If your hamstrings are tight, you will probably notice a consistent, downward, pull on your pelvis. And because the pelvis is the foundation of your lower back and spine, tight hamstring muscles contribute to lower back instability. This instability, in turn, can lead to greater risk of intermittent strains.
A simple way to check to see if you have short or tight hamstring muscles is to lie flat on your back and have someone help you slowly raise one leg, making sure that your leg is completely relaxed. Do not lift the leg with your own muscles. Generally, if your leg can be raised to 90 degrees angle from the ground straight up toward the ceiling, without any major tightness along the hamstrings, then you are fine. But if you start to feel tightness before reaching 90 degrees, it is a good sign that you need to pay attention and stretch your hamstrings often to relieve the tightness or pain.
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Tight Hamstrings and Lower Back Pain
