Rethinking Hydration with Microwearables: A Conversation with WearOptimo’s Mark Kendall 

What if hydration could be tracked as easily—and accurately—as your heart rate? On this episode of the Russo Edge Podcast, host Solomon Wilcots sits down with Professor Mark Kendall, CEO and founder of WearOptimo, to explore how hydration could become the sixth vital sign.

Mark explains the science behind microwearables—tiny sensors designed to measure hydration in real time—and why elite athletes, healthcare providers, and even elder care facilities are rethinking how hydration affects performance, cognition, and long-term health. Whether you’re a sports fan, healthcare innovator, or just looking to improve daily well-being, this episode offers a powerful look into the future of personalized health monitoring.

Solomon Wilcots Welcome to the Russo Edge Podcast. I’m your host, Solomon Wilcots. Today, we’re speaking with Professor Mark Kendall, scientist, entrepreneur, and the founder and CEO of Wear Optimo. From rocket technology to cutting edge medical devices, Mark has spent his career turning science fiction into real world impact. His latest venture, Wear Optima, is changing the way we think about wearables, starting with hydration and how it affects everything. From athletic performance to brain health. Mark, welcome to the Russo Edge Podcast. Great to see you today. How are you doing?

Mark Kendell: Great to see you Solomon, and it’s a pleasure to be here.

From Rocket Science to Healthcare Innovation

Solomon Wilcots: Well, it’s a great pleasure to have you. Let’s get started with your personal story. Now you started in aerospace engineering and now you’re pioneering new ways to monitor the human body. Walk us through that journey, Mark, and how did it lead you to wear Optimo?

Mark Kendell: First of all, I love rockets, always have, thought I’d still be working on rockets today. I did my PhD in rockets a long time ago. I was funded by NASA, it was on hypervelocity aerodynamics, it was working on the world’s fastest wind tunnel for Mars reentry vehicles. I thought I was going to go to California to continue to work on rockets. I had a job lined up to go Caltech JPL, which is one of the meccas. It was fantastic.

Then a two-minute conversation just changed everything. I met a guy at a conference, and he came up to me and said “I really enjoyed your presentation I have this idea to give rockets to vaccines into the skin. Would you like to come and work with me?” I thought, “Wow that sounds really interesting,” and I had two questions the first was “Where are you doing this work?” and he said at Oxford University and my second question is “Would I get a chance to row?” and he said if you’re good enough. So instead of going to California to work on rockets, I instead went to Oxford.

What really resonated with me was instead of a lot of rockets being used as filling machines, this turned it on its head, we’re actually using that force for health care. That’s how I got started on that journey and I haven’t looked back. It’s been 27 years, and I’ve been working in global technologies for healthcare since.

Redefining Wearables With Deeper Biological Insight

Solomon Wilcots: Well, your work today focuses on something called micro wearables. What exactly is micro wearable and how is it different from the smartwatches or fitness bands that we already know about?

Mark Kendell: That’s right. I have one example of what our product is set to look like. This is it here. Of course, we all know what smartwatches are. I’m wearing one today. Smartwatches are very useful, but they’re very, very limited. The skin is just a great barrier, and it does its job. If it didn’t, we’d be dead, right? It keeps the bad stuff out, and the good stuff in. Things like Apple watches, they gain access to a few things, but a good way of thinking about the skin is think of it as a wall and you’re trying to get access to another room, and an Apple watch is like putting your ear against the wall and miss an end. You can’t really hear much, it’s muffled, right?

Now another device is out there, which is the continuous glucose monitoring device. I have an example of one of the commercial products here and you all can see that. What I’m holding in my hand is effectively the most successful medical device in human history. It’s not by us, it’s by others. If you have diabetes, this has changed your life entirely. It is fantastic. Millions of people use it, and this is much better than blood cricks, etc. But that’s glucose and it’s a massive needle.

I knew all of this and I thought, well hang on, I’m a founder of this field called Microneedles of been working in that space for 20 years and I thought well hang on there’s something here, what if we just have microelectrodes gain access to signals, like listening through that wall without putting a big hole in it like a CGM. It feels like a sticker but actually it’s reaching in and gains access to all these signals and that’s what we’ve done. I’m really pleased with what we’ve achieved so far and excited about the impact that our tech is set to make.

The Hidden Health Risks of Chronic Mild Dehydration

Solomon Wilcots: Well, your ability to detect anomalies, I think would have to be very intricate. Let’s talk about hydration. Most people think about dehydration, and it just means maybe drink more water, but it turns out it’s much more complex than that. What’s the real science behind hydration and why is it such a critical metric in sports?

Mark Kendell: Oh, you’re right, Solomon. It’s a massive, massive area. Rightly, people talk about dehydration, but you can over hydrate as well. Particularly in athletic settings, there’s been a multitude of deaths from people drinking too much water and dying there. The overarching term we use is miss hydration. Okay, so you can be under hydrated or over hydrated. The science of it is really, really compelling. When we think of, when most people think about dehydration or hydration, they just reach for a cup of water and think everything is sorted. It’s actually a far, far, far bigger problem than that.

