Leg Press, important muscle group for skiing well.

Since I am working on my calf, push off muscles, as well as my legs, my feet are lower than normal to put pressure on the toes and ball of the foot. If you want more glute (butt) and quad training, move your feet forward or up the ramp.

This is just one of the many types of lower back "safe" leg press machines. It works reasonably well and you don't need a spotter or years of squat technique training..