You will be surprised how much you can gain from weekly exercise: http://www.amazon.com/Super-Squats-Pounds-Muscle-Weeks/dp/09... and http://www.ironworkout.com/20_rep_squat.htm

And supersquats are extremely short exercise program: you warm up, you supersquat, you go home to eat and sleep.

About 40 minutes for all steps, except for going home. (40/60)*6 is exactly 4 hours. ;)

(if your supersquat weights are huge, you will need full week to rehabilitate)