Sodium bicarbonate, the same compound as baking soda, can improve performance in hard efforts lasting roughly 30 seconds to 12 minutes. Think 800 m to 1,500 m running, 2,000 m rowing, 100 to 400 m swimming, high-intensity cycling and combat sports. The research-backed single dose is 0.3 g per kilogram of body mass, taken 60 to 180 minutes before you start. The main thing to manage is stomach upset, and that comes down to dose, timing and what you eat with it. Below you will find the evidence, the dose math, a timing plan and the safety points that matter.
Key Takeaways
- Bicarbonate works best for high-intensity efforts of about 30 seconds to 12 minutes, where acid buildup in the muscle limits you. It does little for easy, long aerobic work.
- The single-dose standard is 0.3 g/kg of body mass, with 0.2 g/kg as the minimum effective dose. Going to 0.4 or 0.5 g/kg adds side effects, not extra benefit.
- Take it 60 to 180 minutes before exercise, ideally with a carbohydrate-rich meal. Waiting closer to 180 minutes tends to mean less stomach discomfort.
- Bloating, nausea and abdominal pain are the common side effects. Rehearse your plan in training, never for the first time on race day.
- It adds a real sodium load, so people with kidney disease or on sodium-restricted diets should talk with their doctor first.
Table of Contents
- What sodium bicarbonate does during hard exercise
- Which events and athletes benefit
- How much sodium bicarbonate to take: the dose math
- When to take it before a workout or race
- Side effects and how to reduce them
- Is it allowed in competition?
- Putting bicarbonate in a wider performance plan
- Where Fitnesshealth fits
- Our perspective
- FAQ
- Sources
What sodium bicarbonate does during hard exercise
When you sprint, row or ride at the limit, your muscles produce hydrogen ions faster than they can clear them. That acid buildup is considered a primary contributor to fatigue during high-intensity work. Sodium bicarbonate is an alkalizing agent. According to a 2026 review in the Journal of the International Society of Sports Nutrition, swallowing it raises the bicarbonate concentration in your blood, and rises of about 5 mmol/L are typically linked to the performance benefit.
The same review explains the next step. Muscle cell membranes do not let bicarbonate through, so a higher level in the blood widens the pH gradient between the inside and outside of the muscle cell. That gradient helps move lactate and hydrogen ions out of working muscle fibers, which delays the point where fatigue forces you to slow down.
In plain terms: you are not adding fuel. You are giving your body a bigger buffer, so you can hold a hard pace a little longer.
Possible benefits beyond buffering
A 2024 narrative review by Gurton and colleagues suggests the mechanisms may reach past simple blood pH. Changes in strong ion difference and a calmer cellular stress response may also help recovery between hard bouts. That matters for athletes who race heats and finals on the same day, or train twice a day. Recovery between sessions also depends on everyday habits, such as foam rolling for muscle soreness, sleep and food.
Which events and athletes benefit
The International Society of Sports Nutrition (ISSN) 2021 position stand concludes that doses from 0.2 to 0.5 g/kg improve performance in muscular endurance activities, combat sports (boxing, judo, karate, taekwondo, wrestling), and high-intensity cycling, running, swimming and rowing. The effect is mostly established for tasks lasting between 30 seconds and 12 minutes, and it appears in both men and women.
The Australian Institute of Sport (AIS) describes good evidence for athletes competing in high-intensity activity of 1 to 7 minutes, such as swimming, rowing and middle-distance running.
The 2026 review lists specific tasks where improvements have been recorded:
- 4 km, 16.1 km and 40 km cycling time trials
- 2 km rowing
- 400 m and 1,500 m running, plus 800 m, 1,500 m and 3.5 km time trials
It also notes that the size of the benefit depends on the physiological demands of each sport.
How big is the gain?
Small, but meaningful in sport. A 2016 meta-analysis summarized by Siegler and colleagues reported roughly 2 to 3% improvement across measures such as power, speed, work capacity and time to failure. A 2013 systematic review in the Journal of Strength and Conditioning Research cites an estimate that 0.3 g/kg would lift mean power in a 1-minute sprint by 1.7%. The same review found a mean 1.5% improvement for running distances between 400 m and 40 km.
A 2021 umbrella review by Grgic and colleagues found that bicarbonate acutely enhances peak anaerobic power, anaerobic capacity, muscle endurance, 2,000 m rowing and high-intensity intermittent running. Its authors also note that more research in women would improve how widely the results apply.
Think of a 1.5% gain in a 4-minute effort: about 3.6 seconds. In a race decided by fractions, that is a lot.
Who sees the most from it
Responses vary by person and by sport. A systematic review by Peart and colleagues found a moderate overall effect, with a smaller effect in specifically trained athletes than in recreationally trained participants. The practical lesson is that your own response matters most, which is why a trial run in training is built into every protocol below.
