Search Johnson



Text Size

William P. Jeffs
Johnson Space Center, Houston

John Koloen
University of Texas Medical Branch (UTMB) at Galveston

RELEASE : J08-001
New Treadmill Imitates Running in Space in Galveston
HOUSTON – Galveston soon will have a spot where people can do their morning run lying down, thanks to a new NASA device housed at the University of Texas Medical Branch.

The device, known as the Standalone Zero Gravity Locomotion Simulator (sZLS), imitates what it is like to exercise in weightlessness. Future generations of astronauts traveling to the moon or beyond will benefit from this device soon to be used in bed rest studies managed by NASA's Johnson Space Center.

The treadmill, built by a team of engineers at NASA's Glenn Research Center in Cleveland, was delivered to UTMB last year under the direction of the Johnson Space Center’s Exercise Countermeasures Project. The project will use the device to develop improved exercise routines for astronauts during spaceflight.

Living in weightlessness can lead to aerobic deconditioning, muscle atrophy and bone loss, all of which can affect an astronaut’s ability to perform. On the International Space Station, crew members exercise daily to help counter the effects of prolonged weightlessness. For astronauts’ health and mission success, this exercise is key to help lessen the harmful health effects of long-duration space travel, thereby ensuring astronauts’ best performance and overall well-being.

The sZLS will be used during future bed rest studies sponsored by NASA at UTMB. These test subjects experience similar physiological deconditioning during prolonged bed rest compared to what astronauts experience in space.

The bed rest studies, and use of the space treadmill simulation, will help researchers understand how to improve the exercise equipment used in space and astronauts' exercise regimens.

"These studies are a key component of our research into how we can better protect astronauts," said Linda Loerch, project manager for the Exercise Countermeasures Project at Johnson Space Center. "The focus of our work is to understand how to maintain astronaut's health and performance at the highest possible levels, both on our current flights aboard the station and for the future exploration beyond Earth orbit."

The sZLS is fashioned after an earlier version of the device developed in the 1980s at Penn State University. This team, now at Cleveland Clinic in Cleveland, collaborated closely with NASA in the development.

The Cleveland Clinic also conducts bed rest studies with a similar device for NASA. The devices all simulate zero gravity by suspending human test subjects horizontally and unloading the torso, head and limbs from the normal pull of gravity. The human test subjects walk or run against a ‘gravity-replacement load’ which pulls them toward the vertically mounted treadmill. The forces against a test subject’s feet are precisely controlled and can mimic conditions in space in zero gravity, or even on the moon, which has one-sixth the gravity of Earth.

In addition to simulating exercise protocols, the locomotion simulator may be used to mimic the physiological effects of extravehicular activity, or spacewalking. Future NASA studies using the sZLS will contribute to understanding how to improve exercise regimens for the astronaut to follow during spaceflight.

Video of the simulator will be available on NASA Television's Video File. For NASA TV downlink, schedule and streaming video information, visit:

Images of the simulator can be found at:

For more about NASA's plans to send humans to the moon and beyond, visit:

- end -

text-only version of this release