SIMULATING REDUCED GRAVITY - A REVIEW OF BIOMECHANICAL ISSUES PERTAINING TO HUMAN LOCOMOTION

In the decade preceding Apollo missions to the Moon, extensive studies were conducted on human locomotion in reduced gravity. These investig ations focused primarily on issues of maneuverability and energy expen diture and not on musculoskeletal loading, which is of more interest t o planners of long-duration space missions. The techniques have includ ed water immersion, parabolic aircraft flights, supine and erect cable suspension and centrifugal methods. The practical implications of the findings from these studies are: 1) the present shuttle treadmill run ning surface would not suffice if one wanted to run with a natural sty le at levels greater than 0.6 G; 2) in terms of attempting to replicat e typical ground reaction force profiles during locomotor exercise at reduced gravity levels, it appears as though it is easier to match the peak rates of change of force ((max)DFDT) than it is to match values for the peak force magnitudes ((max)GRF).