GryphonCAST Episode 8 Transcript
Speakers: Michael Lim, Lawrence Spriet, Danielle Nyman
Michael Lim
Although the next winter Olympics are four years away, knock on wood, athletes around the world are already hard at work training for their next appearance on the world stage. At the Olympic level, the slightest change of performance can mean the difference in making it to the podium. While some athletes have taken to performing prevent event rituals, or wearing lucky socks, new research suggests you should be more concerned with what you're swishing in your mouth. Open your ears and mind and let's chat about that. Welcome to GryphonCAST a podcast where we casually chat about science coming out the College of Biological Science at the University of Guelph and how their work can affect lives around the world. I'm your host, Michael Lim. With me today for a special dual guest episode is Dr. Lawrence Spriet and PhD student Danielle Nyman. We'll be chatting about their recent study looking at how male ice hockey players improve their on ice performance by rinsing their mouths with some carbs. So welcome, Lawrence. Welcome, Danny. [cross talk] Thank you. Thanks for having us. So, introduce yourself. Can you briefly describe what your research is about? Or I guess what piques your interest when you're talking about human health and nutritional sciences?
Lawrence Spriet
Okay, well, I'll start. I recently retired but I've been a professor in the Human Health and Nutritional Sciences for 36 years, and I guess I've been very interested in things that you might consider to be lifestyle: so movement, exercise, and nutrition. And for most of my career, I did a lot of work studying or examining the regulation of metabolism or how we take fuels and make energy (mainly in the skeletal muscles) that allow us to move. Another arm of my work has always been taking that information and trying to apply it to sport and a lot of times, elite sport. Because clearly, elite athletes are pushing the limits in terms of what muscles can do, the nutrition they require and so forth. And that's really what kind of led to this this line of work that Danielle did.
Danielle Nyman
Yeah, and pretty similar to Lawrence. I definitely haven't been at it for 36 years, but I started volunteering with Lawrence's lab in the third year of my undergrad. And that really built on my fascination of just like how we can manipulate the human body to improve performance, whether that's like acute with like nutritional strategies like we're going to talk about today, or more chronic exercise. I'm really interested in how we can kind of push the limits of human performance. So, that's how I got started and then that spiraled into an MSc and then now I'm doing my PhD in the field as well.
Michael Lim
That's exciting. So, for this particular study, working in, I guess I talked to performance. Was it like a joint effort and deciding what you want to study and how you would study it?
Danielle Nyman
Yeah, so I've always loved ice hockey, like I grew up playing it. And how I started volunteering with Lawrence's lab was his Master's student came to our class to recruit hockey players for his study at the time. But it required male triple A players and I'm neither of those things. So, I asked if I could volunteer. So, that was a goaltender dehydration and thermoregulation study. I really enjoyed that. And then I got involved myself with my fourth year project, which was actually an athlete monitoring project with the Gryphon Women's Rugby Team. So, then my thesis research combined both those ideas where we're looking at some nutritional strategies in hockey, but I really want to bring in like that athlete monitoring component. So, that's how I came up with this research idea, but Lawrence is the number one hockey guy around town. So, that did have a big part of it and I started to really like it.
Lawrence Spriet
Yes, I guess it goes back quite a ways - actually back to about 2005. Because I was actually approached to start doing start doing sweat testing, if you will, with elite hockey players. Basically, measuring how much elite ice hockey players sweat and whether they do a good job of putting the fluid back into their body. And over the last 10 or 15 years, I would say that it's commonplace now for ice hockey players, whether they're elite or not to be rehydrating on the bench all the time. And whereas 15 years ago, when we tested, half of the players would let themselves get more than 2% of their body mass lost during hockey. And in most stop and go sports, if you lose 2% of your body mass, your performance starts to decrease. So, we try to prevent that. But now when we test teams, sometimes none of them get near that. So, I always joke with my students that we have worked ourselves out of a job because the maintenance of hydration during ice hockey, you know for the elites is pretty much there now and the new challenge is trying to teach them about the value of carbohydrate. Because carbohydrate is really the primary fuel you use in a sport like hockey. So, that's sort of how it evolved.
Michael Lim
So, speaking of kind of advancing the research and looking at how ice hockey players are hydrating themselves, you recently published a study titled “Carbohydrate Mouth-Rinsing Improves Overtime Physical Performance in Male Ice Hockey Players During On-Ice Scrimmages”. So to begin, for audience members, could you describe some of these terms like overtime and scrimmage describing what they mean in terms of activity in the sport?
