Caffeine has been shown to improve performance, speed, power, and endurance capacity when consumed before a run [1
]. Consuming 3-6 mg of caffeine/kg of body weight 15 - 60 minutes before exercise seems to benefit most runners. While individual responses to caffeine vary, research suggests total caffeine intake shouldn’t exceed 400mg/day [3
]. To put it in perspective, 1 cup of coffee (8 oz.) provides about 100 mg of caffeine.