Team Cleveland re-imagines muscle stimulation technology to defend world title
It is hard to beat making history, but both the Cybathlon 2020 Global Edition and the United States’ Team Cleveland (Ohio) are betting on advances in adaptive bicycles to do just that this weekend.
Specifically, Cleveland hopes to repeat its 2016 win in the virtual functional electrical stimulation bike races, which will stream online as one event on Friday, Nov. 12.
Ronald J. Triolo, Ph.D., Cleveland engineer and professor of orthopedics and biomedical engineering at Case Western Reserve University, is the team manager.
Four years ago in Zurich, Switzerland, he was yellow-carded for jumping onto the track to congratulate backup pilot Mark Muhn on securing the gold medal for the United States. Muhn suited up after team lead pilot Michael McClellan was disqualified, and he beat 11 competitors with a time of 2 minutes, 58 seconds over the 750-meter course.
This year, that distance increases to 1,200 meters, with a maximum time of 8 minutes allowed. And instead of competing inside a stadium full of fans abroad, the team will film inside the atrium of the Administration Building at the Louis Stokes Cleveland Department of Veterans Affairs (VA) Medical Center, where Triolo first met Muhn.
In 2012, Muhn volunteered to participate in a research study in which he received an implanted stimulation system to help him stand and to stay fit, after a ski accident in 2008 left him paralyzed from the chest down.
All paraplegic and tetraplegic pilots competing in the Cybathlon previously rode recumbent bikes powered by their own muscles. This year, on their own turf, competitors will pace time and distance on a standard stationary bike trainer.
Muhn is confident about repeating his win, despite limitations the novel coronavirus (COVID-19) pandemic introduced to his training, as well as ribbing from his international rivals.
“There’s always the intimidation because there are so many factors that have to work correctly,” Muhn says. “Once I’m 30 seconds into the race, though, those fears dissipate, and I concentrate on what I know how to do. I’m only racing against myself at that point.”
According to Triolo, the basic physiology of a spinal-cord injury is challenging even before adding gadgets to the game plan. Muhn broke his neck at the C7 vertebra. Now, at the push of a button, his high thoracic injured area responds to electrical signals that excite live nerves and send pulses into 24 muscles in his legs.
“Physiologically, if we can get those muscles to contract as hard as we want them to, we can build strength and endurance. But after spinal-cord injury, the heart rate response lags, so it’s harder to get a high intensity interval workout,” Triolo says.
In the race, pilots control the power supplied to their muscles and regulate their speed. The only external item Muhn carries onboard is the transmitter on his abdomen.
“Mark has had some ups and downs, and we had some issues with his system after the first race. Now, he is all tuned up. He wanted to defend his title and pushed us to do better,” Triolo says.
Triolo also says people with higher injuries, like Muhn, have less control over their breathing, which is a big deal.
“We have to remind them to breathe, so that they can get oxygen to the muscles and keep pumping, because that disconnect with the heart rate could cause them to fall asleep while they are pedaling the bike,” Triolo says.
Muhn says he’s quite comfortable with the implanted system.
“It is part of me now, just like having a foot or hand,” he says.
In the weeks leading up to the competition, as organizers pivoted from plans for live footage to a prerecorded feed, the team at Case Western ran trials to learn how to communicate with Switzerland using new, computerized data.
Muhn, who trains at home but travels to Cleveland from California four times per year, says his only job is, “making sure that I stay healthy and I do the right thing on race day.” He says riding the stationary bike without any scenery going by can sometimes feel like a chore.
“But when I finish up, my spasticity has left my body, and that is satisfying,” Muhn says.
Team captain and physical therapist Lisa Lombardo says Muhn has always been capable and has good endurance.
“Now it’s about maximizing his speed over that distance,” she says. “We’re onto something. Mark was a rabbit with a big burst of energy. Now, we are changing that to keep a slow, steady pace throughout the whole 1,200 meters.”
In 2016, the team suggested adding a sprint and a marathon-style event because the longer the better for Muhn, but he acknowledged how hard it is to level the virtual playing field.
“I still have shifting capabilities, and it’s really all about that,” Muhn says. “Feeling the cadence and making the most out of what power I do have. Brakes are overrated.”
Muhn says there are sometimes more questions at the end of his training day than at the beginning, but that is what this research is about.
Robert Riener, Cybathlon founder and professor at ETH Zurich public university, says the main goal of the competition is to raise awareness of the challenges people with disabilities face and find the best ways to connect humans and machines for a user-friendly future.
The 2016 Cybathlon marked over a year-and-a-half of work by 20 people for Triolo’s team.
“There is an ebb and flow of attention and excitement driven by the bikers,” Triolo says. “There is no one answer, but after the first competition, we asked how to make the benefit Mark is getting more widely available.”
With that goal in mind, Triolo secured more funding from the Craig H. Neilsen Foundation to develop a tablet-driven program that a clinician can use without engineering support.
“More people are going to be able to use the surface stimulation than receive implants,” he says. “Plus, it lets people tune the values to their own specifications.”
Through the VA Innovators Network, Triolo is starting trials at the Pittsburgh VA Medical Center in Pittsburgh, and the James J. Peters VA Medical Center in the Bronx, N.Y., and has developed a test for a local adaptive gym called Buckeye Wellness.
The renewed focus on exercise itself and role of physical therapists brought exercise physiologist John McDaniel from Kent State University in Ohio to the team, which is where the first surface stimulator bike was sent. McDaniel also had planned to enter his competitor prior to COVID-19.
It’s not just about testing — it’s fun.
“Mark is exceptional, but none of us can feel what he is going through. It’s also hard to do something healthy unless you enjoy it,” Triolo says. “That is the magic of biking. There is a competitive streak in all of us, so we want to convince more people to pursue implant technology with a different, creative approach that will accelerate progress.”
Standing at the starting line is hard to recreate, but Triolo says what he will miss the most is being surrounded by pilots like Muhn.
“You are not going to get the same adrenaline rush as when you’re passing somebody on a track, but we think if Mark can beat his personal best, he’s going to have a good chance of beating almost everyone else,” Triolo says.
Added Muhn: “The only views my competition will have is the same as last time, and that is the back of my head as I lap them to the finish line. I might go home exhausted, but I’ll leave nothing behind.”
Cycling coverage starts at 6 p.m. Central European Time, (12 p.m EST) viewed at: https://cybathlon.ethz.ch/en/event.