If you feel shy about starting a strength-training program, it may help to sweep a few myths from your mind.

Myth: Strength training is only for the young. Older people might injure themselves.

Fact: Older people need it even more than the young, in order to counteract the decline in muscle strength that usually comes with aging, due to decreasing activity. If you’re over 50, strength training can be your new best friend.

Myth: It’s for body builders only.

Fact: A moderate program that confers health benefits isn’t going to make your biceps bulge. Strength training not only builds muscle, but also helps reduce body fat and increase bone.

Myth: It’s for men only.

Fact: Women, perhaps even more than men, can benefit from strength training. Women are more likely to suffer from osteoporosis, which strength training can help prevent.

Myth: Women need a different program from men. For example, they should not lift barbells.

Fact: Women and men can follow the same program of exercises designed for their body size and level of strength, not for their gender. Women can lift barbells. What you do depends on your level of ability. There’s something for everybody.

Myth: It’s very time-consuming—hours every week.

Fact: Strength training can be one of the fastest workouts—less time-consuming than aerobic exercise like running or walking. Three 20-minute sessions a week (preferably not on consecutive days) will do the job.

Myth: If you lift weights, that’s all the exercise you need.

Fact: You still need to do aerobic exercise. One type is not a substitute for the other. Doing both pays real dividends.