Thirst doesn’t do the job. If you rely on your thirst, it’s too late. Thirst only kicks in when you’re massively dehydrated and mildly dehydrated is the wrong term as well because malt is bad and let me explain why. There’s an explosion of work, Solomon, in the last few years. It’s not the work of ours; it’s the scientific community beyond WearOptimo. What they have shown is really confronting. Half of Americans are chronically and mildly dehydrated. You might be thinking, well, that’s no big deal. I’m surviving. I’m doing okay. It’s not bad at all.

It turns out it’s putting the body in a type of stress. When you’re under that stress, your body’s got to adapt. But when you stress, you’re not bringing your A game. You’re putting on switches. You’re in working in a less-than-optimal way. What’s being found, not our work, others, is that it actually has a massive, massive impact that it’s reducing your life expectancy by four years. That’s on par with something like a glucose, it has its own disease, it would be just like diabetes, right? Everything in the body that’s interconnected, the impact goes in many different ways.

It makes everything else worse as well. Six of the top 10 diseases as they exist are a lot worse if your background is being dehydrated. Let’s just choose one as an example. Let’s talk about dementia. Let’s play a little bit of the game. Solomon, when you’re dehydrated for a significant period of time, it increases your incidence of dementia. Guess how much it increases your dementia incidence by what percentage?

Solomon Wilcots: 10%? 20%?

Mark Kendell: 48%! That’s just that example and there’s many, many others, right? People knew hydration was management was a big problem. They didn’t know this big, it’s not even just all of that, which is massive in its own right, it’s how we roll in our day to day lives. If we’re only 3% dehydrated it effects our brains, the equivalent of being drunk, over the blood alcohol limit. Then this is where we get into one of our favorite topics. I’m looking behind you; I can see a myriad of great sporting paraphernalia.

I love sports, you love it more because you’ve been a lead athlete, credit to you. Sports, it plays up big time in the sporting domain. Because if you’re mildly dehydrated, it reduces your strength by about 7%. It reduces your endurance and that cognitive function, your ability to concentrate, that’s important too. You get sloppy in the sporting field scenario, so injuries happen a lot more as well. 7% is a big number in elite sports. If you’re in the 100m race, if you feel 7% off, you’re nowhere. That’s the thinnest of edges. Well, there’s still the fathead to be gained by just improving your hydration management, let alone the thin edge. I’m quite excited about that context.

Real-Time Hydration Monitoring for Elite Performance

Solomon Wilcots: What can people in elite sports like rugby and formula one racing or even football, what can the teams or our coaches begin to do real time to monitor hydration and then bring about a better solution of catching it before it becomes problematic?

Mark Kendell: Let’s talk about Formula One. One of the reasons why is one of our investors is Mark Webber, a former Formula One champion. He talks about he did a race at Monaco some time ago. His car hit the wall at 200 miles an hour, okay, and then they did the post analysis of what took place and turned out he was dehydrated and affected his cognitive function. Now one of our advisors is Luke Bennett, the former chief medical doctor of Formula One, so we’re working quite closely with him on this. There is a bottle of water that sits behind you in a tube, and the drivers don’t want to think about that when they’re driving, they’ve got a lot going on. Our sensors will serve as a prompt, right? Another bit of information, take on board this, and as a way to take that off their mind so that they can stay at peak level.

Now that’s just one example. Now talk about tennis. We know players like Pat Rafter, won in the US Open, Australian great tennis player, former, I think he was world number one or thereabouts. In conversations with Pat and people like Pat we call a sweater, he sweats a lot. It got to such a point that it’s playing on his mind. Before a big match, instead of getting in the zone and thinking about the game. He’s there worried about what am I to do? Should I drink more or should I not? How do I handle all of this? That clutter is very important in the world of an elite athlete as well. That’s just a couple of examples.

If we talk about impact sports, you’re a man of impact sports. Football, that plays out in many, many domains. When you hear that term fatigue, what is it? A big part of that fatigue is your hydration has gone down and as a result of that, your body is in a type of stress. Your concentration is off. If you’re tackling, you’ll get sloppy, you get injured more. It’s actually highly correlated with a massive increase in your injuries and then there’s one extra bit Solomon that most people are not aware of but it’s a big issue. Concussion.

Solomon Wilcots: What are the links? Are there any links between hydration and concussions? Have you been able to establish any of those?

Mark Kendell: The work of others, rather than ours, is this. Firstly, everything I’ve just talked about, of course, applies to concussion. If you’re fatigued, you’re sloppier on the field, you miss a tackle, a hit goes wrong, impact, concussion, so that’s significant. But most people kind of get that. The real sort of aha moment is this additional piece. The brain is mostly water, and it turns out that one of the biggest determinants of when an impact event happens for your level of concussion is how hydrated you are at the time.

