Maurten Bicarb System 19 Review — Race Tested

Maurten System is an expensive delivery mechanism of a cheap but effective performance enhancer. Its biggest selling point is that it significantly reduces the risk of the potentially catastrophic GID effects of sodium bicarbonate ingestion.

System 19 has 4 servings per box, with 8 sachets; 2 are required per serving. At about $/£60 per box, that is $/£15 per serving – that’s one test and three races. Expensive.

Q: Does it work?

A: Yes. I got the Maurten System as a Christmas present and tried it out recently in race conditions. Test results below!

The delivery mechanism

You are paying for the delivery mechanism – a gel plus small tablets. Here’s how it works.

Maurten’s hydrogel technology forms a pH-sensitive alginate-pectin barrier that shields bicarbonate from gastric acid, preventing gastrointestinal distress. This protective transport shuttle bypasses the stomach, delivering bicarbonate directly to the intestine for optimal absorption.

Bicarbonate is compressed into many 3 mm-diameter mini-tablets to minimise surface area exposure in the stomach, thus enabling rapid gastric emptying and avoiding trapping issues of larger capsules. Once in the intestine, the tablets dissolve gradually for controlled release and smoother, sustained performance benefits.

The performance mechanism

Taking baking soda raises blood alkali levels. The effect is to neutralise the acid (H+ ions) that builds up in the blood during hard exercise. Muscles can then quickly push out acid and lactate, so they remain less acidic and continue to contract strongly. This results in better performance in short, intense efforts.

Scientific Citations

• Grgic, J., et al. (2021). International Society of Sports Nutrition position stand: sodium bicarbonate and exercise performance. J Int Soc Sports Nutr.
• Hilton, N. P., et al. (2020). A Proposed Method for the Assessment of Sodium Bicarbonate Efficacy. Front. Nutr.
• Gough, L. A., et al. (2021). Sodium bicarbonate supplementation and individual responses. Eur J Appl Physiol.

Suitable Sporting Uses

The Maurten system is only suitable for sports where you are exercising above the lactate threshold (shorter efforts where your legs might feel like they are burning). Science says it works for about 30 minutes, making it suitable for running distances up to 10k or any other equivalent sport.

Some studies suggest it might be suitable for one-hour time trials, while others state it remains effective for 3-4 hours. Thus, I’m not entirely clear whether and how Maurten’s delayed delivery mechanism might extend the effective period beyond 30 or 60 minutes.

My test, below, was for a demanding multi-sport race of just over an hour.

Maurten Doses, duration and durations

You can have up to 2 servings a week, and at most 1 per day. No loading strategy is required, but you are advised to test its effect on your digestion before race day.

Take 60-90 minutes before your race.

Other Ingredients

The Maurten System is also a fuel and an electrolyte source. Note that one serving also contains

• 5.2g sodium (226% RDA/DV)
• 161 calories
• 39.2g carbs (of which 14.3g dual sugars – Maltodextrin fructose. Maltodextrin is commonly used and similar to glucose froma sports perspective)
• 0.4g saturated fat (2% RDA/DV)

So this does provide a glucose/fructose dual source, but in small quantities. That said, the quantities are probably applicable to 30-minute efforts.

Preparation & Consumption

Maurten will send you a free measuring-and-shaking container. You’ll also need a spoon and some water.

1. Add 200ml of water (to the line)
2. Add sachet B
3. Shake well, leave for 5 minutes
4. Add sachet C
5. Stir gently
6. Ingest immediately
7. Do not chew at all

What other supplements are compatible?

I used other supplements as normal and believe there is no specific advice on complementary supplements from Maurten.

Other than adjusting for the nutritional ingredients, I can’t see how this would impact anything else commonly taken for races.

I used Maurten Gel 100 alongside System in my race, and both worked fine. (They don’t sponsor the article, nor do I have freebies!). I also took Beet-It, caffeine, creatine, beta-alanine and CurraNZ.

Race-Tested

I’ve used regular sodium bicarbonate (baking soda) on and off for years. I have occasionally made mistakes and taken too much, luckily not for important events. Consequently, I tend to err on the cautious side and take relatively small quantities, which may not have much effect. There is sometimes a slight stomach grumbling when I take it, but all is usually Ok.

That said, I believe that it has some positive performance effect for me on shorter distance races – 5k, 10k, and sprint multisport events.

In a recent 2026 race, I took a serving of Maurten ninety minutes before the start.

Here’s what I found

• Making and consuming the mixture adds 10 minutes of faffing to your pre-race routine. It’s one more thing to plan for and worry about.
• I had zero signs of GID (gastrointestinal distress)
• I felt virtually no signs of lactate onset, if any.
• Toward the end of the race (about 60 minutes), I was extremely fatigued, and my legs started to hurt, but that could have been due to my being at my limit.
• I may have fuelled slightly too early in the race, i.e., my fatigue could have been due to a lack of carbs or just general muscular fatigue.

Bottom Line: This was one of my best race results. I was clear of competition as I finished sure of my place, so I didn’t have to push to the absolute limit (which would have been extremely unpleasant). I don’t attribute any of my success to Maurten, but it probably did help. It certainly didn’t hinder my performance at all.

Q: Would I use it again?

A: Yes. Sparingly. It’s very expensive.

Buying considerations

Cost: $70 (USA), €69.95 (EU), £59.95 (UK)

Buy the System suitable for your weight. Thus, if you weigh 70kg, buy system 19.

• Maurten 12: 55kg or less
• Maurten 15: 56kg – 69kg
• Maurten 19: 70kg – 84kg
• Maurten 22: 85kg – 89kg
• Maurten 25: 90kg or more

Maurten

Bicarb System (and Gels)

$70, £60

€70

+other retailers

Last Updated on 9 March 2026 by the5krunner

the5krunner

tfk is the founder and author of the5krunner, an independent endurance sports technology publication. With 20 years of hands-on testing of GPS watches and wearables, and competing in triathlons at an international age-group level, tfk provides in-depth expert analysis of fitness technology for serious athletes and endurance sport competitors.