At the height of training, he'll bike, run and swim 30 hours a week. He'll juggle his workout schedule with his full-time job and family responsibilities.
His wife, Beckie, on the other hand, does not like to work out. To her, exercise is a "necessary evil."
The Conways, of Shoreview, Minn., make room for fitness even though they're on opposite ends of the workout spectrum. Over the years, they've figured out ways to accommodate each other and keep the peace.
Their biggest lesson: Communication is good. Nagging is not.
Professionals tend to agree with them.
"It's about making sure you're clear with each other," says Tim Hatfield, professor of counselor education and a stress management instructor at Winona State University.
Graeme Attwood, director of operations at the SweatShop in St. Paul, Minn., sees differences in couples depending on their age.
Younger couples often start working out together with gusto. Over time, one sticks with it, while the other drops out. Older couples, meanwhile, already seem to know what each will or will not do. Attwood often sees wives who choose to work out with female friends instead of with their husbands.
Women typically exercise for health and overall fitness. Men, on the other hand, often train with specific sports goals in mind, Attwood says.
That's the case with the Conways.
The couple's negotiations actually began a decade ago. Their kids were 12 and 9. Both parents decided the children had to be the top priority. A former marathoner, Dan Conway stuck to four to five local triathlons a year. He worked his training around the family schedule, getting up at 4:30 in the morning to fit it in. At times, he's tried to get his wife excited about exercise, but she just isn't interested.
Gyms hold no appeal for her.
"He's tried, but it ain't going to work," Beckie Conway says. "He knows it. I know it. That is something we're not going to do together. But it's not like we don't share other things."
Five years ago, the Conways returned to the negotiating table. Dan Conway had started eyeing Ironman. At the same time, Beckie Conway wanted to return to graduate school.
"We had a heart-to-heart," Beckie Conway says. "(He said) 'If you go to school, will you support me when I do this?'" She agreed.
Beckie Conway eventually got her master's degree in organizational leadership from Bethel College. Then it was Dan Conway's turn. He began his march toward Ironman. A year ago, he hired a coach and started training for Ironman Florida. He cranked up his workouts last summer. Beckie Conway came face-to-face with the promise she'd made years earlier.
"It was more than I bargained for," Beckie Conway says. "I told myself, 'You said you would support him on this.'"
She learned to be patient. So long as the dogs get a walk and the sidewalks are shoveled, she doesn't mind if home-improvement projects go unfinished.
They worked out a good system of communication: a schedule board on the refrigerator. Dan Conway doesn't train Wednesday nights so that's when they plan shopping trips or movie outings.
Conway completed Ironman Florida in 11:45. This year, he's planning to do Ironman California and Ironman Canada (if necessary) to qualify for Ironman Hawaii in October.
"A lot of people have second full-time jobs," Beckie Conway says. "This is just like he has another full-time job."
Dan Conway says the key is flexibility. He picks races early in the season. If he has to miss a day of biking, so be it. He's planning to do one or two more Ironmans and move on.
"This one is a life goal," Dan Conway says. "Beckie's in tune to that. But she's not going to do this forever. She has her limits."
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