Runners who train at a high level invariably find themselves injured from time to time. The purpose of this column is to explain how to get back to 100% as quickly as possible. The first key to minimizing down time is realizing when rest is required. Here are the rules of thumb that I have acquired from 39 years of running and coaching. Rest is required if any of the following criteria are met:

--Leg soreness gets worse during the course of a run.
--Normal running or walking is impossible or very painful.
--A knee is swollen.
--A running problem has gotten worse from day to day.
--Muscles, tendons, or joints have been sore for a full week.

It is tempting to try to "run through" a problem by taking large quantities of aspirin, ibuprofen, or other anti-inflammatories, but I have gradually come to the conclusion that those things mask the problem and just delay the inevitable. It is best to rest while the problem is relatively small and manageable, rather than toughing it out until the problem is major.

Once it is determined that rest is required, the next step is to get pain-free. During that time it is important to maintain aerobic conditioning through exercises that don't aggravate the injury. My favorites are biking, swimming, deep water running, and long walks. Once pain-free, it is tempting to jump right back into training, but that is not a good idea. Instead, you must give your body time to recover, and then start back. The number of pain-free days that you should have can be found on the following schedule:

Open runners -- 3 days pain-free
40-49 -- 4 days
50-59 -- 5 days
60-64 -- 6 days
65-69 -- 8 days
70 & Up -- 10 days or more

After the required number of pain-free days is completed, the total number of days rested should be calculated. That is the amount of time that should be used to build back to full mileage and intensity. For example, suppose that a 52-year-old runner has nine rest days with pain, and then five days pain-free. The recovery schedule should then be 14 days. After 14 days, everything should be back to normal, and it should be possible to train and race at full speed.

Here are a few additional tips about some common running injuries.

Stress Fractures of the Foot or Leg These will rarely show up on an X-ray, and a bone scan may be required. It is almost always necessary to take six weeks off from running, but alternative exercises such as biking and swimming should be no problem.

Back Pain and Stiffness One might be tempted to visit an orthopedist, but they basically know how to 1) prescribe drugs, and 2) do surgery, neither of which is likely to solve the runner's problem quickly. I have had better results with chiropractors and massage therapists. If there really is a major problem, then a visit to the orthopedist is a last resort.

Piriformis Syndrome This is an inflammation of the sciatic nerve where the hamstring connects under the buttocks. The key to this is very diligent stretching. For example, if the right piriformis is affected, lie on the floor on your back and grab the top and outside of your right ankle with your left hand. Put your right hand to the outside of your right knee. Now use both hands to pull your lower leg across your body toward your left shoulder, and hold the stretch. You should feel it where you are hurting.

Calf Injury These are delicate, and you have to be careful not to start back too soon. It is best to double the pain-free days in the above chart, to be safe.

Plantar Fasciitis This is a very common running injury, and results in a lot of pain under your heel, as though you have a "heel bruise." It will feel worse right when you get out of bed in the morning. The long-term cure is based on making sure your calves and Achilles tendons are flexible enough. As soon as I have any heel pain I immediately get very serious about calf stretching--several times a day. It's also good to massage and flex your heel before you get out of bed in the morning. Orthotics can also be of help for some runners.

Achilles Tendinitis You can usually run through this injury, as long as you don't do speedwork or steep hills (but not if the criteria at the top of the column are met!). The key is to put two inner sole heel pads under the heel of the affected foot. Wait until the pain is gone, and then a little bit more, and then use just one pad. Again, wait until the pain is gone, and then a bit more, and then go back to no pads. Wait a few days to make sure everything is OK, and then gradually reintroduce full intensity.

Hamstring Pulls It is also often possible to run through mild hamstring pulls by avoiding speedwork and training at a slow pace. The key to recovery is stretching out the muscle and regaining full range of motion. Stretching several times a day can quicken this process.

To summarize, coping successfully with injury requires 1) not being in denial about the existence of the injury (masking it with anti-inflammatories), 2) not being too stubborn to take time off, and 3) patience in the recovery, being willing to go by the body's timetable rather than your own. By resting before the problem gets really serious, taking enough time off to heal the problem, and doing the right things to address the root cause of the problem, you can usually be right back in the swing of things very quickly.

Roland Rust coaches a handful of dedicated runners. (Look for his coaching and running resume.) He can be contacted at rrust9@comcast.net.