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There’s a reason we call nutrition triathlon’s fourth discipline: Fail to nail that critical piece and it doesn’t matter how much you’ve trained, your body won’t respond. Ace it, and you could conquer athletes whose VO2 max would put yours to shame. As these seven pioneers discovered, fueling for peak performance is so much more than calories in, calories out. It’s about timing, community, individuality, and hard, cold science.
Asker Jeukendrup, Ph.D., 48
An athlete from a young age, Jeukendrup always had an interest in sports and all of the factors that contributed to his performance, including nutrition. After graduating with a degree in Human Movement Sciences at Maastricht University in the Netherlands, he completed his Ph.D., focusing on the “Aspects of carbohydrate and fat metabolism during exercise.” Jeukendrup went on to become a professor, and then he began to delve deeper into sports nutrition research while continuing to pursue his own athletic endeavors.
What Happened Next
Over the last 20 years, Jeukendrup has worked with the likes of Chrissie Wellington, Andreas Raelert, and the Rabobank Pro cycling team. A triathlete himself, he’s completed 21 Ironman events, including six visits to the Ironman World Championships. And he has spent as many hours in the lab as he has on his bike, with stints as the editor-in-chief of the European Journal of Sport Science and director of the Gatorade Sport Science Institute.
“My nutrition philosophy is based on seven key areas: Evidence-based; focus on performance; back to basics but doing it well; real foods; education is key; personalized and periodized; and long-term view,” he says. “There are no shortcuts and no magic potions. If you want to achieve something, you have to work hard.”
After years of gathering knowledge through both his professional and personal experience, Jeukendrup decided it was time to make his evidence-based advice more accessible to everyday athletes as well, creating Mysportscience.com, a place where he distills the latest nutrition research for the masses, and helped launch nutrition–planning service CORE at Fuelthecore.com.
Jeukendrup has been published in over 200 peer-reviewed publications and book chapters in the field of sports nutrition, many of which have been used to help formulate the guidelines we have today. His research on carbohydrate recommendations during exercise, for example, led to what the International Olympic Committee quoted as two of the four most important findings in the last 50 years: 1. That for endurance exercise over two and a half hours, athletes should take multiple transportable carbohydrates (e.g., glucose or fructose) at a rate of 90g/hour, and 2. That for exercise lasting one hour (or less), a carbohydrate mouth rinse is sufficient to improve performance.
The Women’s Advocate
Stacy Sims, Ph.D., 44
It didn’t take long in her studies at The University of Otago in New Zealand in the early 2000s for Stacy Sims to recognize that most sports nutrition/exercise science research had been performed exclusively on male athletes up until that point. “For so long women have been excluded or have been given generalized guidelines from research done on men,” says the Ironman athlete. This revelation left the environmental exercise physiologist and nutrition scientist wanting answers— both for herself and her friends who were trying to perform at their best.
What happened next
She focused on hydration and hyperhydration for her doctoral thesis, addressing how fluid availability and plasma volume shifts in both men and women, and then continued to perform sex-specific sports nutrition research at Stanford University for the next five years. Sims has been a pioneer in studies that look at how nutrition specifically affects female athletes ever since. “My academic career has been focused on looking at how women differ from men and finding ways we can garner those differences and use nutrition to help empower all athletes to work with their physiology, not against it,” she says. She went on to co-found Osmo Nutrition, where she served as the company’s chief research officer, and has consulted for USA Cycling, Clif Bar, and Nuun, among others.
Sims stands out because she was the first to talk about taking women’s menstrual cycles into consideration when creating nutrition plans, in an effort to better match their food/nutrient needs with their hormonal flux and performance goals. The concept received a bit of pushback in the beginning, but has garnered more attention recently as female athletes seek new avenues for smart performance gains. Her research continues to influence how female athletes choose to train, eat, and hydrate. (For example, women need to work harder to stay hydrated in the days just before their period, she suggests.) “By taking a more personalized approach to fueling and recovery, plus using windows of opportunity to maximize adaptations, not make it harder, we could give female athletes the ability to reap better results from their training,” she says.
