Aidan:
Hello and welcome to the Ideal Nutrition Podcast. My name is Aidan Muir and I’m here with my co -host, Leah Higl and this is episode 148, where we’re going to be talking about whether probiotics can be beneficial for athletic performance. On the one hand, I think this is a little bit of a weird kind of angle to look at it in terms of like, I don’t think anyone sitting here thinking I’m gonna take probiotics and that’s gonna add like 10 kilos to my bench press. Like I don’t think it’s anything magical like that. But there are a few angles I look at this from in terms of either directly potentially helping or indirectly helping.

One of the things is there’s a bunch of research that probably like five years ago, I was starting to see where they’re looking at the microbiome of endurance athletes in particular and pointing out a lot of big differences in the gut microbiome of endurance athletes at an elite level and just the average person or even like recreational endurance athletes. That’s enough to get you thinking but obviously that’s a chicken or the egg scenario about being like, is their training and the way they live is that why they’re microbiome is like that?

Or are there other things that happen to line up like that? So that’s one angle but the other indirect stuff is what if probiotics meant you got sick less frequently? So you missed less days of training, had fewer days of competition impacted by illness that could obviously carry over. What if probiotics had any impact whatsoever on body composition that would obviously indirectly affect things. And there’s a few other angles that we can look at like that.

The final thing is that there was a systematic review done in 2023 reviewing all the randomised control trials looking at probiotics and performance, and they found 13 relevant studies. And 11 of the 13 found positive benefits. Not all of them were statistically significant, but when you start looking at it like that, you’re like, okay, it’s starting to look a little bit more promising. There are still so many gaps in the research.

One of the biggest examples is that a lot of these studies are only using individual strains, then the fact that, and like most products contain multiple strains, and then the fact that there are so many different strains that could be looked at, so many different combinations, so many different dosages, there’s so much more to know, but there’s enough to at least be like talking about the topic to start off with.

Leah:

Digging a little bit deeper into the illness side of things from a probiotic standpoint, the link at first glance doesn’t seem super, super clear but there are a number of mechanisms as to how probiotics could reduce things like upper respiratory tract infections specifically. To try to keep it more simple just for the podcast format, I’m going to go through four reasons as to why this could be. Number one is that they can play a role in the immune system, so probiotics specifically, and stimulate the production and activation of certain antibodies.

Number two, they can also strengthen the barrier of the mucosal lining in the digestive tract, making things difficult for pathogens to get through that intestinal lining. They can also inhibit the growth of harmful bacteria. And then the last one, they could reduce inflammation. And that inflammation could play a role in the symptoms of an upper respiratory tract infection. An interesting piece of research is a 2022 systematic review that found 16 relevant studies and the majority found improvements in either the reduction of the risk of getting sick.

So the number of times people were getting upper respiratory tract infections or reduced duration or severity of the illness. So whilst there wasn’t huge improvements, they are still definitely relevant and the research is kind of promising in this area. When you think like if you’re sick, less days, that’s probably less training days that you miss as an athlete, which overall could lead to better adaptations because you’re training more often and at a better, just better frequency and a better quality and not missing so many due to sick days.

Aidan:

There was some interesting survey data from like, I don’t know if it’s like the IOC, it was definitely something Olympics related, where they were looking at what percentage of training days were impacted by illness, what percentage of competition days are impacted and just how many things are just mis-gestured illness in general. And the numbers ended up being quite high, like it was a decent portion of the year. Like I don’t want to misquote it. Like I think it was like at least a quarter of the year appeared to be like impacted in some way.

Cause like, you know, when you get sick and then there’s still weeks after that where you’re like not quite perfect. And once you’ve looked at those kinds of stats, you’re like, can see this starts adding up over time. It’s worth, even if it was like a 10 to 15% reduction in the likelihood of getting sick and or duration of those illnesses and the impact of those as well. You could see why it starts getting a little bit worthwhile.

Leah:

Particularly relevant to those athletes that are more at the elite level and are pushing their training load and like in overreaching phases where illness maybe like the immune system maybe like taking a bit of a hit and this could be more of an issue.

Aidan:

Yeah and like travel as well which we’ll probably talk about later like in higher risk areas it makes heaps of sense. So the next thing we’re looking at is probably something that comes to mind more when we are talking about probiotics which is the impact on gut symptoms and obviously it’s pretty well established that probiotics can help with IBS type symptoms. And that could translate to improved performance in certain athletes.

Like for example, if we’re looking at ultra endurance sports, it’s not really uncommon for people to run into issues from a gut symptom perspective that can then impact their performance. So theoretically, if we had an improvement there, that could carry over to improved performance. That’s another indirect type of benefit. There’s not heaps of research on that, but there is like a handful of like randomised control trials that is looking at IBS type symptoms in athletes and it seems like mildly positive.

I wouldn’t read too much into that. Obviously more studies are needed, but like it leans in favour of like slight evidence of finding improvements in GI symptoms in athletes during training and competition. It’s more of a watch this space area for me. Like if I was working with somebody who was in that ultra endurance type space and they were running into this issue, I would add a probiotic because from my perspective, I’m like, there’s no downside to doing this. It might help a little bit. There’s a bunch of other things that I would try as well, which is probably beyond the scope of this podcast, but that is one thing I’d add. it’s like, either it doesn’t work or it does work, but it’s worth trying probably.

Leah:

A less clear area that we could also take a look at in terms of probiotics and athletes is recovery and inflammation. A 2021 randomised control trial, so just the one, found less muscle soreness versus placebo and lower CRP. CRP being a protein which is found in higher amounts in the body when inflammation is high and improved sleep when these probiotics were taken. So the group that had the probiotics, there was this result of lesser muscle soreness and inflammation bound. This was in a group of elite rugby players over 17 weeks of competition and the probiotic was ultra-biotic 60 and they also used Saccharomyces boulardii.

