The hamstrings are a misunderstood group of muscles. When most people think about hamstring health, the first things that come to mind are usually stretching by touching your toes, standing or seated, or strengthening by seated hamstring curls on a weight machine. Do these stretches/exercises target the hamstrings? Absolutely. Do they teach the hamstrings how they are supposed to behave in functional movements? Hardly.
So this begs the question: what do your hamstrings do and how do we properly train them? The answer: it depends. It depends on what you do. This will look different for a runner compared to a farmer, or a soccer player compared to someone sitting in a desk all day. For the purposes of this post, we’ll keep it in the context of running. Quick anatomy lesson: the hamstrings are a group of three muscles that originate from the ischial tuberosity (sit bone) and extend past the knee, two out of the three on the inside of the knee, the other attaches to the head of the fibula on the outside of the knee.
There are three primary phases for each leg with running: 1) swing phase, 2) loading phase, and 3) push-off phase. The hamstrings have different functions during each phase and it’s important to understand what’s supposed to be happening at each. Also, most of the discussion will focus on the sagittal plane of movement (forward/backward), as this is the most obvious direction to observe. There are movements and forces in the transverse plane (rotational), and frontal plane (side to side) that we’ll touch on, but focusing on the sagittal plane will help keep details a little cleaner.
Swing phase: This is the ‘open chain’ portion of the cycle where the foot is off the ground swinging forward. During this phase the knee should bend as the hip flexes. The hamstring is not responsible for this knee bend, but rather the hip flexors driving the femur forward and momentum of the lower leg created by the push-off. The hamstrings during this phase are partially responsible for slowing down hip flexion as the swing phase ends, but are relatively quiet at the knee.
Loading phase: This is where the fun begins. As the foot touches the ground and body weight is loaded onto the planted foot, the hamstrings become more awake. At the knee, the hamstrings are mainly responsible for keeping the knee stable, not allowing terminal extension too quickly, nor allowing the knee to further flex. (The soleus is mainly responsible for controlling the knee during loading phase, but the hamstrings also assist with this.) At the hip the hamstrings eccentrically control anterior pelvic tilting, which translates to preventing trunk/pelvic flexion and ultimately keeping your upper body upright. The tricky part about this phase is that the hamstrings are responsible for both the knee and hip. As long as the knee and hip are behaving, than all is good, but if there is dysfunction in any of the adjacent joints or muscles, than this can cause a brief, unhealthy, tug-of-war which can quickly translate to a strain or pull.
Push-off phase: At the transition from loading to push-off, the hamstrings act like a catapult helping to propel the hips forward over the fixed lower leg. The hamstrings assist with extending the knee at this point to allow for full push-off. Then the leg is back into swing phase.
Again, when considering hamstring health, it’s most effective to train them in a way that translates most directly to what they need to do for the specific activity. The majority of the hamstrings’ contribution to running occurs with the foot planted on the ground. Because of this, the most effective hamstring exercises are done with the foot on the ground or planted on something, and the upper body mimicking the movements that occur during running. Here are a few examples.
First, a stretch for the hamstrings with rotational reaches to target different parts of the muscles.
Next, a strengthening progression, essentially a single leg deadlift, then hip rotations to strengthen the hip rotators.
Lastly, a variation of the single leg deadlift with theraband around the knee to challenge control in keeping the knee out of early terminal knee extension.
Give them a try or pass these on to someone who may appreciate better hamstring strength or flexibility. Let me know how you do with them!