Sports Science Dudes

Episode 96 - Andy Sparks PhD - Buffering the Limits: The Science of Sodium Bicarbonate

• Jose Antonio PhD

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BIO: Andy Sparks, PhD, was an academic in the UK for ~25 years and is now the Research Innovations Manager for Maurten AB, Sweden, and an Honorary Visiting Research Fellow at Liverpool John Moores University, UK. His research focuses on nutritional interventions to enhance sports performance, particularly the use of sodium bicarbonate. He has published extensively on a range of topics in exercise physiology and sports nutrition, with a particular interest in endurance cycling and running performance.

Dr. Andy Sparks shares his expertise on sodium bicarbonate as an overlooked yet highly effective ergogenic aid for sports performance, with a particular focus on recent advances in delivery methods that minimize gastrointestinal distress. He explains the science behind bicarbonate supplementation and reveals why this supplement deserves more attention from athletes across multiple sports.

Key Points!

• Sodium bicarbonate is recognized as an A-list evidence-based supplement by the Australian Institute of Sport
• Traditional delivery methods caused GI distress, giving the supplement a negative reputation despite its effectiveness
• Works as an extracellular buffer that helps manage hydrogen ions during high-intensity exercise
• May also reduce pain perception during exercise, explaining benefits in longer-duration events
• Effective for high-intensity activities (400m-3000m races), intermittent sports, and even endurance events
• Dosing varies widely (0.1-0.3g/kg bodyweight) with significant inter-individual response variability
• Peak blood bicarbonate levels occur between 15-90 minutes post-ingestion, depending on delivery method
• The Maurten bicarb system combines mini-tablets with a carbohydrate hydrogel to maximize effectiveness while minimizing GI issues
• Safety concerns relate primarily to sodium load rather than bicarbonate itself
• Particularly beneficial for race strategies with high-intensity starts followed by sustained efforts

The Maurten bicarb system is available online at maurten.com, with region-specific sites including a US option.


Dr Antonio:

Welcome to the Sports Science News. I'm your host, dr Jose Antonio, and today my special guest is Dr Andy Sparks. He was an academic in the UK for about 25 years and is now the Research Innovations Manager for Martin AB Sweden and an Honorary Visiting Research Fellow at Liverpool John Moores University in the UK. His research is focused on nutritional interventions for enhancing sports performance, particularly the use of sodium bicarbonate. He's also published widely on variety of topics across exercise physiology, sports nutrition, and is especially interested in endurance, cycling and running performance. So, dr Sparks, I want to welcome you to the podcast. Appreciate your time, yeah thanks for the invite.

Dr Antonio:

Now I've always been interested in the sports nutrition, sports supplement category and if you were to just randomly ask 10 people who do research in this category what are their top five, you know most, I guess, the most effective or the ones they would most recommend. What's interesting is sodium bicarb actually is hardly ever mentioned, and it might be because, as you're well aware, people who've tried it say they get GI distress. So in a way it's almost been dismissed, despite the fact that it actually works pretty well when you use it correctly. So first the pragmatic question what would be the types of sports or activities that would likely benefit the most from sodium bicarb? And also talk about the dosing and why it was such an issue up until now.

Dr Sparks:

Yeah, you're right, it's been very much sort of overlooked in a way, partly because of those sort of side effects.

Dr Sparks:

But I think if you look at things like the Australian Institute of Sports list of what they think are A-listed evidence-based supplements or ergogenic aids, evidence-based um supplements or um ergogenic aids, um bicarbonate is front and center there.

Dr Sparks:

We know that an awful lot of athletes use it across multiple sports. It's just that until fairly recently, some of the gi problems have kind of put people off, and it's almost, I guess, the reputation of the supplement which has reduced the its uptake with with athletes, because some of them certainly that I've come across in the past will literally say I'm not taking that because it might give me problems, right, even though we, you know we always have that mantra don't, we have, don't do anything new in a competition, always try things in training. That's not always the case, but I think one of the major things, though, is that reputational issue has kind of prevented people from doing it, and I think that's one thing, and especially if you're looking at sort of intermittent sports in particular, where there are body contacts, you really don't want a set of GI problems in those sorts of instances. So you know, contact sports like football, rugby, those type of field sports or the mixed martial arts.

