The International Space Station, not exactly the place you’d expect gym-goers to be. But because of the nature of the environment astronauts find themselves in, exercising is mere survival.

On Earth, human beings have evolved over thousands of years to become used to and take advantage of the gravity and the atmosphere to protect us from the harsh elements of space. However, those astronauts don’t have the same luxury as they have to deal with micro-gravity, limited resources and, if they didn’t exercise, would suffer from great(er) negative symptoms when they returned to earth.

Common Complaints from Space

One of the most common medical complaints is the loss of muscle. Due to the lack of gravity, muscles don’t require the necessary workload that it would do on Earth. This lack of resistance means muscles is lost when they’re not used. Even non-vigorous exercise on earth, such a slow stroll, requires more effort than the amount required on the ISS. Floating around the space station means that astronauts only need a simple touch of their hands or feet to move in the opposite direction.

Another complaint is the loss of bone mineral density (BMD). Astronauts BMD dipped 14% during their 6 month stays on the ISS, with 3 astronauts losing nearly 30 percent. While it may not sound too dramatic, it does put astronauts at a greater risk of age-related fractures, such as hip fractures and increased-likelihood of fractures as the consequence of an accident.

There are also numerous different medical conditions that doctors are only beginning to understand and treat, such as chronic back pain in astronauts once they returned to Earth.

There are also a number of less-serious issues microgravity issues that exercise will help prevent. One of these is fluid shift in space. Since gravity is no longer pulling your bodily fluids towards the ground, this causes issues to an astronaut’s circulatory system and even vision impairment. However, these are normally returned to normal once back on Earth.

The Gym

At 408km above us, those astronauts are probably doing a run or lifting weights at this moment in time. However, their gym is probably a lot more sophisticated than yours.

The equipment has been adapted for space- a stationary bike, a treadmill and a weightlifting machine. Because the astronauts don’t have gravity to work against, the machines have been specially designed for the weightlessness of space. The stationary bike doesn’t have a seat (why do you need a seat if you’re floating?), the treadmills have bungee cords so the runner doesn’t float away and the weights have canisters that create vacuums so they add resistance.

The astronauts spend a large chunk of their time at the gym – up to 150 minutes per day. It is vital that all the muscles get a workout to avoid muscle loss.

What Does This Mean for Future Space Travel?

Humans are still in their infancy of space travel and there are still so many unknowns when it comes to how the fragile body would react to long-term exposure of the indifference of space.

There have been many studies saying that muscle degradation over long spaceflights, such as one to Mars, may render the astronauts medically incapable to carry out their duties due to chronic back pain. Since we know the causes of this (microgravity and lack of opportunities to maintain muscle), we can adapt our vessels to accommodate these needs. These could include the creation of artificial gravity through inertial force and through mandatory gym usage.

Many other medical issues will need to be addressed before humans can venture out towards the stars. Once the ISS is decommissioned and the next space station is created, there will be a greater emphasis on the gym area and possibly an area with artificial gravity through inertial force.

Do you think that humans can, one day, live for long periods of time in space without medical consequence? Let us know on Facebook, Twitter and LinkedIn.

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