Science  /  Origin Story

The History of the StairMaster

The 1980s brought about America's gym obsession—and a machine that demands a notoriously grueling cardio workout

By 1983, Potts, Walker and Schupp had founded a company called Tri-Tech and were ready to launch their first product. Originally dubbed the Ergometer 6000, the stepper was renamed the StairMaster 5000 by then-marketing director Ralph Cissne. The machine debuted at the National Sporting Goods Association (NSGA) trade show in Chicago, to attendees who worked in the country’s growing sporting goods industry. These potential buyers would have primarily worked in retail or wholesale—the first links in a long chain that would end in neighborhood gyms.

The following years brought new iterations. In March 1984, Tri-Tech released the StairMaster 6000—essentially the same design, but with the addition of a digital screen. Early advertisements for the StairMaster 6000, still bearing a “patent pending” disclaimer, emphasized the new machine’s digital benefits, such as readouts that showed the calories burned and audio tones that would ring when users climbed a virtual flight of stairs.

The company’s next chapter began with a patent application Potts filed in August 1986, describing a new machine called the StairMaster 4000 PT (short for Personal Trainer). This version replaced the machine’s escalator-like stairs (which made it, technically, a stepmill) for a pair of pedals that “simulate stair-climbing for a user.” Instead of climbing the rotating flight of stairs, StairMaster 4000 PT users could set the resistance level, then “climb” the pedals as if standing while pedaling a bike.

The StairMaster’s innovation lay in the stairs themselves: it was possible to adjust the height of the stairs individually. Instead of a one-size-fits-all approach, users could climb stairs spaced according to their height. The design even allowed users to safely set two different increments—a helpful feature for anyone whose stride isn’t perfectly even. Two days before Thanksgiving in 1987, the StairMaster 4000 PT’s patent was granted.

Tri-Tech’s decision to manufacture exercise equipment was far from random. In fact, Walker and Schupp’s decision to pivot to fitness was perfectly timed. Fitness “absolutely explode[d]” during the 1980s, according to Natalia Mehlman-Petrzela, a professor of history at the New School in New York City who is currently writing a book about the history of fitness culture. “Gym culture evolved from being a very strange subculture as late as the 1950s and even 1960s to being the ubiquitous cultural phenomenon that we see today,” says Mehlman-Petrzela. Though some people purchased StairMasters for personal use—particularly the 4000 PT, which was sleeker—the StairMaster’s rise to fame was inextricably intertwined with the boom in gyms and fitness clubs.