35. HOW MANY CARBS DURING EXERCISE: 30,60,90,120 G/H? BODY SIZE MATTERS!

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In previous posts we saw that ingesting carbs (exogenous) during prolonged exercise improves durability (fatigue resilience) (Read more here and here). A hot topic is how many carbs per hour should be ingested to optimize performance in long duration races. Recommendations (e.g. 90 g/h) are generally given without considering body size. However, as the limiting factor for exogenous carbs oxidation is likely to be at gastrointestinal level. the larger organ sizes and surface areas for digestion, absorption and metabolism in larger athletes could make them able to use more exogenous carbs compared to smaller athletes.

Can larger athletes oxidise more exogenous (ingested during exercise) carbs compared to smaller ones?

A hot off the press study published by Ijaz and Colleagues (University of Bath, UK) on International Journal of Sport Nutrition and Exercise Metabolism in September 2024 tried to answer this question. (1)

This could be relevant to adjust nutritional guidelines according to body size.