Trainer has feet feeling the burn

After about 20 minutes of working out on the elliptical trainer, my feet start burning. I’ve tried new shoes and socks. What causes this?

TERESA

Pasadena

Your problem has to do with nerve pain, says Dr. Doug Richie, a Seal Beach-based podiatrist and past president of the American Academy of Podiatric Sports Medicine. “It’s from the concerted, unchanging pressure on the ball or the heel of the foot. There’s no changing or shifting of pressure as with walking or running.”

Most who use ellipticals or stair climbers use the balls of the feet to move the pedals. Those pinched nerves, he says, “don’t do well when they have constant pressure applied on the same spot minute after minute,” and often react by creating that burning sensation you feel.

The remedy is simple; Richie suggests being more conscious of the position of your feet when you’re on the machine. Make sure to keep your heels down to distribute the stress over the entire foot, not just the ball.

Arch supports in your shoes might help as well. “It helps dissipate pressure to a wider area, especially the arch that isn’t sharing and bearing the weight,” Richie says.

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I had an arthroscopy on my right knee two years ago, and I have a similar problem with my left knee. I can neither squat nor run. What’s your advice? How should I cope with it? Is biking good for me?

MOHAMMAD

Woodside, N.Y.

Your previous surgery shouldn’t put the kibosh on exercise, says Dr. Edward Toriello, a Queens, New York-based orthopedic surgeon. Exercise is essential, he says, to “keep the mobility and strength of the knee joint as high as possible, within your limits. A joint surrounded by strong, toned muscles will do better than if it were surrounded by weak, atrophied muscles.”

The first line of defense (if you haven’t already done it) should be physical therapy to help maximize the amount of flexibility in your knee.

Assuming you’ve gotten the go-ahead from your doctor to exercise, Toriello suggests avoiding high-impact workouts that put too much stress on the knee, as well as ones that require the knee to bend a great deal.

For cardiovascular exercise, try swimming, walking or using an elliptical trainer or cross-country ski machine, and start slowly before gradually building up to longer and more intense sessions.

You can try cycling, but Toriello says it’s important to make sure you are properly fitted to the bike, whether it’s a road or stationary bike. If the seat is too low, your knees will be bending too much -- too high, and you’ll have trouble reaching the pedals. While you sit on the bike with your foot on the bottom pedal, your knee should be slightly bent. If you decide to take a group cycling class, keep in mind that those can be intense, especially if you’re in the early stages of exercise.

Weight training -- including squats and lunges -- isn’t out of the question, but use common sense and stop if you feel any strong twinges or pain. Try shallow squats (going down only about 30 to 40 degrees) using light weights.

How to know if you’re overdoing it? Toriello says that if normal activities such as walking up a flight of stairs is tough the day after exercising, you’ve done too much. Some muscle soreness is OK, as long as it doesn’t curtail your regular activities.

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