Did I say that correctly? Whenever it comes to probiotic names, I’m like, no. But that’s the one another specific strain that they used. Other studies have found small reductions in things like oxidative stress and reduced inflammation markers. But it’s not necessarily at a point where we would be taking this super seriously and recommending it to athletes for this purpose alone.

Although in covering this topic, it’s an interesting area of research and something to note.

Aidan:

Yeah, 100%. I think it’s a stretch versus like, well, we are covering probiotics. Like, let’s see if there is anything there. But it wouldn’t be like, I’ve written articles on how to like reduce doms and stuff like that. It’s like, doesn’t even make the cut because there’s so many things. Now let’s look at more direct stuff. So we’re looking at I’m going to try and cover strength and endurance and I’m probably going to do it pretty briefly. Some research on endurance athletes has found improvements in performance as measured by things like time trials and time to exhaustion tests. There has been no difference identified in body composition and VO2 max though.

Research looking at strength has found inconsistent improvements. I definitely am not sold on that type of stuff. just like the mechanisms that make sense. If there’s not an improvement in body composition, are we actually expecting improvements in strength? Like I doubt it. Most of the research has been performed on endurance athletes and not strength athletes, but there’s still not heaps. This is another area where I think it’s too early to be excited, but it’s still worth watching. And using myself as an example of how I would interpret this, like I am gonna try and run a marathon this year and I wanna get a decent time.

I’m personally not going to take a probiotic just for this. And I’m somebody who’s like open to being early on stuff if I’m wrong or anything like that. But I’m like, I don’t know if you open the window to being like, I’m going to take this because there’s like a little bit of evidence like suddenly you’re taking like 20 different supplements. And I’m not at the point that I would be doing it for this purpose.

Leah:

Yeah. So talking a little bit now about how we can practically apply everything we just went through. So what circumstances may you want to consider a probiotic as an athlete? So obviously there is not as many clear-cut links as we’d like for a general recommendation as like all athletes should be taking a probiotic. We’re not quite there yet, but the research does show some promise in some of these areas. I’d be a lot more likely to use probiotics for very specific cases. As you said, for example, if someone is travelling or they’re in an overreaching phase where maybe they’re struggling with their immune system, maybe they’re consistently getting sick. Then something like this makes a lot of sense.

‘I work with one pro wrestler who basically for their job, they travel the world and do pro wrestling and constantly, constantly travelling, constantly training, constantly doing shows. And they were always getting sick. That is like the one time I’ve actually said, Hey, let’s take this probiotic and put it into your supplement stack just in hopes that it might reduce the risk of them getting more upper respiratory tract infections was because that’s the thing they were getting most often and it was putting them out. It was like costing them money because they couldn’t do shows. It was putting them out of training.

So in very specific circumstances, it is something that I would recommend. We could also look at it from the point of view that most people should be having a probiotic rich diet or at least be including probiotics from a food perspective that and prebiotics if we want to take it and brought it out that far. But it doesn’t necessarily mean that a probiotic in supplement form would be of extra benefit. I think it really is just in these like specific cases where it is like super relevant. If you are interested, we do have a blog post going through how to pick the right probiotic for you because it should be very strain specific.

There are so many kinds of probiotics that all kind of do different things and have promising research in different areas. So that’s going to be listed in the show notes. It’s not specific to athletes, but it’s still relevant and you can still have a little look through and see what may be suitable for you. An overly simplified approach to looking at probiotics that you could use and I think makes a lot of sense is just finding a reputable brand that is a multi-strain formula.

So having kind of just casting a wide net and you’re like, well, it’s a good brand. There’s a whole heap of strains of probiotics in here. That could be a decent way to go. The research on different strains and what they can do is still kind of unclear. So having this kind of multi-strain approach, I think does make sense to a certain degree. But if there are certain strains that are linked to specific benefits that you’re looking for, then that’s something you should also keep an eye out.

Aidan:

Yeah, I agree with all of that. I’ll even double down on that. Earlier you said about like travelling and stuff like that in that I’m pretty sure the AIS guidelines for the Australian Institute of Sport, their guidelines specify that like for pretty much everybody who’s traveling for international competition to, they recommend probiotics for that. Because like it could be like what if it reduced your likelihood of getting sick? What if you might have got travellers diarrhoea or something like that? It’s like what if it reduces the odds of that? Like what if like it makes you more comfortable having different foods because of all of these things. Like there’s so many ways that could help so like.

I’d really push that like anytime I’m working with somebody who is traveling internationally for competition, because it’s like, say they’re a power lifter and they’ve been like going through like a peaking phase, maybe the risk of getting sick is even higher during that anyway, potentially from the overtraining perspective. I’ll have them start before that have that take it all the way through to traveling and then leading up to competition as well. yeah, that’s another thing that I’d look at.

Leah:

Something that is available is the Yomogi brand of probiotics that is specific to travelers diarrhea. And sometimes I’ll recommend that someone take that a of weeks leading into travel and during travel. And that could be something, if you’re going to somewhere where the food may cause an issue for you or the water, then yeah, cool thing to add in.

Aidan:

Perfect. That’s our summary. So the one thing I do want to do a sneaky plug for is we have a mailing list that we have upped our game on recently. like the way to find it if you are interested in going to just our website, ideal nutrition.com .au and there’s a sign up link there. Basically at this stage, all we’re doing is once a month, we’re trying to put out a short, sharp, informative email on some nutrition topic that could be beneficial for you. Over time, we’ll probably expand it from there, but right now we’re just trying to do one good piece of content every month. So if you’re interested, go to our website and sign up.