"As far as calorie replenishment is concerned, the body has a limit to what it can accept from carbohydrate donation for return to the energy cycle. Researchers such as Coleman, Noakes and others (in carbohydrate oxidative research) agree that up to 1.0-1.1 grams of carbohydrate per minute can be utilized from exogenous (outside) carbohydrate donation. A 1.0 g/carb per minute donation is 240 carbohydrate calories per hour. A 1.1 g/carb per minute donation is 264 carbohydrate calories per hour. Taking into account that some of those calories- approzimately 6-23%- are burned/lost during the digestive process, this suggests that for the average athlete the minimum intake is 254.4 calories to obtain 240 calories per hour (1.0 per minute with 6% lost in route) while the absolute upper maximum is 324.72 carbohydrate calories required in order to regenerate 264 carbohydrate calories (1.1 per minute with 23% lost in route).

We take a slightly more conservative side and suggest a slightly lower overall dose after finding that these higher amounts only induced gastric stress disorders and reduced performance in many athletes. This is why our common recommendation is approximately 60-70 grams of carbohydrates (240-280 calories). That will, in most situations, and for most athletes, provide enough carbohydrates for energy production (the limit of what the body can metabolize) while taking into account a percentage of those calories being lost/burned during the digestive/metabolic processes."

Quoted from Hammer Gel's website.