Maybe a good strength-training program. Starting at about age 40, men lose about 1% of muscle mass a year, leading to a decrease in muscle strength and function. But engaging in a moderate and consistent strength-training program can stave off loss for decades.
Hanging onto muscle has obvious benefits. Muscle burns more energy than fat: You're less apt to pack on pounds. It also helps bones stay strong, keeps blood sugar under control and protects aging joints from injury. And, far down the road, muscle offsets frailty that can lead to serious falls.
Still, men in their 40s and 50s are probably worried less about falls and more about looking lean, mean and fit.
Some resort to testosterone replacement therapy, which studies show increases muscle size and strength, especially when combined with strength training. Prescriptions have more than doubled since 2000. They've also risen for growth hormone, but in both cases, physicians worry about side effects.
Many are more comfortable prescribing old-fashioned resistance training to combat the problem of waning muscle. Data support its effectiveness.
One study, published in the Journal of the American Geriatrics Society, reported that 14 young men and women ages 20 to 30 and 19 men and women ages 65 to 75 showed significant improvements in thigh and quadriceps muscle volume after a six-month strength-training program that incorporated exercise three days a week.
Another study followed 21 male track athletes for 20 years (starting at about age 50) and found that those who added strength training to their regimen seemed to better maintain strength as well as upper body bone density.
Muscle develops when microscopic tears occur during exercise and are then repaired. Best way to build it is via resistance exercises that are done to failure, or until no more repetitions can be done.
Employing the body (such as in push-ups) or using elastic bands or tubes provide a finite amount of resistance. Free weights, fixed weight machines and cable machines are better, says Gary Hunter, professor of human studies and nutrition sciences at the University of Alabama in Birmingham.
For men of all ages, most exercise experts recommend that drills be done with the heaviest weight that can be lifted for two to three sets of eight to 12 repetitions. Most suggest three to five days a week of strength training.
Workouts don't need to change drastically as men head into middle age, Hunter says, but some adjustments may be needed. "Older muscle takes longer to recover," he says. He recommends that the same muscle groups not be worked intensely more than twice in one week.
A standard weight-lifting program may strain older joints. Warming up and then stretching before working out may help protect them. Still, "If you keep the muscles surrounding the joints stronger, you're going to be able to protect them," Hunter says.
With age, the amount of weight a man can lift will decrease: A man bench-pressing 200 pounds at 40 might have to drop that down to 150 at 60. (Just keep the intensity of the weight fairly high, lifting between 60% and 80% of the maximum you can lift.)