Recent research on fueling techniques can help you make sure you’re fueling wisely before and after strenuous workouts.
Cutting Edge Nutrition
Just a couple of decades ago, endurance sports nutrition was dominated by two main brands of brightly colored sports drinks and a few types of old-school energy bars. Walk into any local running shop or big-box sporting goods store today, though, and you’ll find a dizzying array of options. What’s driving this? Athlete demand first and foremost. If it might improve overall health and performance, many of us will try it.
“We know we are working our bodies hard, and endurance athletes are always looking for an edge,” says Lauren Antonucci, a clinical nutritionist and certified sports dietitian based in New York City.
The other main driver behind this burgeoning industry is the evolving science. Even the most vigilant sports nutritionist would struggle to keep up with the reams of new research being published. As scientists learn more about best practices for fueling and hydration, nutrition companies are working to keep up by providing athletes with the latest and greatest.
Here are some of the most interesting science-backed endurance sports nutrition trends to keep an eye on this year.
Researchers are coming up with new solutions to crush cramps.
For decades, athletes have been told to load up on bananas and down sports drinks to fight muscle cramping. Studies conducted by Harvard neurobiologist Bruce Bean and neuroscientist and Nobel Prize winner Rod MacKinnon suggest that the process may be a bit more complicated. Their research links muscle cramping to hyperactive nerves that send messages from the brain and spine to the skeletal muscle cells. It is thought that fatigue, dehydration and low muscle glycogen can put this process into motion.
“Regardless of the specific factors that trigger cramping, the end result is that some motor nerves become hyperactive, and the muscle cells connected to those nerves go into constant contraction until the hyperactivity is interrupted,” explains Bob Murray, who holds a Ph.D. in exercise physiology and is the managing principal at Sports Science Insights, LLC.
So how might you interrupt this process to prevent cramping? That’s what inspired Bean and MacKinnon to invent HOTSHOT, a 1.7-fluid-ounce sports shot. With the knowledge that certain spices activate ion channels embedded in the nerves of the mouth, they reasoned that they might be able to inhibit the hyperactivation of the motor nerves via a sharp-tasting drink, thereby preventing cramping.
So far results from studies done at Penn State University have shown promise in demonstrating how an athlete’s muscles and nerves work together to affect performance—and the role a drink like HOTSHOT might play in reducing cramps—but there is still plenty of ongoing research.
“The science is really interesting,” Antonucci says. “You still need to hydrate and take in salt, but this gets at the other side of the possible cause of cramps—the nerves.”
Health and performance are linked to the state of our microbiome.
New research is revealing that microbes in the digestive system can affect things like weight, immune function and—you guessed it—endurance performance. The microbiome is the bacterial community that lives on and within us that has major implications for human health, and researchers have become particularly interested in how the microbes in our guts might influence athletic performance.
The most interesting findings as of late come from Jonathan Scheiman, a researcher at Harvard Medical School, who gathered fecal samples from runners who competed in the Boston Marathon. At a meeting of the American Chemical Society last summer, he reported to have identified a type of bacteria in large numbers in runners soon after they finished a marathon. The thought is that strenuous exercise causes this bacteria to build up in the bloodstream and then works to break down lactic acid, which is associated with fatigue and soreness.
The result of this emerging science? Scheiman founded Fitbiomics, a startup that’s working to create a probiotic that reduces fatigue and improves endurance performance.
Board-certified sports dietitian Bob Seebohar says that while there is still much we don’t yet understand, this is something we should be paying attention to, saying, “I believe all athletes should be focusing on improving their gut health, whether it be through taking probiotic supplements or consuming gut-friendly bacteria through foods like kefir, kombucha and other fermented foods.”
What’s right for one athlete’s gut isn’t for another.
Another wing of the body of research looking into the microbes in our digestive systems is pointing to the fact that because every gut microbiome is different, we should tailor our nutrition accordingly. One project, dubbed the “American Gut Project” out of the University of California San Diego, is gathering samples from the general public and so far has discovered that there is great diversity when it comes to our microbial content.
Following suit, a number of personalized nutrition companies are entering the market, helping to base clients’ nutritional intake on their individual gut bacteria. One of those is DayTwo, an Israeli company co-founded by marathon runner Eran Segal, which recently announced a collaboration with the Mayo Clinic. By analyzing a person’s microbiome, they work to predict blood-sugar responses to different foods to improve health and performance.
So might this improve running performance? Antonucci suggests that while promising, “we still need to know what specifically athletes need in their gut before we know what to put in there. We are making great strides in understanding the gut health for endurance athletes, but there’s more work to be done.”
Hydrogel technology allows for more effective absorption of carbohydrates.
