Her Triathlon Goal: Guiding Others to the Finish Line

Ms. Gaynor learned to guide over a weekend. “A friend connected athletes with guides and he called me the week before the New York City triathlon asking if I knew of anyone who could help,” she says. “I volunteered, even though I had no experience. There is a reason tandem bikes are called divorce-makers. I thought I was going to crash, the bike was shaking so badly.”

Ms. Gaynor travels one to three times a month to meet with financial advisers as a regional director for Dimensional Fund Advisors, a global investment manager that provides support to investment firms. She is based in Charlotte, N.C. “Running and cycling aren’t a problem on the road. But try finding a 25-yard pool,” she says. She guides five to six races a year and usually doesn’t meet the athletes until a few days before a race.

“As a guide, strategy is nearly as important as training,” she says. “The athlete’s goal is what matters. If the athlete is having their best day and I’m having my worst day, I should still be comfortably faster than them.”

At the 2017 Ironman World Championship, a course that includes a 2.4-mile swim, 112-mile bike ride, and 26.2-mile run, Ms. Gaynor guided visually impaired South African athlete

Helen Webb.

“The heat was radiating off the pavement and Helen had overheated…on the bike. I cooled her down at an aid station, but having exerted so much energy biking I really struggled on the run. It was grueling.”

The duo finished in 16 hours, 27 minutes and 25 seconds, beating Ms. Webb’s goal of 17 hours. “I don’t know which one of us cried more,” she says.

“The bike course is nearly impossible on a tandem and the run course is very dark, with nearly no visibility,” Ms. Webb says. “I think Caroline is the only female guide with enough experience and mental tenacity to handle the pressure of guiding an athlete there.”

Ms. Gaynor is training to guide a visually impaired athlete in the Ironman Texas on April 28.

The Workout

When Ms. Gaynor’s work-travel schedule picked up last year, she hired

Brad Williams

of KIS Coaching to help her train. “Having a coach has removed a lot of the stress of planning my workouts,” she says. “I’m a competitive person, so I would stay up at night thinking about when I could get in a workout. Brad is the first one to tell me that if a workout is causing me so much anxiety, I should skip it.”

A typical week during Ironman training might include a 90-minute run on Monday. Ms. Gaynor will bike for an hour on Tuesday, with intervals of effort. On Wednesday she does an interval run and Thursday an optional 90-minute ride on a trainer. Friday is an easy 45-to-60 minute run and 2,600 yards of swimming.

Weekends are big training days. On Saturday she will cycle for four hours and Sunday she will run at least two hours and swim 2,000 yards. Her husband is also a triathlete, and they sometimes train together. She tries to do yoga at home or in her hotel room in the evenings and follows sequences on an app.

The Diet

“I’m not the best with diet,” she says. “My watching what I eat means having two cupcakes instead of three.” If she has time, she makes avocado toast before work. Coffee makes her jittery, so she prefers Hiball Energy, an energy drink. Run Gum, a caffeinated chewing gum, provides her preworkout jolt. Lunch is soup and a side salad. She eats light at night. “I just got an Instant Pot and am building a base of stew recipes,” she says. During races, she fuels herself with potato chips and chia gels.

The Gear & Cost

“In an Ironman, wearing a kit that’s comfortable is essential,” Ms. Gaynor says. She buys custom suits from Own Way apparel, which start at around $250. She uses a Garmin Fenix 5S watch ($500) to track her workouts, steps, heart rate, sleep and stress levels. “It also looks like a nice watch, so I can wear it at work without feeling like I’m wearing an athletic watch,” she says. She runs in Saucony Freedom ISO sneakers ($160) and trains on a Wahoo Kickr bike trainer ($1,200). Her coach costs $250 a month and the Yoga Studio app costs about $3. Boldly patterned Handlebar Mustache-brand socks are her signature when racing her bike.

Ms. Gaynor usually covers her own race transportation costs. Guides don’t have to pay race entry fees—they are not technically competing in the race.

The Playlist

“There’s nothing wrong with a little distraction during a long workout,” she says. “I listen to podcasts like ‘This American Life’ or ‘The Moth,’ and sometimes I even talk on the phone when I’m running.”

Write to Jen Murphy at workout@wsj.com