The Cooking Coach
Allen Lim, Ph.D., 44
Allen Lim had just graduated from CU Boulder with a doctorate in exercise physiology in 2004 when he had his breakthrough moment. He was training a cyclist, who didn’t know how to cook and basically ate like he was living in a college dorm, for the Tour de France in Girona, Spain, when Lim realized that sports nutrition wasn’t just about bars and gels, that athletes also needed to learn how to prepare and eat normal, healthy food. “I found myself trading in my lab coat for a pair of apron strings and began making and teaching athletes simple, delicious, meals that I had learned cooking with my mom and dad as Asian immigrants in Los Angeles,” he says.
What happened next
Lim continued to tinker with his athletes’ nutrition until he ultimately founded his very own packaged sports-food company, Boulder-based Skratch Labs. Their goal: “To make real food that doesn’t taste like crap and actually helps athletes perform better,” he says. He also started encouraging athletes to eat family-style dinners instead of chowing down solo, as a way to create and maintain a sense of community around enjoying healthy food.
Yes, Lim has helped develop a product line that triathletes like two-time Olympian Tyler Butterfield swear by. But he’s also made it his mission to get more athletes into the kitchen, educating them on how to make meals and snacks that they can consume before, during, and after exercise through his Feed Zone Cookbook series. To that end, his mission is still a work in progress. “If you’re burning a lot of calories as a high performing athlete, you have to eat a lot,” he says. “Being able to do that in a way where the food is fresh, locally sourced, shared with others, and is as beautiful as it is delicious is a great way to make what we eat not just something that makes us better, but also one of the best parts of each day.”
Bruce Bean, Ph.D., 65, and Roderick MacKinnon, M.D., 61
Neither Bruce Bean, a professor of neurobiology at Harvard Medical School, nor Roderick MacKinnon, a professor of molecular neurobiology and biophysics at Rockefeller University, ever planned to enter the world of sports nutrition. But the two seriously smart friends (MacKinnon has won the Nobel Prize in Chemistry) were out sea kayaking together, staying well-hydrated and fueled, when rather unexpectedly, they both started cramping badly in their arms—and it got them thinking: What exactly causes muscle cramps, how do you prevent them, and why didn’t either of them know more about it? “We quickly discovered that everything we’d read about the subject in medical school—that it was caused by dehydration or an electrolyte imbalance or lactic acid build-up— turned out to not be true,” Bean says.
What happened next
“We eventually found (in the basic science literature) some properties of muscle cramps that led us to real- ize that the fundamental origin of the cramp resides not in the muscle itself, but rather in the nerves that innervate the muscle,” MacKinnon says. Essentially, cramping occurs when there is excessive firing of the motor neurons in your spinal cord that control muscle contraction. Given that they’re both biophysicists who study neural signaling, they were then determined to find a way to inhibit this effect.
These two are leading the charge in a category poised to be the next big thing in sports nutrition: neuromuscular performance. Triathletes will likely most likely recognize the consumer result of their research: Hotshot. This spicy concoction containing capsaicin, ginger, and cinnamon has been proven effective in inhibiting both electrically-induced and natural cramps. It works by stimulating sensory nerves in the mouth, before the effects spread throughout the entire system. “There’s always a balance of excitation and inhibition of a neural circuit. With cramping, there’s too much uncontrolled excitation. Our idea was that if you could stimulate the neurons that respond to sensation, exciting them naturally with ingredients like capsaicin (in hot peppers), then you’d also tune up the overall inhibitory parts of the circuit,” Bean says.
And while its initial product is directed toward athletes, their company’s focus includes developing innovative treatments for cramps and spasms asso- ciated with severe neurodegenerative diseases, such as ALS and MS. “The common denominator is there’s a hyperactive nerve, and we need to calm it,” says Hotshot spokesman (and Gatorade Sport Science Institute co-founder) Bob Murray.
