Work out in artificial gravity can protect astronauts

A combination of exercise and artificial gravity may significantly lessen the negative effects of extended weightlessness in space on astronauts, MIT scientists say.
Astronauts on the International Space Station (ISS) have a number of exercise options.
They spend a significant portion of each day working out to ward off the long-term effects of weightlessness, but many still suffer bone loss, muscle atrophy, and issues with balance and their cardiovascular systems.
Now engineers at Massachusetts Institute of Technology (MIT) have built a compact human centrifuge with an exercise component: a cycle ergometer that a person can pedal as the centrifuge spins.

The centrifuge was sized to just fit inside a module of the ISS.
Human centrifuges are spinning platforms that, at high speeds, generate forces strong enough to mimic gravity. An astronaut, riding in a centrifuge, would presumably feel gravity's reinforcing effects.

After testing the setup on healthy participants, the team found the combination of exercise and artificial gravity could significantly lessen the effects of extended weightlessness in space - more so than exercise alone.
Laurence Young, the Apollo Programme Professor in MIT's Department of Aeronautics and Astronautics, said artificial gravity would be a huge benefit for astronauts, particularly those embarking on long-duration space missions, such as a journey to Mars.

"With exploration-class missions, like Mars, where you're gone for three years, you could run the risk of having astronauts not sufficiently conditioned to perform effectively, and also to not be in good health when they finally get to the surface of Mars," said Young.
Young said a human centrifuge aboard a Mars-bound spacecraft would help keep an astronaut in shape over the many months it would take to get to the red planet.
The team's compact centrifuge resembles a rotating metal cage with three main elements: a chair; a cycle ergometer, or the mechanical portion of a stationary bicycle; and a suite of sensors to measure cardiovascular variables such as blood pressure, heart rate, respiration rate, muscle activity and foot forces.

Researchers conducted experiments to test human responses and exercise performance at varying levels of artificial gravity.
The experiments involved 12 healthy subjects, who participated in three sessions, each consisting of a bicycling workout under one of three artificial gravity levels.
During each session, participants were asked to pedal for 15 minutes at three workout intensities, or levels of resistance, set by the cycle ergometer.
The remaining 10 minutes involved spinning up and slowing down the centrifuge.
The participants tolerated the experiments well, suffering little motion sickness even while spinning at relatively high velocities.
The results were published in the journal Acta Astronautica.