Dr Sparks:

Yeah mixed martial arts, taekwondo there's actually quite a number of papers on taekwondo and wrestling using bicarbonate protocols. They tend to use multiple ingestion points with fairly low doses, so maybe 0.1 or 0.2 grams per kilo per dose, and then load that for a few days prior to competition. But, like I said, for the majority of people that has previously been something of a no-go zone. People have just thought, no, I'm not going to do that. And most people who have messed with bicarbonate in its traditional delivery systems liquid or capsules they will have heard of somebody or know somebody who's had a really torrid time having taken, having taken a liquid dose in particular, which is we always use the phrase or as you use the phrase lively, and it certainly can be. That's not something that you really want to do pre-competition.

Dr Sparks:

So one of the things that we did in our research work was to mess about with ways of sort of circumventing some of those GI issues and we used capsules using sort of pharmaceutical coatings that are designed to bypass or stop interactions of drugs actually with stomach acid and so by you, by reducing the interaction, you certainly alleviate some of the upper GI problems. The major GI problem is caused with the interaction of sodium bicarbonate with stomach acid and it produces CO2 and that causes bloating and bad gas. So that's, again, not particularly useful, especially for doing something like cycling, where actually there's a reasonable amount, a pressure on your stomach whilst you're bent over in a time trial position. That could be uncomfortable potentially. And of course, the other thing is if you're, if you're having those interactions, you're losing some of the bicarbonate you're delivering anyway because it's being just converted into co2, or at least some of it.

Dr Sparks:

So, uh, so that's part of the issue really, I think. And then, if you look in the literature, there is a real mixed bag, whilst predominantly the vast majority of protocols show that there's an ergogenic effect. There is a lot of noise out there, and I think some of that noise is also to do with different dosing timings, dosing ingestion types, but then also the noise associated with. You know, a good proportion of the population included in the study doesn't feel very good.

Dr Antonio:

Let me ask you this so if we were to take, you know, one of the simpler sports and I try to use track as an example, because everyone knows the distances, you know the one to two to four, because everyone knows the distances, you know the one to two to four, eight which of those distances I guess you would start with the 400, would be most benefited from using sodium bicarb? I guess, comparing the 800 to 15 or the mile, and then going up to the 3000 and 5000, or would they all?

Dr Antonio:

benefit just to different degrees.

Dr Sparks:

Yeah, I think if you look at the traditional view of how bicarbonate likely works, that I think has also limited the sort of focus of what people have used it for. And then what studies have been actually done. There has been some longer duration studies, but they again seem to have just been overlooked in the literature. So many people just didn't really get hold of those studies and go okay, well, this is really interesting. There's some ergogenic effects for exercise of an hour or more. Let's try and explore that. But it, you know, whilst those some of those studies there, they did get overlooked.

Dr Sparks:

So, but if you look at the sort of traditional view of things from a bicarbogenics perspective, it's really about hydrogen ion buffering and dealing with sessions which are really intense and either repeated in nature or they're just, you know, around a minute or, if you look at recent meta-analyses, up to about 10 or 12 minutes or so. They're the things based on that sort of energy pathway that's most likely to benefit. But in reality we know that it works on a multifactorial level. It's not just about dealing with hydrogen ions because there's another effect. Know, dealing with hydrogen ions because there's there's another effect of dealing with hydrogen ions and that might be actually reduced pain perception. So with reduced pain perception you might see improved performance in longer duration exercise because your willingness to invest effort will be improved. So we know that people are using sodium bicarbonate now in marathon performance.

Dr Antonio:

So it's interesting that the decrease in pain perception. I wasn't aware of what it is. Is there data combining it with caffeine, Because we know caffeine also has an effect of reducing?

Dr Sparks:

Yeah, I mean there are some co-ingestion studies with bicarbonate, caffeine, but none of them, as far as I'm aware, have specifically looked at pain perception and in fact you know the vast majority of the sort of evidence that there is. I mean, there's some interesting things from, from looking at analgesia and looking at the effects of anaesthesia. So sodium bicarbonate infusions have been used in that field for a while. It brings on anaesthesia more rapidly and improves local pain perception. If you're putting cannulas in, for instance, which again is quite interesting but again has largely been overlooked in the literature quite interesting but again has largely been overlooked in the literature. Um, and well, from a sports science perspective, anyway, you know it's it's been a little overlooked, um, so most of it is kind of joy, us joining the dots, but then also listening to athletes that their their perception is that they feel better, like for like they're doing the sessions, they're not getting that same negative feedback.

