NOT KNOWN DETAILS ABOUT HIP THRUST

The two higher than seem strange to me. They can be practically the one details on which each and every video clip I have found do concur (as in "do bend your knees, do lift your heels") Hinging without bending the knees / transferring the hips down ? How ?Contrairement à des exercices populaires comme le vélo stationnaire ou le tapis roulant, le