Suspected dual quad pull.

? In each of the three marathons I have run, I've experienced pain in each quadriceps, beginning around mile 18. It gets so I need to take walk breaks periodically until the end of the race. Are these muscles pulling? And how can I prevent this from occurring in the future?

Allen Burns, Jamestown, NY

You may not have pulled your quads so much as taxed them, as many marathoners do, by allowing your form to deteriorate in the late miles of the race. How do photos of you look at the finish? Is your body weight collapsing to the inside of your knee and foot? This posture places less of the load on your gluteals and much more on your quads.

To avoid this in the future, you may develop hip extensor and abductor strength with various drills like skipping and bounding. When you run, focus on carrying yourself upright over your feet as you move to toe off. Avoid slouching and running "behind your feet." Have a friend observe your form or try videotaping it on a track.

John Cianca, MD, Houston, TX

Without knowing your age or weight, it's difficult to assess what's happening here. You seem to be describing muscular pain, and the fact that it's in both thighs reduces the chance of stress fracture. If the pain is accompanied by tightness or weakness in your quads, they may well be pulled. However, tight hamstring muscles can result in greater strain being placed on the quads, which can lead to muscle-pull symptoms there, especially after running long distances.

If you have tight quadriceps, it will be difficult for you to touch your heel to your buttock while lying face-down on the floor and using the hand on the same side as your ankle to pull it in. If tight hamstrings are an issue, lying face up on the floor with one leg bent to your chest, you will have difficulty straightening the knee.

There are a multitude of other reasons you could be experiencing this pain. An accurate diagnosis from a sports physician is the first step in avoiding a recurrence.

Brian L. Bowyer, MD, Columbus, OH

While other factors may be important, I believe you primarily need to strengthen the quads and some of the recommended drills (skipping, bounding) have more to do with increased muscle resiliency than strength. I suggest you also start a weight training regimen.

Michael Yessis, PhD, Escondido, CA

The marathon course can also be a factor in quad discomfort. A downhill course, like Boston, kills quads later in the race for those who haven't adequately trained on hills.

Melvin Williams, PhD, Norfolk, VA

Please note that Clinic responses frequently appear as excerpts of longer answers, especially when the inclusion of two full answers would result in redundant information.

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