With the Deadlift and the Bench Press, the squat belongs to the most popular exercises.
If he works mainly the Quadriceps femoris and the glutei, he also requests many muscles of maintenance (in particular Adductors, abdominal and Hamstrings), and develops also the cardiovascular system.
To practice this movement with the machine makes it possible to isolate the Quadriceps femoris.

Position of the body :

Upright, the quite right body and slightly spread legs (with width of shoulders), the feet in parallel or pointing slightly towards outside. The bar must rest on the trapezoids (in bottom of the nape of the neck) or a little low (position of power-lifting, which makes it possible to take heavier).

Position of the hands :

Overhand grip. The spacing must be important (according to morphology and the flexibility) and the drawn elbows backwards.

Movement :

To inspire deeply and camber the back slightly (by pushing the basin behind), to contract the abdominal strap to help to maintain this position. To descend the bar by bending the legs and by inclining the back forwards, without never rounding it.
Once the thighs with horizontal, to carry out the movement reverses while pushing on the legs and to rectify the back of them. To go down more makes it possible to work the glutei more but increases the risk largely to round the back, and thus to be wounded.

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