Why fasting before a walk burns more fat

Original Title

Effects of aerobic exercise performed in fasted v. fed state on fat and carbohydrate metabolism in adults: a systematic review and meta-analysis

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

Summary

When you exercise without eating first, your body burns more fat during the workout — even though the fat floating in your blood doesn’t change.

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Surprising Findings

NEFA (fat in blood) didn’t increase during fasted exercise—even though more fat was being burned.

Common belief: burning more fat = more fat released into blood. But this study shows fat oxidation increased without a rise in circulating fat, pointing to internal muscle mechanisms.

Practical Takeaways

Do 30–60 minutes of moderate cardio (walking, cycling) before breakfast if you want to maximize fat burning during the session.

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