Leg extension
Exercise technique:
You are seated at the back of the seat, your feet parallel to their locations behind the tubes. Make sure you have your back securely in the seat. The exercise consists of extending the knees while retaining the descent well. We will hold on to the handles provided to stabilize ourselves and not take off the buttocks.
Muscles worked:
Main: quadriceps
Sitting (hips bent) prevents the rectus femoris from contracting forcefully. It is therefore the vast ones that are the most in demand.
You can, if you want to work the anterior rectus more and if your machine allows it, tilt the bench so that your hip is less flexed. In this way, your earlier right will be more stretched.
Interest of the seated leg extension
This is an exercise that can help define the thighs. It will also allow you to work in a localized and specific way after one or during a phase of rehabilitation.
Variants of the seated leg extension
The exercise can be done with open feet (duck-like) in which case the vastus medialis will be more strained.
It can also be done with the feet facing in, in which case the emphasis will be on the vastus lateralis.
Either way, these “rotations” should be used with caution and always done from the hips (the thigh being completely in line with the motion and not just the leg from the knee).
Danger / contraindication to seated leg extension
Be careful not to lift the buttocks off the seat. This happens when we want to force, because the anterior right is shortened at the level of its two insertions during the negative phase.
By lifting the buttocks off, it regains length at the hip and is thus able to contract with force to the detriment of the health of your back since by lifting your legs the arch of the lower back will be strongly accentuated.