 Come halfway across the world to speak at this conference and I wake up this morning and I have no voice, which is not ideal, considering I was meant to be speaking in a few hours, so if you have to bear with me, I will be taking a few breaks to have a few drinks. So I feel very fortunate and privileged to be here and I'm really excited actually to share some of the work that we've been doing, looking at float and recovery in elite athletes. I just want to acknowledge the organisers of this conference. Thank you very much, not only for putting on a fantastic conference, but also for bringing me all the way over here from little old New Zealand. Is there anyone else here actually from New Zealand? One person at the back, one or two at the back, okay. It's a little bit annoying because I won't be able to make up stuff about New Zealand with some kewies in the crowd. So just to give you a little bit of background about New Zealand for those that don't know, so if we actually appeared on a world map, we would appear about here. Unfortunately, like this one from Ikea, we don't always feature on the world map. So we have to draw it on ourselves. So we're a small country, we're a small country of less than five million, which I understand is even smaller than the state of Colorado. And some of the things that New Zealand is known for are our beautiful scenery, our beautiful landscapes, beautiful walking trails, those sorts of things. And I thought I'd just share a quick little story from what happened the other day. So when I got in to Denver, I decided to go to the gym here at the hotel and I wanted to go and run for about 30 or 40 minutes on the treadmill to try to get rid of some of that jet lag. So I went and stood on the treadmill and I started running and this screen sort of come up on the treadmill, as you can see here with a random video. So I was running and watching this video and it moves along so you feel like you're running on this beautiful trail. And then about a minute into this run, I thought, actually this place looks quite familiar. And so I keep running and then I thought, yeah, this is a running track in New Zealand that I do regularly. And just to illustrate how small New Zealand is, as I was running on this track, I actually saw one of my friends from high school. So some of the other things that New Zealand is known for is our adventure tourism, things like bungee jumping. And for some of you, you may recognise Lord of the Rings was actually filmed in New Zealand as well. But probably the most common thing that people know about New Zealand is our national rugby team, the All Blacks. Now, the All Blacks are one of the most, there's some Australians in this audience. The All Blacks are one of the most successful professional sporting teams in history, in any sport. They have a winning percentage of around 80% and in New Zealand, in our biggest city, which is Auckland, at the stadium there where they play often, they haven't lost a game in over 25 years. Thank you. Now, I know some of you will be sitting there thinking, yeah, that's all right to be good at a sport that no one else in the world plays. So I thought I'd show you that we're okay at some other sports as well. So what we have here on this slide is two figures showing the Olympic medal tally for 2012 London and 2016 in Rio. Now, this tally is scaled for per head of population. And so pretty regularly, we come in the top three on the scaled medal tally. So we do go quite well at sport. Now, you may be thinking, who is this proud kiwi bragging about sport? What's the purpose of this? The reason I tell you this is that we don't have the luxury of having hundreds and thousands of athletes. So the athletes that we do have, we have to look after them. And so what that means is that we have to pay a lot of attention to things like sport science, to load monitoring, and just to make sure that our athletes don't over train, get injured, or get ill. And I think that's something that we do fairly well in New Zealand, same in Australia. We do a good job of looking after our athletes. And one of my main areas is athlete recovery. So this is an area that I've been researching and publishing papers in for probably the last 10 or 12 years. And I like to show this pyramid when I talk about athlete recovery. So in the top part of the pyramid, these are what I call the one or two percenters. Okay, so at the very elite level, the one or two percenters are still very, very important. They may be the difference between winning a medal at the Olympic Games or not. But the bottom half of this pyramid, these three down here, these are what I call the fundamentals of recovery or the big rocks, if you like. So we have sleep, which is massively underrated, not only in athletes, but also in general population. And we heard some of that, you say, from Josh's talk. And that's the area that I do most of my research in at the moment, sleep. I'm trying to enhance sleep for athletes. Nutrition, also vitally important, making sure that recovery nutrition is optimal for our athletes. And then just general periodisation. So just making sure that the training load is adequate and there's enough rest and recovery. So when it comes to the one percenters, you'll note that