Why eating the right carbs before a long run helps you keep going
Effect of quantity and quality of pre-exercise carbohydrate meals on central fatigue.
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
Surprising Findings
Higher serotonin levels were linked to greater central fatigue, not less.
Serotonin is commonly thought of as a 'feel-good' neurotransmitter, but here it’s associated with reduced muscle activation and increased fatigue during exercise.
Practical Takeaways
Eat 1.5g of carbs per kg of body weight (e.g., 105g for a 70kg person) with a high glycemic index (like white bread, rice, or sports drinks) 1–2 hours before a 90+ minute run.
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
Surprising Findings
Higher serotonin levels were linked to greater central fatigue, not less.
Serotonin is commonly thought of as a 'feel-good' neurotransmitter, but here it’s associated with reduced muscle activation and increased fatigue during exercise.
Practical Takeaways
Eat 1.5g of carbs per kg of body weight (e.g., 105g for a 70kg person) with a high glycemic index (like white bread, rice, or sports drinks) 1–2 hours before a 90+ minute run.
Publication
Journal
Journal of applied physiology
Year
2018
Authors
T. Khong, V. Selvanayagam, S. Hamzah, A. Yusof
Related Content
Claims (4)
Eating a meal with 1.5 grams of carbohydrate per kilogram of body weight before running for 90 minutes helps maintain muscle strength and nervous system drive during the run better than eating a meal with 0.8 grams per kilogram, and leads to higher use of carbohydrates for energy and a stronger insulin response.
Eating high glycemic index carbohydrates before running may help maintain muscle strength, neural activation, and tryptophan levels during prolonged exercise, and lead to higher rates of carbohydrate burning and insulin release compared to low glycemic index carbohydrates.
When athletes consume carbohydrates before running for a long time, higher rates of carbohydrate use and insulin release are linked to less decline in the brain's ability to fully activate muscles during the run.
Eating a meal high in carbohydrates before doing cardio exercise increases how effectively insulin promotes the building of muscle and fat tissue in the body.