Science-backed answers from the research and the community.
Editorial articles
Why 20-Mile Walks Were Reported During Extended Fasts (And What That Tells Us)
Upton Sinclair documented fasters walking 20+ miles during extended fasts in 1911. Here's why fasted walking works and what modern exercise science confirms.
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Fasting and Athletic Performance: A Historical and Modern Perspective
Upton Sinclair's 1911 book The Fasting Cure documented fasters walking 20 miles a day. Here's what his cases and modern exercise science say about fasting and performance.
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Can You Exercise During a Fast? What Historical Cases and Modern Research Say
Can you exercise during a fast? Upton Sinclair's 1911 case studies and modern science both weigh in on movement, walking, and workouts while fasting.
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Why Heavy Physical Labor and Fasting Don't Mix
Upton Sinclair's 1911 book The Fasting Cure warned against heavy manual labor while fasting. Here's his reasoning and what modern science adds to it.
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Walking While Fasting: Why Low-Intensity Movement Helps
Discover why Upton Sinclair's 1911 fasting cases favored walking over rest, and what modern science says about light movement during a fast.
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When Is the Best Time to Exercise During Intermittent Fasting?
Find the best time to exercise during intermittent fasting for fat loss, muscle gain, and energy. Practical guide based on how ketones, insulin, and timing interact.
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Can you do HIIT while intermittent fasting?
Yes, HIIT during intermittent fasting works excellently. Here's how to do it safely and maximize performance while fasted.
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Can you build muscle while intermittent fasting?
Yes, you can build muscle while intermittent fasting. Here's how to combine fasting with strength training using the science-backed approach from Intermittent Fasting in Practice.
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How Does Intermittent Fasting Affect Athletic Performance?
Intermittent fasting can sharpen focus, stabilize energy, and boost HGH — but it changes how your body fuels exercise.
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Can You Do Strength Training While Fasting?
Yes — strength training while fasting is not only safe but can be effective for fat loss and muscle retention. Here's what you need to know to do it right.
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What to Eat After Working Out During Intermittent Fasting
Post-workout nutrition during intermittent fasting: the best foods to eat, when to eat them, and how to time your first meal for muscle recovery and fat burning.
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Does Fasted Cardio Burn More Fat?
Fasted cardio burns a higher proportion of fat during exercise, but total fat loss depends on your fasting window and diet quality — here's what the evidence shows.
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Should You Work Out in a Fasted State?
Wondering if fasted workouts actually work? Here's what happens when you exercise while intermittent fasting — and how to do it right.
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Can You Exercise While Intermittent Fasting?
Yes — and for most people, fasted exercise works better than they expect. Here's what the book and experience teach.
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