Research

Hormonal

Restoring blood glucose levels during exercise via infusion eliminates hypoglycemic symptoms but does not significantly extend performance time, indicating that cerebral hypoglycemia is not the sole limiter of endurance performance.

Drinking glucose during exercise helps prevent feeling dizzy or weak from low blood sugar, but it won't necessarily help you run longer if your muscles have already run out of glycogen. Focus on eating enough carbs before your event.

GoodRefutesHIGH confidence
Glucose infusion eliminated hypoglycemic symptoms but did not substantially increase performance time.
H. Galbo et al. · Acta Physiologica Scandinavica · 1979

Why this rating

Direct measurement of performance time and symptoms with glucose infusion.

Source

The effect of different diets and of insulin on the hormonal response to prolonged exercise

H. Galbo et al. · Acta Physiologica Scandinavica · 1979

DOI 10.1111/j.1748-1716.1979.tb06438.x

crossover · n=7Cited 253×
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DOI resolved against Crossref · corpus check 2026-06-10

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