The racers sat or lay practically on the ground, their arms pushing the pedals in front of them, propelling them forward.
As spectators cheered, clapped and rang cowbells in support, the riders just continued to push themselves, determination and fatigue showing on their faces.
"I don't know how they do it," said Paul Betz, a cycling enthusiast from Columbia, Tenn. "I think their strength and upper-body endurance -- they must have big engines to be able to go as fast as they do, and be as competitive as they are. It's impressive."
U.S. Paralympics is continuing a partnership that began in 2010 in Greenville, S.C., with USA Cycling, when handcycling was included in the national pro championships. This is the race's second year in Chattanooga.
"I think it's a great course. Chattanooga seems to have really been very courteous to the event and done a great job hosting it," Betz said.
About 35 handcyclists raced on a one-mile loop for 30 minutes, which ended on the winner's final lap.
Judges average racers' lap times to help determine the winner. Once they have an average lap time, they can figure out when the final laps are coming up and then determine who the winner is.
The riders today were competing for qualifying points to take part in the 2016 Paralympic Games and the 2014 Paracycling World Championships, which take place Aug. 28-Sept. 1 in Greenville.
The overall criterium winner was Alfredo De Los Santos with the Paralyzed Veterans of America racing team.
David Randall, 40, with Team Roger C. Peace, who was the overall criterium winner in 2013, took first in the Men's H3 category Monday.
William Groulx and Carlos Moleda of Paralyzed Veterans won in the Men's H2 and H4 categories, respectively. Marianna Davis, with U.S. Paralympic, took first place in the Women's H3 category; Rosa Thea, with Victory Velo Racing, won in Women's H4; Oksana Masters from Illinois won in Women's H5.
Randall, who played basketball and soccer in high school, got his start handcycling after discovering in 2001 that he had a rare genetic disease known as von Hippel-Lindau disease, which causes tumors in the brain and spinal cord. He said he's had four back surgeries and three brain surgeries as a result.
Randall said he took up handcycling in 2005 as a way to get into shape, and when he went to a developmental camp at the U.S. Paralympic Training Center in December of 2008, he impressed the coaches and joined the national team in 2009.
"I was an athletic guy before the injury, and honestly after my injury I was a little depressed," Randall said. "I went into about a six-month kind of thing and then found out about handcycling.
"It gives you something to live for, and just come out and focus on. And then getting to travel the world with the Paralympic Team -- it's given me the opportunity to do a lot of things that I probably wouldn't have done as able-bodied."
Contact Alex Harris at firstname.lastname@example.org or 423-757-6592.