According to the NY Times, you don’t have to use extremely heavy weights at the gym to get good results. You can use lighter, more comfortable weights. Just up the number of repetitions, lift until your muscles are tired, and you’ll get the same results: increased muscle size, increased strength, and a surge in human growth hormone.
The opening paragraph says it all:
Upending conventions about how best to strength train, a new study finds that people who lift relatively light weights can build just as much strength and muscle size as those who grunt through sessions using much heftier weights — if they plan their workouts correctly.
The article reports on a study of young men who were divided into two random groups. One group lifted extremely heavy (for them) weights. The other group lifted lighter weights but did more repetitions. Both groups lifted until they reached muscle fatigue.
After twelve weeks of training, the volunteers were assessed again. And…?
The results were unequivocal. There were no significant differences between the two groups. All of the men had gained muscle strength and size, and these gains were almost identical, whether they had lifted heavy or light weights.
Interestingly, the scientists found no connection between changes in the men’s hormone levels and their gains in strength and muscle size. All of the men had more testosterone and human growth hormone flowing through their bodies after the workouts. But the degree of those changes in hormone levels did not correlate with their gains in strength.
Instead, the key to getting stronger for these men, Dr. Phillips and his colleagues decided, was to grow tired. The volunteers in both groups had to attain almost total muscular fatigue in order to increase their muscles’ size and strength.
The conclusion?
For now, someone hoping to strengthen his or her muscles should choose a weight that feels tolerable and then lift it repeatedly until the effort of the final lift is at least an eight on a scale of one to 10, Dr. Phillips says. “There should be some discomfort,” he says, “but the dividends on the back side” in terms of stronger, healthier muscles “are enormous.”