Lawrence Spriet
Sure. So, I think most people realize that hockey is played over 20 minutes of stop time, where the shifts are quite short, but very intense. In the National Hockey League right now, the overtime is time tacked on to the end of the game if it's a tie. They are using a version of overtime where it's three on three players not five on five and they play for 5 minutes and if they don't score then they have an actual shootout. Which is basically each team gets to take a penalty shot on the other team and at the end of three rounds or four rounds or however many it takes, whoever has the most goals wins the game. The other term that we use a lot in the paper is scrimmage. Basically, what scrimmage is, is sort of an unofficial game where you're playing against each other. And in the case of Danielle’s study, mainly because of the COVID restrictions, we played three on three hockey. So, it was simulating the NHL regular season overtime. And so that's why we didn't call it a game we called it a scrimmage.
Michael Lim
Is there anything you want to and onto that Danielle?
Danielle Nyman
I'm not sure if Lawrence mentioned, but hockey is unique in that overtime is a winner take all most commonly referred to as a sudden death format where when you score that's when the game ends. So, I know in certain sports, you either get extra time and even if a team scores they’ll continue to run that time out. But in hockey, there is no second chance and once you score that goal, the game's done and that team wins. So that's like why we put so much emphasis on the performance in overtime it really make a huge difference - not only on that one game but in a playoff series or in season those overtime wins can really start to add up.
Michael Lim
So, you kind of touched on a little bit but depending on the flow of the game, obviously these ice hockey players when these short 15-20 minute rounds essentially are facing moments of high intensity activity. So, you know rapidly accelerating, breaking, grappling each other, body contact. So although human bodies can use a variety of different types of energy sources, like say fat. What makes carbohydrates so beneficial for these types of high intensity activities?
Lawrence Spriet
Well, that's a great question and there's a couple key things about carbohydrate that people need to understand and that is that you can mobilize carbohydrate and make energy from carbohydrate much, much quicker than you can from let's say fat or even protein. The other big advantage of carbohydrate is essentially when we talk about making energy or adenosine triphosphate ATP, there's really two ways you can do it. You can do it by combining with oxygen and producing ATP in the mitochondria of your cells and we refer to that as aerobic metabolism or making energy with oxygen. And that has quite a high capacity but it's a little bit slow to turn on – it might take 30-60 seconds for you to reach where you want to be when you start exercising. But the cool thing about carbohydrate is that you can also use it to make energy without oxygen or the so-called anaerobic metabolism. And we associate anaerobic metabolism by in large with the ability to make ballistic quick, powerful movements or sprinting. So, if I'm standing on the ice and I decide to start to skate as fast as I can, for the first few seconds, the majority of the energy will come from anaerobic metabolism because aerobic metabolism takes a bit of time to turn on. You know the bottom line is carbohydrate is your high intensity energy whether you're working aerobically, or anaerobically, or most commonly with a little bit of both.
Michael Lim
So, in your study’s background information introducing the kind of work has been done previously, you mentioned that carbohydrate solutions have previously shown to improve performance and decrease fatigue in ice hockey players. So, can you describe kind of what was the mindset when you started shifting between consuming the carbohydrate solutions versus just rinsing it in your mouth?
Danielle Nyman
Yeah, I'll take this one. So, the basis for my research was three previous studies from the Spriet lab and like you mentioned Michael, they did show improved performance, and that included things like increased voluntary work, increased time at high effort, increased speeds that we saw in ice hockey. But what was unique about these studies was that they had an ingestion condition that was a Carbohydrate Electrolyte Solution (CES). Most people know that as a sports drink. So, the players would ingest that and hydrate with it. But in these studies the second condition was actually a no fluid dehydration trial. So, the participants were purposely less to mild dehydration essentially and from the findings of a studies, it kind of left this gap of where the performance was coming from. There was a performance improvement with the CES but we didn't know if a performance enhancement was due to actually hydration with the CES, whether it was ingestion of carbohydrate from that solution, whether it was oral exposure to that carbohydrate, or whether it was some combination of these factors. So, then my research wanted to build on those studies and look at everybody being hydrated, and then just introduce one of those factors, which in this case was oral exposure to carbohydrate, and seeing if that had any effect on performance.
Michael Lim
So in your study, you use a specific brand of sports drink name redacted for the sake of being fair to all sports drinks out there for both the carbohydrate rinse and the placebo rinse with the placebo being a zero calorie version. So, do you think can we use a different sports drink or maybe a different flavor for example, would there have been different results? And what about doing something say if it just juice or like a simple syrup or a honey drink that also has carbs and sugar in it?
