His fast-twitch fibres have taken him from American football to the athletics track and he has now found a new home on the rugby field for the United States sevens team.
The 23-year-old has a personal best time of 10.24 seconds over 100m and once ran a wind-assisted 10.13 - times that could have seen him qualify for the semifinals at last year's London Olympics.
It wasn't fast enough, however, to make the highly competitive US Olympic team and once Isles realised this last year he went looking for another avenue to get to the world's biggest sporting event.
Sevens are set to debut at the Rio Games in 2016 and countries such as the United States are investing big money in their teams to achieve Olympic success.
Inspired by another American footballer who crossed over to rugby, Miles Craigwell, Isles went about finding his way into the game.
He got in touch with USA Rugby chief executive Nigel Melville midway through last year and his rise to the national sevens set-up has been quicker than his pace on the field.
Isles debuted for the US at the first leg of the sevens world series on the Gold Coast in October and scored his first try after less than a minute on the field.
Since then he has found his way to the line five more times as the US coaches try to familiarise him with the game.
"I realised I was fast when I was 8," he recalled. "I played [American] football and I was just outrunning people and people always told me I was fast but it took me a while for it to sink in.
"For me, I always wanted to be the fastest wherever I go. But as I got to middle school school I was the fastest. I was the fastest in elementary school then I became the fastest at high school and then I was the fastest in college and that's where it really started off."
The speedster looks up to the likes of Wallabies pivot Quade Cooper, Welsh wing Shane Williams and South African flyer Bryan Habana in the 15s game.
With only six months of experience on the rugby field, Isles has taken on a whirlwind education to pick up the intricacies of the game.
"I've just been working on other tactics, kicking. Just other outlets because people are going to start playing me differently. Just the things to enhance my performance, the things I need to do to be better; reading lines better and it's all coming together."
His agent is working on a potential contract with a team in France and a stint in the 15-a-side game looks inevitable given what he could offer a team with his speed.
But at only 75kg and standing at 1.73m, he would be a small man in a increasingly bigger-man's game. Having played as a running back and cornerback in American football, his defence in rugby has had to catch up but he insisted he loved the contact side of the sport.
"We work a lot on tackling, so the tackling's good."
Isles doesn't lack confidence and he will need it this weekend when the US meet favourites New Zealand, 2009 winners England and Spain in Pool A at the Wellington sevens.
The world series-leading New Zealanders meet the US in the final game of the day today. A dash of Isles' speed might help their cause.
