Last time you waved your arm, did you notice a bit of flesh flapping? Then you’re already familiar with how growing older can affect your muscles. “If you’re sedentary, you can lose 8 percent of your muscle mass between ages 40 and 50,” says Vonda Wright, MD, an orthopedic surgeon in Pittsburgh and the author of Fitness After 40: How to Stay Strong at Any Age. Losing muscle mass doesn’t just leave your arm looking flabby; it costs you physical strength. Aging can also contribute to a less visible but quite serious concern—muscle “imbalances” that set you up for pain and injuries. Here’s what happens: Over the course of years, your everyday habits (carrying an overstuffed purse on your left shoulder, sitting at your computer for hours at a time, wearing high heels) tighten some muscles and weaken others. And the physical activity that will help prevent and reverse age-related muscle loss may not solve the imbalance issue. “Activities such as walking, biking, swimming, running, doing yoga or lifting weights regularly can overtrain some muscles and ignore others,” Wright says.
The problem is that our joints are held in place by opposing muscle groups, such as the chest and back muscles, quads and hamstrings, hip flexors and the gluteus maximus (in the buttocks). To prevent pulls, strains and chronic aches, you need to maintain these muscle groups in a healthy, yin-yang kind of equilibrium. But what you do with your body all day can easily throw everything out of whack. Hunching over your computer, for instance, can tighten your chest muscles and weaken those in your upper back, an imbalance that often leads to neck and back pain—if not now, then probably in your future.
It’s relatively easy to develop the correct muscle balance. Use the following tests to identify your weak or tight spots. Then strengthen or lengthen those trouble areas by doing these exercises three or four times a week.
Sore points: groin, butt or back
Possible pain source Tight hip flexors, the muscles at the front of your hips that allow you to lift your knees, bend at the waist, climb stairs and run. When too taut, hip flexors cause your pelvis to tilt forward, which stresses the muscles of the lower back and spine, making you more susceptible to hamstring strains and lower-back pain.
Test yourself Lie on back and bring right knee to chest. Hold on to knee with right hand, keeping left leg as flat on the floor as you can. If left leg doesn’t relax against the floor, hip flexors on that side are tight. Switch sides.
Why the imbalance Too much sitting! “Working at a desk all day causes your hip flexors to tighten and your butt muscles to weaken,” says Scott Bautch, a chiropractic sports physician in Wausau, Wisconsin. Wearing heels consistently can contribute to the problem, too, he notes.
The fix “During the day, get up and move around at least once every hour to loosen your hip flexors,” says Bautch. And do this exercise: Standing with hands on hips, step forward with left foot into a deep lunge, making sure left knee doesn’t extend forward beyond left toes. Holding that position with legs, shift hips forward so you can feel the tension in front of right hip. Hold for 30 seconds, then repeat with other leg. Do three more times.
Sore points: shoulders, neck or upper back
Possible pain source Tight rotator muscles in your shoulders.
Test yourself Reach behind head with right hand and try to touch left shoulder blade. Then try to do the same move with left hand on other side. If you can’t meet your target, you have tight rotator muscles; they’re often less flexible on one side than the other.
Why the imbalance Carry-ing a heavy purse on one side, playing tennis or doing overhead strength-training moves without stretch-ing afterward.