How much sodium bicarbonate to take: the dose math
Dosing is by body mass. The ISSN position stand sets out the numbers:
- Minimum effective single dose: 0.2 g/kg
- Optimal single dose: 0.3 g/kg
- Higher doses (0.4 or 0.5 g/kg): no added benefit over 0.3 g/kg in single-dose protocols, and a higher incidence and severity of side effects
Here is what that looks like in grams:
| Body mass | 0.2 g/kg | 0.3 g/kg (optimal) | 0.5 g/kg |
|---|---|---|---|
| 55 kg (121 lb) | 11 g | 16.5 g | 27.5 g |
| 70 kg (154 lb) | 14 g | 21 g | 35 g |
| 85 kg (187 lb) | 17 g | 25.5 g | 42.5 g |
To convert pounds to kilograms, divide by 2.2. Weigh your dose on a kitchen scale instead of using spoons. Side effects rise in a straight line with the dose, so accuracy protects your stomach.
If your plan uses capsules, check the label for the amount of sodium bicarbonate per capsule, then work out how many you need to reach your target. Enteric-coated capsules are one of the strategies the ISSN lists for reducing the likelihood and severity of gut symptoms.
When to take it before a workout or race
The single-dose plan
The ISSN recommends taking a single dose between 60 and 180 minutes before exercise or competition. The AIS recommends 200 to 400 mg/kg with a small, carbohydrate-dense meal (about 1.5 g/kg of carbohydrate) roughly 120 to 150 minutes beforehand. It adds that higher doses taken 2 to 3 hours out should raise blood buffering by about 5 to 6 mmol/L, with effects lasting 3 to 4 hours.
The 2013 JSCR review points to 0.3 g/kg with a high-carbohydrate meal and 7 mL/kg of flavored water, 2 to 2.5 hours before competition, as the combination most likely to optimize buffering with the least risk of gut trouble.
On timing, one study on ingestion timing found that blood buffering and ergogenic potential did not change with timing, but people were less prone to significant stomach discomfort 180 minutes after taking it. If you are unsure, start at the later end of the window. The World Athletics statement says peak blood bicarbonate arrives 75 to 180 minutes after a 0.3 g/kg dose and begins to fall by 3 hours, so do not take it so early that the window closes before you start.
Worked example: a 70 kg 1,500 m runner
- Race at 2:00 pm. Plan to take the dose around 11:30 am to 12:00 pm.
- Weigh out 21 g (0.3 g/kg).
- Eat a small, carbohydrate-heavy meal at the same time, such as rice or toast with jam.
- Drink about 490 mL of flavored water (7 mL/kg) with it.
- Warm up as normal and note how your stomach feels, then adjust next time.
The multi-day plan
For athletes who react badly to a single large dose, the ISSN describes loading over 3 to 7 days before the event. The total is 0.4 or 0.5 g/kg per day, split into smaller doses of 0.1 to 0.2 g/kg at breakfast, lunch and dinner. For a 70 kg athlete, that is 7 to 14 g per meal. This approach can improve performance and lower the risk of side effects on competition day. The World Athletics statement likewise notes that split doses or serial loading over 2 to 4 days have been proposed to overcome gut distress.
Repeated bouts and recovery gaps
Gurton and colleagues found that 0.3 g/kg taken about 60 to 90 minutes before exercise is the most common strategy in research. Recovery gaps of 30 to 90 minutes between bouts seem best for getting the benefit. If you have only 30 minutes or less between efforts, a benefit is unlikely. They also describe “top-up” doses as a new area that could suit endurance athletes.
Side effects and how to reduce them
The most common side effects are bloating, nausea, vomiting and abdominal pain, caused by carbon dioxide building up in the gut. USADA also lists diarrhea and notes that for some individuals the effects can hurt performance, so the benefit depends on the athlete, the dose and the specific exercise.
In a 2025 meta-analysis of single-dose studies, GI symptoms occurred in 29.5% of bicarbonate trials versus 2.6% with placebo. That figure is the reason a careful protocol matters. The ISSN position stand offers practical ways to cut risk:
- Use the smaller effective doses (0.2 or 0.3 g/kg) rather than 0.4 to 0.5 g/kg
- Take it closer to 180 minutes before exercise, or adjust timing to your own response
- Take it with a high-carbohydrate meal
- Use enteric-coated capsules
- Consider the multi-day split-dose plan
The World Athletics statement stresses that any supplement should be thoroughly trialed in training before competition. Run at least two or three practice sessions with the exact dose, meal and timing, and write down how you felt.
Sodium load and who should check with a doctor first
Bicarbonate is a sodium salt. According to the ISSN, long-term use at common doses (0.3 g/kg) raises your habitual sodium load, which may push intake past the Tolerable Upper Intake Level in dietary guidelines. The effects on kidney function are not yet known. The Academy of Nutrition and Dietetics 2020 chronic kidney disease guideline advises adults with CKD stages 3 to 5 who are not on dialysis to keep sodium under 2.3 g per day.
