If u wanne do the quads! Find a box and just climb it. The higher the better. If it feel to easy, hold barbels inyour hands or do it more explosive and create a jump. One leg at the time. Up down up down up down...no stress for your back! Since Im into cardio now (cycling before, now running every second day) my body is to weak to put wieghts on the shoulder, dosent like it anymore. So one leg squts on a box feel great : )
