Squeezing blood flow while doing light weight training might still help your muscles grow and get stronger — you don’t have to lift heavy to see results.

You can make your muscles grow bigger by lifting very light weights if you restrict blood flow to your arm or leg — it tricks your body into thinking you’re lifting heavy.

If young women do light weightlifting while wearing special bands that squeeze their arms or legs, they can get stronger and their muscles can grow bigger in just four weeks—without lifting heavy weights at all.

For people who exercise casually but aren’t trained, doing light weightlifting with blood flow restriction helps grow fast-twitch muscle fibers almost as much as lifting heavy weights — and after 6 weeks, the difference between the two isn’t big enough to matter.

If you wear tight bands around your arms or legs only when you're resting between weightlifting sets, your muscles will produce more lactic acid afterward than if you wear them while lifting or not at all—but that extra burn doesn’t make your muscles grow bigger or stronger.

If you do light weightlifting with a band around your arm to restrict blood flow, whether you're pushing or lowering the weight doesn’t seem to matter—both ways make your muscles stronger and bigger about the same amount in four weeks.