Let’s explore the reasons why your hamstring might feel tight or contracted.
1.) A low back injury or injury in progress will tighten up the hamstrings. The hamstrings influence the position of the lower back by way of their attachment to the pelvis. The body will protectively tension the hamstrings in order to prevent overloading of the lower back structures.
2.) A knee injury or injury in progress will also tighten up the hamstrings. The hamstrings cross the back of the knee to attach to the lower leg. They have a large influence on the stability of the knee. If the risk of further injury to the knee is present the hamstrings will reflexively contract.
3.) Sciatic nerve entrapment or irritation anywhere along it’s path from the lower back down to the foot will force contraction of the hamstring as a protective mechanism.
4.) Weakness of the hamstrings often times presents as a feeling of tightness. As a muscle group that crosses two joints (the hips and knees), the hamstrings have a massive job. Acting as both prime movers and stabilizers they can start to lose the battle becoming weak and hypertonic.
5.) Anterior pelvic tilt puts the hamstrings in a lengthened position. This is like pulling a rope on both ends while playing tug-of-war. The feeling will be that of a tight and contracted hamstring but in fact they don’t need further lengthening (see below).
Understanding the root-cause of these sensations can save you a lot of aggravation. A feeling of tightness doesn’t always equal stretch. In all of the scenarios above, fighting against your bodies protective mechanisms will not bring about a desired result.