The pre-participation physical exam is an excellent opportunity to ask about, and to address, previous overuse injuries. The cyclist should be counseled about increasing activity using the "10% rule"--increasing distance and intensity by 10% each week during early- season and build-up periods. Athletes who have a history of overuse injuries should be examined for weakness and flexibility deficits and may benefit from early-season stretching and strengthening programs. A pre and post workout stretching routine is important for continuous pain-free riding.
Weakness of the quadriceps, hamstrings, or hip flexors may be assessed by manually testing resisted extension of the knee, flexion of the knee, and flexion of the hip, respectively. More accurate, quantifiable results can be obtained by performing mechanical isokinetic testing with a commercial machine such as the Biodex System 3 (Biodex Medical Systems, Inc, Shirley, New York). Flexibility of the quadriceps may be assessed by performing Ely's test and comparing the amount of passive knee flexion in each leg. Hamstring flexibility can be evaluated using the popliteal angle or the sit-and-reach test. Hip flexors can be evaluated with the Thomas test, and flexibility of the ITB may be tested with the Ober test.
Progressive strengthening exercises are warranted for patients who have muscle weakness. Initial activities include isometric quadriceps and hamstring exercises, such as quad sets and hamstring sets. Isotonic exercises such as straight-leg extension and flexion are the next phase in strengthening. Finally, patients perform eccentrically resisted knee flexion and extension with weights. Flexibility focusing on the quadriceps, hamstrings, hip flexors, and ITB is important and should be a regular part of a cyclist's training regimen.
As more people seek low-impact ways to improve and maintain their cardiovascular fitness, physicians will no doubt see more patients who have knee pain related to bicycling. By learning a few simple bike fitting techniques, physicians can treat and prevent many common problems of this popular activity.