I am a 34-year-old woman athlete who likes to compete in triathlons. I recently developed pain in the front of my knee and was diagnosed with ''Jumpers knee.'' What is this? And what part of my training is causing it?

Jumpers knee is an inflammation of the patellar tendon as it attaches to the lower end of the knee cap (patella.) Excessive stress on the patellar tendon where it attaches to the patellar bone can result in microtears of the tendon fibers. The microtears of the patellar tendon can lead to inflammation and pain. Continued stress can result in deterioration and further breakdown of the tendon fibers. More than likely, the running portion of your training is the source of your symptoms. Several factors such as training errors, differences in shoes and surfaces and variations in anatomy alignment have been identified. Of these factors, training errors, particularly rapid transitions in training, are responsible for these injuries. Most knee injuries can be resolved with conservative treatment. Surgery is sometimes needed.