How many times have you bypassed the stairs for the elevator? Little did you know, you've had one of the most effective workout regimens right at your feet. Scour most gyms and you'll find a few stairstepper machines -- and there's a reason for that. Climbing the stairs is great exercise for improving cardio health and building muscles. Stairclimbing targets the glutes, hamstrings, quadriceps and calves and is a low impact on feet and knees. A study conducted in England and Northern Ireland found that sedentary women who took the stairs up to six times a day increased their fitness level, lowered their cholesterol and decreased their risk of cardiovascular disease over a two-month period. An additional study found that men who climbed at least 100 steps a day cut back their risk of death by 20 percent.