Set aside the neon-colored sugar water—scientists have created a new performance-enhancing beverage, and it’s already producing some impressive results for endurance athletes, helping them push further and feel less sore. That's according to researchers at the University of Oxford and the U.S. National Institutes of Health, who developed the drink as part of a study funded by DARPA, which wanted to create an efficient, nutrient-packed food that could keep soldiers performing at their peak on the battlefield, and U.K. Sport, which saw the obvious benefit for endurance athletes.
Unlike the familiar sports drinks you’re used to chugging at the gym, this new drink isn’t packed with sugar. In fact, it has very little sugar at all.
The not-so-secret ingredient? Ketones. You've probably heard of ketogenic diets. They theoretically "train" the body to generate energy from ketones by removing almost all carbs and introducing a lot of dietary fat, which the body can start to rely on for its primary source of ketogenic energy. Stay with us here. Ketones are organic compounds that the body can use to generate energy. The body normally does this processing fats to create ketones, but it can also consume available ketones (as is the case in this experiment). The study report says that the drink was almost entirely liquid ketones. (Imagine drinking non-toxic nail polish remover.) They had to put a lot of aspartame in it to mask the flavor. More on this in a bit.
"It's really interesting; with a single drink of nutritional ketone you can do the same exercise with completely different metabolism," Pete Cox, M.D., a clinician at Oxford and the lead study author, told Medical News Today.
How’d the researchers test it?
Over the course of six different studies, researchers rounded up 39 highly trained cyclists, some of whom were former Olympians, and gave them one of three “energy drinks” infused with either carbs, fats, or ketones, according to the study published Wednesday in the journal Cell Metabolism. The cyclists didn’t know which they’d received.
The cyclists completed a range of aerobic workouts, each about an hour long, and working at about 75% of their predetermined maximum effort.
After looking at the cyclists’ workout results, researchers found that the cyclists who consumed the ketone drink rode about 400 meters farther over the course of 30 minutes of exercise. Moreover, the ketone drinkers had lower levels of lactic acid in their blood—which, as any endurance athlete knows, causes post-workout achiness.
Why does the ketone drink work for endurance cyclists?
Some more exercise science: When you work out steadily for long periods of time, your body creates energy by breaking down carbs and sugars (specifically glucose) to produce ATP and power your muscles, a process called aerobic respiration.
But when the human body is running seriously low on glucose (as in starvation-level lows) it switches from burning carbs to burning ketones—a process called ketosis—which it generates by processing fat.
Here’s where it gets interesting: The researchers argued that the ketone drink basically encouraged the cyclists' bodies to switch from standard glycolysis to ketosis, even though their bodies had plenty of glucose available.
“The ketone itself is inhibiting glycolysis"—a part of aerobic respiration—"so that with the same exercise you're preserving glycogen and producing much less lactic acid,” Kieran Clarke, Ph.D., a biochemist at the University of Oxford and a co-author on the study, told Medical News Today. “This hasn't been seen before. What may be happening is if you are doing something that isn't a sprint, like going on a 26-mile run, you won't hit the wall as quickly. Not only that, but it stops you from aching afterward.”
That anti-ache effect? It’s because ketosis doesn’t produce lactic acid. Less lactic acid means less ache.
Would it work for a weightlifting workout, too?
Remember how we talked about aerobic respiration, and how it’s the body’s preferred method of generating energy from sugar? It works fine for long-term exercise. But when you’re doing something that requires a ton of energy really quickly—like a 400-lb deadlift or a 100-meter all-out sprint—your body generates energy with other methods that don’t involve oxygen. (That’s why short sprints and weightlifting are called anaerobic exercise.)
Ketosis, on the other hand, requires oxygen to work. So while it can provide energy for long-term aerobic exercise, it doesn’t work for short-term anaerobic exercise.
Can I get my hands on it?
Clarke told Medical News Today that the ketone drink will be available within a year, although she said it isn’t meant to replace everyday nutrients.
The only possible hurdle? As mentioned, the ketone compound the researchers used (D-β-hydroxybutyrate-R 1,3-Butanediol Monoester, in case you were wondering and/or an organic chemist) is “extremely bitter.” The scientists masked the flavor in the experiment by adding aspartame aka NutraSweet, aka Equal. But “extremely bitter” is probably not the easiest sell for a mass-market sports drink.