New app harnesses artificial intelligence to support fitness enthusiasts and coaches

Zihi promises to be “the world’s first adaptive and truly personalized training platform for runners.”
phone app that's in front of a face
Courtesy of Getty Images/Tim Burton

If the name Revere Greist — co-founder of the new fitness app Zihi — sounds familiar, it could be because of his contributions to the behavioral health tech scene in Madison. In 2007, he launched Waypoint Health Innovations, which designs computerized cognitive behavior therapy programs for people with mental illnesses. Ten years later he founded MERET Solutions with his father, whose name may also ring a bell: psychiatrist John Greist, co-founder of Epic Systems Corp. and a computerized medicine pioneer.

Or it could be that you like to ride your bicycle in and around Madison and you use the Strava fitness app, downloaded by 76 million. “Ah,” you’re thinking now, “that Revere Greist.”

Strava is a popular fitness app embraced by weekend warriors and elite athletes alike. Greist falls into the latter category — a Shorewood Hills native, he swam competitively for West High School and Wesleyan University before earning master’s degrees at the University of Chicago and UCLA, then raced bicycles for years. When his coach, Madison-based pro triathlete Patrick Brady, suggested he add running and attempt triathlons, he gave it a try — and placed fourth overall in Ironman Wisconsin in 2018. In 2019, he finished eighth in his age group in the Ironman World Championship in Hawaii and ninth in his age group in the Ironman 70.3 World Championship in France. Greist holds the No. 1 spot on numerous Strava “segments” around Madison. The app tracks data such as mileage, pace and routes, which you then share with followers (who offer thumbs-up “kudos” reactions). It can be motivating, whatever your level — and that’s not by accident, but by scientific design.

“I really did get into the Strava experience when it came out,” says Greist, who considers exercise foundational to mental health. “It was amazing to me that a digital platform could really change the way we behave in real life.” But Strava is just a tool, like TrainingPeaks (an electronic training diary with the option to purchase coach-designed plans), and both have their limits. Greist believes that working with a professional coach is still the gold standard, but it’s costly.

Then Greist met Egor Akimov, former head sports scientist for the Russian national triathlon team, now living in Middleton, and Mike Vinogradov, a world-renowned coach in the sport of orienteering. Turns out the men had an idea for a product that combined the best aspects of apps and coaching with artificial intelligence to create something entirely new. Greist immediately recognized its potential.

“It was amazing to me to see that you could develop a web-based program that would emulate what a cognitive behavioral therapist would do,” Greist says. The trio built a team, raised funds and, in June 2021, officially launched Zihi.

Zihi promises to be “the world’s first adaptive and truly personalized training platform for runners.” It harnesses artificial intelligence and machine learning to generate customized training plans, adapting after each workout based not only on objective data but also on subjective measures that other apps don’t track; it will eventually incorporate things like sleep, stress, muscle soreness, pregnancy, menstrual cycles and altitude changes. Greist says Zihi isn’t meant to replace coaches, but to support them. It will help reduce overtraining and prevent injury, and it could even have important crossover potential with Greist’s work at MERET, which is currently working on a suicide risk assessment project.

“When people start to get overtrained their symptoms present very similarly to how those who are depressed present,” Greist says. “We may eventually incorporate some of the standard psychometric measures into the subjective information people give us for Zihi.”

Until then, Greist will keep chasing segments while trying to keep up with his 82-year-old father, who wrote the 1977 book “Run to Reality” with Movin’ Shoes’ late co-founder, Roger Eischens. “He’s still an animal athlete. He rides to New Glarus on his bicycle at 19 miles an hour; I’m not kidding,” says Greist.

I hope that’s tracked somewhere.

Maggie Ginsberg is an associate editor of Madison Magazine.