For people new to strength training, lifting light weights with restricted blood flow works just as well as lifting heavy weights for building muscle size over 6 weeks.

When adults do light weight training with restricted blood flow, their slow-twitch muscles grow as much or more than their fast-twitch muscles, which is different from heavy weight training where fast-twitch muscles usually grow more.

When people do light weightlifting with restricted blood flow, their slow-twitch muscles can grow as much or more than their fast-twitch muscles, which is different from heavy lifting where fast-twitch muscles usually grow more.

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.

Doing light weightlifting with a band that restricts blood flow for six weeks can make both slow and fast muscle fibers in older people grow bigger by about 20%, even without heavy lifting.

At first, your muscles might actually get a little smaller from this kind of training, but after doing it again later, they grow bigger than before — the growth just takes time to show up.