OYO Fitness founder Paul Francis has been inducted into the Space Technology Hall of Fame for inventing SpiraFlex resistance technology and producing NASA’s first resistive exercise devices. SpiraFlex has been spun off to power the Bowflex Revolution Home Gym and the OYO Personal Gym.

Long stays in space, such as on the ISS, take a toll on the human body, as muscles atrophy and bones weaken and lose minerals. Astronauts have long used exercise equipment to help mitigate the effects of microgravity on their bodies. But as NASA astronaut Shannon Lucid found in 1996 after a six-month stay on the Mir space station, the station’s stationary bike and treadmill were insufficient to prevent muscle and bone loss. A resistive exercise device was needed. The challenge was that the best solution on Earth was weight training but that required gravity.

Before the first crew arrived on the ISS, NASA required a more effective countermeasure for muscular-skeletal degradation. At that time, Dr. Roger Billica was the chief of the Medical Operations Branch at NASA Johnson. Muscle-strengthening using resistive exercise equipment seemed to be the best solution.

Dr. Billica put out a request for design ideas to meet the needs of exercise in zero-gravity. Many design ideas were submitted, both from outside companies and from within NASA. Dr. Billica put together a solutions team to evaluate the proposed designs.

One of the submissions came from Paul Francis. His idea was to use a rubber elastomer wound into disks called FlexPacks. The concept later branded SpiraFlex, provided a linear resistance that could be used on a custom-designed exercise machine that simulated working with free weights. Working with NASA Johnson Space Center’s Life Sciences and engineering teams, SpiraFlex Inc. created the Interim Resistive Exercise Device (iRED).  NASA physiologist Michael Rapley was instrumental in the IRED’s development and its deployment to the ISS. Mike helped collaborate efforts between Paul’s hardware design and NASA’s engineering and Life Sciences teams.

Using their patented SpiraFlex technology of molded elastomeric spiral disks. Once connected to a spiral pulley, the discs provided linear resistance up to 300 lbs. While on-orbit, crew members could complete daily exercise protocols, including squats to load the spine, hips, and legs, which are most affected by microgravity.

A NASA sponsored 16-week study showed that the SpiraFlex iRED provided comparable results to using free-weights. iRED was the first resistive exercise system built specifically for space. It was installed on the ISS in 2000 with the first long-duration crew. It proved so effective it was used on the station until 2009 when the vibration isolated Advanced Resistive Exercise Device (ARED) was ready.

The patent owner, Paul Francis, assigned his patents to SpiraFlex Inc., which in turn licensed the technology to Nautilus Inc., who has since developed and markets their Bowflex Revolution home gym, and to OYO Fitness LLC. Today OYO Fitness has developed and markets OYO Personal Gym for individual use. The primary advantage of using SpiraFlex technology on Earth is that users can obtain the same benefits of weight training without the need for heavy cumbersome weights and related equipment.

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