Published June 26, 2026 12:03PM
Here’s a subplot to watch for in the upcoming Tour de France. A company called From Lab to Field, or FLF, emerged from secrecy earlier this month (as Jim Cotton reported for Outside’s sister publication Velo) to reveal that it has developed a new energy gel that includes lactate, of all things. The gel isn’t yet for sale, but the company produced a preliminary batch of tens of thousands of gels. Seven World Tour teams tried to buy them for this summer’s Tour—but one team got there first and bought up the entire production run to ensure they would be the only ones with access.
Let the hype, and the speculation, begin!
The physiologist behind FLF is Aitor Viribay Morales, who spent three years as lead scientist for the INEOS Grenadiers cycling team and is currently head of global sports performance for Salomon. He teamed up with food scientists from the Basque Culinary Center and chefs from the Michelin-starred northern Basque restaurant Mugaritz, for reasons we’ll come back to. The result is—well, we don’t know yet. But in the wake of recent sports nutrition innovations like hydrogel sports drinks and baking soda, there has never been more interest in finding the next big thing.
Why Lactate?
Lactate has a complicated history (as I explored in detail here). Starting in the early 1900s, physiologists thought that “lactic acid” was a waste product generated during hard exercise because you couldn’t get enough oxygen, and it caused your muscles to fatigue and feel a burning sensation. As it turns out, we don’t actually have lactic acid circulating in our bodies; we have its two constituent parts, hydrogen ions and lactate. The former causes problems; the latter is actually helpful.
In fact, there’s a whole line of research called the “lactate shuttle” hypothesis, originated by University of California at Berkeley physiologist George Brooks, that argues for a grand and multifaceted role for lactate. It’s a fuel, like fat and carbohydrate—but not just any fuel: it’s the preferred fuel for muscles, heart, and brain, capable of circulating from one part of the body to others where it’s needed. It’s also a signaling molecule, cueing the body about which forms of fuel to use at any given time and perhaps even triggering training adaptations.
All of these benefits have been studied for the lactate produced naturally in the muscles during hard exercise. So why don’t we just drink lactate? Mainly because it’s impossible to stomach, much like ketones were a decade ago. That’s where Viribay’s collaboration with food scientists and chefs comes in.
Exactly how FLF has solved the problem remains confidential while patent applications are in process. Viribay told me via email: “Long story short, we have used chemical and physical properties to ‘tame’ our friend lactic acid. Chemically, we have discovered a way to buffer it with high efficiency. Physically, we have discovered a matrix that makes it digestible and palatable.”
What Does the New Gel Do?
According to a launch webinar, FLF’s new ExoLactate gel contains 40 grams of carbohydrate and 5 grams of lactate. They figure the right dose of lactate during endurance exercise is between 10 and 25 grams per hour.
The idea is that lactate will function as a separate, parallel fuel pathway alongside carbohydrate. There’s a precedent for this. Two decades ago, scientists thought that the body could absorb a maximum of about 60 grams of carbohydrate per hour, because the transporters that brought carbs out of the intestine and into the bloodstream were maxed out. Then they figured out that different types of carbohydrate use completely different transporters—so if you combine glucose and fructose, for example, you can increase your absorption to 90 grams per hour because you’re using two different sets of transporters. There’s a similar effect for lactate, which uses yet another set of transporters. So with two types of carbohydrate and lactate, you can leverage three different transporters and get even more fuel in.
There are other potential advantages. For example, glucose and fructose need to be processed in the liver before being used as fuel, which means it takes 15 to 30 minutes from the time of ingestion before they’re consumed. Lactate, on the other hand, goes directly into the bloodstream and starts being used within five minutes.
What lactate does once it’s in the bloodstream depends on the context, according to Viribay. If you’re exercising at a low to moderate intensity below threshold, the extra lactate will reduce your reliance on carbohydrates and promote fat burning. Above threshold, on the other hand, oxygen is scarce, so lactate will switch its behavior: it will promote carb burning and inhibit fat burning, since carbs use oxygen more efficiently. In other words, it’s a win-win situation.
Does It Actually Work?
That’s the theory, anyway. Viribay is the first to point out that the existing research on exogenous lactate is somewhere between thin and non-existent. He and his colleagues have a scientific paper under review, and they’ve been testing in the lab and with pro athletes for 18 months now. In the webinar, he showed pilot data demonstrating the effects on carb and fat oxidation. He also showed time-to-exhaustion performance in seven subjects cycling for roughly 20 minutes:
The control condition is in red. The results are intriguing, with an average improvement of around 8 percent—but that’s dominated by two subjects who had massive improvements of over 20 percent each, so you can’t read much into it. Based on a broader look at their testing data, Viribay estimates—very tentatively—that on a climb like Alpe d’Huez, which takes somewhere around 45 minutes, lactate might slice 60 to 80 seconds off your time.
I exchanged emails with a pro cyclist who has been trying the gel for six months, using it both in training and in racing. He has used up to four gels an hour, for a total of 160 grams of carbohydrate and 20 grams of lactate, without stomach issues. He figures that on the basis of taste and palatability, in a blind test, no one would even be able to tell the difference between the new gel and a standard carbohydrate gel. He thinks it helps, but admits that it’s hard to tell for sure in the messiness of real-world training and racing.
The situation reminds me a lot of ketones, which a decade ago were all the rage in the peloton. There were plenty of theoretical reasons to think that ketones should be a superfuel. The reality has been more complicated: they haven’t been “debunked,” and they continue to be used by some athletes. But their usage case has turned out to be more nuanced than anticipated, and scientists are still exploring new ideas like using them to help ward off altitude illness. Viribay, in his webinar, suggested that it may take years to unravel the various ways that external lactate acts in the body.
The gels should go on sale to the general public later this year, at a price Viribay describes as “similar to current high-end gels.” He’s also soliciting collaborations with researchers to test the new gels. For now, though, all we can do is reserve judgment—and watch carefully over the weeks to come to see which Tour de France team is taking some unfamiliar-looking gels, and whether they seem to be exceeding expectations.
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