Dr Antonio:

Now if you were to use it regularly. Let's say and I hear this about caffeine, I love caffeine If you use caffeine pre-workout all the time, that during a race you know when you're going to enter a race that you might have to up the dose a little bit to get an ergogenic effect. Is there a tolerance built up? If I were to train and take sodium bicarb all or most of the time prior to training, would it be just as effective the day of a race? Or, because it helps you train harder, you would do better anyways in that race. Does that make sense?

Dr Sparks:

Yeah, I think, again, there's not a huge number of training studies. If we're looking at that on its own, um, I think, um, all this kind of common sense and the sort of physiological um processes which sodium bicarbonate could influence make a lot of sense for training adaptation. Um, there's a review from 2020 by rothschild and dave bishop. Uh, that highlights, you know, where bicarbonate has the potential to have an impact on on this type on training adaptations, but no one's really looked at you, you know, is there a blunting effect? My gut feel is that there probably isn't, but then, at the same time, it wouldn't be something that I would advocate you use for every training session. I think that some of that training adaptation might actually come from you having high blood hydrogen ion concentration. So that's true.

Dr Antonio:

Now, if you were, now the other supplement that people use actually quite frequently here, certainly here in South Florida, there's a huge mixed martial arts community and beta alanine is probably their go-to supplement, more so than even creatine, because they don't want to gain weight. But the data on beta alanine seems to at least suggest that the limit is up to I think the number is 240 seconds sort of this narrow window where it helps. Is there any?

Dr Antonio:

evidence that I guess. First compare mechanisms, sodium bicarb versus beta alanine, and would there be any evidence that combining them somehow would be better?

Dr Sparks:

there be any evidence that combining them somehow would be better. Yeah, I mean, they're different in terms of how they're categorized. So sodium bicarbonate is an x, uh, x extracellular uh buffer, whereas beta alanine is an intracellular buffer. So the mechanisms are slightly different, although we do know that bicarbonate is likely to also have an impact on the intracellular pH as well. So I mean again, there's not a massive number of co-ingestion studies, but the sort of meta-analyses that is there only includes 10 studies. It's fairly recent, from last year. Curran and Bowen, I think, was the author for that. Uh, curran and bowen, I think curran, bowen, I think, was the the author for that and they showed in that study interestingly that that, uh, there was a combined effect but not a separate effect across multiple types of exercise, and that has me slightly suspicious because I'm pretty sure that they're. You know, the studies that should be included there should really show an effect of both of them, depending on the protocols, of course.

Dr Antonio:

Wait, there was no effect individually, but there was a combined effect.

Dr Sparks:

Yeah, which is really interesting because you would have thought, given what we know about both of these supplements, that there should be an effect. The problem that you've got methodologically is that the washout period for bicarb is really quite quick, you know. The blood bicarbonate concentrations will decrease, certainly within about 24 to, you know, 36 hours. It's pretty much all gone depending on how you ingest it and what activity you do in the meantime. But with, obviously, with beta alanine it's, there's a loading phase for, you know, four to ten weeks before it becomes really really useful at high enough concentrations where it does become orogenic. So there's a lot. Likewise there's a really slow washout period.

Dr Sparks:

So that makes it very difficult to do really strong study designs. You basically have to have independent match groups to do that well. You can't do a crossover study very well because the length of time between you know the first assessment and you know three different uh conditions within that experiment is far too long and the training effect would make that just far too noisy and the sample size that you would need would be absolutely astronomical to even detect anything. So it's a very difficult study to do well. But I'm a bit suspicious that in those instances there's no single singular effect at all, but there is with combined effects. So it's an interesting finding. You know these things are always interesting, but understanding why that might be is probably now. Meta-analysis is only good as good as the studies that are included in it, and that's.

