Caffeine is a stimulant and is the most commonly used drug in the world.
There are a few theories surrounding the effects of Caffeine Supplementation, but one of the most common appears to be the release of adrenaline into the blood. This process increases the availability of fat as a fuel for the body’s working muscles and in the early stages of exercise the usage of muscle carbohydrate (glycogen) is reduced. The muscle glycogen is therefore reserved for use later in exercise, delaying fatigue.
Another common theory suggests caffeine supplementation has an effect on the central nervous system. This may alter an athlete’s perception of actual exercise exertion allowing them to train harder and for longer periods.
Endurance sports appear to be on the top of the list with regard to caffeine enhancement related performance. Some evidence also suggests improved performance in other events with high intensity ranging from 1 minute to events up to 60 minutes. It is unclear however that there is any enhancement in strength and power exercise and also short sprints of up to 20 seconds.
Caffeine supplement dosage is an amount of 1-3mg/kg BM or 70-200mg before and or during the exercise period. Caffeine can be taken orally, through injections and also by suppositories.
SIDE EFFECTS ASSOCIATED WITH CAFFEINE INTAKE.
Increased breathing and heart rates
Impairment or alteration of fine motor control and technique
Reduced ability to sleep
Lack of concentration
Heavy use can lead to long term side effects, for example high blood pressure, heart disease, severe insomnia and depression.
Extremely high levels (5-10grams) of caffeine intake have been associated with injury and fatality.
Endurance sports such as running, swimming, cycling and tennis appear to be the most common beneficiaries of caffeine supplementation along with some other team based sports.
The value of using caffeine supplements for the everyday exerciser is perhaps debatable considering many of the studies are performed on the elite and the studies although evidence based, can be a little conflicting and also inconclusive. It is also noted that not every person will react identically to caffeine supplements and that they may in fact have negative effects. It appears that the negatives of caffeine supplementation may out way the positives therefore could be best avoided.
References: Sports Dietitians Australia, Brian Mac Sports Coach, American College of Sports Medicine