Caffeine & Exercise part 3: Usage in training

Effects during exercise

Found in almost every pre-workout on the market, caffeine is there for a reason; it packs a powerful boost for strength and aerobic exercise. Its not just mere hearsay either, there appears to be a reliable and significant increase in power output in both trained and sedentary persons with doses of caffeine exceeding 5mg/kg, assuming the subject is not caffeine tolerant. Tolerance, or lower doses of caffeine, are not as effective, with a caffeine dosage of 400-600mg one of the most reliable and potent ways to temporarily increase strength through supplementation.

There is a significant body of evidence that caffeine has a consistent, but a minor improvement on aerobic exercise capacity, likely due to the increased free fatty acids and serum adrenaline. A general guide is to take ~3-5mg of caffeine per kg of body weight and hour prior to the race and every subsequent 1.5 hours during a prolonged aerobic event. 

Take home message

• For increases in power output take 400-600mg of caffeine an hour before working out. 

• For endurance exercise take 5mg/kg/kg body weight an hour prior to exercise

• To avoid being dehydrated from caffeine use, always have it with liquid and avoid high doses. 

•  If you want to maximise the benefits of caffeine, taking breaks from using it every couple of months and  only using it on workouts where you really need the boost will make sure it remains as effective as possible. 

• When working out frequently and wanting to maximize muscle glycogen store replenishment, ~150mg with carbohydrates maximised replenishment 

• Caffeine has a 6 hour half life, so ideally have it before 4pm to avoid causing sleep disturbances.