What causes tight hamstrings?Here's a few different reasons for the common complaint of hamstring tightness.
Working as a massage therapist, I often get clients coming in with “tight” hamstrings. Along with the concern of constant tightness, no matter what they try. But are the hamstrings really the issue? There's more to restricted hamstring mobility than just the muscle being tight. Here's a few different reasons for the common complaint of tightness.
One common reason for complaints of hamstring tightness is not really the fault of the hamstring at all- it's due to the pelvis. Some people develop what is known as an anterior pelvic tilt. It can be hard to understand, basically the front of the pelvis tilts forwards and down. This motion causes the attachment of the hamstring at the ischial tuberosity (part of the pelvis) to become further away from the attachments at the knee, causing the muscle to lengthen. As a result the hamstring will eccentrically contract which causes that tight feeling. The best way to improve this tightness is to correct the pelvic tilt! Which means stretching to the hip flexors and quads, and strengthening to the core and gluteal activators.
Another reason people often feel tightness in their hamstrings is neural in nature. Meaning it's not the muscle, but the nerves causing the feeling of tightness. This can occur in the lower spine or into the gluteals where the sciatic nerve passes. If there is damage or entrapment of the nerve, it can inhibit proper nerve function and cause the feelings of tightness, pain, numbness or tingling. Massage and other soft tissue techniques can help to release entrapment or compression of the nerve.
Previous injury can also cause the feeling of tightness. If scar tissue has developed in the muscle fibres, the hamstring will not lengthen efficiently at this level. This is often frustrating for those who have developed a scar tissue build up, particularly at the ischial tuberosity where the hamstring attaches to the pelvis. This is a common area for scar tissue to develop, and traditional stretching is often not enough to release the tissue. In most cases, restricted range of motion due to build up needs to be removed by soft tissue techniques. Once the scar tissue fibres are aligned as much as possible, clients usually feel a decrease in tightness and improved range of motion.
Now for when your hamstrings actually are tight: This can be found in people that are sitting for long hours of the day. When sitting, the pelvis is more likely to go into a posterior pelvic tilt where the pelvis rotates backwards. This posture, along with a knee bent while sitting, is where most people will have actually tight hamstrings. Although many jobs require sitting for large portions of the day, truly tight hamstrings isn't very common. If you aren't able to relieve any tightness with simple direct stretching, it is likely your hamstrings feel tight for one of the reasons above.