Dr Antonio:

If that's all that's available, then we probably need more studies now let me ask you this um, with a lot of supplements, it's almost always dosing is provided as an absolute amount just for ease of use. You know, we tell people to take three to five grams of creatine daily. We never really talk about a dose per unit body weight. And even caffeine most people, at least here in the US. They say oh, take 200, 300, whatever 400 milligrams before a race.

Dr Antonio:

Now, with sodium bicarb it's almost always talked about per unit. You know for body weight. You know for body weight. If you were to flip it, is there a absolute low dose that are minimally effective? Absolute dose that might be effective. Just to make it easier to explain to people, because I hate to say it, but in the United States if you say you know grams or milligrams per kilo, they look at you like what is that?

Dr Sparks:

Yeah, I mean it very much depends on the individual.

Dr Sparks:

If you look at, there's a nice study from Jones in 2014, I think it was, and they did a dose response study looking at the individual responses from 0.1 grams to 0.2, 0.3 grams per kilo and for some people just taking a 0.1 gram per kilo dose, um, which for a 75 kilo person is, you know is is not very much at all.

Dr Sparks:

It's like 7.5 grams, um, you know it's uh, it's a really small dose, but that is sufficient enough for some people for it to produce an ergogenic change in blood bicarbonate concentrations, but not for everybody. And that's partly the problem with bicarbonate is the inter-individual variability in our responses to it is quite pronounced, certainly at low levels, and then also the timing of that response is also quite tricky to get right, um, and so that's potentially problematic really, with some of the the research that's there, both from an absolute dose, but then also, you know, that sort of generic time perspective, that can be problematic, um, but yeah, I mean it could be for some people as low as 7.5 grams, but the most widely used one for a 75 kilo person would be about, you know, about 20 grams, I suppose, of traditionally delivered bicarbonates, that's liquid capsules, that kind of thing.

Dr Antonio:

That's quite a wide range.

Dr Sparks:

Yeah, it is, and that's kind of it needs to be like that as a sort of catch-all because of the inter-individual variability it's interesting now, are there any and I get this question quite a bit just long-term safety issues?

Dr Antonio:

if you were just to, let's say, you use sodium bicarb once or twice a week, you know, maybe particularly during really hard training Any safety issues regarding it or totally safe?

Dr Sparks:

Yeah, I mean, it's a question we get quite often and it's largely not to do with the bicarbonate element of the supplement, it's to do with the sodium load. And it's interesting because, you know, in sport and exercise nutrition, there is quite a lot of emphasis, particularly from a sort of commercial perspective, but also from a consumer perspective, on the importance of electrolytes, um, and obviously at the same time we also have this sort of drive from a health perspective to to opt for foods which are low in sodium. Right, that's a bit of a contradiction in terms, but that seems to be the sort of way of things currently. Um, if you're giving, you know, a large dose of sodium bicarbonate, invariably you're giving a large dose of sodium, and for somebody with a cardiovascular condition, that's probably not a great idea. That sodium load is going to be really quite, you know, quite large. And then, but if you're training regularly and you're sweating a lot, particularly if you're doing exercise in the heat, that sodium is we have to remember that sodium is really really tightly regulated in in the blood um, if that sodium is being delivered then and it's not being used or needed, then it's going to be excreted.

Dr Sparks:

So I mean, uh, we would normally work on the basis that you probably shouldn't take it more than twice a week, just out of out of out of. You know, not necessarily based on any particular data, but it makes sense because of the total sodium load. And when you combine that with normal food intake. And we know that athletes take electrolytes, particularly if they're doing really long duration exercise. If you're taking bicarbonate before that bout of exercise, you probably don't need an electrolyte. Um, depending on how long the exercise is. Obviously, if it's a, if it's an ultra, then perhaps lay on an exercise to encourage drinking, maybe. But we know that that's also a side effect of taking bicarb, that it will drive drinking and thirst behavior.

