The relation between maximal running speed and body mass in terrestrial mammals

The available data on maximal running speeds of mammals are presented, and the relationship between speed and body mass is considered. For all mammals ( n = 106), maximal running speed scales as (body mass)^0–17; however, the largest mammals are not the fastest, and an optimal size with regards to running ability is suggested ( 119 kg). Maximal running speeds are, on the average, somewhat more than twice maximal aerobic speeds.
Within the Artiodactyla, Carnivora or Rodentia, maximal running speed is mass independent, in agreement with theoretical expectations for geometrically similar animals (Thompson, 1917; Hill, 1950). McMahon's (1975 b ) model for elastic similarity is therefore not supported by the available data on maximal running speeds, and there appears to be no necessary correspondence between scaling of limb bone proportions and running ability.