Let’s just talk about it for a second. Say you’re a bit dehydrated and you have a hit, or when that takes place, your brain is already in a form of distress. That’s the starting point. It sets you off on a much worse path of distress as opposed to being in its best form of itself as a starting point, and there’s a lot more science associated with that, which I’m happy to get into in deep physiology, but that is the take home message.

Bringing Hydration Into Routine Health Monitoring

Solomon Wilcots: Really phenomenal and very impressive knowledge that I think a lot of athletes are going to now begin to explore just how hydration is one of those critical signs right for determining our health. When you talk about establishing our own vital signs, how important is hydration on the list of our heart rate, our pulse, the things that our doctors and our trainers are constantly checking. Why isn’t hydration on that list and should it be?

Mark Kendell: There’s the medical community, doctors, nurses, practitioners, they have their five vital signs as the dashboard, right? You keep an eye on things and when things are in the wrong direction, you take a deeper look at the problem. There is the five, they include heart rate, your temperature, et cetera. They’ve actually been around a very long time. Although there’s one newcomer, which is your oxygen saturation, that’s come on board in the last 20, 30 years or so, but that’s pretty much it. There’s this massive push from the medical community for hydration to be the sixth vital sign.

When you’re out with your hydration, there is a lot of reasons why you need to take a deeper, deeper, look. It’s one of the biggest indicators of your general health. Probably something else to add, Solomon, we didn’t really get into it. Elite athletes are there and that’s really important and it matters in every domain but as we get older probably like a lot of things in life it just gets a lot worse. About half the things that go wrong for someone in eldercare is directly attributed to poorly managed hydration

Where Micro Wearables Fit Into the Future of Health Tracking

Solomon Wilcots: I think it’s just incredible. Let’s zoom in maybe a little bit and where do you see micro wearables fitting into the future of monitoring the health? You just talked about some of the vital signs, and it should be listed as that sixth vital sign. I think that’s very important. But how does your work help to compliment what’s already there, like the Apple Watch that we talked about, the Fitbit, all of these different devices. How does it help to complement or maybe go along with some of those devices?

Mark Kendell: I think they just had the 10th anniversary of when the first Apple watch came out. There are a few things they can do. Having a genuine hydration measurement and having a pluggable and playable. You can imagine what we’re producing with this ultimately could be embedded within. The way it plays out, there’s a myriad of possibilities and opportunities there. Solomon, we’re beginning with elite sports first. The reason why is elite athletes are like the Formula One engines of humanity.

Solomon Wilcots: I would agree, I would agree.

Mark Kendell: They put themselves through so much more than the average Joe would never do, right? To run a textbook marathon these days, you put your body through about 8% dehydration to run. These guys will benefit the most and that’s why we’re beginning with them. They’re putting themselves through the most, so we’re getting this amazing data. Life at the extremes with the lead athlete, which helps build our algorithm and make it even stronger. Then we deploy into all those other models that I’ve touched upon before.

Reducing Diagnostic Uncertainty in High-Impact Sports

Solomon Wilcots: I have one last question for you, being an old football player myself, there’s been a lot of discussions about concussions, and I know you mentioned this earlier. How much do you think the monitoring of hydration could help delineate between those vital signs that people are thinking when someone is distressed, maybe having a concussion, but in reality, they’re just suffering from dehydration. Since the two sort of mirror one another, how much can this help to alleviate maybe some of the stress in that area and help provide a more healthy and more consistent diagnosis when it does come to concussion?

Mark Kendell: All the science of point and call that have a massive impact. What’s really interesting is that the level of that hasn’t yet been determined because the sensor hasn’t been deployed, haven’t been a way of doing that, but if I just illustrate it with a sort of different example to elite sports like elder care. There are situations where people think they have delirium or even dementia, right? They have all of the signs of deliriums and dementia. It’s traumatic for them. It’s traumatic to the families. It’s massively traumatic. Imagine your family member has sudden onset dementia and then they get rehydrated and then they’re fine.

That’s just one example that illustrates that point, but you map it back to elite sports. I have a lot of empathy for elite sports. I’ve never been one, but I have an empathy for it because it’s what they love doing, their time doing it is limited, it’s extremely competitive by its nature and there’s a lot riding on it because of this fusion of the thing you love to do but it’s also your job as well. You do not want to get injured, your team doesn’t want or you do not want your performance to drop. I’m not saying what we’re doing is the silver bullet. It’s not, but there’s a massive gap there that’s left on the table. If you maintain your hydration within your sweet side, you’ll be taking away quite a few of those other contributing factors that are problematic right now.

Solomon Wilcots: Really good stuff. I can’t thank you enough to Dr. Professor Mark Kendall for joining us today from the field to the racetrack and from deep minds to military front lines. Your work is really helping to reshape the way that we understand the body in motion. I’m Solomon Wilcots. We want to thank everyone for joining us.