Dr Antonio:

So yeah, I know, um, I mean, depending on where you live in the us or really anywhere here in south florida, people who I mean everyone trains outdoors pretty much all year, and so when I speak to athletes, whether they're triathletes, paddlers, canoeists um, they purposely salt food just because they're, it's basically you're constantly sweating, every hell you sweat when you just walk outside, so so in that case, I don't think sodium bicarb would be an issue. Certainly if you live up north where you know it's cold, like most of the year, it certainly could be an issue. Now, the. I want to talk a little bit about the martin, the bicarb system, um, from your company and how and sort of the genesis of it. Uh, obviously a lot of it stemmed from we could minimize or ameliorate the gi issues. That really was the impetus. But tell us about the, the system you have, and how it differs from just swallowing a bunch of pills or or taking 7.5 grams of straight sodium bicarb yeah, so, um, it's a two component system.

Dr Sparks:

So it uses a carbohydrate hydrogel, which has got 40 grams of carbohydrate in it and a hydrogel is. Essentially it produces like a 3D matrix and it's a delivery system. It was developed in the 1940s and 50s to actually deliver drugs again to try and protect them from the the gi upper gi tract, particularly the stomach acid. So, again, we've already spoken about the idea that I came up with a while back and the research group that I was working with. We, uh, we, we tested this idea of, you know, gastro resistant capsules, and so it morton had stumbled across some of the articles that we'd published from nathan hilton's phd and um and it seemed like a good idea that they have some evidence to suggest that, you know, they can fuel really aggressively with carbohydrates using this system, and it seemed that there was a a nice overlap there in terms of providing a nutrient which, at high dose, which was also able to sort of reduce some of the GI responses. So well, I started speaking to them in 2019 whilst I was still academic and we managed and we managed to get some funding to to uh, to do some work evaluating that. Covid kind of spoiled that because we were hoping to test some of the prototypes but, uh, that didn't happen and so the lockdown in Sweden wasn't quite as severe. So they managed to do the testing in-house for the for the different prototypes, and then they sent us what they thought was the best uh to to go with and it's ultimately what was what was used. And the idea is also.

Dr Sparks:

The other component of the system is mini tablets. So instead of a liquid, it's um, it's mini tablets which are 1.5 by 3 millimeters in size, um, so it'sa. It's actually a patented um formula, um which protects the uh, uh, the bicarbonate from the uh from the stomach acid. But the tablets are small enough to pass through the pyloric sphincter. That's the the way that the system works.

Dr Sparks:

So there's very minimal interactions between stomach acid. So that means that the total works. So there's very minimal interactions between stomach acid. So that means that the total delivery of bicarbonate is really quite high. But because of the nature of the delivery system it's it produces relatively high peaks in blood bicarbonate change. But it also means that recovery between bouts is really good because the area under that blood bicarbonate curve, that response following ingestion, is really quite large. So one of the things that that the literature has not yet done and wrestled with in certainly some of the meta-analyses and reviews, is that not all bicarbonate is the same and that's because of the blood bicarbonate profile that you get after ingestion. So if you take it as a liquid you get a really high peak, but the tail of that curve is quite short and not very long.

Dr Antonio:

Wait, so when does it peak?

Dr Sparks:

What's the time point generally Again? So we did a study looking at the inter-individual variability with liquids and capsules and it can be anything between 15 minutes after ingestion, which is really quite astonishing, and it can be up to 90 minutes in some people. So it varies enormously, Wow. And also depending on what you've eaten prior to that, that will also impact. Having a meal in your stomach will probably prolong the time to peak and it will also make the curve is different and that peak also make.

Dr Antonio:

the curve is different, and that peak lasts how long? Or when does it significantly drop?

Dr Sparks:

Yeah, again, it will depend on the method of delivery. So with enterically coated you get a blunted peak but you get a really prolonged effect. So the area under the curve is probably larger and again, because you're protecting it from stomach acid, the total delivery is bigger, which explains the longer curve. So that means using those for longer duration exercise or repeated bouts of exercise. So I mean the oversimplification of endurance. Exercise is another thing which is probably not helped by carbonate, in that you know most races are not steady state, that you know a particular percentage of max and so there is periods there where you know there'll be very, very intense exercise followed by relative recoveries, and that's why that's potentially useful. But the one thing that's interesting about the the um, the enterically coated and the gastro resistant capsules is the vast majority of participants in those studies they have GI problems from the lower end. Later. So seven, five, six to eight hours, maybe afterwards there is some fluid shifts in the bowel that cause some GI upset.

Dr Antonio:

Oh, but the race is over by then. So right, who cares?

