Short answer: Yes. Intermittent fasting is just a schedule and does not block or boost muscle growth by itself. Total food for the day is what counts, so pick the eating window that makes it easiest to hit your protein and calorie numbers.
Intermittent fasting (IF) means squeezing all your eating into a shorter window, like 8 hours a day. People worry this hurts muscle growth. Studies say: mostly no.
What the Studies Found
In Moro et al. (2016), trained men ate everything in an 8-hour window for 8 weeks. They kept all their muscle and lost more fat than the group eating on a normal schedule. Strength stayed the same in both groups.
Another study found similar results — fasting didn’t hurt strength gains. Muscle gains were a tiny bit lower in the fasting group, but not by much, and not enough to call it a real difference.
The Part That Actually Matters
What builds muscle is your total protein and calories for the day — not when you eat them. The reason fasting sometimes looks slightly worse isn’t the fasting itself. It’s that cramming all your food into 8 hours makes it harder to eat enough, especially if you’re trying to eat a lot to gain muscle.
If you eat 3,000 calories and 180g of protein in an 8-hour window, you’ll build muscle just as well as someone eating the same amount spread across 12 hours. Fasting doesn’t block muscle growth on its own — it just makes hitting your numbers a bit harder for some people.
Who It Works Well For
- People who like fewer, bigger meals
- People trying to lose fat who find it easier to control hunger this way
- People who train fasted and feel fine doing it (most people do fine, though very hard or long sessions might suffer a little)
Who Should Skip It
Anyone trying to eat a lot of food to build muscle fast. Cramming 3,500+ calories into a short window gets uncomfortable fast.
Bottom Line
IF is just a schedule, not something that blocks or boosts muscle growth by itself. Total food for the day is what counts. Pick whatever schedule makes it easiest for you to hit your numbers.
Sources
- Moro et al. (2016) — Effects of eight weeks of time-restricted feeding (16/8) on basal metabolism, maximal strength, body composition, inflammation, and cardiovascular risk factors in resistance-trained males. Journal of Translational Medicine, 14, 290.
- Tinsley et al. (2017) — Time-restricted feeding in young men performing resistance training: A randomized controlled trial. European Journal of Sport Science, 17(2), 200–207.