7 Biggest Nutrition Mistakes Runners Make (And How to Fix Them)

Is fasted running sabotaging your performance? Are you accidentally under-eating on your hardest training days? This week, we break down the seven most common nutrition mistakes runners make, from calorie restriction at the wrong time to blindly copying elite protocols, and explain why the science says you probably need to eat more, not less.We cover why your gut issues might actually be a training problem, not a food problem. We talk about why "clean eating" is often just restriction in disguise. And we explain why doing what Kipchoge does probably isn't what you should be doing.Plus, we answer listener questions on accountability and whether high-carb fueling causes diabetes (spoiler: it doesn't). And Coach James Nance joins to talk about coaching multi-sport athletes, helping runners recover from overtraining, and his TrainingPeaks hot take that might surprise you.In this episode:Why restricting calories on training days backfiresThe truth about fasted running and morning workoutsHow to actually fix gut issues during exerciseWhy "clean eating" can become problematicWhat 90-120g of carbs per hour actually means for recreational runnersHow to evaluate nutrition advice and follow the moneyStudies and resources mentioned are linked below.Get involved: Join our Foothills coaching community—one-on-one coach access, twice-monthly roundtables, and a supportive crew of runners. $10/month with code FOOTHILLS10 at microcosm-coaching.com.Questions? [email protected]:Burke, L. M., Ross, M. L., Garvican-Lewis, L. A., Welvaert, M., Heikura, I. A., Forbes, S. G., Mirtschin, J. G., Cato, L. E., Strobel, N., Sharma, A. P., & Hawley, J. A. (2017). Low carbohydrate, high fat diet impairs exercise economy and negates the performance benefit from intensified training in elite race walkers. Journal of Physiology, 595(9), 2785–2807.Costa, R. J. S., Hoffman, M. D., & Stellingwerff, T. (2019). Considerations for ultra-endurance activities: Part 1 – Nutrition. Research in Sports Medicine, 27(2), 166–181.Cox, G. R., Clark, S. A., Cox, A. J., Halson, S. L., Hargreaves, M., Hawley, J. A., Jeacocke, N., Snow, R. J., Yeo, W. K., & Burke, L. M. (2010). Daily training with high carbohydrate availability increases exogenous carbohydrate oxidation during endurance cycling. Journal of Applied Physiology, 109(1), 126–134.Loucks, A. B., & Thuma, J. R. (2003). Luteinizing hormone pulsatility is disrupted at a threshold of energy availability in regularly menstruating women. Journal of Clinical Endocrinology & Metabolism, 88(1), 297–311.Melin, A. K., Heikura, I. A., Tenforde, A., & Mountjoy, M. (2019). Energy availability in athletics: Health, performance, and physique. International Journal of Sport Nutrition and Exercise Metabolism, 29(2), 152–164.Mountjoy, M., Ackerman, K. E., Bailey, D. M., Burke, L. M., Constantini, N., Hackney, A. C., Heikura, I. A., Melin, A., Pensgaard, A. M., Stellingwerff, T., Sundgot-Borgen, J. K., Torstveit, M. K., Jacobsen, A. U., Verhagen, E., Budgett, R., Engebretsen, L., & Erdener, U. (2023). 2023 International Olympic Committee's (IOC) consensus statement on Relative Energy Deficiency in Sport (REDs). British Journal of Sports Medicine, 57(17), 1073–1098.