Depending on preparation, one cup of brewed coffee contains etween 60 and 150 mg of caffeine, instant coffee about 100mg, brewed tea between 20 and 50mg and caffeinated soft drinks. I January 2004 the IOC removed caffeine from its list of banned substances.
Drinking 2.5 cups of percolated coffee (300mf of caffeine) up to 1 hour before exercise extends endurance ; it also improves short duration, high intensity exercise. This is roughly a 5mg/kg of body weight. The ergogenic effects of caffeine are not dose relayed with no additional benefits from caffeine doses above 5m/kg of body weight. The effect also last 5 hours so there is no need to ingest additional dose.
Its precise action is elusive. In the past it has always been attributed to its use of fat in the initial exercise period thus sparing the powerful carbohydrate fuel which can be used later. However, other erogogenic effects includes its enhancement of motoneuronal activity.
There are health warnings with caffeine however - irritability, headaches, insomnia, agitation dehydration etc. With caffeine, ingesting small amounts produces desirable effects, large quantities can create havoc.
No comments:
Post a Comment