You don’t have to heft humongous weights to reap the benefits of strength training. A recent study shows that people who lift light weights with more repetition can build muscle and strength just as well as those who grunt through heavy sessions.
Researchers at Ontario’s McMaster University recruited 49 young men with two years or more of weightlifting experience and randomly divided them into two groups. One used heavy weights — 75 to 90 percent of their one-rep max — and completed eight to 12 reps until exhausted; the other lifted lighter weights — 30 to 50 percent of their max — and did 20 to 25 reps.
They all followed their regimens for 12 weeks, performing three sets four times weekly. Researchers tested their muscle strength and size and their hormone levels before and after the study.
The results, published in the Journal of Applied Physiology, showed no significant differences between the groups: Participants gained almost identical amounts of muscle strength and size.
This is good news for those who are intimidated by the prospect of pumping heavy iron, or simply confused about how best to train.
The study’s findings deliver “a message of choice,” says coauthor Stuart Phillips, PhD, professor of kinesiology. “A person in middle age who decides he or she needs to gain some muscle to slow the age-related decline in muscle mass might be intimidated by going into a gym and lifting heavy weights. Now there’s a more palatable option.”
Earlier research found similar results for older men, Phillips says. The researchers are now doing studies with women and are anticipating similar results.