Danielle Nyman
So in this study, we used our carbohydrate condition, which was a conventional sports drink. And then we also used a non-caloric version and this was a placebo so it looks the same and it tasted the exact same. And actually, I think it was out of 48 different questionnaires we had only five participants were able to correctly identify whether they had the carbohydrate or the placebo condition. I don't think we would see any different effects with a different sports drink. Purely what's most important is actually the presence of carbohydrate which I think we mentioned a little earlier, but that's what matters. It's not the sweet taste. So, in those early studies, when they had participants with something like sucralose, for example, which is the conventional non-caloric sweetener used in the placebo sports drink. It doesn't have any effect, similar to the carbohydrate condition on the brain. As long as the other sports drinks - other brands had carbohydrate, it wouldn't matter on the flavour, the sweetness, color, consistency, most of that wouldn't matter it was just the pure presence of the carbohydrate itself. That being said, there is an ideal concentration for a sports drink, and that's 6% carbohydrate. So, I think if you want to take like a separate approach and try and make your own sports drink like you mentioned with like syrup or honey, again, it would have to be the presence of fat carbohydrates to have a positive impact. And then too, you want to be careful of the quantity of carbohydrate you're putting in that fluid.
Michael Lim
As we kind of hinted at throughout our discussion so far, it certainly reveals that players with carbohydrate rinses performed better during overtime, in terms of factors like increased peak speed. Was there a particular variable that really stood out to you that really highlighted “Yes, rinsing is the way forward for increased performance”?
Lawrence Spriet
I think for me, the ability to reach peak speed more often is really critical. I mean, the trouble with ice hockey, of course, is there's no one variable that's going to predict success other than goals scored. But you know, it's a combination of different things and the fact that they were able to reach peak speed more often and maintain it. And maybe secondly, the fact that they rated the exercise the same as they did in the non-carbohydrate trial. Even though in the carbohydrate trial they were covering more distance and getting more work done. So, they were able to if you will stay at it.
Danielle Nyman
I do agree with Lawrence and something that I also found really cool from our results in overtime was that when you mouth rinse with carbohydrate, you had significantly increased distance at high intensity speed. So, with our local positioning system we were able to track speed in six different categories. So, everything from like a very slow skate up into a sprint. The distance at high intensity speed included those top two speed zones, which is about 80% and above of your speed. And seeing that in that 80% of your top speed when you mouth rinse with carbohydrate, you're able to skate a greater distance. And what was really neat about that in the overtime period was that the players only had three shifts in overtime. But we saw them skates up to I believe it was 40 to 50 more meters and that very high speed zone. So, the fact that they were able to accumulate that much additional distance in a very short time span that was impressive to me, especially in a game like ice hockey where a lot of your performance and the gameplay depends on your ability to isolate yourself, get yourself room, give yourself more time. So, the fact that the carbohydrate individuals were able to skate more, perhaps provide themselves with more space, that was a signal to me that this could be really beneficial in a real game setting.
Lawrence Spriet
Yeah, and I think Michael, one of the things that people wouldn't necessarily realize by reading this study is that the rating of perceived exertion scores were really high. In other words, they were very tired. And with us being on the ice with them and both Danielle and I playing hockey we know exactly you know how that feels and is basically your body is saying “Alright, that's enough. Let's slow down here. Let's pack it in” type thing, but I think the combination of the competition and just the right fueling makes a big difference in terms of what you're able to accomplish in the overtime.
Michael Lim
So, would you say it's something like the people who are consuming or rather who did carbohydrate rinses are less exhausted or they just feel like they're less exhausted?
Lawrence Spriet
Well, it's probably the latter. It's that regardless of the signals you're getting from your muscles that you know, are associated with fatigue, all of these things are feeding back to your brain and a lot of athletes say “I don't feel very perky. I feel lethargic. You know, it's really hard to push I can't focus”. So, I think that's where it comes that you're kind of ignoring some of these peripheral signals. That's a big, big thing. And I think it's even more important in the elite field where every athlete is properly prepared. They're well trained. They've got their nutrition to a peak. They're very competitive. So, these are the types of small things that make a difference in a person's performance.
Michael Lim
So, we touched upon it a little bit, but in your study you partially credit the importance of development of technology to do these kind of team player sports tests, like Bluetooth heart rate monitors has been really important. How's this done previously, if you want to study team sports or was just not done, and you'd expect more incorporation technology like this in sports studies in the future?
