With US astronauts Butch Wilmore and Suni Williams set to return to Earth this week, Brock University Associate Professor of Kinesiology Val Fajardo (BSc ’09, MSc ’12) says their first steps back on the planet might be a bit rough.

“Regarding long-duration spaceflight, we know that there will be decrements to musculoskeletal health, including bone and muscle deterioration due to microgravity exposure,” he says.

Fajardo is a nationally recognized expert on muscles. As Canada Research Chair in Tissue Remodelling and Plasticity throughout the Lifespan, he studies physiological processes that fuel muscle development or decline, including the impacts of exercise and good nutrition on muscle strength.

He and his team have also received samples and/or funding from NASA and the Canadian Space Agency to study ways to prevent astronauts from experiencing bone fragility, cognitive decline, and muscle loss and weakness, which occur when spending time in space.

Their research has mainly focused on studying tissue samples from mice that spent time on the International Space Station (ISS), which is where NASA astronauts Wilmore and Williams are stationed.

Fajardo says rodents and humans lose muscle and bone density and strength at a much faster rate in space than they do on Earth because of reduced gravity, which quickly leads to deterioration or atrophy.

The NASA astronauts in question — who were only intended to be aboard the ISS for eight days — have been in space for more than nine months.

Fajardo and his teams’ research provides some valuable insight as to what Wilmore and Williams can expect when they disembark the craft.

“The declines in muscle health and function contribute to a reduction in overall aerobic fitness, which some estimate could be equivalent to decades worth of aging here on Earth,” says Fajardo.

“This is why exercise is essential in space; however, research has shown that this alone is not sufficient,” he says. “We need to develop adjuvant therapies if we wish to engage in long-duration spaceflight missions like those to the moon and Mars.”