Running improves both your physical and mental health, requires no fancy equipment, and can be done almost anywhere. But the benefits to your waistline, your cardiovascular system, your leg muscles and your mind don't come cheap. If you run regularly you're almost certain to experience aches and pains from time to time. Pain in the inner thigh, or groin, on the left or right side can interfere with your training or halt it altogether. Consult a doctor to get an accurate diagnosis.
Anatomy
Your inner thigh includes five adductor muscles, three short ones and two long ones. All originate in the pelvis. The pectineus, adductor brevis and adductor longus make up the short adductor group and insert on your femur. The gracilis and adductor magnus are the long adductors and insert on your knee. The function of these muscles is to draw your thighs together. Sitting with your legs apart, placing your hands on your knees and pushing inward with your thighs against the resistance of your hands calls the adductors into play.
Sports Hernia
Formerly known as Gilmore's groin and sometimes called athletic pubalgia, a sports hernia typically occurs on the left or the right side, although you may sometimes feel pain on both sides. The pain tends to be dull while you're running at a steady pace, but may be sharp when you accelerate from a standstill. Your hernia may be acute or develop over time. A sports hernia, like other types of hernias, results from weakness in your abdominal wall. It is caused by shearing forces on the adductor muscles where they attach to the pubic bone. Rest alone sometimes solves the problem. However, surgery may be required, so consult a physician if you suspect a sports hernia.
Osteitis Pubis
Osteitis pubis is inflammation of the pubic symphysis, where the left and right pubic bones meet. Symptoms include sharp or dull pain and tenderness that tends to come on gradually. Discomfort is most often felt in the middle of the pubic bone, but often extends to the left or right inner thigh. Stress overload in runners with a biomechanical imbalance such as a leg-length discrepancy is the most common cause. Rest and icing provide immediate relief; strengthening and stretching exercises reduce the likelihood of a recurrence. Your doctor can refer you to the appropriate professional, most often a physical therapist, so that you can work with her to develop a specific treatment plan.
Tendinitis
If you have groin pain while running that radiates down your left leg and worsens when you accelerate quickly or change direction, you may have adductor tendinitis -- inflammation of the tendons connecting the adductors to the pelvis. Unlike a tear, pull or strain, adductor tendinitis is most often an overuse injury rather than the result of trauma. Treatment includes rest, icing the area and, if your healthcare provider recommends them, anti-inflammatory drugs and rehabilitation exercises.