Danielle Nyman
Lawrence, you were around before me so…
Lawrence Spriet
Yes, that's yeah, that's a thinly veiled shot at how old I am. And so, in the in the beginning, you know, most of these types of things were done by filming the games. And if you wanted to, you wanted to know how fast the players were going well, you needed a grid that you could apply over the playing surface, with the computer and you had to digitize basically things you know, every second or every, whatever. And it was extremely painful. And we did a study like that where we did all the digitizing looking at how much how much ice that they had skated and so forth. The advent of GPS technology really pushed everything forward like crazy. So and then all of a sudden, in the last few years, we've had this GPS technology be translated into indoor sports. So, we put 16 sensors around the arena, and they're picking up signals from a little sensor you're wearing on the back of your shoulder pads. So, we know where you are, how fast you were going and how much area you covered. The really cool thing is it can mean it can record number of contacts where you're hitting the boards or you're hitting another player. Unfortunately, you know, there's still things that can't be really measured like the grappling and pushing along the boards when you're trying to fight for the puck. Anybody whose played hockey, that is exhausting and yet, you've hardly moved at all. It's just - that's the way it is. So, that's another step that has to be taken into account. But I mean, I'm retired now but one of the things I feel badly about not having worked on more, is actually measuring the energy cost of playing hockey with a portable oxygen uptake system that goes over your face. A company has recently produced a face mask that actually measures the oxygen right in the face mask. And now they're working on measuring the carbon dioxide that's emitted, so that we can calculate what fuel is being used and so forth. But again, it's difficult to do that with a face mask on for an entire period where you can't drink and so forth. So, but I believe that's coming and there'll be forms of wearable technology that are very popular as well. So I think all of these things are coming. I'm not sure who will do them but somebody anyway. [cross talk]Right, Dani? Yeah, maybe Dani will.
Danielle Nyman
I would love to. Yeah, I was gonna say I really do believe we're at like the forefront of another wave in sports science of all this wearable technologies is really taking like pro sports, and even minor sports by storm, which I think is fantastic. It's unlike anything we could do in the lab where you really can measure people in a real world or a field setting. But I do believe there's some cautions that need to be taken. Right now we're in this phase where we have all this data, but we're still working on describing it and understanding what these numbers mean. So, I think it's just important to have that perspective. There's so much else that goes into sport, especially a team sport, the camaraderie and the respect between individuals the coaching. In hockey, something we'd like to call a hockey sense of just like knowing where the pucks going to be, knowing where your teammate is. So, the wearable technology is a really good tool. I think it's fantastic. And I'm really excited to see where it goes. But I do believe it's just one piece of the puzzle that we have to work with.
Michael Lim
If you could go back in time and change one thing about your study, what would it be and why?
Danielle Nyman
Ideally, if COVID hadn't hit, I would have liked this to replicate a real hockey game even more. So, we had to make a lot of adjustments based on public health protocols for like, how many people can even be in the arena. And based on that we had to downsize the game to three on three and we also played what was called small-sided. So that replicates the setup of the entire hockey rink, but it was played on about a third of the hockey rink instead. So, to have this be like most applicable to a real world situation, I think we already did a really good job, but by having like full ice, five on five would bump it to that next level. And I would like to replicate the overtime period as well of having with the three regulation periods. I would like to bump that overtime period down to five minutes instead, because that's what we see in the National Hockey League. And then to something else, would have been including more players. So, we're rotating two lines and our shifts were regulated to be two minutes long. And anybody who's playing hockey will tell you that is like an eternity to be on the ice. Even in the small area that's a little better it’s a little more manageable. But in an ideal world we would have included more players and then had these guys rotating like maybe every minute instead. And that's the main changes I would make. Although I was pretty happy with how it all pulled together.
Lawrence Spriet
Yeah, and I would agree with that. And I think that we're pretty fortunate because there's a few publications that have shown that in terms of skills and movements and things you can replicate five on five hockey with three and three hockey quite closely. But I think Danielle has covered all the major [crosstalk]
Michael Lim
… Something that might make you come back out of retirement to do another study the study?
Lawrence Spriet
[Laughter] Oh, I don't think I can do that! I can come back and watch but I don't want to have to organize.
Michael Lim
So, I have questions from social media and our first question is: In the lead up to a sports event, are there any diets or even specific foods or drinks you recommend avoiding? Alternatively, what do you recommend consuming?
