Why your muscles run out of fuel during weightlifting

Original Title

Acute effects of resistance exercise on skeletal muscle glycogen depletion: A systematic review and meta‐analysis

Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms

Summary

When you lift weights, your muscles use up stored sugar (glycogen) — but how much depends on how you lift.

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Surprising Findings

Higher lifting intensity reduces glycogen depletion

Everyone assumes lifting heavier = more energy used. But this study shows heavier weights mean fewer reps and less total volume, so less sugar burned.

Practical Takeaways

If you do 8+ sets per muscle group or mix heavy/light sets, eat 30–50g of fast carbs within 30 minutes post-workout.

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