Lactate is fuel. That doesn’t mean the supplement works.

Lactate gels have started appearing in the pro peloton, and the pitch is persuasive. We have spent years correcting the idea that lactate is just a waste product. It is a fuel. Working muscle can use it. It also acts as a signalling molecule.

So the next step sounds obvious: if lactate is useful inside the body, swallowing more of it should make you faster.

That final step is where the evidence stops.

Marco Cardinale wanted a quick answer to that exact question, so he used an AI research agent to run a systematic review and meta-analysis. He searched PubMed/MEDLINE, Europe PMC and CrossRef, pulled 15,871 records, reduced those to 13,079 after duplicates, and eventually included 11 randomised crossover trials with 119 participants, published between 1994 and 2024.

The method is part of the story. This was a scientific analysis, but it was published on Cardinale’s blog rather than peer reviewed. The agent reached its screening limit before completing a planned second reviewer pass. More importantly, the search missed a directly relevant trial that Cardinale later found by hand. He added it, reran the work, and the conclusion did not change.

Across all 11 trials, the pooled performance effect was small and uncertain: g = 0.13, with a 95% confidence interval from −0.05 to 0.31. In plain English, the combined result could still be no benefit at all.

The trained-athlete numbers looked more promising at first. Their point estimate was g = 0.28, compared with 0.07 in non-athletes. That is exactly the sort of split that becomes “works better in trained riders” on a product page. The formal comparison between those groups was nowhere near convincing, so the review does not support that claim.

There is another reason to stay cautious. Four trials reported only that performance was “not significant,” without enough numbers to calculate an effect. Entering those as zero made the main estimate look more precise than the evidence really is. When Cardinale looked only at the seven trials with reported effects, the estimate was g = 0.24 but the uncertainty widened from −0.09 to 0.57. Still no clear win.

The favourable trials were not especially reassuring either. One of the largest effects came from six people using a multi-ingredient drink, so lactate cannot be separated from everything else in it. Another influential result used manufacturer-supplied product. A 2024 pilot found about 3.5% more power in one 20-minute test, but that was one outcome in 15 people, with product and funding from the manufacturer. It is a reason to do a better study, not a reason to buy the supplement.

Even the proposed mechanism remains unresolved. If lactate salts improve performance by raising bicarbonate, the blood chemistry should move first. Across the trials, that effect was inconsistent and uncertain. In the one study that included bicarbonate as a positive control, bicarbonate moved the marker and calcium lactate did not. No meaningful change in the mechanism, no meaningful change in performance.

That does not make lactate unimportant. It means an important molecule has been turned into a marketing shortcut before the performance evidence is ready. Different products deliver very different amounts, most studies are tiny, and some doses caused enough gut trouble to limit what participants could tolerate.

What you do with this depends on which rider you are.

If you’re time-capped: do not spend scarce attention adding an unproven product to a fuelling plan that already needs to work reliably. Get the ordinary food, carbohydrate and fluid plan repeatable first. Complexity is not progress.

If you’re over 50: do not let a new explanation for lactate become a promise that the supplement restores something age has taken away. The current evidence has not shown that. Protect your money and your gut while the research catches up with the story.

If you’re chasing a result, or it’s a new event for you: do not make race day the first meaningful test. If curiosity wins, trial it in training and judge the whole outcome, including tolerability. A product being used near the front of the sport is not proof that it belongs in your plan.

A molecule can be important to performance without becoming a performance supplement.

Source. Cardinale M. Do lactate supplements work? A systematic review run thanks to AI agents to make some sense of the hype. Sports & Fitness Science. 22 August 2026; updated 23 August 2026. Non-peer-reviewed systematic review and meta-analysis. Read the complete analysis. No DOI.

On my mindYou’re looking in the wrong place

I had a call with a rider this week who was enjoying his progress but confused by how it felt. Twelve months ago, he remembered smashing through the mountains and then riding tempo for another hour while everyone behind him suffered. He did not feel like that rider now.

Later in the same call, he said the programming was taking him somewhere he had only reached three or four times in his life. He was doing things on the bike he had never thought possible.

Both things can be true.

The problem is that we compare today’s real sensations with a highlight reel from a year ago. One side is precise and immediate. The other is a vague memory of our best days, stripped of the fatigue, context and ordinary rides around them.

Confidence comes back when you look at the right timescale. What could you do 90 days ago? What can you do now? This rider had just finished a two-hour ride he once did not think was possible. That is not a consolation prize. That is the evidence.

If how you feel does not match what you expected, look at what you can actually do now. You may already be past the place you are still trying to get back to.

This week, name one thing you can do on the bike now that you could not do three months ago. Start there.

— Damian