Barry Plaga never imagined that slowing down could improve his performance.

Before the pandemic, Mr. Plaga, chief financial officer of a cybersecurity company, averaged two Ironman races, three half-Ironman races and a handful of half-marathons throughout the year. When the pandemic canceled competitions, his four-hour runs and six-hour bike rides no longer served a purpose. Pool closures paused his weekly swims.

He...

Barry Plaga never imagined that slowing down could improve his performance.

Before the pandemic, Mr. Plaga, chief financial officer of a cybersecurity company, averaged two Ironman races, three half-Ironman races and a handful of half-marathons throughout the year. When the pandemic canceled competitions, his four-hour runs and six-hour bike rides no longer served a purpose. Pool closures paused his weekly swims.

Mr. Plaga completed the 2019 Ironman World Championship in Hawaii.

Photo: Finisher Pix

He and his wife, also an endurance athlete, decided to shift their workout goals. They would aim for “getting their butts out of their home office chairs” to work out at least one hour per day, says Mr. Plaga.

The average exerciser would still consider those workouts intense: up to 400 squats and 100 push-ups in a session. Yet scaling back long-distance cardio training allowed him to rest not just his body, but also his performance-focused mind.

When Mr. Plaga, 59 years old, started training again this spring, he was shocked to see his times improved.

“I’m running faster than I was pre-Covid,” says Mr. Plaga. Before the pandemic hit, he realized, “I was clearly overtraining.”

He has introduced more variety in his training now and has scaled back his race schedule. He’s currently preparing to run the Grand Canyon rim-to-rim-to-rim, an out-and-back crossing. His 2022 race schedule includes a half-Ironman in Oregon in July and a 50K trail-running race in September.

Stretching has become essential with age, says Mr. Plaga.

The Workout

Mr. Plaga splits his time between Bellevue, Wash., and Big Sky, Mont. He uses his Montana home for altitude training. He builds his weekly running mileage from 25 miles to 45 miles over eight weeks, he says. In addition, he throws in three one-hour, high-intensity indoor rides on his trainer, a device that attaches to a bike so you can ride in place indoors, and one long swim of around 3 miles at 4,000 feet elevation, per week.

He does twice-weekly strength sessions that include core exercises performed on a TRX suspension trainer, five one-minute plank holds, four sets of 100 squats, four sets of 25 push-ups, and four sets of 15 supermans, an exercise performed by laying on his stomach and lifting his arms and legs simultaneously off the ground.

“As I’ve gotten older, stretching and strength training, particularly core work, have become increasingly important,” he says.

At the peak of triathlon training, about six to eight weeks from race day, he’ll do four 3,000- to 4,000-meter swim sessions a week, four bike workouts ranging from 75 minutes indoors to six hours outdoors, and four runs including hill repeats, 30-minute post-bike runs. His wife, Johnna Plaga, is his go-to training partner.

“She keeps me accountable,” he says. “And in check. At my age, I need more hiking and walking at elevation, especially to prepare for the Grand Canyon.”

Mr. Plaga runs with his favorite training partner, his wife, Johnna Plaga.

To keep aches at bay, he gets a sports massage every two weeks and grits through 20 to 30 minutes of daily foam rolling.

The Diet

Pre-workout fuel: A banana and an almond-milk protein shake spiked with maca root powder and cacao.

Breakfast: Greek yogurt with honey or two hard-boiled eggs.

Lunch: A turkey or chicken sandwich. “I try to stick to whole wheat bread but if I ordered from a place with great sourdough I make an exception,” he says.

Dinner: A salad topped with grilled steak is a staple. Once a week he and his wife cook pasta. During pandemic lockdown they made a pact not to order takeout and instead trade off cooking. “We each had to prepare at least one new homemade recipe each week,” he says. His white bean soup was a hit throughout winter.

Avoids: “Fried stuff puts me in a food coma,” he says.

Splurge: Hawaiian pizza and Mexican food. “I love carne asada soft tacos and chile rellenos, and of course a margarita,” says Mr. Plaga.

The Plagas are both endurance athletes.

Essential Gear

For Cycling: Quintana Roo PRsix Disc triathlon bike with electronic shifting ($9,600), Shimano SH-TR9 cycling shoes ($275), Smith bike helmet ($200), Garmin Edge 1000 bike computer ($500)

For Swimming: ROKA Maverick Pro II wetsuit ($750), ROKA R1 swim goggles ($38)

For Running: HOKA One One Bondi 7 sneakers ($150), Garmin Forerunner 935 watch ($500), Birddogs shorts ($60-$65)

Playlist

“I’m a rock person,” he says. “I like something fast-moving from artists like the Foo Fighters, Pop Evil and Avril Lavigne. If the music slows down, I seem to slow down.”

Are You Overtraining?

When you’re training at a high level, recovery and rest are important, says Jimmy Prendergast, associate director of athletics for sports performance at Hofstra University in Hempstead, N.Y.

“In addition to the physical stress, there is a lot of mental stress that comes with fitting in workouts and hitting times,” he says.

Mr. Prendergast notes that ahead of a competition, training should be lighter to allow the body to recover. “Do the movements but at a relaxed pace,” he says. Signs that you may need a break or to scale back include fatigue, poor sleep, continued poor performances at practices or workout and mental stress over performance.

“When you’re burning the candle at both ends you burn out and that’s when injuries happen,” he says. “Training is structured and can become monotonous. Add in activities you look forward to so you can stay motivated and enjoy the lighter training days.”

What’s your workout? Tell us at workout@wsj.com.

Write to Jen Murphy at workout@wsj.com