The Performance Booster That Could Help You Push Through Fatigue—If Your Stomach Can Handle It
Sodium bicarbonate has been around forever. It’s actually baking soda. Athletes have also been experimenting with it for decades as a legal way to fight the familiar muscle burn you feel during hard efforts.
But lately, bicarb has moved beyond track sessions and heavy lifting and into the distance-running spotlight. Case in point: Sabastian Sawe used Maurten’s Bicarb System as part of his race-morning fueling strategy before smashing the marathon world record with a 1:59:30 finish at the 2026 London Marathon.
That doesn’t mean every runner should start spooning baking soda into a glass of water before their next workout, though. It can seriously mess with your stomach, causing bloating, nausea, vomiting, and other GI issues that can undermine any kind of performance boost.
So what exactly does bicarb do, and is it worth trying and risking the side effects? Here’s what to know about sodium bicarbonate and athletic performance—including the potential benefits and downsides.
What Is Sodium Bicarbonate?
In simple terms, sodium bicarbonate is baking soda—a household staple that many of us use to make cookies and cakes, tamp down stinky fridge odors, and clean various surfaces. When taken for athletic performance, sodium bicarbonate is often ingested in a capsule form or by drinking the powder mixed with water, and sometimes other flavors to mask its bitter taste.
The Maurten Bicarb System, the popular bicarb delivery method for athletes, offers sodium bicarbonate in the form of mini tablets. The product also includes a water-based gel. So when you order the product, you receive the hydrogel component, the bicarbonate component, and a mixing bowl so you can combine them.
How Can Bicarb Boost Performance?
Decades of research support the idea that taking specific doses of sodium bicarbonate before certain types of workouts can improve athletic performance. In fact, the International Olympic Committee recognizes sodium bicarbonate as one of five legal supplements “with good to strong evidence” of performance benefits in specific scenarios. (The other four substances include caffeine, creatine, nitrate, and “possibly” beta-alanine.)
A 2021 review published by the International Society of Sports Nutrition (ISSN) concluded that ingesting sodium bicarbonate can boost performance across a number of different workouts, including combat sports, muscular endurance activities, and high-intensity bouts of cycling, running, swimming, and rowing. The benefits of sodium bicarbonate are most established for high-intensity bursts of exercise lasting between 30 seconds and 12 minutes, per the ISSN.
So how, exactly, can sodium bicarbonate enhance your workout? Put simply, it helps enhance your blood’s ability to maintain optimal pH levels during anaerobic exercise (basically, any form of high-intensity exercise that lasts between 30 seconds and several minutes). When you perform anaerobic exercise, your muscle cells rapidly produce hydrogen ions that can accumulate within your muscle cells. These hydrogen ions lower the pH of your cells, making them more acidic.
To reduce this acidity, your cells attempt to buffer against this hydrogen ion accumulation. One buffering process is to push some of the hydrogen ions into your blood, where your body then uses its own natural supply of sodium bicarbonate to combat acidity while maintaining a normal blood pH range, Fabio Comana, faculty lecturer at San Diego State University and master instructor for the National Academy of Sports Medicine, tells Runner’s World.
Thing is, your body only has so much sodium bicarbonate available, so once the supply runs low, your blood stops accepting hydrogen ions from your muscle cells. As a result, they build up in your muscles, causing that burning, achy feeling we all know too well. This is your body’s way of telling you to slow down or stop exercising altogether so that it can have a chance to regenerate its sodium bicarbonate supply, Comana explains.
By taking sodium bicarbonate as a supplement before your workout, you can increase the amount of this compound in your blood and therefore be able to tolerate more hydrogen spillover before your muscles yell at you to stop, says Comana. In other words, you’ll be able to perform at a higher intensity and/or for a longer period of time before having to take a break.
The benefits of sodium bicarbonate are most proven to help athletes who participate in anaerobic-based events like sprinting or heavy lifting. That said, people who partake in endurance events, like steady-state running or cycling, could still get some boost from taking sodium bicarbonate if their event includes sprints during or at the end of the competition, per the ISSN. So, runners participating in a sit-and-kick 5K or 10K could see some perks to taking sodium bicarbonate.
However, bicarb research is beginning to expand to long-distance events—and following Sawe’s history-defining outing, will likely continue to do so. For example, a study published in the European Journal of Applied Physiology in 2024 conducted on 14 trained cyclists shows that after ingesting the Maurten Bicarb System, athletes increased their 40-kilometer time trial by 1.42 percent (more than 54 seconds was the mean outcome), compared to their times with no intervention.
What Are the Side Effects of Sodium Bicarbonate?
Here’s the thing: Ingesting sodium bicarbonate can lead to a number of GI issues, including bloating, nausea, vomiting, and abdominal distress, says Comana. Indeed, the ISSN lists these as the most common side effects of sodium bicarbonate supplementation and notes that they can harm exercise performance.
These side effects arise because sodium bicarbonate is alkaline and so when you put it into your stomach, which is very acidic, your body reacts by producing more gastric acid. This results in a release of gases that leads to those unpleasant side effects, explains Comana, who speaks from firsthand experience.
