Running on the Moon

One of the key questions that remains unanswered as we prepare to send humans to other planetary surfaces is the degree to which living and exercising in these reduced gravity environments will provide an osteoprotective stimulus to prevent bone loss that is currently seen on International Space Station missions. 

With support from the National Space Biomedical Research Institute and the NASA Flight Opportunities Program, our research team from the Department of Orthopaedics and Sports Medicine at the University of Washington conducted a parabolic flight experiment to validate the activity monitoring system that was worn by subjects exercising in microgravity.  Nine subjects were tested as they performed a series of locomotor activities with the sensors positioned on the mid-lower back and around the ankle. Subjects were secured to the surface of the treadmill via a subject load device to provide loads similar to those experienced on Earth. Over two flight campaigns, activities were performed in three conditions:  zero, lunar, and Martian gravity.  An image of a subject running in zero-G with a simulated lunar load is shown below. 

With the acquired parabolic flight data, the team is developing classification software to autonomously recognize activities performed in reduced gravity.  Validation of this system would improve the ability to monitor exercise designed to preserve the bone health of astronauts aboard the ISS and on future exploration missions.  Similar methods could be applied to address the prevention of osteoporosis on Earth.