Fasting on this site mostly means a consistent eating window, not a 72-hour identity. Satchin Panda put a clock on it: 8–12 hours of food, the rest empty, same-ish every day. Berg put it on YouTube with keto. The Complete Guide to Fasting is the longer protocol book. Stacy Sims will tell you a luteal week plus a hard session is a bad time to play hunger games.
A window, not a religion
Pick 10 hours if 8 feels like a dare. Finish food earlier than your current 10 p.m. snack. Keep weekends from exploding the clock. You can still hit protein. Under-fueling plus HIIT is how people get cold, injured, and smug.
Longer fasts (24h+) are a separate tool. Interesting for some metabolic experiments. Easy to screw up if you take meds, have a history of disordered eating, or train hard. This page lives under metabolism and talks to longevity and gut. It does not cancel lifting.
FAQ
Is 16:8 magic?
It is a schedule that stops evening grazing. The magic is often fewer calories and better sleep, not a secret enzyme.
Can I fast and still gain muscle?
If protein and total food still land. A tiny window that starves the session will not grow anything.
Who should not fast?
Pregnancy, history of eating disorders, insulin-dependent diabetes without a clinician, anyone who faints when they skip breakfast. Kids. That list is not complete.
Not a medical fast. Medications and blood sugar disorders need a doctor in the loop.
