[1] StairMaster was founded by Lanny Potts, Jim Walker, and George Schupp and launched by Tri-Tech, Inc. of Tulsa, Oklahoma in 1983 at the National Sporting Goods Association trade show.
In 1991 StairMaster Exercise Systems, sued Temecula, California based Tru-Trac Therapy Products Inc. who made the "Aero-Step" alleging that their 1987 patent was infringed upon.
[3][4] As of 1989, the StairMaster 4000 was the company's most popular model, which Aron Kahn of the Ottawa Citizen attributed to its affordability and implementation of positive reinforcement through an on-screen display of goals and congratulatory messages.
It quickly became popular among gym-goers, although Karen Avenso of New York Daily News noted that it "[looked] more intimidating - and harder to program - than a VCR.
The article went on to state that the Ecofit Company compiled data from 967 fitness centers and determined that Stepmills were being used 18 times as often as Stairmasters.