Science & ingredients
Sodium bicarbonate vs beta-alanine vs lactate buffers: which one, when
Three supplement categories claim the same job: keeping muscle pH stable when you're deep in the red. They work on different timelines, in different places, with very different evidence. Picking between them is mostly a scheduling question.
Where each one works
Your body fights acidity on two fronts. Inside the muscle cell, carnosine soaks up hydrogen ions at the source. In the blood, bicarbonate pulls H+ out of the muscle and neutralises it.
Beta-alanine builds the inside defence. Bicarbonate stacks the outside one. Lactate buffers claim a third route, consuming H+ as lactate gets metabolised, though the evidence there is the weakest of the three.
Sodium bicarbonate: the race-day option
Timeline
Works in hours. 0.2-0.5 g/kg, taken 60-180 minutes before.
Evidence
Strong. The ISSN position stand backs it for efforts of 1-12 minutes and repeated sprints.
Cost
Pennies, unless you go for hydrogel delivery.
The catch
Gut risk. A large share of athletes get GI symptoms at race doses. Trial it in training, split the dose, take it with carbs. Full protocols in our bicarb guide.
Beta-alanine: the training-block option
Timeline
Works in weeks. 3.2-6.4g daily for at least 4 weeks before you'd expect a difference.
Evidence
Strong. A 40-study meta-analysis found gains in 30-second to 10-minute efforts.
Cost
Roughly 20-40p a day.
The catch
Commitment. Miss the loading window and race-week doses do nothing. Higher single doses cause harmless skin tingles. More in our beta-alanine for Hyrox post.
Lactate buffers: the daily-formula option
Timeline
Marketed for daily use in the lead-up to competition.
Evidence
Mixed. The theory is plausible, but a controlled trial of chronic calcium lactate found no improvement in blood buffering or repeated sprint performance. We've graded the full evidence base in do lactic acid buffers actually work?
Cost
Varies wildly between brands. Check the per-serving price and whether doses are actually printed on the label.
The catch
The category leans on the lactate story while the working ingredients are often the electrolytes and amino acids beside it. Ours carries 225mg magnesium, 525mg potassium and 1g taurine per serving for exactly that reason, and we print every dose.
Can you stack them?
Yes, and the mechanisms suggest they're complementary: carnosine inside the cell, bicarbonate outside it.
A sensible Hyrox season stack: beta-alanine daily through the block, your daily buffer-electrolyte formula as the consistent base, bicarb trialled in training and deployed on race day only if your gut signs off.
The decision in one table
Bicarbonate
Beta-alanine
Lactate buffer
Works in
Hours
Weeks
Daily use
Buffers
Blood
Inside muscle
Claimed, mixed evidence
Evidence
Strong
Strong
Mixed
Main risk
GI distress
Tingles, missed loading
Overpaying for the lactate story
Best for
Race day
Training blocks
Daily consistency, no GI risk
FAQ
They do different jobs. Bicarbonate is acute and works on race day within hours; beta-alanine is chronic and needs 4+ weeks of daily loading. For efforts of 1-10 minutes the evidence supports both, and they can be stacked.
Yes. They buffer in different compartments (muscle carnosine inside the cell, bicarbonate in the blood), so the mechanisms don't overlap. Trial the combination in training before racing with it.
The evidence says no, at least for the lactate itself: bicarbonate has decades of trials behind it while chronic lactate supplementation failed to improve blood buffering in controlled research. Lactate-based formulas can still earn a place through their electrolyte and taurine content, without bicarbonate's gut risk.