Hamstring training is a topic that I thought I knew about, that was until I sat in a really interesting lecture 3 years ago.  In this lecture, the speaker, Franz Bosch challenged what I know about the function of the hamstrings and also how I thought about their movement.  (1)

hamstring training

a diagram of the hamstrings

Until this lecture, I though of movement at the pelvis, to equate to the exact same motion at the origin of the hamstring muscle.  However   I unfortunately had not considered the shape of the pelvis and the fact that the origin of the hamstrings were not in line with the pivot point of the hip joint and so what that means when applied hamstring exercises.  When I first qualified as a trainer I would have told you that the best way to challenge the hamstrings to improve their strength for function (not size necessarily), would be to do an exercise that involves a lot of resisted hip extension motions.

Looking now at how the pelvis actually moves, and so how the hamstrings appear to lengthen, it seems that focusing on the muscle was the major problem.  This is because, although we can look at a muscle outside of the body, it is really hard to predict exactly what the muscle does inside the body during movement (2).    Possibly the best way of training a client would then be to focus on how the movements they want to achieve occur, where they occur and what reactions we would expect from the body as this takes place.  For example the role of the hamstrings for soccer player could vary from that of an Olympic lifter, and so you would look to train the soccer player in ways where the hamstrings were active in sprinting (most common hamstring injury in soccer is during sprinting, just before the foot makes contact with the ground or during swing phase depending on which study you read! (3,4)).

I created the following videos to try and show how the origin of the pelvis does not move away from the insertion in a way that you may have been told.  If this is true, then to activate the hamstring concentrically, the motion would be need to be end range if the knees were straight and the exercise was coming from hip flexion to hip extension.  This is not to rule out the other planes, and it is not to suggest that maybe if you get to end range and then travel in several different planes you would not get a reaction from the hamstrings.  However if your goal was to grow the size of the hamstrings, then large range contractions against resistance are where you would aim.

Deadlift – Probably worth making this more like a Romanian Deadlift with straight legs would be better.

If your goal was to improve the performance of your client, in their own function, then maybe the hamstring need to be left to be reactive within the motions you want to improve.  This would mean, rather than trying to work out what they do, it may be better to allow them to just be.

If I was pushed to describe what I thought the role of the hamstrings were, then without the full evidence in front of me, I would suggest that they act as stabilisers at the knee and hip, when the body has little time to react to a motion, in order to be powerful and fast.  For example in a run, where your goal would be for as little floor contact time as possible, I would want the explosive nature of the hamstrings to help propel the motion.  Rapid hopping would be my choice of exercise for a functioning, non specific client.

 

 

 

References (This is not meant as comprehensive list to prove my point, but I wanted you to know I am not just pulling this out of the air)

1 – Running the BK method by Franz Bosch

2 – Evidence-based testing of the hamstring muscles using wireless surface emg by K Kotila, T Sveinsson, and Á Árnason

Br J Sports Med February 2012 Vol 46 No 2

3 – Hamstrings are most susceptible to injury during the early stance phase of sprinting by John W Orchard from

Br J Sports Med February 2012 Vol 46 No 2

4 – Hamstrings are most susceptible to injury during the late swing phase of sprinting by Elizabeth S Chumanov,1 Anthony G Schache,2 Bryan C Heiderscheit,1
Darryl G Thelen3

Br J Sports M February 2012 Vol 46 No 2