The no-hands Russian leg curl is highly advanced. Most exercisers never get to this point,
but with consistent training you’ll be able to perform the movement all on your own. Your
hamstrings will be able to produce sufficient force to reverse your body and raise it to
lockout with no assistance from your arms. When you reach this point, simply place your
hands behind your back. As the set progresses, put your arms at the side just in case you
need to use them to prevent a face plant.