Marianne and Paul Larson work out together four times a week, often enough in sync that they can plan dinner at the same time.

Try waking up next to your training partner.

Some couples have found that exercising together can yield benefits far beyond just getting in that day's workout, as I learned recently when talking with three couples who train together at Bellevue's Pro Sports Club.

Though Marianne Larson, 57, of Redmond had been running and doing water exercise three to four times a week, her husband Paul, a researcher at Microsoft, "wasn't into working out at all," she says. After seeing couples exercising together, she talked him into giving it a try. They started out on their own but soon realized they needed more focus and guidance, and hooked up with trainer Buzz Aagaard.

Two years later, Paul, 55, who likes hiking and sailing but had never followed a regular fitness program, has lost 35 pounds. Marianne, a retired nurse, has been pleasantly surprised by the relatively quick changes she saw from her first foray into weight training. Together, they've run a 10K.

"Some things we do together and some things we do separately, but I think the main thing is it's fun to do it together," Marianne says. "You'll have a morning when you don't really feel like going, and then you don't want to disappoint your partner, so you go anyway. There's that little bit of competitiveness — 'He's losing weight, why am I not losing weight?' or 'If he's doing 40 minutes on the treadmill, I can, too.' And then there's the encouragement. It's really added a new aspect to our life."

Fitness news you can use A treadmill story Biologists at the University of Utah trained five young Florida alligators to walk on a treadmill in a study that yielded new clues about how dinosaurs breathed. Unlike lizards, alligators are able to walk and breathe at the same time because of a rocking pubic bone that helps them inhale and exhale. The study suggests a similar mechanism might have enabled dinosaurs' endurance and active lifestyles. It took several months of training before the alligators, who were up to three feet long, could walk on a treadmill 1 mph for three to four continuous minutes. They wore masks so researchers could measure oxygen consumed, carbon dioxide exhaled and the depth of each breath. Monitors were attached to determine muscles used and abdominal pressure. A note in the press release about the study: "Due to the sensitivity of the alligators, they will not be available for photography or videotaping."

They stopped the personal-training sessions last summer when their emphasis shifted toward sailing. But they've continued their joint workouts, four times a week.

"I think the most important part," Paul says, "is if you're doing it together, it's harder to come up with excuses not to go."

Cindy and John Larson (no relation to Marianne and Paul) of Issaquah, are in their early 50s and both retired, she as an architect and he as a construction engineer. "We needed to lose weight and get in shape," says Cindy, so a year ago they started working with Carol Taylor.

"Both of us were pretty much of the opinion that if we were gonna do it, we'd have to do it together, because goodness knows we'd failed enough on our own." Though they had to negotiate when to work out — since her optimum workout time was early morning and his was later, they compromised at mid-morning — training together and changing their eating habits have definitely worked: Cindy has lost 60 pounds and John closer to 80, and they're aiming to drop another 35 each.

Trina and Dean Kain of Kirkland, managers at Microsoft (she finance, he business), linked up with Carl Swedberg.

"We're not necessarily on a big weight-loss kick," says Trina, 39. "We're just trying to increase strength, get firm and feel good — because it feels good to work out." She's noticed improved strength in her upper arms and body, and Dean's workouts keep his back problems at bay.

"There's a level of respect," says Dean, 40, "that encourages you to show up" — and also good-natured chiding if the other misses a session. "Having someone you know and care for there allows you to add a little bit of extra effort and encourage your partner to succeed. It's a teamwork type of atmosphere, all for the common goal."

Although plenty of couples bicycle, ski, play soccer or find other perhaps less costly ways to exercise together, the expense of personal training can also have its benefits.

"Having a trainer is just a great idea," Trina says, "because you pay whether you go or not."

"We're investing in our future," Dean adds, who's aware that's even more true now that Trina is pregnant. "That's the justification for the cost."

Molly Martin is assistant editor of Pacific Northwest magazine. Mike Siegel is a Seattle Times photographer.

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