The Hamstring’s Role In The Deadlift
The hamstrings play an interesting role in the deadlift. They are a primary hip extensor, which is an extremely important role in a hip hinge dominant movement. But less talked about is the hamstring’s role in the anti-extension of the knee joint. The hamstrings act against the quadricep in the role of knee extension, and when utilized correctly it helps to stabilize the knee joint and prevent the knees from locking too soon. But when the hamstrings are inefficiently used in the deadlift, in this case over biased towards, what we can see from Matt’s deadlift (CLICK HERE) is this battle between the hamstring and the quad with the hamstring winning. Now at the same time though, if we bias too much the opposite way anteriorly towards the quads, the scenario we see then is the hip shoot deadlift where the knees immediately lock and the lifter ends up looking like they are doing a stiff leg deadlift. So in summary, there needs to be this perfect happy medium between the hamstring and the quads to create the most efficient deadlift.
The first video is of Matt’s 661lb. PR deadlift from this past week, with some major form improvements all around. Notate how there is distinct leg drive to initiate the bar breaking from the floor, followed by the knees locking and the hips extending. In the sumo deadlift especially, we want to see this distinct knee lock and hip lock in that order. It is a fairly quick action, with the knees locking preceding the hips locking by a fraction of a second. In this example of Matt’s deadlift, we see the hamstrings working conjointly with the quadriceps to optimize the mechanics of the knee joint.
In the second video from a couple months back we see what happens when the hamstrings become too dominant within the sumo deadlift. Matt was biasing towards his posterior chain, and if you were to zoom in and watch in slow motion you could see this even before the bar left the floor through the pressure of his foot (rocking back towards his heel and “twinkle toes”). As the bar breaks the floor the hamstrings and quads fight against each other, with the posterior bias he displays emphasizing tension on the hamstrings. But his body is wanting to bias more towards his quads to find the more efficient position. This can be seen in the “leg shakes” that occur right after the pause. His quads are trying to extend the knee but the hamstrings are not fully allowing it. And then by lockout, you can see that as he fully extends at the hips his knees unlock yet again due to the hamstring trying flex the knee and overruling the quadricep.
So what was the fix for this? It sounds simplistic, but it mostly comes down to foot pressure off the floor. If we get that right, most of the time the hamstring vs. quad tensioning will take care of itself. I had Matt initially deadlift barefoot and then proceed to wearing slippers rather than shoes, as this helped to establish a better connection to the floor with the foot. From there we emphasized a more patient pull, developing tension pre-pull by driving the knees forward and out as he pulls the chest up. He uses the patient tension build to find the correct pressure at his mid-foot and leverages the bar to pull his mid-foot directly into the floor.