Unbalanced muscles can cause pain

NEW YORK - When you head out for your daily run, with each stride, you are strengthening your quadriceps, hamstrings and upper calf muscles. The muscles on the sides of your hips, however, are not growing much.

If you regularly do one sport - like running, biking or tennis - and rarely do anything else, you run the risk of having muscle imbalance.

Imbalances happen when one muscle is significantly stronger than another. The two muscles can be on opposite sides of a joint or bone, or across the body.

For example, if a weightlifter overtrains his or her biceps and ignores the triceps, or an office worker spends 10 hours a day peering at the computer screen, leading to weak shoulder muscles, imbalances can emerge. This can lead to pain, poor posture and injury.

Dr. Ann Crowe, a physical therapist in Clayton, Missouri, who works primarily with runners and cyclists, said most of her clients' foot, knee, hip and back pain can be traced to these imbalances.

Runners and cyclists typically focus on the cardiovascular benefits of their sports, but neglect strength training, she said. As a result, they often have weak glutes and strong quads.

Studies suggest that muscle imbalance can especially contribute to shoulder, lower back, elbow and wrist injuries in athletes who play sports with overhead movements, such as water polo, tennis and basketball.

Muscular imbalance is also caused by sitting in a chair for hours on end. When experts studied office workers, they found muscle imbalance tied to neck pain in as many as 70 per cent of subjects.