Basketball players swallowed about 38 g of baking soda a day for four weeks and jumped higher than those on the usual dose. Nobody tested their blood, and not one reported a stomach ache

Sodium bicarbonate, the baking soda in the kitchen cupboard, is one of the oldest legal performance aids in sport. Hard sprinting floods muscle with acid, bicarbonate in the blood mops some of it up, and athletes who load up beforehand can often hold a flat-out effort a little longer. The usual dose is 0.3 g for every kilo of body weight. A trial published on 9 October 2026 in the Journal of the International Society of Sports Nutrition asked what happens if players take half as much again, every day, through a month of training.

Two researchers at universities in Huzhou and Ningbo recruited 40 male club basketball players, average age about 22, and split them at random into four groups of ten. Three groups added sprint sessions to their normal practice three times a week: four sets of ten all-out five-second sprints. One of those groups took 0.3 g per kilo of bicarbonate a day, one took 0.45 g per kilo, and one took maltodextrin as a placebo. The fourth group just carried on with basketball.

The daily amount was split into five servings, at 8 am, noon, 4 pm, 8 pm and midnight, in opaque capsules. For a player of average weight in the high-dose group, 0.45 g per kilo works out at about 38 g a day, or roughly 7.6 g each time. The paper says players took 'about five' of the largest standard capsules per serving.

After four weeks, everyone who sprinted had improved and the basketball-only group had not. Among the sprinters the order was the same on every test: high dose first, standard dose second, placebo third. Vertical jump rose by 2.5 cm on the high dose, 1.7 cm on the standard dose and 1.1 cm on placebo. On the Yo-Yo shuttle test, the three groups ran 170, 122 and 76 metres further than before. The 20-metre sprint got faster by 0.17, 0.12 and 0.08 of a second.

The final tests were run 72 hours after the last capsule, so the bicarbonate itself should have left the blood. The claim, then, is that the players had trained themselves into better shape, perhaps because the buffer let them push harder in each session. That fits a line in the sports nutrition society's own 2021 position paper, which says long-term use before training 'may enhance training adaptations'.

Here is what the trial did not do. Nobody took blood. There are no readings of bicarbonate, acidity or lactate, so there is no evidence the capsules changed anything in the players' bodies, let alone that the bigger dose changed more. Nor is there any record of how hard each man actually sprinted in training. The authors say all this themselves and call their result 'suggestive of a possible additive effect rather than definitive evidence'.

Then there is the stomach. Bicarbonate is known for bloating, nausea and worse, and the 2021 position paper says doses of 0.4 or 0.5 g per kilo bring more of it than 0.3. In this trial, 20 men took 25 to 38 g a day and not one complaint was recorded. The way complaints were collected was to ask at training sessions. The authors admit no proper symptom questionnaire was used and that mild trouble may have gone unreported. Splitting the dose five ways may well have helped. It is still a surprising zero.

One thing the paper leaves out entirely is the sodium. A little over a quarter of sodium bicarbonate by weight is sodium, so 38 g of it carries about 10 g. The World Health Organization advises adults to stay under 2 g of sodium a day from all food. Four weeks at five times that, on top of normal meals, in young fit men, may do no harm. The trial did not measure blood pressure or anything else that would tell us, and the words do not appear in the paper.

So this is a small, short study with a tidy result and thin checks, in young male players only. Its own conclusion suggests coaches could use the higher dose in a four-week pre-season. That is further than ten men per group can carry. For anyone with high blood pressure, kidney or heart trouble, or a doctor's instruction to watch their salt, large doses of baking soda are not a training experiment to try at home.