Lawrence Spriet
Well, I can start with that and assuming that we're talking about an intermittent high intensity sport, then I think the primary thing you are worried about is carbohydrate. Typically, people don't eat a whole lot in the hour beforehand and you know, it wouldn't make sense to eat your protein or fat in that last hour because that takes quite a while to absorb into the body and you're not going to be using a lot of that as well. So, I would say you know, make sure that you have had adequate carbohydrate in the days and hours leading up to the event. And make sure that you're well hydrated.
Michael Lim
And for our last question. Is there a difference between changing your diet or nutrition intake to more healthy compared to trying to be more athletic or muscle building focused? For example: If I eat more protein in my diet, when I'm not working a lot is that still healthy?
Lawrence Spriet
Well, that's a difficult one. I think if you stick to the recommendations that are out there where it's about 50% carbohydrate, 15 to 20% protein and then 30% fat. That is a fairly healthy diet. One of the biggest problems isn’t so much about the constituents of the macronutrients but how much you're eating. Because let’s face it in North America, in Canada the biggest problem really is that we’re eating too much for the low levels of physical activity that we are involved in. So many Canadians hardly do any physical activity. So not surprisingly, you need very little food. And I read pretty interesting articles saying that if you go back 100 or 120 years, people ate just as much as we do now but they work physically much harder. So you know, obesity really wasn't a common thing. With respect to the diet for an athlete. You know, the first thing that has to happen for an athlete is they simply have to eat more because they're burning many more calories and even for people that are trying to put on muscle mass, the Western diet has a lot of protein in it. So typically, we are eating more protein than we normally would. And the recommendations protein for an average person 0.8 grams per kg body mass per day. Athletes need somewhere close to double that. But when you do a dietary record of an athlete eating a healthy diet, they're getting it because they're eating more food and with it comes more protein. So, but it's an interesting thing like I have to deal with this quite a bit where people you know, lately, the last few years, carbs are bad. Before that it was fat was bad. And it's really hard to convince athletes who hear this all the time that carbohydrates should be a major focus in their diets. And I tried to explain that carbs aren't really bad but the majority of us Canadians who are not very physically active are you could argue are eating too many carbs, are eating too much protein are getting too much fat. Because we're simply eating too much food because we don't need very much. But trying to convince an athlete that “yes, you may have to consume 4000 calories on a hard workout day and therefore it's a lot of carbohydrate, a lot of proteins etc. So, that’s the biggest dichotomy I find between athletes and just normal people that are struggling not to eat too much because they're not doing any physical activity. And I always tell people, if you like to eat, get on your bike ride around, walk, swim, you know hike, whatever, then you get to eat more. So anyway, that's my take [crosstalk] on things.
Danielle Nyman
Yeah, and Lawrence talked about every point I have went [laughter; crosstalk] on so I agree with that. So yeah, just be careful of the amount they eat, but recognizing that if you are an athlete, like you have to make adjustments. I'm usually in the positive side of things and also timing is important when you're talking about things such as protein where your body can only process and effectively use so much within an acute dose. So, just doing some reading of how frequently you should do that and usually the best advice would just be to have some protein in every meal and have a balance between carbohydrate, fat and protein.
Michael Lim
Do you have any final comments you want to make like your work or this study? And if there's only one thing you hope that are listeners take away from our chat. What do you hope it is?
Danielle Nyman
I just want listeners to know that carbs are not the enemy. We rely on them. We need them [Michael Lim: carbs are our friends]. Yeah, they're not bad for you. And they're especially important if you are an active individual. So, that would be the main takeaway that I want you to have.
Lawrence Spriet
Yeah, I would agree with that and simply say that I think sports science is in a really great place. We have new technology. I'm sure we'll get more new technology to really fine tune trying to optimize the scenario for athletes who are interested in becoming the best they can be.
Michael Lim
And I think on that note, that brings us to the end of today's podcast. A big thanks again to our guest Dr. Lawrence Spriet and Dani Nyman for joining us today. GryphonCAST is brought to you by me your host Michael Lim with editing assistance from Ian Smith. If you are hungering to learn about different science topics please check out SCRIBE Research Highlights. That’s SCRIBE, S-C-R-I-B-E Research Highlights on the University of Guelph website at uoguelph.ca or you can follow us on social media @UoGCBS.You can find us on Instagram, Twitter and Facebook.
Music in the podcast comes from upbeat.io with the details in the show notes. Until next time please stay curious.