Ramps or stairs: the choice using physiological and biomechanic criteria.

A study using eight subjects compared the O(2) consumption, heart rate and maximum knee joint angles when climbing stairs or ramps ranging in slope from 10 degrees to 30 degrees . It was found that the physiological cost of stairs is always less than a ramp of equal slope and that stairs with a 6 in riser were usually better than those with a 4 in riser. The values of the flexion at the knee joint were compared with a theoretical analysis by Shinno and found to differ considerably.