The hamstrings are a major group of muscles in the upper leg. Sports and every-day activities can leave the muscles tight from use and in need of a good stretch. Experiencing hamstring pain when trying to stretch the muscles may not necessarily be a sign of injury, but be sure to check with a healthcare professional to determine the exact cause if pain persists.
The Bits and Pieces
The hamstrings consist of three major muscles at the back of the thigh: the semitendinosis, semimebranosus, and the biceps femoris. These three sections originate at the bottom of the pelvic girdle and attach to the tibia and fibula of the lower leg behind the knee. The hamstrings allow you to extend your leg straight behind you as well as bend your leg at the knee.
When Things Go Wrong
The American Academy of Orthopaedic Surgeons explains that hamstring strains or tears occur when the muscle experiences overload and is stretched beyond its capacity. Strains or tears cause inflammation and internal bruising in the muscle which will cause pain when the muscle is stretched. If you’ve experienced sharp pain in the hamstring during activity prior to stretching see a medical professional immediately to rule out the possibility of strain, tear or rupture of the muscle.
The Pesky Piriformis
Hamstring pain while stretching can sometimes be the manifestation of tightness or compression in tissue other than the hamstrings. The pain may feel as though it’s coming from the hamstrings but can sometimes be traced to the piriformis muscle or sciatic nerve instead. According to a 2007 study performed by Dr. Lori Boyajian-O’Neill that appeared in the the "Journal of the American Osteopathic Association," the sciatic nerve passes directly through the piriformis muscle in as many as 22 percent of adult individuals. In many of these cases, any inflammation of the piriformis muscle results in compression of the sciatic nerve. The resulting pain may emulate symptoms of sciatica that often include pain down the hamstring, especially when bending forward. Piriformis syndrome can occur whenever activities -- such as long distance running, sprinting, or sports with frequent changes in direction -- stress the piriformis muscle and surrounding tissue.
Change It Up
If your healthcare provider has ruled out injury as the source of pain while stretching, a few modifications to your stretching techniques may help alleviate some of the discomfort you may be experiencing. Performing lying hamstring stretches can alleviate stress on muscles like the glutes and the piriformis that may be stressed or compressed in a standing or seated position causing what feels like pain in the hamstrings. While lying on your back, pull one knee in towards your chest and grasp the back of the thigh with both hands. Gently straighten the leg as far as you’re able, maintaining the grasp on the back of the leg. Hold the stretch for 30 seconds and repeat on the opposite leg. Slowly rolling the back of the thigh along a foam roller can also stretch and release tight hamstrings without putting stress on other muscle groups that may be contributing to hamstring pain.