Zac Clark Praises Fiancée Tayshia Adams' 'Courage' After Finishing N.Y.C. Marathon: 'Inspiring'

Zac Clark raved about Tayshia Adams' performance at the TCS New York City Marathon

Photo: Bryan Bedder/New York Road Runners via Getty

Zac Clark is fiancée Tayshia Adams' biggest cheerleader!

After completing the TCS New York City Marathon together on Sunday, the 37-year-old Bachelorette winner raved about Adams' performance in a touching Instagram post.

"The untold story about @tayshia is one of humility and courage. She would never tell the world how truly inspiring her performance was yesterday at the @nycmarathon but I will," the Release Recovery co-founder wrote, alongside photos of them taken during the marathon.

Clark praised Adams' dedication to the race, saying she was "allergic to excuses" in the weeks leading up to the big event.

"Leading up to Sunday she did dozens of interviews where she could have talked about her chronic knee/back pain or her inability to train due to her insane schedule but instead she talked about her charity of choice, @worldvisionusa, and how grateful she was for all the support from family, friends, fans and strangers," he continued. "She is allergic to excuses. She could have bailed at anytime in the past four months, her PR team would have handled it, but that is just not who she is. She said she was going to do something and she did it."

Clark added, "no one will remember her 'time' but the fact that she went out and ran ... this race in 4 hours and 40 minutes."

He then called Adams' efforts "heroic," noting her performance "shows the power of believing in yourself."

"I will be forever grateful to have had a front row seat to her performance yesterday, as will the thousands of others who cheered her along the way (the screams overpowered the Pearl Jam playing in my ears for most of the day)," he continued. "The world is a better place today then it was yesterday because of you ….. KEEP GOING."

getty Bryan Bedder/New York Road Runners via Getty

Ahead of Sunday's race, Clark told PEOPLE that he planned to stick by Adams throughout the race.

"My commitment to her is that we are going to run together and get her across the finish line," he said. "That's really my focus."

Clark also joked that he was "going to be focused on protecting her and making sure she's able to stay focused on the task at hand, not the next selfie."

Adams also praised Clark for his training method ahead of the race, telling PEOPLE he would wait for her to "ask for help."

"He's really good with advice and steering me in the right direction. He can tell me to run easy today, but knowing myself, I'll probably run hard. But that's okay. It's something of a good balancing act," she said. "He's been really supportive."

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Adams and Clark got engaged last year during her Bachelorette season. In August, the Bachelor in Paradise alum said the couple experienced a rough patch when she left to film Katie Thurston's Bachelorette season.

"I think after that, it was kinda like we need to remember why we were with each other," she said on The Ben and Ashley I. Almost Famous podcast. "And I think that that's absolutely normal. ... It's hard to be in a new relationship and then kind of go away for a couple of weeks, you know what I mean? And this is me being real and honest."

And after crossing the finish line on Sunday, the couple is eager to spend some quality time together.

"We're really looking forward to kicking back after we get done and really spending some time here in New York," Clark recently told PEOPLE. "With our schedules and how everything's worked out, we're just super excited to take advantage of what's here and eat some good food and explore a little bit and make sure that she really feels like she knows New York."