Pleistocene humans walked as well as modern ones do. From ScienceDaily:
Since two million years ago, with the appearance of the species Homo ergaster, the body mass and the brain size of the hominins have risen considerably. These changes have entailed an important readjustment at the metabolic level, with greater demand for energy to maintain these larger organs.
“However, our results show that the greater efficiency of locomotion was not a mechanism to compensate for this increase in size. That is to say, the changes observed in the width of the pelvis and the length of the lower limbs did not reduce the cost of walking sufficiently to offset the rise in energy cost caused by the increased body mass,” adds Vidal. Paper. (paywall) – M. Vidal-Cordasco, A. Mateos, G. Zorrilla-Revilla, O. Prado-Nóvoa, J. Rodríguez. Energetic cost of walking in fossil hominins. American Journal of Physical Anthropology, 2017; 164 (3): 609 DOI: 10.1002/ajpa.23301 More.
See also: Could Stone Age clubs really kill? It’s a tougher question than at first appears. Just because a fossil human is found with a bashed-in skull doesn’t strictly prove violence or lethality of weapons. So, following in the footsteps of the one-proud maxim of journalism, “If your mother says she loves you check it out,” some researchers wanted to know if Stone Age clubs (in this case, 5500 BC) can really kill.