If you have kidney disease, high blood pressure, heart conditions, or have been told to restrict sodium, talk to your doctor before trying bicarbonate. Our guide to sodium intake for athletes helps you see where your daily total sits. If you train long and hot, also read about when to take electrolytes so your sodium plan is deliberate.
Is it allowed in competition?
USADA states that oral buffer supplements, including pills and tablets with sodium bicarbonate or sodium citrate, are not prohibited under the WADA Prohibited List. Intravenous infusions or injections above 100 mL total per 12-hour period are strictly prohibited. USADA also reminds athletes that supplements are used at their own risk and that anti-doping status should be checked for anything taken. If you compete under anti-doping rules, confirm the current status with your governing body before race day.
Putting bicarbonate in a wider performance plan
Bicarbonate targets one limiter: acid buildup in hard efforts. It sits alongside other levers, and it is worth knowing which problem each one solves:
- Sprint capacity: see how creatine and beta-alanine compare for sprint times.
- Long events: our rundown of the best supplements for endurance covers what to build around the buffering work.
- Race-day choices: performance supplements for competition lays out how serious athletes select and test what they use.
- Breathing and CO2 tolerance: building CO2 tolerance is a related piece of the acid-base puzzle for endurance athletes.
A sensible order: get your training, sleep and carbohydrate intake right first, then add one change at a time so you can see what works.
Where Fitnesshealth fits
If you are building a performance routine around hard training, our collections cover Strength & Fitness, Energy, Vitamins & Minerals, Sleep and Joint Health, among others. Our site pairs the products with educational guides so you can match what you buy to your event and goal. Browse the full collections or go straight to Vitamins & Minerals.
We publish our own guides on sodium, electrolytes and competition supplements so that the choices you make are informed ones, and our positioning rests on in-house quality testing and a scientific basis for formulations.
Our perspective
Athletes ask us about bicarbonate because it is one of the few ideas in sports nutrition with a clear mechanism and dosing that is built on body weight. That precision is the useful part. A 0.3 g/kg dose, a meal, a timing window and a few practice runs turn a vague hope into a plan you can repeat.
Our view is that performance is built from small, well-chosen decisions. Quality-tested products, clear information and a routine you have rehearsed matter more than any single trick. That is why we pair what we sell with guides on sodium, electrolytes, recovery and event-specific choices.
If you plan to compete, write your protocol down, trial it in training, and change one variable at a time. Then bring the same discipline to the rest of your supplement routine, from minerals to sleep support.
Rene Harwood
FAQ
How much sodium bicarbonate should I take for athletic performance?
The ISSN identifies 0.2 g/kg as the minimum effective single dose and 0.3 g/kg as the optimal one. For a 70 kg athlete, that is 14 g and 21 g. Higher single doses of 0.4 to 0.5 g/kg do not add benefit and increase side effects.
Is baking soda the same as sodium bicarbonate for a pre-workout?
Yes, baking soda is sodium bicarbonate. The research uses it by weight, 0.3 g/kg in the typical protocol, taken 60 to 180 minutes before exercise with a carbohydrate-rich meal. Weigh it rather than guessing with spoons, and use enteric-coated capsules if the taste or your stomach is an issue.
What are the side effects of sodium bicarbonate?
Bloating, nausea, vomiting, abdominal pain and sometimes diarrhea are the most common, and they rise with the dose. Smaller doses, a carbohydrate meal, taking it nearer 180 minutes before exercise and enteric-coated capsules can reduce them. Anyone with kidney disease or on a sodium-restricted diet should speak with a doctor first.
Does sodium bicarbonate help you run faster?
It has improved performance in field studies at 400 m, 800 m and 1,500 m, and the 2013 JSCR review found a mean 1.5% improvement across running distances from 400 m to 40 km. Individual response varies, and gut symptoms can affect race times, so trial your plan in training first.
Is sodium bicarbonate banned in sport?
Oral sodium bicarbonate supplements are not prohibited under the WADA Prohibited List, according to USADA. Intravenous use above 100 mL per 12 hours is prohibited. Check the current rules with your governing body if you compete under anti-doping programs.
Sources
- International Society of Sports Nutrition position stand on sodium bicarbonate (2021)
- Common questions and misconceptions of sodium bicarbonate supplementation (2026)
- AIS: How and when do I use bicarbonate
- Effects of sodium bicarbonate supplementation on exercise performance: umbrella review (2021)
- Mechanistic insights into the efficacy of sodium bicarbonate (2016)
- A systematic review of the efficacy of ergogenic aids for running (JSCR, 2013)
- Practical recommendations for coaches and athletes (Peart et al.)
- Sodium bicarbonate supplementation and ingestion timing
- Enhancing exercise performance and recovery through sodium bicarbonate (2024)
- Negligible benefit of oral single-dose sodium bicarbonate on running (2025)
- USADA: What athletes should know about sodium bicarbonate