I'll put float up there. So I think if we're looking at acute recovery, so if we're looking at doing a float between exercise sessions, for example, on the same day, I think it probably is maybe a one or two percenter in terms of performance enhancement. But one of the things that I really like about float is it has the potential to impact and influence one of the fundamentals of recovery, which is sleep. And so I'm going to show you a little bit of data that we've been collecting around that recently. And just through the slide in last minute, and one of the things that we've done is develop an athlete-specific sleep behaviour questionnaire. So we published this in Sleep Science in 2018. And the thing we did was we sampled hundreds of athletes all around the world, elite athletes, some of the world's best athletes to design this questionnaire and find out what are the unique challenges that athletes actually face with their sleep compared to sort of a healthy non-athlete population. And we came up with 18 items, and you can see them up there. And what the athletes do now, this has become very well used all around the world and you're welcome to use it yourself if you're working with athletes. So what they do is they fill out these 18 items on this scale. And anything where the athlete indicates, perhaps sometimes frequently or always, we will usually look at what that item is and then we will try to stage an intervention or try to work on that and try to help them out with whatever they're struggling with. And I was just thinking about this yesterday as I was listening to a couple of the talks and I thought, actually Float could have its place in a number of these maladaptive sort of sleep behaviours that athletes are having. So things like item seven, I go to bed with sore muscles. We know that Float may reduce muscle soreness and I'll talk about some of our data soon. So maybe that could impact there. Also item eight and nine, more psychology, thinking about their sporting performance when they're lying in bed or worrying about other things when they're lying in bed. Item 10, sorry, not 10, 14. So we have, I wake myself and all my bed partner with muscle twitching. Perhaps we can use Float to try to reduce that. And then 18, we have travel gets in the way of building a consistent sleep wake routine. So elite athletes are having to travel a lot. Perhaps we could be using Float more to counter that jet lag and the travel sort of fatigue. So today I'm going to share two studies that we've been working on. And this first one is a bit old and ousted. This was published in 2016 and some of you would have seen it. And what we did in this study, this was the data was collected leading up to the 2012 Olympics in London and this is when I was working in Australia at the Australian Institute of Sport. And we just wanted to have a really simple look at athletes that were using Float tanks. All the athletes in this study were habitual users so they'd all been floating for quite a while. We had 60 elite athletes, which is a pretty good number. So they're all international standard. A lot of them went on to compete at the Olympic Games, the ones that were in this study. And what we did was we just wanted to have a look at mood state pre and post a one-off Float. So we used a multi-dimensional mood state questionnaire which had 16 items on it and then we also had a perceived muscle soreness questionnaire. So the participants were a pretty even split between male and female, 28 male and 32 female. So in terms of the results, so this is just showing the 16 different items on the mood state questionnaire that we used and this is the delta or the pre to post change, pre to post change, Float change. What we have here is the asterix that represents a statistically significant difference pre to post and because I don't think that statistical significance necessarily always tells the full story, I also like to show effect sizes using Cohen's D effect sizes. So I think effect sizes are really helpful because they just give us more of an idea about the actual magnitude of the change that we're seeing. So we found significant pre to post changes in 15 out of the 16 mood state variables pre to post vote in these 60 elite athletes. The only thing that didn't change was the feeling of being alert. And if we have a look at some of the effect sizes, so if we just look at the large ones that are bolded, so they were feeling less worn out, they were feeling less tired, they were feeling more relaxed, they were feeling more at ease, less tense and then more fresh, yeah, fresh. In terms of our muscle soreness, we also had a significant decrease, which was associated with a large effect size. One of the interesting things from this study was that we decided to follow up with the athletes after they filled out their questionnaire and that sort of thing and asked them, did they fall asleep or did they nap during their float? And so what we did was once we found out how many of them napped and there was 27 that napped or reported napping, and it's a bit of a crude measure. It's sometimes hard to know if you actually do fall asleep in the tank. 27 napped, 33 didn't. And then we did some further analysis. So this figure here is showing the