14/09/2026
Race to the Sea: 100 miles, 7 hours 45 minutes in the saddle 🚴
For this event, I used a continuous glucose monitor (CGM) to observe my glucose response during prolonged endurance exercise. My trace remained largely within the target range, with expected rises after carbohydrate intake and dips as working muscles used glucose for energy.
Why does this matter?
During long-duration exercise, muscles draw on both stored glycogen and blood glucose. Consistent carbohydrate intake can help maintain blood glucose availability, support exercise intensity and delay fatigue. Sports-nutrition guidance commonly suggests around 30–60 g carbohydrate per hour for longer sessions, with some athletes tolerating up to 90 g/hour when they have practised their strategy and use multiple carbohydrate sources. The right target is always individual: race duration, intensity, heat, gut tolerance and personal preference all matter. ISSN position stand
A CGM can be an interesting educational tool, but it does not replace listening to your body or an individual nutrition plan. The aim is not a perfectly flat line; it is a well-practised fuelling and hydration strategy that supports performance, recovery and gastrointestinal comfort.
My biggest takeaway: practise your race nutrition in training. Your gut is trainable, and a plan you can consistently tolerate is more useful than a “perfect” plan on paper.
My fuel included:
5 GU gels + 1 GU Roctane gel
Amacx Energy drink
Potatoes along the way
