Tea, coffee, cola soft drinks and many commercial energy drinks are commonplace in the diet of many Australians. Caffeine is a compound that acts on the central nervous system, increasing the heart rate and breathing rate and relaxing smooth muscle. Primarily, people consume caffeinated beverages to kick-start the day, improve alertness and concentration and buffer the perception of the onset of fatigue. Caffeine has been recognized as an ergogenic aid that can have a positive effect on the performance of exercise. Up until 2004, caffeine was on the International Olympic Committee’s banned substance list for in-competition use when at a level equivalent to more than 4 cups of coffee in the system. The detection of caffeine when used for performance enhancement is through the urine sample of an athlete. Currently, caffeine is on the ‘monitored’ list for in-competition use, and is no longer banned by the IOC.
But why all the fuss? In addition to increasing alertness and prolonging the onset of fatigue, caffeine spares glycogen as a fuel source and allows free fatty acid release into the blood stream. It is these energy dense fatty acids that can then be utilized as a fuel source in aerobic exercise. Although using up fats as energy can seem a very attractive prospect, the detriment of caffeine use is its diuretic effect, encouraging water loss from the kidneys. The loss of fluid can have more disadvantages than the possibility of increasing performance through muscle glycogen sparing.
So how much is enough? Every person has a different level of sensitivity to caffeine but most can handle around 4 cups of coffee across the day with no significant health problems. Caffeine is not held in the body but cleared in the urine 3-7hours after consumption, supporting claims that caffeine can have an effect on sleep patterns but only when consumed within this given time frame before bed. Ultimately, every individual experiences different symptoms when consuming caffeine. One person may tolerate only one cup of coffee a day whereas the next may be able to consume many cans of cola before the central nervous system reacts. It is important to understand your bodies own sensitivity and the possible side-effects associated with any food or ergogenic aid, even when disguised as a caramel latte!
