Did you know that on an average astronauts lose about 1 to 1.5 percent of bone mass in a single month! That is the exact percentage lost by postmenopausal women if left untreated for bone loss in one whole year. And the major reason why bone loss in space is so common is because there is hardly any gravity acting on the body. On the ground, your body works 24/7 against gravity to just stay upright and then add to that exercise, walking, jumping and every single activity one does. Up in space, none of these activities actually need much effort. So, how do astronauts ensure against rapid bone loss and muscle degeneration? Do they read up some treadmill reviews and get themselves one of the commercial variants?
Take the ISS or International Space Station, it has some pretty fancy equipment and they even game them names! The treadmill is called COLBERT, the stationary bike is named CEVIS and then a unique weightlifting simulation device is called ARED.
The treadmill isn’t what you would find in the market. It is specialized to work in microgravity. Understand that on earth, gravity allows us to stay rooted to the ground and thus walk, jog or run on a treadmill. However, up there where gravity’s effect is negligent, nothing will keep the astronaut rooted to the treadmill belt. It is for this reason the COLBERT actually requires one to be harnessed to place.
You probably thought that up in space, running was like you see in the movies with a slow revolving tube to simulate some amount of gravity and a conventional treadmill like a Precor 9.23 treadmill rooted to one side. Reality is that simulating gravity to an extent where regular exercise like on earth becomes possible is not yet feasible. Until then the COLBERT will undergo many more iterations.