The hamstrings will primarily originate at the tuberosity of the ischium and insert at the tibia and fibula. The hamstrings are a muscle that is commonly tight amongst most people who are often stationary in a seated position.  If we analyze what a seated position looks like, we will see knee flexion happen.  Although there is a direct correlation of dysfunction based upon the seated position alone, the main problem is really what is happening at the hip flexor complex.  

When hip flexor tightness is present, it will automatically inhibit the activation of the gluteus maximus at the opposing end of the hip.  When the gluteus maximus is incapable of working, the hamstrings then be the site of compensation.  You will get an overuse of the hamstrings there after because they have been compensating, consequently making them tight and restrictive in their movement capabilities.  

The hamstrings will play a role in ruining an efficient standing posture, via knee flexion.  Since they have been wired of their capabilities to extend the hip via tight hip flexors, the will then have to rely upon knee flexion as a secondary response.  The most common functional restriction found is the eccentric phase of a squat.  The hamstrings are crucial in deceleration, so any inhibition of their shock absorption capabilities will have major consequences


To start we will sit on a flat seated chair and place the lacrosse ball underneath the thigh. It is best to keep the knee in flexion so that the ball can settle in to the hamstrings. After it has set in place, we will extend the knee as a form of active release via the usage of the quadriceps muscles.