Siren (00:00)
I think that's a great injury prevention strategy is to combine different endurance modalities throughout a week to just have variations in movement.
Marjaana Rakai (00:03)
Mm-hmm.
Paul Warloski (00:34)
Hello and welcome to the Athletes Compass podcast where we navigate training, fitness and health for everyday athletes. Today we're sitting down with Siren Seiler-Vicken, a researcher and coach who's making waves in the world of Hyrox a fitness sport growing rapidly in popularity. Siren is the daughter of renowned sports exercise physiologist, Dr. Steven Seiler, and she's carved out her own niche.
translating
practical training wisdom. Her article performance determinants of Hyrox competition on the fast talk blog became the first scientific analysis of this rapidly growing sport. She's also worked with Athletica could help fine tune the Hyrox training platform here. Her journey is unique. She started building yearly training plans at just 13 years old.
That early love of structured goal setting evolved into a coaching philosophy centered on sustainability, identity, and the belief that you don't need to be in your best shape to start thinking and acting like an athlete. Today, she helps everyone from competitive Hyrox hopefuls to 60 year old grandmothers discover what it means to be part of the Athletica tribe. We'll dive into her Hyrox research, what the science actually tells us about balancing strength and endurance.
and her framework for building training programs that stick. Thank you so much for joining us here and we appreciate your presence.
Siren (02:02)
Thank you. Thank you for having me. It's fun to be able to talk to you today.
Paul Warloski (02:07)
Good, good. Siren, you were a highly successful endurance runner. How did you get into Hyrox in the first place?
Siren (02:16)
So I started actually training and doing sports at a very young age, but I did a lot of different sports, which is typical in Norway. We do different forms of sports like soccer, handball, gymnastics, and everything in between. I ultimately ended up
doing dance, focusing on dance and I competed nationally and internationally from age 9 to 19. So that was actually my primary sport for most of my young life. after, yeah, so after I decided to retire from dance, which is typical to do at a pretty young age, because it is, it was a highly acrobatic
Paul Warloski (02:55)
Wow.
Siren (03:10)
type dance genre, a lot of gymnastics elements, jumps, splits, backflips and more. But I always loved endurance training and kind of the physical part of the sport. So after I was done as a dancer, I wanted to take up running and I started just training more and longer distances just for fun at start. But then I...
competed in some local races and I got relatively good pretty quickly. And after a short time, I managed to establish myself at a national level and I have PRs of 160.02 in the half marathon and 5 34 in the 10K. ⁓ But then during the recent couple of years, I kind of
have shifted my focus more to strength and now Hyrox specifically because I felt like running alone wasn't really sustainable for me just because of the requirements when it comes to like body weight, et cetera, when you're running at a top high level. For me, it wasn't sustainable to stay at that low weight for an extended period of time.
while running my best time. So just building overall athleticism and being able to improve both strength and endurance is really fun, I think. And also a good way to build athleticism in a healthy way.
Paul Laursen (05:01)
Yeah, maybe actually just keep go a little deeper there for us here. what are the potential consequences if you went the other path and you were just focused on being a sole endurance runner for an extended period of time? What could happen if you're not careful?
Paul Warloski (05:01)
Mm.
Siren (05:22)
Yeah, so I think this is like very individual, but there are some obviously hard truths to being an endurance athlete and especially in like weight bearing sports. I started running pretty late and also because of that, I increased my volume quickly and the classic case of too much
too soon at too high intensity. So I had to kind of cross the line to understand where it was. And ultimately I developed the reds and some of the consequences of that, which was essentially just a result of wanting to perform at the top and do my best. ⁓
Paul Warloski (05:50)
and
Siren (06:18)
I found that being at a lighter weight as a distance runner in the 10K and half marathon is absolutely very beneficial to a certain extent. But when you pass that kind of, or it's like a knife's edge. if you go over it and stay there for too long, you suffer the health consequences down the road. And you may even perform.
very well when you're there, but you won't necessarily be healthy. And it's a hard truth. And some people tolerate it more than others. Me, I say I'm more a bit like my dad with broad shoulders and I look more like a rower. So for me, I really enjoy having the muscle mass and really trying to develop both those qualities.
and just feeling strong as well. Yeah.
Paul Laursen (07:20)
Awesome. think there's, Hyrox is just coming to us at a perfect time. You of course, one of the fastest growing sports in the world, targeted for the Olympics. But just with this overall, you know, a more holistic picture of the different components of, stress and adaptation that we want for a healthy existence. So it's, yeah, it's really cool. And you've come to the sport, I think, at the perfect time to.
too, Siren yeah, I really appreciate your contribution to it all.
Marjaana Rakai (07:50)
For those of us who are not familiar with Hyrox, could you give us a brief overview of the sport?
Siren (07:57)
Yeah, so it's basically an endurance race with runs and strength stations. So you run a total of eight kilometers. But if we include the part between runs and stations, which is called a rock zone, it's
ends up being more like nine kilometers. So it's a lot of running. And then there's eight exercise stations in between each run. So these are skiers, thousand meter skiers, sled push, sled pull, burpee, broad jumps, and rowing, lunges, farmers carry, and wall balls. Yeah.
Marjaana Rakai (08:46)
It sounds pretty brutal, but also fun in a way ⁓
Paul Laursen (08:46)
Coach.
Paul Warloski (08:46)
It sounds intense.
Siren (08:48)
Yeah.
It is.
