[quote]Iron Dwarf wrote:
Physical priorities… in other words, the way we are designed makes the quads dominant in most movements. Thus, the hams get much less stress.
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We are designed to be balanced with agonist and antagonist pairings working in tune with one another. That is not to say there is a 50/50 distribution of work across a joint but the work allocated to a specific muscle is dictated by the shape and arrangement of the muscle / muscles / tendons, origin and insertion points on the bone, ROM around a joint, which in itself has structural features that will further dictate function and work distribution. One muscle is not designed to be dominant over another muscle when working around a joint to produce smooth pain free movement. It is only when faulty movement patterns persist that these instances arise and become problematic.
The reason why people may be quad dominant is down to activities of daily living e.g. sitting on your arse all day, over time weakens and inhibits the glutes and hams, tightens the Rec Fem, Psoas Major & Iliacus resulting in anterior pelvic tilt etc etc… Ask any regular person to contract their quads and they will more than likely be able to do so however ask them to contract their hams and you’ll probably get nothing as the mind muscle connection is non existent due to among other things inhibition etc…