Just a half-hour of weight training can make you stronger

How little weight training can we get away with?

According to a new study of 42 healthy adult men and women, the answer seems to be about an hour a week. During the two-month study, participants gained significant muscle mass and strength from just two 30-minute sessions of uncomplicated resistance exercises each week.

The findings "highlight how powerful even a small amount of loading can be,” said Stuart Phillips, an exercise scientist at McMaster University in Canada who studies resistance training but was not involved in this research.

In each session, the volunteers completed nine common upper- and lower-body gym exercises, repeating each move eight to 10 times, until their muscles felt fatigued but not necessarily exhausted.

The routine was meant to be quick because so many people blame tight schedules for not lifting, said Brad Schoenfeld, a professor of exercise science at Lehman College in the Bronx and the study’s senior author. "We were interested in finding the minimum effective dose” of resistance training for most people, he continued.

In other words, they wanted to see, "how low can you go?” with lifting workouts, Phillips said. The results show "just how small of an investment we need to make to reap some, in my estimation, substantial rewards.”