effect sizes for the same 16 different mood state variables. The double hashtags refer to a moderate effect size. And we actually found some pretty interesting findings that perhaps when these athletes were napping during their float, they were getting even more benefit in terms of these mood state variables. So things like feeling even less worn out, more relaxed, more at ease, less tense, more fresh, and less exhausted when they're napping with the ones that napped versus the ones that didn't napped. Now we've seen a real exponential rise, I think, in athletes using float tanks. And there's lots of reports about high profile athletes, not just over here, but also in our country in New Zealand, using tanks and reporting the benefits. And I think with this increase in athletes using float tanks and that sort of thing, the mainstream media is also really picked up on it and run a lot of stories about these athletes using them. And one thing that I've noticed in reading some of these media stories is that often they will cite that paper that we published in 2016. And that sometimes confused me because I thought it was by no means a comprehensive study. It was really just a pilot, quick and easy study to look at float. And I thought, why do they always cite this paper? And it turns out that there's hardly any research looking at published research, looking at float in athletes, especially elite athletes. So it really did make me feel like we have to do more in this space. We really need to do more. So that brings us to our newest study. So this one's hot off the press. We only finished this one earlier this year. And it's in review at a journal and it's looking pretty positive. So I'm hoping it's going to be published in the next few weeks so you'll be able to have a look at it when it comes out. So this time we decided to have a bit more of a comprehensive look into floating with athletes. And we had 20 well-trained team sport athletes. And what we wanted to do was actually look at fatiguing them using an exercise task at night and then following that, they would either float or do a control trial. And then they would go home and go to bed. They would sleep. And then the next day, they would come back and do a whole heap of measures. So just to talk you through the design of this study, and this is quite a busy slide, but I will walk you through it. So it was a randomized crossover trial where they did a float and a control. The control was sitting in a recline chair in a dimlet room, no phones or anything like that. So it was pretty relaxing as well. So what we did was at 6.30 at night, the athletes came in and did a whole heap of pre-exercise testing measures. We'll talk through those in a second. At 7 o'clock, we fatigued them. So we used an exercise task to fatigue the athletes. Then we had another testing session of the same measures. And this was just to make sure that we were actually causing fatigue in these athletes. So that we were seeing a drop in some of these measures. At 7.55, they had their one hour recovery period. And then at 8.55, we did some more measures, and then they went home to bed. So they wore, when they went home, they wore a wrist actigraph, a fatigue science ready band is what we use, which is being validated against a polysemlography for actually measuring different aspects of sleep. Next morning, they came back and did all the measures, and then we tracked some of the measures 24 hours post as well. So just to talk through quickly the measures that we took. We had salivary cortisol. We wanted to get a measure of stress, so we took that at multiple different time points. We would have liked to have taken blood, but wasn't practical in our setting. We had some perceived measures of muscle soreness and physical fatigue using validated scales. Has anyone seen one of these devices before? No, so this is called a pressure-to-pane algometer. So what this does is it actually tells us about the pressure-to-pane threshold. So you push this device down on a muscle group, and then the athlete or the patient signals when the sensation changes from pressure to pain. So we use this on three different lower body muscle groups. Our strength measure was an isometric mid-thigh pool. We had a speed measure, which was a 15-metre sprint, where we took 5, 10, and 15-metre time splits, and then we also had a repeated sprint test. So they did three of these sprints on a 20-second rotation. We had a power measure, which was a counter-movement jump. So this is a counter-movement jump where we attached a linear position transducer. This is the tether that's attached to the bar here, and the athletes would do three jumps and we would take the best measure for analysis. Now, in terms of the actual exercise or fatigue task, we use something called the basketball exercise simulation test, and this was created by some colleagues in Australia, and it's designed to match the actual physical demands of a basketball game. So that's what we use as our exercise task or fatigue measure. Okay, so what are we fine? Just have a look at the cortisol first. Now, this figure here is just showing just the float condition, so not the control condition. So the green bars here are the overall mean for the whole group, and