The International Society of Sports Nutrition has recently published a position paper on nutrient timing. It is a 12 page review (for the full article, click here) which details the effects of various carbohydrate and protein intakes and their timing on acute and chronic exercise results.
In summary, the ISSN reports that the consumption of 8-10g of carb/kg of bodyweight within 30min of working out stimulates muscle glycogen re-synthesis. Adding protein to the mix at a rate of 3g CHO: 1g pro will increase muscle glycogen re-synthesis further. Consuming amino acids less than 3 hours after resistance training will increase protein synthesis in muscles. It is unclear if the addition of carbohydrates improves this process. During pro-longed exercise (>1hr) consuming pro with cho is better than cho alone or placebo to improve strength and body composition. Adding creatine (0.1g per kg of bodyweight) has been demonstrated to increase muscle mass.
None of this is ground breaking but the point of a position paper is to establish a common base for those who participate in an activity. In training for a triathlon, this paper puts much of the peri-nutrition research in one place and truly demonstrates that ingesting 10-15oz of 6-8% carb solution every 20 min is the best strategy. Now, what is important to understand is that this indicates what the research shows. I have had athletes who cannot tolerate drinking that much while training even accounting for a period of adaptation. So always use the research as a base. Science doesn’t mislead. That said, understand and respect individual differences in training styles. It is the adaptability of a program from the general to each individual athlete where they are and at their level that makes a coach great.