Perceived exertion and physiological economy of competition walking, ordinary walking and running

Four competition walkers performed competition walking, ordinary walking and running on a treadmill on two different occasions. During the two walking modes, the subjects performed maximal tests. During running, the session was terminated at a heart rate of 150 beats min-1 or an exertion rating--for either chest or leg--of 5 or higher. The tests commenced at 2.5 km h-1 and the velocity was increased by 2.5 km h-1 every 4 min. Measures of chest exertion and breathlessness, leg exertion, heart rate and blood lactate were taken every 4 min just prior to the velocity changes. The measured psychological and physiological variables were described by monotonously accelerating power functions with exponents around 2 for the perceptual variables at both walking modes. The heart rate growth for competition walking accelerated according to a function with an exponent of 1.7, which is lower than that for ordinary walking (2.0), but higher than that for running which is linear. No significant difference was found between maximal oxygen uptake when competition walking and running were compared. A second test was carried out so as to confirm the cross-over point for the heart rate curves in the two walking modes. The cross-over point for the two walking curves were determined to be at 8.6 km h-1.