Четырехглавые мышцы, или «квадрицепсы», в первую очередь отвечают за сгибание и разгибание бедра в коленном суставе, что позволяет вам выпрямлять колено. Они также помогают стабилизировать коленную чашечку. 

Leg extension is an exercise usually performed on a lever simulator. You sit on a soft seat and lift the soft crossbar with your feet. The exercise mainly involves the quadriceps muscles of the anterior surface of the thigh — the rectus femoris and the broad thigh muscle. You can use this exercise to increase lower body strength and muscle relief as part of strength training.

In bodybuilding there are two effective exercises, sighting and loading the quads is gakk-squats and leg press in the simulator. Thus, answering the question of which of these exercises will be most effective, we will face a divergence of opinion – some athletes will argue that Sakr-squats are better, others that...