About a month ago I tried to sweat out the stress of a bad day by crushing tennis balls. The result: tennis elbow (formally, lateral epicondylitis), an acute pain on the outside of my forearm just below the elbow every time I lift something. Tennis, ironically, accounts for only 5 percent of cases of tennis elbow. Overdoing any of a host of activities that involve repetitive arm movements -- like pitching, rowing, raking or hammering -- can produce the same result.

My error? I failed to warm up properly, which relaxes the muscle and sends blood where muscle, tendon and arm bone meet. (Warm muscles and tendons are less likely to strain and tear than cold ones) Then I compounded the problem by over-hitting the ball, which caused small tears in the tendon.

Tennis elbow is most common in people age 35 to 50 because they lose elasticity in their tendons, says Carl MacCartee, a Washington orthopedic surgeon who has worked with dozens of professional athletes. "In your twenties, the tendon stretches and comes back," said MacCartee. "As you age, it tears more easily."

The condition is less common in folks over 50, said MacCartee, because they lack the power to put injury-causing strain on the tendon.

Three muscle groups that control the wrist and fingers originate at that muscle-tendon-bone juncture in the forearm. This explains why tennis elbow sufferers wince when they tighten their grip, for example, when lifting even a coffee mug.

So what was I to do? Fellow athletes offered me a litany of sometimes-conflicting advice:

* Stop playing for a month. Or keep playing, but take ibuprofen in advance.

* Get a shot of cortisone, a steroid that can reduce swelling and pain for weeks. Or don't get a cortisone shot whatever you do, because it will mask the pain and allow you to further tear the tendon without realizing it.

* Ice it every day. (No counterpoint to this one.)

What do doctors advise?

First, patience: Even with proper treatment, tennis elbow can take up to four months to heal. Re-conditioning exercises help to speed recovery. Nonsteroidal anti-inflammatory drugs (like Advil, Tylenol and Aleve), which circulate in the bloodstream, won't likely provide much pain relief because so little blood gets to the hot spot. Want something more effective? "There is nothing wrong with a little cortisone," said MacCartee. Problems arise, he said, when patients think cortisone is the cure. "You see people getting cortisone shots every six weeks and they trash their elbows because they refuse to do the stretching and strengthening exercises needed to help the area heal."

Repeated cortisone use can break down the tissue around a damaged tendon, warned Jeff Bauer, associate professor of biomechanics at the State University of New York at Cortland.

To stretch an injured tendon, MacCartee recommends: Hold your arm straight out in front of you, point your fingers toward the ground and rotate your palm inward (i.e., so that your thumb is pointing away from you). Do this exercise three or four times, holding each for five seconds. To strengthen the tendon, do wrist curls with a three- to five-pound dumbbell. Ice the area after intensive use.

Also, reduce the frequency and the length of time you stress the tendon. "You don't want to play three days in a row without letting the muscle and tendon recuperate," MacCartee cautioned. "Most people are not willing to give it time to heal."

When you play, warm the muscle up by hitting easy at first, to get blood flowing to the area.

I have found moderate relief from wearing a Velcro-strap armband. "None of [the bands] works really well," MacCartee said, "but they do help" by compressing the muscle and tendon just before their joining point; this dissipates some of the force as it travels up the arm.

If your pain does not decrease after about a month, you probably need to adjust how you hit or change your racquet, strings and/or balls: All can affect how much impact reaches your elbow.

Volley online this Thursday at 11 a.m. for the Moving Crew chat at www.washingtonpost.com/wp-dyn/liveonline/health/movingcrew.

-- John Briley