Most endurance athletes would benefit from strengthening their gluteus medius. Here’s why:

– WEAKNESS. Most training for running, cycling, and even swimming are in the front to back directions. You will get very strong in the front to back plane, but the lateral plane stays the same in terms of strength.
-STABILITY. The whole position of your leg depends on the muscles that support it at the hip. If something is turned or rotated here how can you expect the rest of your leg to be in good alignment? Your gluteus medius is the muscle that is responsible for all of the lateral stability and external rotation. Weakness here causing the knee to collapse towards the midline, and the foot to overpronate. This usually presents as a knee or lower leg issue.
-PREVENTION. Weak gluteus medius is the most common finding in running injuries. Trochanteric bursitis, IT band syndrome, knee pain, patellofemoral pain syndrome, plantar fasciitis, and posterior tibialis tendonitis all are correlated with gluteus medius weakness.
Here are my three favorite gluteus medius exercises exercises (pick one to do before running for prevention!)