Television sports analyst Skip Bayless probably burns more calories during “First Take” than most people burn in a CrossFit class.

The ESPN morning talk show, taped live five days a week, features two hours of unscripted debate. “When I walk off the set, you could wring out my T-shirt and the top of my underwear. I’m sopping with sweat,” Mr. Bayless, 63, says. Known for relentlessly defending his opinions on the show, he admits he likes to be right. “I want to win every debate and I think I do,” he says.

Mr. Bayless says he is convinced his fitness level helps him stay sharp throughout the show. “Live TV is physically grueling,” he says. “I’m concentrating very hard to recall numbers, dates and events to bolster my argument and win a debate. Every eight to 10 minutes, a new sport or topic is thrown at me.”

Mr. Bayless is just as relentless when it comes to his workout routine. He does an hour of cardio every morning, and lifts weights three days a week after his show. He has missed only two days of cardio since April 1998—because of a sinus infection in 1998 and a bout of hepatitis A after eating bad sushi in 2009. He has had three arthroscopic surgeries on his knees and, much to his surgeon’s dismay, was riding the stationary bike as soon as he was home from the hospital.

“My colleagues think I’m crazy but my motto is, never miss a day,” he says. “If we’re taping in L.A., I’ll get up at 2 a.m. to go run. If I’m on the road and the hotel doesn’t have a gym, I’ll find a 24-hour gym,” he says. “I don’t know how to exist without my workouts.”