The research revealed a similar degree of muscle-building can be achieved by using lighter weights as with bulkier ones, suggesting the secret to building muscle mass is to pump iron until you reach muscle fatigue.
“Rather than grunting and straining to lift heavy weights, you can grab something much lighter but you have to lift it until you can’t lift it anymore,” study researcher Stuart Phillips, associate professor of kinesiology at McMaster University, said in a statement. “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 findings are published online Aug. 9 in the journal Public Library of Science (PLoS) and involved 15 healthy mean with an average age of 21. The men had to lift light weights (30 percent of what the participant could lift) and heavy weights (90 percent of the subject’s best lift) with varying repetitions.