beverages that contain it or if you abstain for a few days.
The bottom line of this story is that caffeine is a plant-derived nutraceutical that can have pharmacological effects upon the body. Some of the effects are beneficial and others, in excess, can be harmful. As with all things related to nutrition, each individual should evaluate caffeine's effects upon his or her body and consume it at levels that take advantage of its beneficial effects, but minimize the adverse effects of excess intake.
As we have seen, caffeine occurs naturally or is added to many commonly consumed items, including coffee, tea, chocolate, soft drinks, and pain relievers. The International Olympic Committee has set a tolerance limit for caffeine in the urine at 12 mg/ml, which does not prevent taking caffeine with the intention of improving performance. But, taking excessive amounts of coffee or other herbs high in caffeine may cause a positive drug test.
Guarana
Guarana (Paullinia cupana) is a climbing evergreen vine native to the Amazon region. In Brazil, a carbonated soft drink made from the seeds and produced commercially is considered the national beverage. Guarana contains more caffeine than most other plants (the seeds contain as much as 7 percent caffeine). The seeds of the guarana plant are known for naturally increasing mental alertness and fighting fatigue. The seeds from this South American jungle shrub are used regularly to

 
< previous page page_20 next page >

If you like this book, buy it!