Walking on Air: NASA's Floating Treadmill
From: NASA News - 01/04/2006

A team of engineers at NASA's Glenn Research Center and The Cleveland Clinic
Foundation has developed a new treadmill that simulates the space
environment. The information gathered will help NASA design better exercise
equipment for use by astronauts in space, and also could help doctors treat
and prevent osteoporosis here on Earth. 

The treadmill is based on the Zero Gravity Locomotion Simulator (ZLS), a
machine mounted vertically in a free-standing frame that supports a runner
under the head, torso, arms, and legs - similar to running in place on a
wall. NASA added four air bearings to the device to make it float - like an
air hockey table. This enhanced ZLS (eZLS) will be tested on humans this
spring. 

Read the entire article at:
http://www.nasa.gov/mission_pages/station/science/eZLS_treadmill_010306.html