then the individual lines or the individual athletes. So, as you can see here, on average cortisol levels went up quite a bit pre-to-post exercise. This was a significant increase in cortisol, and then we saw a significant decrease from post-exercise to post-float. So, while this change here was significant when just looking at the float condition, there was no significant difference between the control and the float conditions, which was quite interesting, and I think perhaps one of the reasons for that was that the control trial was also really relaxing, so they were in the dimlet room, they were reclined on chair, they weren't allowed to use their phones or watch any TV or anything like that, so it was also pretty relaxing. But you could probably suggest, so this is the pre-to-post change in cortisol as a percentage, and you could suggest that maybe there was a trend for it being greater in the float trial. Okay, so let's have a look at some of our other measures. Sleep, my favourite one. So, as I said, we measured this using actigraphy, and I'll just talk you through what all these measures are. So, the first one is actually just a perceived sleep quality out of 10. So, we see 7.7 after float, 5.9 after control. These are the p-values, so showing the statistical significance. This was the only statistically significant difference between trials for the sleep variables, but what I've also got here is, again, the effect sizes, because I think that tells us sometimes it'd be this story, so that was associated with a large effect size for perceived sleep quality in favour of the float condition. Sleep latency is the amount of time it takes you to fall asleep. So, after they floated, on average, they fell asleep in 15 minutes versus 20 minutes in the control trial, and this was associated with a small effect size in favour of the float condition. Total sleep time, 6 hours 43 after float, 6 hours 31 after control. So, not great sleeps, they're not very long sleeps. This was associated with a small effect size, again, in favour of float. Sleep efficiency is the amount of time spent sleeping divided by the time spent in bed, and that was 90 after float, 86 after control. Again, associated with a small effect size. Waiso is wake after sleep onset, so once you actually fall asleep, how much time do you spend awake during the night? So, 20 minutes for float and 29 for control. Again, small effect size. Next two ones I won't go through, but awakenings per hour and wake episodes also associated with small effect sizes in favour of float. And then this one here, which was almost statistically significant, mean wake duration. This is every time that they woke up during the night, what was the mean duration that they would actually stay awake for? 5.4 minutes for float and 7.4 for control. So, some pretty good findings for float in terms of enhancing sleep there. So, let's have a look at muscle saunas. So, this was another really good finding for the float group. So, what we have here is our 1 to 10 scale of muscle saunas. So, we have the different time points. So, pre-exercise, post-exercise, post-recovery. So, that's immediately post-recovery. So, after the float or the control, 12 hours post. So, that's the next morning, and then 24 hours post. So, same with all of the figures that I'm going to show you. They're the same layout. So, the green line refers to the float condition, and the black line refers to the control condition. Now, these symbols up here, the purple ones, they just refer to where the significant differences between groups occurred and at what time points. So, as you can see here for muscle saunas, significant differences between groups, floating and droll groups at all time points. And these were associated with moderate to large effect sizes. So, lower muscle saunas after float. Okay, so, physical fatigue followed us pretty similar profile, maybe not as significant as the muscle saunas measures, but we did have a significant difference between float and control at 12 hours post. So, this was the pressure to pain algometer. The three muscle groups that were used for this were the vestus medialis, the vestus lateralis and the gastrocnemius. All three showed the same results pretty much. So, I'm just going to show you the vestus lateralis results here. So, we had a significant difference between control and float for having a higher pressure to pain threshold after the float condition. So, that's a good finding, right? So, the green here shows that at 12 hours post, so when they came back the next morning after they had done their float and then went to bed, came back, they had a higher pressure to pain threshold. The isometric mid-thigh pool, this was not statistically significant in terms of the differences between the trials, but there was a small effect size in favour of float the next morning. In terms of sprint performance, so on the left here we have 15 metre sprint time. We also have five and 10 metre splits, but I thought I'd just show you the 15 metre splits. And we saw a significant difference between control and float again in favour of float running faster sprint times the next morning here, which was associated with a small effect size. In terms of the repeated sprint, so this is the