NASA has developed a new pair of sandals called ForceShoe to help astronauts exercise in space.

The brown strap-on shoes are being worn by astronauts from the U.S., Russia and Germany, according to Sky News.

The footwear will be placed on top of small monitoring devices that will send data back to control centers on Earth.

In addition to ForceShoe, the space agency has developed the exercise machine Advanced Resistive Exercise Device (ARED) to help astronauts stay in shape on long-term missions on the International Space Station (ISS), CNET reported.

The shoes, designed by 3D motion-tracking technology company Xsens, features motion trackers and force sensors.

The astronauts will wear ForceShoe when they use ARED. The shoes will help scientists achieve a better understanding of the forces put on the astronauts' bodies, Sky News reported.

"Crew members will be asked to set the ARED to provide specific loads in the same way they would set loads on a weightlifting machine at the gym," NASA said. "They will then lift the exercise bar and stand still on ARED while the shoes collect data."

The space explorers will perform exercises such as squats, weightlifting and bicep curls. The collected data will be used to build exercise programs on the ISS, CNET reported.

"We are eager to understand how joint forces may be different between exercise performed on the ground and in space, and force-shoe technology might help us do this in future investigations," said Andrea Hanson, exercise hardware specialist for ISS.

The data could also help train astronauts to be in shape for exploring rough terrain on Mars or asteroids.

ForceShoe was worn by Russian cosmonaut Maxim Surayev, his colleague Reid Wiseman from NASA, and Alexander Gerst from the European Space Agency, who docked with the ISS on Thursday, Sky News reported.

The astronauts, along with others from the U.S. and Russia, will carry out a 167-day mission on the Soyuz spacecraft. They will return to Earth in November.