Dr Sparks:

Yeah, but if you're doing multiple day events, that's not helpful. So we know that that sort of technique has been used in the pro peloton in cycling and multi-day stage racing and that's not great. That said some people. They don't have a problem with that, but the vast majority will have some disturbances. So this system is designed to alleviate that and most of the data, as we published a couple of studies. So, uh, goff and sparks is two, two of those studies from last year and then another study by eli shannon. Uh, looking at 40 kilometer time trial performance, that too has minimal gi upset, very minimal minimal.

Dr Antonio:

Now you said there was. Was it 40 grams of maltodextrin in the Martin bicarb system, the part of that gel?

Dr Sparks:

Yeah, it's a carbohydrate mix.

Dr Antonio:

yeah, Is there data separating the effects of carbs versus carbs plus sodium bicarb? That's one question. The other is is there a hypoglycemic effect?

Dr Sparks:

um, if you consume it, let's say, 90 minutes before a race um, there's likely to be a minor rebound effect, but it will depend on what you've eaten prior to that. So normally we would we would recommend sort of three and a half hours prior to exercise. Four to three and a half hours before exercise you would eat a meal, your normal pre-exercise meal, and then 90 to maybe 120 minutes depending on the logistics before exercise, consume the bicarb mixture. Um, so the likelihood is that even if there is some minor glycemic, hypoglycemic rebound, as soon as you do some sort of warmup, that will be reversed anyway. So it makes no difference.

Dr Antonio:

So so that's, that's the key.

Dr Sparks:

That was always you know, in the in the early noughties, the hypoglycemic rebound was always seen as a thing to change your carbohydrate ingestion strategy prior to exercise. But we know that if you, if you, start doing a warm-up, then then that's that can be reversed quite easily all right.

Dr Antonio:

Uh, one last question. When you look at the endurance events, so you know, yeah, run, bike, swim, I sort of group those together, even though they shouldn't be. Um in south florida I'm heavily involved in sort of the water sports the canoe, oc canoe, outrigger canoes, stand-up paddling and the nature of the race.

Dr Antonio:

I guess let's take running. Running is simple. Typically the advice is you want to do a negative split, so the second half typically faster than the first half. I've noticed both racing, stand-up and Outrigger, that it doesn't follow that pattern. It's almost you start with a sprint. Try to take a lead and hold it. There's no. I've never even heard anyone talk about negative splits and stand-up paddling. It's go out as hard as you can and don't let anyone pass you. So I guess the question is would a sodium bicarb, with a sodium bicarb system, be more advantageous for those sports where it's basically we call it fly till you die? Just go out as hard as possible, hold it and hope no one can pass you. What are your thoughts on that?

Dr Sparks:

Yeah, I mean that that intense amount of exercise to begin with is particularly useful. Bicarbs can happen, help with that. There's a couple of studies which have looked at the um, the slow component, so oxygen uptake, and and they show um improvements in the slow component, uh, with uh, with taking bicarb, uh, which is useful, I think, potentially, and then also um, you're going to go off really intensely and and that's going to probably be, you know, relatively super maximal in terms of vo2, uh, percentage of vo2, power output, for instance, and I think then there's going to be a period of relative recovery because you're going to not be able to sustain that initial really intense belt. I mean, it's very similar to, you know, the start of a uh, a tour de france stage where there's a breakaway. You know the flag drops the riders.

Dr Sparks:

Yesterday's stage is a prime example to lose to, to lose um, where the breakaway went with 155k to go and stayed away all day, um, and that's that's exactly it. And you, you know, if you looked at the profile yesterday, you've got a really intense bout of exercise, relative recovery, whilst they, you know, main try and maintain that, that break, but I'm not overdoing it and then a progressively undulating course. So again, intermittent exercise within the injured aerobic exercise. And we know that pro tour riders are using certainly the Morton bicarb system and other bicarbonate deliveries. Lots of the teams are playing about with that.

Dr Antonio:

Where can people purchase the Morton bicarb system? Is it online? Make it easy for them so they can play around with it.

Dr Sparks:

Yes, you can buy it direct from mortoncom and that's based in sweden. Yeah, but there's a us uh site, so it'll, it'll, it'll know. It will know where you are. Okay, good, um.