total time it took them to run three 15 metre sprints, was not significant, but a small effect size again in favour of the float condition. Counter-movement jump performance, we had a significant difference here between groups, again in favour of the float condition. So, what is the summary, I guess, of this research? I think you've all seen it there, there's some really positive results in there, but let's just talk through each one what we actually sort of found. So, in terms of the cortisol, we don't know. At the moment, we don't really know. So, there was a significant reduction pre-to-post in the float trial, but that difference was not significantly different between the two trials. Sleep, we'll give that the thumbs up because we saw some pretty good findings there, while there was only a significant difference in the perceived sleep quality. There were some pretty good effect sizes for things like sleep latency, total sleep time, sleep efficiency, wake after sleep onset, and so on and so forth. So, some good findings there. In terms of muscle soreness and fatigue, again, this is probably the most significant findings that we found in this study. Significant reduction in muscle soreness immediately post 12 hours post and 24 hours post in the float trial when compared to the control trial and in physical fatigue, we had a significant difference 12 hours post. We also saw significant increases in the pressure to pain threshold following the float trial compared to the control. In terms of the sprint or the speed, we saw a significant reduction in 10 and 15 meter split times with moderate effect sizes, 12 hours post. Strength, we don't really know. There was a small effect size in favour of the float trial, but this was not significant. In power, there was a significant increase in counter-movement jump performance, 12 hours post in the float trial compared to control. So, what's next? I think this work that we've just finished and hopefully will be published soon is really giving us an appetite to do some more work and look at some other questions in this space. I think the two studies that I presented today were both acute floats, looking at what happens after one off sort of float. It would be really interesting to have a look at the chronic use of float in these elite athletes. So, having a look at, perhaps floating multiple times a week over multiple weeks and we'd really like to look at the physiological and the physical adaptations that might come with that. Game day floating is something else that I'm really interested in and that's both pre-match or pre-game and post. Often in team sports and certainly the team sports that I work with, on game day, it's really common for them to have a nap. So, have a sort of a one hour nap in the middle of the day. Sometimes that's just to kill the sort of boredom while they're waiting for their game or that sort of thing or just even to catch up on lost sleep throughout the week. So, I think perhaps if we looked at float in that setting of doing a game day float around midday, that'd be really interesting to look at what happens to subsequent performance. But also post game. And we've published quite a lot of work looking at different team sports and what happens after the night of a match. And it's not uncommon for a lot of these athletes to fall asleep at a three or four a.m. the next morning. And that's due to a whole host of both physiological and psychological reasons, but we need to come up with ways that we can help there because they just get into this really bad spiral. If they're falling asleep at four a.m. the next morning after a game, that really reduces their recovery and the start of the week becomes really hard. And if they're playing week in, week out, or even if they're playing once every few days, that's a real issue. So, I think it'll be really interesting. And now that so many professional teams have float tanks in their locker rooms or in their facilities, actually looking at floating immediately post-match and seeing if that is bringing that bed time a little bit earlier. And because of, I guess, my interest in sleep, I'd be really interested to look at what happens post-float when we put some athletes in a sleep lab and we use full polysomnography to have a look at the sleep stages and phases and just see if there's any changes, I guess, in the architecture of their sleep following a float. And then I think another thing that we really need to do is compare float with other commonly used recovery strategies. So, things like cryotherapy and cold water immersion or ice baths, perhaps compression garments, things that athletes are routinely using. There has yet to be any sort of published studies that looks at float and compares it to some of these other recovery modalities, which will give us a really good idea of the efficacy, I guess, of float. So, just to finish some acknowledgements, I need to acknowledge my fantastic colleagues who have worked on these studies with me. Also Serenity Float Clinic and Sharl, who owns that. He's been incredibly accommodating with the research that we've been doing, so a huge thank you to him. And again, just to the float conference and to you for bearing with me and my husky voice. Thank you very much.