The basic function: Moving upright on both legs
Only those who understand how a person should move in a situation and how they actually move can develop functional strategies from this. A look at anatomy books shows that humans seem to move only in a sagittal axis. Frontally and transversely, they describe muscles - if at all - only very statically.
The most important function of a human being is not to lie or sit on the stomach, back or bottom, but to move around. And in the most effective way: upright on both legs. In this functional movement it is useful to keep in mind the task of the muscles. Because from this a specific and sport-dependent consideration is possible.
The example leg flexor
Even the naming shows how isolated this muscle has been considered so far. Sure, it bends the leg when standing or even lying down. But who has ever strolled along a street and deliberately bent the leg flexor?
Gym goers lie in the prone position on a "leg curl machine" costing several thousand euros. Such a device is extremely effective for muscle building, but not functional. Two things are missing: the frontal and the transversal axis. So, in that sense, there would have to be three different leg curl machines to complete the movement. Because every joint in the human body, without exception, functions in three axes and should be moved and trained in all of them from a functional point of view.
A little more precisely: The leg flexor or better hamstring - like all other muscles by the way - does not work in isolation, but is part of a whole muscle group. The group consists of semimenbranosus and semitendinosus (the two inner/medial heads), as well as biceps femoris with the long and the short head as the two outer/lateral heads. The first three attach to the pelvis at the tuber ischiadicum. The biceps femoris with the shorter head originates at the posterior part of the femur. The semimenbranosus runs to the medial part of the tibia and the soft tissues of the posterior medial part of the knee. The semitendinosus runs more to the anterior medial portion of the tibia, but the biceps femoris runs to the outer portions of the fibula head (fibula).
The leg flexor elongates
On the lower leg, it seems like the hamstring just wants to transversely hug the lower leg from behind. Does that make him the knee twister now too? When we are about to put the left foot in front of the right, the pelvis tilts forward. This means an elongation of the hamstring at the hip joint, i.e. those three heads that attach to the pelvis.
Lengthening is the "load", the eccentric stretching of muscles in preparation for the concentric phase ("Explode"). When our left heel hits the ground, the knee bends due to the force of gravity of our own weight and our own acceleration.
The leg flexor works exconcentric
Anatomy books know exactly three possibilities for the working of the musculature:
But how does the hamstring actually work according to the above description?
In the sagittal plane during a forward movement: EXCONCENTRIC!
Here's what happens in the frontal plane:
In the third, the transversal plane, the following takes place:
The bottom line?
There is no device, nor will there ever be, that will fully account for the incredible function of this muscle! Train smart, Train functional with PAT!
Article was originally published in Functional Training Magazine on 07/05/2014.