Land softly on the box in a partial squat position then stand fully upright.
Single leg squat standing on box.
I f necessary the spotter can stand at the side place one hand on your wrist and the other hand just above the elbow keeping the knee of the working leg in line with the long toe squat down until your thigh is parallel to the floor.
Strength main muscle worked.
Test your abilities further by putting a barbell in your arms while performing a free squat.
Get a box or a chair the lower it is the harder the box squat will be and stand on one leg facing away from it.
Squat down until you are sitting on the box then push back up.
Perform 3 sets of 10 repetitions on each leg.
Step back down to the floor to the starting position.