The couple exchanged vows at the Woodend Sanctuary in Chevy Chase on Aug. 21. (Aimee Custis Photography)

Marathoners are often reminded during their training to plan ahead and pace themselves — too quick, too soon can cause a loss of steam and momentum. But for long-distance runners Ali Davis and Joe Cafferata, sprinting boded well for their romance.

Just weeks after their first date, the couple sped ahead and booked a two-week vacation to Kenya and Zanzibar to witness the Great Migration. The kicker? They booked the trip six months in advance.

Although excited and optimistic about the trek, neither knew how they would feel — or whether there would even be a “they” — by the start, or end, of their vacation.

“We began joking about it from the minute we booked our trip, like, ‘Can we stay together until Africa?’ ” says Joe, 40.

They circled Sept. 6, 2015, on the calendar. On that date, a day after their big trip, they would meet for brunch and determine whether it had been a complete bust and they should break up, or they should make more plans together.

The pair, pictured at the Woodend Sanctuary in Chevy Chase, met through the DC Triathlon Club’s New Triathlete Program and bonded during the 2013 Ragnar D.C. race. A month into dating, they booked a two-week trip to Africa. (Aimee Custis Photography)

It was a gamble, but luckily Joe was accustomed to having his bets pay off. The State Department civil mechanical engineer has a penchant for spontaneity that has proved successful and rewarding.

For example, when he first signed up to play polo in college, he had never ridden a horse but soon became a skilled player. Years later, on a whim, Joe bought a used canoe on Craigslist and now competes regularly in local regattas.

“If there’s ever a whisper of an opportunity, I say, ‘All right, I’ll do it. That sounds fun!’ ” he says.

Ali, 42, agrees. “He’ll sign up for anything,” she says. “It doesn’t matter what the thing is, but once he puts his mind to it, he goes all in.”

The two had met in May 2013 at a carb-loading pre-race dinner in Washington through the DC Triathlon Club. Ali was training for the New York City marathon, and Joe was interested in competing in local events

“I would run races in New York where it was, like, me and 10,000 other athletic people,” says Ali, a Washington urban planner. “You would go out, run your 10 miles and then go home, which was nice, but I knew I wanted a community.”

Their interaction was quick, but the impression was positive. “I thought she was interesting and fun,” says Joe, who was divorced. Ali felt similarly. “He talked about his engineering work and travels with the State Department,” she says. “I was an engineering undergraduate, and I remember thinking, ‘His job is really cool!’ ”

Flash-forward to October 2013, when the pair reconnected as relay members for Ragnar D.C., a 200-mile nationwide overnight race made up of 12-member teams. During the race, runners must complete three separate legs, each three to 12 miles, over 36 hours. After completing their portion, runners ride along in a shared van to rest, chat and cheer on their teammates.

Because their runs were so close together (Ali was runner No. 8 and Joe was runner No. 9) they had ample time to swap stories between heats. Although Ali didn’t think of Joe in a romantic way at that point, she was taken with how easy and fluid their conversations were, despite the less-than-optimal conditions.

Sleep-deprived, hungry and physically drained, Joe still somehow managed to be encouraging, energetic and enthusiastic throughout the race. “You could always tell who in the van was stressed, moody and demanding. He was none of those things,” Ali says. “He always had a smile on his face.”

Months later, the two met for trivia night at Justin’s Cafe, Joe’s favorite neighborhood bar, at the Navy Yard. There, they connected over their similar career paths and interests, especially travel.

“Together, we have been to 82 countries, 17 of which overlap,” Joe says.

It was there that Ali divulged her plans to celebrate her milestone birthday (40) in Africa. He offered to follow up regarding recommendations, and they soon began exchanging frequent messages on lodging options and activities she could consider.

After exchanging emails and a lot of Facebook chatter, before Ali knew it, Joe was “not so subtly” volunteering to tag along.

“He forwarded me a tour company’s proposal for the trip and I think I said, ‘I totally want to book this!’ His response was, ‘We totally should!’ ” Ali recalls with a laugh.

Maybe if they hadn’t built a solid foundation during Ragnar, Ali would have brushed off Joe’s offer as crazy. But they had, and they spent the next several weeks getting to better know each other. Within a month of their trivia outing, they had booked their tickets.

“We were able to start building common experiences and history in a very deep and quick way,” says Joe.

During the six months before their trip, they trained together, took mini vacations and met each other’s parents. “At some point, I received the VIP black card for Car2go in the mail because I was driving over to his place in Southwest every day,” Ali says, laughing.

The trip brought them even closer as they shared incredible moments, such as witnessing the annual movement of tens of thousands of animals from a hot air balloon over the Serengeti, and some not-so-incredible moments, such as taking care of each other after getting food poisoning.

It was a once-in-a-lifetime opportunity, both say, made all that more special by being able to share it together.

On that fateful, pre-set date, Sept. 6, they sat down for brunch in downtown Washington. Not only did they agree to stay together, they decided Joe would move into Ali’s condo in Mount Pleasant.

A year later, during an early-morning six-mile jog to the Mall, Joe asked Ali to marry him at sunrise on the steps of the Lincoln Memorial.

To conceal the ring, Joe had worn a vest. “It was an ingenious plan, until I realized that it was September and it was still hot outside,” he says.

On Aug. 21, the two exchanged vows at the Woodend Sanctuary in Chevy Chase in front of 130 guests. The groom walked into the ceremony to an instrumental version of “Nothing Else Matters” by Metallica, and the bride came down the aisle to “All I Want Is You” by the band U2.

“Instead of facing each other, we decided to stand side by side and face the audience,” Ali says. “That way, we could see and feel that sense of empowerment, love and support from the audience.”

After the festivities, the couple left for Croatia for another adventure. It was two years, almost to the day, since they had decided to embark on that life-changing trip to Africa.

“I look forward to continuing to grow and build together,” says Joe. “We have been lucky enough to do a lot of really fun things together, and it would be great to keep that up.”

Are you getting married in the Washington region? Tell us why we should feature your nuptials here at wapo.st/weddings.

More from On Love:

A fender bender brings a couple back together after 33 years

She was told 50 first dates was the key to relationship success. He was No. 98.

Wedding trends: Enough with the white dresses