We know that carbohydrates are essential for endurance performance, but many runners experience GI distress when trying to take in the recommended amounts of sugar on the run. This is where the idea to encapsulate or compact high concentrations of carbohydrates in a hydrogel was born. The resulting company, Maurten, is producing a new type of sports drink and working with nutritionists, doctors and researchers around the world to study its efficacy.
While hydrogels are nothing new in the food industry (they’re frequently used as thickeners and structurants), utilizing them in this way is somewhat groundbreaking. The neutral-tasting liquid drink transforms from liquid to gel form when it interacts with acid in the stomach.
“If you take a really close look at the gel on a nano level, it consists of a structure that looks like a kitchen sponge,” explains Herman Reuterswärd, head of communication at Maurten. “In the pores of this structure, the carbohydrates are trapped or encapsulated.”
From there, the hydrogel allows for the smooth transport of the drink from the stomach to the intestines, where it can be effectively absorbed. This means that an athlete can tolerate higher amounts of the important carbohydrates that fuel endurance performance without the high risk of GI distress.
Most notably, the science behind Maurten has also gotten buy-in from Yannis Pitsiladis at the University of Brighton who ran the Sub2 project. It’s also how Kenenisa Bekele started using the drink in training and during one of the fastest marathons in history (the 2016 Berlin Marathon) which bodes well for the future of this new technology.
Ketones may offer a new type of endurance fuel.
We have long known that a low-carb, high-fat (LCHF) diet causes the body to produce ketones in the liver, which can then be used as energy. Unfortunately, for many there are significant downsides to employing this type of diet. This led scientists and athletes to wonder if it might be possible to take a ketone supplement to reap the benefits of this more efficient source of energy without actually having to follow a LCHF diet. As such, researchers at Oxford gave cyclists a proprietary ketone drink called HVMN (pronounced “human”) and found that their performance did indeed improve, riding an average of 400 meters farther during a half-hour time trial.
“Ketones are a more efficient source of energy for the body than glucose or fat. Glucose use for energy during elite performance is limited by the amount that can be taken up from the gut,” explains Kieran Clarke, a professor of physiological biochemistry at Oxford who led the study. “The cyclists who rode 400m farther had both ketones and glucose, in effect an extra fuel, rather like a car being able to run on diesel, petrol and electricity at the same time.”
In addition to providing an alternative energy source, Clarke says that the ketone drink decreases the rate of glycogen depletion, so an endurance athlete staves off that point of “hitting the wall.”
Other recent research conducted at the Australian Institute of Sport actually found that ketone supplementation impaired endurance performance and caused stomach upset. The study was short-term, and the riders’ stomachs may have acclimated to the drink over time, so the jury is still out.
Clean ingredient lists take over.
A growing body of research that questions the safety of a number of food additives and fillers has had a profound influence on endurance nutrition in recent years. As a result, a new class of products has come to market with fewer fillers and excess sugars that are thought to potentially cause trouble for athletes.
“During exercise, the gut is under the stress of heat and hypoxia (low oxygen) due to the fact that blood is being diverted to the working tissues and heat is being produced from exercise,” explains senior research fellow at University of Waikato, Stacy Sims, Ph.D., also the co-founder of Osmo Nutrition who helped formulate Nuun’s new natural Performance drink. “When you ingest fillers and flow agents, even in small amounts, it increases the stress on the gut and kidneys, which can lead to GI distress, inflammation and a perturbation of the gut microbiome.”
While the definition of “clean” ingredients and products varies depending on whom you ask, for Nuun’s Performance line, Sims relied on vegan and non-GMO sugar sources, meaning they haven’t been oxidized through the charred remains of animal bones, but rather, through wood charcoal. Other products, like Gatorade Endurance, have had artificial coloring removed from their formulas.
“My suggestion is to look for products that contain minimal ingredients, only what is best utilized during a workout or race—electrolytes and sugars/carbohydrates,” adds Marni Sumbal, a board-certified sports dietitian and 12-time Ironman athlete.
Carbohydrate-fasted workouts gain increasing support.
While the importance of periodizing training—changing volume and intensity to boost fitness—is well understood, a similar approach to nutrition is becoming widely accepted thanks to a growing number of studies that support the practice. Most notably, this is done through carbohydrate-fasted workouts, which involve withholding carbohydrates prior to specific workouts.
“What the research has shown is that training in a glycogen-depleted state stimulates mitochondrial biogenesis, which increases aerobic capacity and thereby enhances endurance performance,” explains Matt Fitzgerald, a certified sports nutritionist and author of TheEndurance Diet. “That’s why even short, high-intensity carb-fasted workouts are beneficial and why performance is improved even in relatively short time trials where fat-burning capacity is not a limiter.”
Indeed, the research has demonstrated the efficacy of this strategy for cyclists, triathletes and runners alike. Even still, in order to avoid dips in performance, Sumbal suggests, “if you’re considering fasted workouts, consult with a board-certified sports dietitian for help.”