One could say Brett O'Brien knows a thing or two about fueling for performance. He's been leading the sports drink and performance food brand Gatorade since 2012.
"Literally, my professional life is all about fueling athletes and making sure that they're hydrated properly," O'Brien, senior vice president and general manager at Gatorade tells CNBC Make It.
But O'Brien — who dabbles in amateur competitions himself from time to time, competing in a few marathons and several triathlons over the years — had to make some mistakes before he got things right.
During the Boston Marathon in 2014, two years after getting called up by PepsiCo executives to lead Gatorade, he almost had to stop running because he was so dehydrated.
"I didn't know what I was doing," O'Brien says. "It was unseasonably hot that day [in Boston]. I think it was around 72 degrees [and while] I work in hydration, it completely threw me off."
The experience prompted him to get smarter about his own routine and what he was putting into his body.
"I got a lot smarter about electrolytes and about hydrating ahead of time," he says.
But the trick that really helped O'Brien turn his fitness routine around, he says, was keeping a log of his workouts and how he performed, even if it was a small jog.
"I've literally have written down every single workout I've done for the past five years," he says.
The specific tracking, he says, has helped to motivate him by showing his monthly — and yearly — results as well as certain trends he's seeing in his performance level.
"Its also kind of a game I play with myself when I'm traveling for work. It motivates me to work out on the road and see all the different cities that I've traveled in year over year."
And O'Brien could be on something. While the benefits of journaling are far from new, as experts and even studies have linked daily food logging to weight loss, trainers have also touted that a fitness journal can make you a more efficient athlete.
"Maintaining a fitness journal can be one of the most impactful things you can do for your own training," Matthew N. Berenc, director of education at the Equinox Fitness Institute in Los Angeles, California, told Men's Health in February.
According to Men's Health, writing down your fitness habits can put you in a better position to repeat past successes and build on them. O'Brien says his log has helped him understand his training capabilities better and learn where he needs to improve the most.
He also says he felt accomplished when he tallied up all the miles he ran, biked and swam each year.
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