{"id":204736,"date":"2026-02-17T12:39:25","date_gmt":"2026-02-17T12:39:25","guid":{"rendered":"https:\/\/www.welovecycling.com\/wide\/?p=204736"},"modified":"2026-02-17T12:39:25","modified_gmt":"2026-02-17T12:39:25","slug":"cyclist-immunity-does-fuelling-change-your-infection-risk","status":"publish","type":"post","link":"https:\/\/www.welovecycling.com\/wide\/2026\/02\/17\/cyclist-immunity-does-fuelling-change-your-infection-risk\/","title":{"rendered":"Cyclist Immunity: Does Fuelling Change Your Infection Risk?"},"content":{"rendered":"

Fuelling is often overlooked as a factor that can make the difference between staying healthy and getting sick. Does what you eat and drink actually change your risk of infection? The short answer is yes, and the way you fuel during winter training, especially, could be the key to avoiding those frustrating setbacks.<\/strong><\/p>\n

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The carb-immune connection<\/strong><\/h2>\n

When you ride hard, especially in cold conditions, your body burns through glycogen rapidly. If you don\u2019t replenish those carbs, your blood sugar drops, and your body responds by releasing stress hormones like cortisol and adrenaline. While these hormones help mobilise energy, they also suppress immune function, particularly the activity of natural killer cells and white blood cells that fight off viruses.<\/p>\n

Low blood sugar = higher stress = weaker defences<\/p>\n

Studies found that cyclists who consumed at least 30 g of carbs per hour during intense exercise had significantly lower cortisol responses compared to those who trained fasted or with only water. Lower cortisol means less immune suppression and a lower risk of picking up that cold going around your training group.<\/p>\n

What this means for you:<\/strong><\/p>\n

Fuel early and often:<\/strong> Start consuming carbs within 30\u201345 minutes of beginning a ride that\u2019s longer than 90 minutes.<\/p>\n

Prioritise easily digestible carbs:<\/strong> Glucose, maltodextrin or simple sugars (like those in sports drinks or gels) are absorbed quickly and help maintain blood-sugar levels.<\/a><\/p>\n

Don\u2019t skip post-ride carbs:<\/strong> Consuming carbs within 30 minutes of finishing a hard session helps replenish glycogen and further reduces stress hormone spikes.<\/p>\n

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\"cyclist-immunity-the-indoor-air-and-sunshine-problem\"\/<\/a><\/div>
\n Health & Training<\/a>\n <\/div>\n
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Cyclist Immunity: The Indoor Air and Sunshine Problem<\/span><\/h3>\n <\/a>\n <\/div>\n <\/article>\n<\/div>\n

Long-term under-fuelling matters too<\/strong><\/h2>\n

Many cyclists, especially those trying to \u201clean out\u201d for spring, cut carbs or calorie intake in general during winter training. A calorie deficit that is too large or lasts for too long can pose a serious risk to the immune system. Research on Relative Energy Deficiency in Sport (RED-S) shows that athletes who consistently underfuel experience:<\/p>\n