We know that maintaining muscle mass is important to good health, especially as we age. But is it really obligatory to lift heavy weights to keep muscles in shape? Not necessarily, says a new study conducted at McMaster University, in Ontario, Canada, which shows that effective muscle building also can be achieved by using lighter weights and pumping until the muscles in the targeted area are fatigued.

“Rather than grunting and straining to lift heavy weights, you can grab something much lighter, but you have to lift until you can’t lift it anymore,” says Stuart Phillips, associate professor of kinesiology at the university. “We’re convinced that growing muscle means stimulating your muscle to make new muscle proteins, a process in the body that over time, accumulates into bigger muscles.” The new paradigm contradicts current gym dogma and is welcome news for those who cannot lift heavy weights or simply don’t want to.