Musculoskeletal Loading via Running with Loads during Simulated Gravitational Transitions: Improvements in a Precision Stepping Postural Control Task

The National Aeronautics and Space Administration is preparing for long-duration manned missions to the Moon and then Mars. To enable these voyages, improvements in exercise countermeasures are required to preserve cardiovascular fitness, bone mass, and the ability to perform coordinated, bipedal locomotion movements following “near weightless” travel and orbit periods. Gravitational transitions require rapid recalibration of feedback and feed forward postural control strategies to ensure safe, effective performance. The results of this study suggest strategies for maintaining critical locomotion abilities following transitions between gravitational acceleration fields.

A novel suspension-type partial gravity simulator incorporating spring balancers and a motor-driven treadmill was used to enable bodyweight off-loading and a unique precision stepping task. This device and postural control task induced locomotor adaptations resembling those experienced by astronauts returning from spaceflight and proved to be sensitive in identifying alterations in performance. Musculoskeletal loading in the form of running with backpack loads improves the locomotor adaptation process such that higher loading levels appear more effective than lower levels.