Hi John –
I was looking through Shape magazine online “for fun” and came across this from David Kirsh – some trainer to some stars….. WHAAATT?? Worried about “bulking up your quads”…… not to do a “traditional squat”…. Well, when I do a traditional squat I feel mostly my hams and adductors and glutes. Hams control my speed on the way down, adductors help navigate so my knees don’t go wacko, etc….. I feel my glutes and some quad on the way back up.
Ok – just had to share this with you. Am I right here? Is this advice a bit off? Hope you are having a nice weekend… Michele
First of all be careful of what you “feel” or what a person “feels” in an exercise. People feel all kinds of things
Basically, if a joint is moving then a muscle is moving it. A squat involves, hip extension, knee extension and spinal extension.
In human ascension and descension, the quadriceps and the gluteus maximus are “anti-gravity” partners. Since the knee is extending, the hamstrings lengthen at the knee, but the hip is also extending so the hamstrings would be shortening at the hip, hence hamstrings don’t change that much in length. However, they do fire. Check this linkhttp://moon.ouhsc.edu/dthompso/namics/lombard.htm.
I wouldn’t consider the adductors prime movers in a squat, because only the gracilis crosses the knee and it’s action isn’t as important in hip extension or knee extension. They seem to act as synergists but not agonists. The glute minimus and medius as well as the hip flexors (both single joint and double joint) may have a role in “navigating” your knees, but most likely, actions at the foot and ankle may have a greater effect on the knee.
Remember, whatever muscles act concentrically also act eccentrically. The quads and glutes lower you eccentrically and lift you concentrically in a squat. They are definitely the prime movers at the hip and knee.
Bulky quads come from testosterone, genetics (muscle fiber type), food and heavy loads.
Hope that helps.