These can be a major contribution to lower back problems.
Take a hamstring test?
Lie on your back with your legs stretched out on the floor, arms by your sides. Raise your RT leg towards the ceiling, keeping your foot flexed. If your leg easily teaches the 90-degree angle towards the ceiling, your hamstrings are normal. If your leg reaches further than 90 degrees towards your body your hamstrings are very flexible. Many people suffer with hamstring stretches because they are a muscle group that tightens up quickly. The key is never to push your range of movement, but instead, hold the stretches for 2-3mins to allow time for the tough connective tissue to open up.
YOUR HAMSTRINGS NEED SOME T.L.C