The Ohio native grew up in poverty, but his natural athletic gifts - combined with his relentless work ethic - helped him to become a track and field star at high school.
A life-changing education followed, and even a lucrative NFL contract offer.
An opportunity in rugby then came his way and the rest, as they say, is history.
So when the COVID-19 pandemic hit and sport suddenly became an afterthought, the USA sevens team’s all-time top tryscorer was prepared.
“When the lockdown happened, it wasn't nothing out of the ordinary, because when I was younger, if I didn’t have the equipment or if I couldn't get to training, I found a way," he told Olympic Channel.
His gruelling track sessions were replaced on Instagram by a variety of home workouts, and it was clear that this speedster would not be taking his foot off the gas when it came to training.
"I'm obsessed with getting better and I won’t allow any circumstances from preventing me from doing that. It would eat me up." - Carlin Isles
But C-Fly also keeps it real.
The year 2020 has been difficult for the world on a number of levels, and even his seemingly never-ending energy and inspiration has been prone to down days.
Ultimately though, he practises what he preaches, and training is the one thing that always gets him back on track.
“I keep the objective over any issue. I know what's at stake if you let the mind wander.
"One day I really had no desire to train, no desire for nothing. I never want to play rugby again and just lie down. But then I put my principles in practice and said, 'You know what? This feeling is only temporary, but regardless of that I have to continue to train.’"
"I told myself that somebody else was training to try and take my spot, and that fuelled me.
"I have a warrior mindset because I know how emotions and the mind works, and you have to learn how to conquer these feelings." - Carlin Isles to Olympic Channel
“There may be storms, it may be rainy, there may be hate in the world, it doesn't matter. Most people will drift off, they’ll fall, they'll go hibernate. The thing is, you gotta keep moving regardless of circumstances, because when the sun shines and everything is cleared up, you want to be on the right path.
“So regardless of how I feel, I do. Because I know that what I'm getting out of training and staying disciplined… When it’s sunny again, I’ll be right where I need to be!
“Sometimes you gotta learn how to have a loving and forgiving heart when it comes to certain things. You gotta know how to deal with things in the right manner, stand for what you believe in, and don't don't carry hate.”
Last week, there was another grey day when World Rugby announced that the World Sevens were cancelled with four rounds still to play.
Isles was left in an agonising second place in the tryscoring charts (decidedly low by his standards!), but he was typically philosophical and measured in his reaction to the cancellation.
“It was disappointing. Who doesn't want to compete? We needed as much game time before the Olympics as possible,” the former Glasgow Warriors wing continued.
“However, it gave us a lot of downtime to reflect and think about life and things in general. We can't control it, so we must concentrate on controlling the things we can.
“I'm always about the process. I’ve never really worried too much about accolades and things like that.
“I'm just eager to do everything I can now to be ready, and keep grinding, so that I’m ready to strike when I do start playing again." - Carlin Isles
In what must have started to seem like a never-ending series of blows in 2020, USA Rugby announced in March 2020 that they had filed for bankruptcy.
The decision was largely due to the pandemic, and a hammer blow for the fastest-growing sport in the country.
Both the men’s and women’s teams have qualified for Tokyo 2020 but, thankfully for the players, the governing body’s restructuring will not affect their participation in competitions.
“They're going through some things and trying to figure it out. But, you know, as players, it hasn't really affected us at all,” Isles said.
“As a whole, there may be changes, especially with the staff due to the financial situation which is sad. But other than that, I'm thankful that the players are able to train normally."
As well as the training, Isles also can’t wait to get back to the enthusiastic crowds rugby sevens has become so well known for.
“Sometimes you would get overwhelmed in rugby,” he said. “Sometimes you don't feel like signing autographs and taking pictures when you’ve just lost a tough match. But at the end of the day it's about giving back to the fans in that atmosphere, giving back that love.
“It's a beautiful atmosphere, it really is. The people that you meet from around the world and share encounters with, it is a special interaction." - Carlin Isles to Olympic Channel
While Isles’ motivation to be the fastest man in rugby has not wavered, neither has his desire to push himself.
“I’m always reinventing myself, because so much has happened in my life. I’ll never stop challenging myself and changing things. And that's that's the main thing."
That challenge at the Tokyo Games in 2021, will be to represent Team USA in two sports: rugby and athletics.
Isles did qualify for the USA Track and Field Olympic trials before the Rio 2016 Games in the 100m, but decided to concentrate on rugby sevens given that the sport was making its Olympic debut in Brazil.
“I always felt like I was one of the top sprinters in the US,” the former Ashland University track and field star continued.
“I've been really honing all my speed work and doing little things that I couldn't before, like my body angles and hips.
“I definitely know I can run sub-10 [seconds], without a doubt. I always knew I could, I was just about putting everything together. Maybe even 9.8 [seconds], so I feel like I can do some damage."
If you thought that training to compete in two different sports at the same Olympics would be a distraction, preventing Isles from reaching his potential in either, you’d be wrong according to the man himself.
Far from being a distraction, training for track and field is one of the reasons behind his success in rugby.
“People think I'm crazy, because rugby is hard enough on the body itself. Then I’m going and doing track and field training during my breaks from rugby,” he continued.
“I love running fast, and training for track helps me on the rugby pitch, the two go hand in hand. If I did only rugby-specific training, I would only reach 80 or 85 percent of my potential speed.
“I've got one life, one body, and I’m going to use it to its potential.”
Isles’ Instagram followers will have noticed that he has added another sport to his repertoire during the lockdown: wrestling.
With a desire to maintain his physical edge, and learn some rugby-transferable skills, it is the perfect new pursuit.
“It’s crazy, I feel like if I wasn’t so fast, I'd have been good at wrestling and the fight scene,” he said with a smile.
And it’s clear to see why. It doesn’t take a trained eye to see that his natural explosiveness and fighting attitude lend themselves perfectly to the mat.
“It just comes naturally to me and I love combat conditioning in general. I love a test of my manhood. So I went there and I learned some stuff. A D1 [Division 1 college] who was also a state champ, came up to me and said ‘Man, you are fast!’.
“I took a picture with [wrestling Olympic champion] Jordan Burroughs at the Rio Olympics. He saw me wrestling with my brother and told me, 'Any time you want to wrestle and learn some stuff, hit me up.. so I'll probably do that at some point too.'"
“Wrestling, maybe bobsleigh, I feel I can do a lot of different sports and excel. But now I'm just trying to be the best rugby player, and the fastest man I can be.
“I’ll continue to grind and work hard. My thing is just work hard every day in whatever the future holds.”
American football player, athletics star, undisputed rugby sevens speedster… and now wrestler. At just 30 years old, it is more than within the realms of possibility that Isles may have another reinvention in his Olympic career to go.