Using a special training method with lighter weights and restricted blood flow along with heavy lifting might help trained people build more muscle by growing certain muscle fibers better, but different studies have found different results.

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.

When people do light weight training with restricted blood flow very often (at least 5 days a week), their slow-twitch muscle fibers grow bigger faster. Some less frequent training also helps, but not as much.

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.

If you're new to lifting weights, heavy lifting makes you stronger faster than light lifting with blood flow restriction, but both methods build muscle about the same.