The Paleo Promoter
Loren Cordain, Ph.D., 66
In 1987, Loren Cordain was teaching at Colorado State University in Fort Collins when he read Dr. Boyd Eaton’s classic paper about the paleo diet in The New England Journal of Medicine. He thought it was the best idea he’d ever heard about optimal human nutrition. Cordain reached out to Boyd and learned as much as he could about the concept, which basically involves a diet that’s rich on lean animal proteins and eliminates processed foods. Cordain’s first book, The Paleo Diet, was published in 2002, selling more than 100,000 copies and garnered a cult-like following, particularly among CrossFitters.
What happened next
Cordain co-authored his second book, The Paleo Diet for Athletes, with famous triathlete coach (and Cordain’s running partner) Joe Friel in 2005. “My original intention with the paleo diet concept was to help people with health issues (hypertension, high cholesterol, heart disease, diabetes, obesity, etc.) overcome their problems,” Cordain says. But given that he was a member of the track team at the University of Nevada, Reno, the head lifeguard at Sand Harbor State Beach in Lake Tahoe for almost 20 years, and married to a marathoner/triathlete, it seemed natural for him to introduce the paleo concept to the endurance sports world as well. “I suspected that athletes could also improve their performance with contemporary paleo diets,” he says. “Then along comes Joe, an international caliber triathlete coach, to prove it with many of his nationally and internationally ranked athletes.”
Regardless of your thoughts on paleo, there’s no denying that Cordain has changed how a number of world–class athletes approach nutrition and fueling. He shifted the focus from the traditional concept of carbo-loading to consuming fresh foods, lean proteins, fruits, and veggies most of the time, and then limiting carbs to just during and immediately after exercise—all in an effort to reduce recovery time, prevent muscle loss, and boost the immune system. “Joe also found that certain carbohydrates were more effective than others in restoring muscle glycogen, particularly specific types of sugar, such as glucose and net alkaline-producing starches in bananas, potatoes, sweet potatoes, and yams,” he says.
The Green Guru
Brendan Brazier, 42
On a personal quest to find food that would help him perform better, Brendan Brazier tried just about everything possible until he finally landed on a clean, plant-based diet that naturally worked to reduce inflammation and increase mobility. But trying to maintain that diet while training as a professional triathlete was far more difficult than he’d anticipated. “I found myself on a mission to try and figure out how to recover more quickly, especially once I started doing longer events,” he says. At the time, the market was mostly full of whey- and soy-based proteins —they weren’t complete proteins or anti-inflammatories and didn’t provide nourishment to the adrenal glands, which make hormones, like cortisol, that help regulate the body’s response to exercise and other stressors.
What happened next
Brazier, who has had three top-15 Ironman finishes and won two 50K running national championships, started experimenting in his own kitchen with hemp protein, fresh veggies, yellow pea protein and Chlorella, an algae that is 70 percent protein and can lower cortisol. He developed a recipe for what would eventually become Vega’s very first recovery smoothie, launched in 2004. “Triathletes tend to be highest group of over-trainers, for obvious reasons. There’s no shortcut, you have to put in those workouts to get your body ready. You can’t pack in more training, but if you can be more efficient with your nutrition, that makes a difference,” he says. “Choose to eat foods that are easier to digest and return more nutrients. Your muscles don’t have to work as hard to move if they’re being fueled properly.”
Athletes of all levels now look to Vega for an easy-to-digest source of plant-based proteins. Brazier also devotes a lot of time and energy to educating others about performance nutrition, so they can make good choices (and meals) on their own. He’s written a bestselling book series, Thrive, and now has a free web series, called Thrive Forward, that provides how-to cooking videos, meal plans, and recipes to athletes looking to ditch the meat. “That’s the root of it all, helping people learn to make recipes that are synergistic with the right amount of carbs, protein, fat. We open-source information to get better quality food to more people, regardless of whether they buy any products,” he says.