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View Full Version : Re: Hamstrings and Gastrocs link



Paolo De Leva
06-08-2004, 01:34 AM
Dear Rick,

I have noticed the same phenomenon last year. I have two hypotheses on
its possible cause/causes. They are not mutually exclusive.

Sit and reach produces what I call "hamstring hyperstretching":

flexed hip + extended knee = hamstring hyperstretching

FIRST HYPOTHESIS
In a hamstring hyperstretching condition, the large tension at the
distal insertions of the hamstring makes their distal tendons very stiff.
These tendons are very close to the tendons of the gastrocnemius. If the
gastrocnemius tendons are not relaxed (shortened, loose), there might be
interaction between them and the hamstring tendons. They might be pushed
against each other. Moreover, if some kind of tissue (e.g. adipose tissue)
were placed between these tendons it would be squeezed. This could produce
pain.
Of course, when you flex the ankle plantarly, you shorten the
gastrocnemius and make its proximal tendons loose. Thus, you avoid the above
phenomenon, even though there's no significant effect in the hamstring
tension and length, and the hamstring tendons remain extremely stiff.

SECOND HYPOTHESIS
I have learned from an anatomy professor that all muscles have some
tendon fibers attached to the joint capsula. Duing knee flexion, e.g., these
fibers keep the posterior aspect of the knee capsula stretched. Thus, they
prevent it from becoming loose and being possibly pinched and squeezed
between the joint surfaces of the tibial plateau and femoral condiles.

When you hyperstretch the hamstring and stretch the gastrocnemius at the
same time (expecially with ankle dorsal flexion, sometimes suggested by
physical trainers), the capsula might be unnaturally and possibly not
uniformly stretched, by hamstring fibers and gastrocnemius fibers pulling
"to opposite parts" (as Newton would write), i.e. proximally and distally.
This could produce pain.

Some physical trainers think that the more painful a stretching exercise
is, the more effective it is. In this case, in my opinion they are wrong. I
always suggest to perform hamstring hyperstretching with plantarly flexed
ankle. By reducing pain, you can more successfully try and inhibit stretch
reflex, which is quite advantageous in this case, as you probably know.

Best regards,

Paolo de LEVA

University Institute of Motor Sciences
Sport Biomechanics
P. Lauro De Bosis, 6
00194 ROME - ITALY

Telephone: (39) 06.367.33.522
FAX/Tel.: (39) 06.367.33.517
FAX: (39) 06.36.00.31.99

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