But theyre not just sitting. As NASA astronaut Jessica Meir explained in a , living in microgravity means that crew members on the ISS would lose bone density and see their muscles atrophy if they didnt work out. Staying fit in space offers its own unique challengestheres the isolation, of course, but the astronauts also cant just take the dog for a walk whenever they need a breath of fresh air.
Meir demonstrates three machines astronauts use to exercise. The first is the Advanced Resistive Exercise Device (ARED), which she describes as a one-stop weightlifting machine. It looks similar to something youd see in a gym, but adapted for space: Rather than using weights and gravity to provide resistance, it uses a pair of vacuum tubes. The astronauts can do squats, lifts, pressespretty much anything youd do with a gym machine.
As the current residents of @Space_Station , @AstroDrewMorgan and I thought wed share some of our strategies for living happily in isolation. Tip #1: Exercise is vital not only for physical health, but also to your mental well-being. Heres how we do it on @Space_Station . . . pic.twitter.com/Dzyh5WYBBj Jessica Meir (@Astro_Jessica)
Thats great for maintaining muscle, but as you might imagine, cardio in space comes with its own challenges. Spacewalks arent enough to keep your heart rate elevated. So the ISS includes the aptly named T2, which just stands for Treadmill 2. It looks like a regular treadmill, but with bungee cords and a harness. That keeps the astronauts from floating away in microgravity; Meir says, Its pretty fun to run on T2. You get a little extra spring in your step.
Finally, for more cardio, the astronauts have a stationary bicyclethough in true NASA fashion, its called the Cycle Ergometer with Vibration Isolation and Stabilization (CEVIS).
Its got the pedals of a typical bike, but in microgravity it doesnt need a seat or handlebars. Astronauts use a pair of handholds to stay in position. Drew Morgan, another NASA astronaut, says,
I get a much greater heart rate doing this than I do running on the treadmill.
Most of us will never have to stay fit in the cold depths of space. But its good to know even astronauts have to work outand inspiration for those of use back on Earth.