He’s taken sodium bicarbonate before a workout three separate times. “I didn’t want to throw up, but I just didn’t feel right, I just didn’t feel good,” he recalls. “My general perceptions of it were, yeah, this wasn’t too much fun.” But, he adds, “for every one of me, there’s probably others that had no effect and they loved it.” Indeed, per the ISSN, the incidence and severity of sodium bicarbonate side effects “varies between and within individuals, but it is generally low.”
If sodium bicarbonate messes with your stomach, you can try prolonging the period during which you consume it as a way to reduce the risk of GI upset, registered dietitian Marisa Michael, RDN, CSSD, board-certified specialist in sports dietetics, tells Runner’s World. “Sip it mixed with water slowly over two to three hours before your event, rather than drinking it quickly immediately beforehand,” she advises.
Additionally, a 2011 study involving 13 athletes concluded that ingesting sodium bicarbonate along with a carb-rich meal could reduce GI symptoms.
What Makes Maurten’s Product Stand Out?
The Maurten Bicarb System promises to deliver the performance benefits of sodium bicarbonate while reducing the risk of GI issues. That’s because the product is formulated to stay intact in the stomach—thus bypassing that acidic environment—and only break down once it reaches the small intestine, Josh Rowe, head of sports tech at Maurten, tells Runner’s World.
Essentially, the hydrogel creates a protective structure around the mini tablets of sodium bicarbonate to prevent them from breaking down in the stomach. Additionally, the small diameter of the tablets helps them pass easily through the stomach and reach the small intestine still intact, Rowe explains.
Internal testing with employees and Maurten athletes—including ultrarunner Killian Journet, who consumed the product during a 100-mile race in Sweden as well as the Ultra-Trail du Mont-Blanc, and Olympic speed skater Nils van der Poel, who used it during the 2021–2022 season—suggest the formulation has proven successful at boosting performance while quashing GI issues. Sawe is another example, as well as Runner’s World senior news editor, Theo Kahler.
What Should You Know Before Taking Sodium Bicarbonate?
Curious to try sodium bicarbonate yourself? Start with a small dose, suggests Comana. “It’s a good idea to wean yourself onto it,” he says. “Don’t just dive into a big dose because you may get the side effects.”
The ISSN recommends taking between 0.2 and 0.3 grams of sodium bicarbonate per kilogram of bodyweight as a single dose about one to three hours before a workout or competition. So, a 165-pound athlete would aim to ingest 15 to 22 grams prior to their event.
That said, you may consider starting with a smaller dose—say, 0.1 grams per kilogram of bodyweight—and “see how that feels,” says Comana. Though any amount less than 0.2 grams per kilogram has not been proven to enhance performance, per the ISSN, starting with a low amount could help you ease into sodium bicarbonate consumption while minimizing your risk of side effects. If you tolerate it okay, then you can try upping your dosage, says Comana.
Another approach is to gradually load up on smaller doses of sodium bicarbonate for multiple days before your big workout or competition, per ISSN. This can reduce the risk of side effects during your event. Instead of taking just one dose of sodium bicarbonate the day of your workout, you’d consume 0.4 or 0.5 grams per kilogram per day for three to seven days prior to race day. You’d break these daily doses into smaller amounts throughout each day—say, 0.1 to 0.2 grams per kilogram taken at each meal.
However you choose to ingest sodium bicarbonate, avoid adopting the mindset of “more is better,” says Comana. Research points to 0.3 grams per kilogram as being the optimal one-time dose for performance benefits, per the ISSN. Down any more than that, and you may just end up with intensified side effects without any additional performance benefit, Comana warns.
If you try Maurten’s product, follow the use instructions provided with the product, as they differ slightly from the ISSA recommendations.
When considering whether sodium bicarbonate is worth a try, take stock of whether you want to devote the time and mental energy to implement it, whether you need a performance enhancer, and if you are doing an event where it could be helpful, says Michael. “The average weekend warrior marathoner may not need this. A sprinter may benefit from it,” she says.
Lastly, be aware that sodium bicarbonate, as the name suggests, does contain sodium, says Michael. Depending on factors like your blood pressure, sweat rate, and current diet, this product may not be safe to take daily. “Always check with your healthcare provider before undergoing a diet or supplement change,” Michael advises.
The Bottom Line on Bicarb
If you’re able to stomach sodium bicarbonate (pun intended), it “would be a very viable supplement to take before those intense workouts,” says Comana, such as hill repeats, speed intervals, or a heavy weightlifting session.
But it may not be worth it for every athlete. “As with any nutritional intervention, it takes some dedicated time, mental energy, and cost to implement,” says Michael. “You can decide if this is worth it for you to try. If it feels overwhelming or not worth the effort, then it probably isn’t.”
Jenny is a Boulder, Colorado-based health and fitness journalist. She’s been freelancing for Runner’s World since 2015 and especially loves to write human interest profiles, in-depth service pieces and stories that explore the intersection of exercise and mental health. Her work has also been published by SELF, Men’s Journal, and Condé Nast Traveler, among other outlets. When she’s not running or writing, Jenny enjoys coaching youth swimming, rereading Harry Potter, and buying too many houseplants.