Hi guys and gals,
I did a s 3 minute follow up video to the post that I did talking about what to do if a client has ‘tight” hamstrings. this video talks more about rationale and “why”.
Feel free to follow me on You Tube and leave a comment here or on you Tube!
http://www.youtube.com/watch?v=7akPgkRQnEI
Eric Beard
Corrective Exercise Specialist
CEO NASM Pro A-Team
ericbeard.com
2 Comments
Hello,
when doing a squat, the hamstrings are not really lenghtened, aren’t they?
they just change their relative position to the femur under activity.
Or am I wrong?
Hi Fabian,
Good point. Multi joint muscle groups like the hamstrings behave uniquely. During the descent of the squat the hip flexes and knee flexes which could suggest that their is not significant change in length in the hamstrings. Keep in mind however there is more than just muscle at play. The hamstrings are a more effective knee flexor than hip extensor so as the knee flexes, portions of the hamstring are shortening while more proximal portions are “lengthening”. Now is this more of the fascial components that reach up into the sacrotuberous ligament and sacrum? I am not sure. It may just be a superficial view that during hip flexion, the hip extensors change in length, but we could also look at the biceps femoris long head which does not flex the knee. This portion of the hamstring does not flex the knee but does extend the hip and eccentrically decelerates femoral internal rotation, particularly during hip flexion. It does lengthen in the sagital plane on the descent of the squat. It should allow some internal rotation of the femur as well as the hip flexes. Maybe I should have been more specific? A great conversation piece Fabian:)
Eric