What is sodium bicarb?
Sodium bicarbonate is simply baking soda, the same product that many people keep in their kitchen cupboards. Athletes can use it in capsule form or as plain baking soda mixed into fluid. One gram of sodium bicarbonate contains about 270 milligrams of sodium. For context, many people aim to keep daily sodium intake under roughly 2000 to 2300 milligrams of sodium per day, so supplement doses can contribute a meaningful amount.
Proposed mechanism
During hard exercise, muscles produce extra hydrogen ions, which lowers pH and contributes to fatigue. Taking sodium bicarbonate raises extracellular bicarbonate levels, helping remove these ions. This helps maintain pH, supports higher energy production, and can delay fatigue so athletes hold higher power for longer.
A simple way to view it is that sodium bicarbonate helps when you feel that “lactic acid” style burn. It seems most useful for all-out efforts lasting roughly 30 seconds to about 12 minutes. Think 400 metre runs or short endurance pieces under about eight to twelve minutes, as well as many CrossFit-style events where athletes “send it” the whole time.
Because these efforts rely heavily on anaerobic glycolysis, sodium bicarbonate can buffer that build-up and support performance. Track athletes, cyclists, rowers, swimmers, combat sport athletes, and team sport players doing repeated sprints may all fit this profile. In some ball sports, players may hold a little back due to the skill demands, so the fit is not always as clear as in pure all-out efforts.
How to take – doses, timing
For performance, most people use 0.2–0.4 g per kg of body weight, taken with carbs and fluids two to three hours before exercise. For an 80 kg athlete, that is around 24 g of sodium bicarbonate.
Capsules can be impractical here. If each capsule has about one gram, that same athlete would need roughly 24 capsules, so some people use straight baking soda mixed with water instead and then have a carb snack or drink. The taste can be unpleasant, which is worth considering. Aim to take it with at least 300–500 mL of water, and some people trial splitting the total dose into smaller servings across the day to reduce gut issues.
Sodium content also matters. One gram of sodium bicarbonate has about 270 mg of sodium, so a mid-20 gram dose gives several grams of sodium. Across the whole day, intake can easily exceed 10 g if someone uses large doses regularly with normal food intake. Athletes often tolerate higher sodium and usually have lower cardiovascular risk, but that level still raises mild concern if used often.
Gastrointestinal issues
Gastrointestinal upset is one of the biggest downsides of sodium bicarbonate. Research often reports nausea, stomach pain, diarrhoea, and vomiting in some people, usually 60–90 minutes after taking it, which is often right before competition.
Because of this, testing it in training is essential. Athletes can start with a lower dose in less important sessions and slowly build up if they tolerate it. Taking it with 300–500 mL of water and, for some people, splitting the total dose into smaller servings across the day or over a few days may help. In practice, GI distress can easily outweigh any performance benefit, so planning, trialling, and adjusting dose and timing are crucial.
Anecdotes
Athlete experiences with sodium bicarbonate often sound dramatic. Many report a clear reduction in the “lactic burn” during hard efforts and small but real performance gains, often in the one to three percent range, with some claiming more.
At the same time, those athletes frequently mention that their gut feels terrible. Some describe a real dilemma, like taking it before a 400 metre final, winning, but feeling it was a risky move because of how bad their stomach felt.
Practitioner anecdotes are similar. Beta-alanine can feel like nothing despite strong research, while sodium bicarbonate often creates an immediate change in how that lactic build-up feels, plus a big increase in thirst from the sodium load. That mix of strong perceived benefits and strong side effects shapes how many people view this supplement.
What does research show?
Research shows the biggest benefits in short, intense bouts of exercise. The effects are clearer in repeated high-intensity efforts than in longer endurance events. In simple terms, sodium bicarbonate seems most helpful for hard efforts lasting roughly 30 seconds to 12 minutes.
A meta-analysis found average performance gains of about one to three percent, with some people seeing around five percent. Others saw smaller changes, and some even got worse when gastrointestinal distress kicked in, which shows how side effects can cancel out any benefit. Longer-term work adds to this. In one eight-week program, athletes who took sodium bicarbonate before intervals improved lactate threshold by about 24 percent, compared to about 15 percent in the group doing the same training without it.
Researchers have also compared sodium bicarbonate with beta-alanine. Both buffer pH, but in different places: beta-alanine increases intracellular pH, while sodium bicarbonate raises extracellular pH. Because they act in different compartments, combining them can provide added benefits rather than cancelling each other out. Beta-alanine is often easier to use in practice because it does not cause gut issues, although it can cause paraesthesia in some people.
Performance
Performance research looks at both real races and controlled tests. In one study of national-level 1500 metre runners, athletes who used sodium bicarbonate improved by about four to five seconds compared with placebo. At that level, that is a meaningful edge, even if it is not huge in absolute terms. This kind of result has driven interest in running circles, especially with the idea that pushing harder in intervals might lead to better race performances, which lines up with the eight-week lactate threshold study.
The same principles apply to other sports that involve maximal or near-maximal efforts in the 30-second to 12-minute range. Short track events, cycling, rowing, swimming, combat sports, repeated sprints, and CrossFit may all benefit, since athletes often go close to all-out. Strength research is more mixed. Studies show improvements in muscular endurance, but not in low-rep maximal strength, which makes sense because endurance tests create a more “lactic” environment where pH buffering matters.
Recovery
Evidence for recovery is still emerging. Some people suggest that because sodium bicarbonate helps buffer acid and clear hydrogen ions more quickly, it might support faster recovery between sessions or between efforts. This idea makes sense on paper, yet current research does not provide enough detail to make firm recommendations.
Early work hints that there could be benefits, particularly when athletes use sodium bicarbonate before repeated hard interval sessions over time. However, more studies need to confirm how much it actually improves recovery in different sports and training structures. For now, the clearest evidence remains in acute performance during specific types of efforts rather than in recovery outcomes.
What do we think of this in practice/ recommendations
In practice, sodium bicarbonate is not a go-to supplement for every athlete. It suits a specific group: people competing at a high level in all-out events lasting roughly 30 seconds to 12 minutes, who are chasing that extra one to three percent and are willing to manage the trade-offs.
For those athletes, trialling it in training makes sense. They can start with a lower dose, pair it with a carb snack and plenty of fluid, and test timing two to three hours before hard sessions. If they tolerate it, they can build toward 0.2–0.4 g per kg while keeping an eye on gut symptoms, thirst, and overall comfort.
For many others, the downsides often win. Gut issues are common and can hurt performance more than they help. Bigger doses also add a lot of sodium, which can push daily intake very high if used often. Because of this, sodium bicarbonate is more “worth considering” than “essential” – a useful tool for the right athlete in the right event, as long as they approach it cautiously and weigh the potential gains against the risks.
Relevant Blog Posts
Sodium Bicarbonate As A Sports Supplement? How To Use It
Relevant Studies
The effect of sodium bicarbonate ingestion on 1500-m racing time – PubMed