As with any sport, there's a degree of risk for injury involved with cycling. Endurance sports, such as cycling and running, require repetitive motions over a long period. This can lead to overuse injuries if body alignment or movement is even slightly off. Possible causes of hip pain in cyclists include bursitis, snapping hip syndrome, impingement syndrome, labrel tears or piriformis syndrome. If you experience hip pain that worsens or doesn't go away, see your doctor for treatment.
Causes and Prevention
Your diagnoses may vary, but the causes of cycling hip injuries are usually similar and involve over-training and muscular imbalances. For example, piriformis syndrome is caused by overuse of the glutes, which results in a weak, tight piriformis muscle that causes sciatica.
To avoid such problems, warm up and stretch your hip flexors, piriformis and glutes when you ride. Also, engage in resistance training exercises regularly to prevent muscle imbalances that can result from the repetitive pedal motion.
And have your bike professionally fitted to make sure there aren't any issues with your posture or pedal stroke -- such as rocking of the hips -- which can cause hip pain and injury.