It is really fun. It's like a very hard type of fun, but what I found when I started doing kind of simulation sessions or Hyrox inspired sessions as interval sessions or high intensity sessions, was like the time went by so much quicker and you're able to accumulate more volume at like threshold intensity and so on three to four.
depending on how you define those, but moderate to high intensity at least. Because you're changing up the modalities all of the time. So it's kind of a way to add a lot of variation to your HIIT sessions, I would say, in a fun way.
Marjaana Rakai (09:42)
I found that running, I picked up running again after having three kids. And I found like, you know, especially after having kids with little extra weight, it was so hard on my body. there was no Hyrox back then, but I found triathlon and I, I
Siren (09:53)
Mm.
Marjaana Rakai (10:11)
can relate to the, it's fun because it's not the same sport all over again. So with triathlon, I was really happy to get to the pool and do some, you know, some biking and not just run. So sounds like, like your transition from running to Hyrox was a little bit of the same, that it was the variation that was exciting.
Siren (10:37)
Yeah, absolutely. And also, when you like as a runner, ⁓ it's very easy to stop doing, like, stop jumping and, and, all of these different movements that that I was very used to as a dancer, like we used to do a lot of circuits and a lot of burpees actually, and, just using your body in different like
the directions, et cetera. When you're running, it's so monotonous that you kind of lose a little bit of that athleticism if you don't hold on to it by doing different movements and kind of challenging those qualities that you don't really need as a runner. So I find that...
Hyrox exactly that it just challenges the challenges, challenges you in many different ways from endurance to also strength, but also plyometrics or jumping ability and some mobility as well coordination.
Marjaana Rakai (11:49)
Yeah, so important. often, when we go down one sport path that we forget that variability of how we use our bodies.
Siren (12:00)
Yeah, yeah, it's true.
Paul Warloski (12:03)
here and let's let's get into the training of Hyrox a little bit you know one study ⁓ found that running accounts for about 60 % or more of a total Hyrox race time yet many athletes obsess about station times how should athletes actually balance their training emphasis
Siren (12:23)
Yeah, that's a good question and something I've tried to express in my articles for both Athletica and FasTalk. So just to be clear, I haven't done any experimental studies on hyrox myself and the research here is very limited. So it's essentially this one study by, I think it's Brandt et al from 2025.
where they actually look at the physiological determinants during a simulated hyrox race in recreational athletes. And yeah, in that study, running accounted for like 60 % of total duration of the race. And if we include the other two pure endurance modalities that are rowing and skierg it will end up as an even higher percentage that is
endurance based. so I think many people forget that running and being a decent runner and having a very strong aerobic engine is kind of the fundamental, determinant of hyrox. And if you only improve your running, you will actually improve your overall hyrox time the most I would say.
just because of the total duration that running alone accounts for.
Paul Laursen (13:56)
Mm-hmm. I can't remember if it was our article or the fast talk article, Siren but I'm pretty sure like you were quoting the average pace times of some of the winning males and females. And I forget what they were, but there were something like 320s, 320ks kind of thing that were close to running for some of these guys.
Siren (14:07)
Yeah.
Yeah, for these elite, some of the elite 15 male, the best ones, yeah. And for, I think, the women, it's probably like four-minute pace, like minute per kilometer or 345. But obviously, it depends because the split times that are shown on the Hyrox results websites, they will probably vary a little bit by course. And some...
Paul Laursen (14:30)
Yeah.
Siren (14:44)
Yeah, and also you don't really get the added distance from just passing other athletes as you run and the corners and also the rock zone that you have to run through. So the overall pace may actually be faster than what is shown in some of those results tables. if we just look at the total race duration and
split it by eight kilometers, it will end up something like that. And it's the fast pace for anyone, like to run a 20 kilometer eight times with eight stations in between, you have to be a pretty good runner before anything else. So for the men's pro, yeah.
Paul Laursen (15:19)
Yeah.
Paul Warloski (15:25)
Yeah.
Yeah.
Paul Laursen (15:36)
Yeah, no, it's nice. I just like how you
clarify that quite nicely. First thing you could kind of focus on if you were targeting that sport was really just to focus on your running and the means of doing that. Of course, all the other stations and stuff are important, endurance-based, technical, but if Hyrox is your passion, focus on what you can do for running. Unfortunately, again,
to the Athletica context, we certainly can help with that.
Paul Warloski (16:08)
You know, one of the things that, you one of the stations is the wall balls. And you talked about how that creates this massive physiological spike. You know, what makes wall balls so, so tough and how should training specifically address that?
Siren (16:25)
Yeah, I saw that they in this study from 2025, what was the exercise that elicited the highest RPE and also, I think heart rate, which to me is probably both the nature of the exercise itself because it's you're using your whole body, both the upper body and
Paul Warloski (16:38)
Mm-hmm.
Siren (16:51)
the lower body, huge muscle groups involved in this exercise. there's obviously there's a hundred repetitions. So that's one aspect of it. But the other one is that it's the final exercise. after like between, yeah, 60 to 90 plus minutes or whatever finish time you have, you're pretty cooked by the end of a Hyrox
Paul Laursen (17:03)
It's done.
Siren (17:17)
And I can confirm that the wall balls are horrible. I really wanted to give up, but I've never dropped out of a race or anything. when I did my, I think it was the very first Hyrox simulation, it was probably one of the...
Paul Laursen (17:20)
You
Marjaana Rakai (17:22)
you
Siren (17:45)
The most pain I've been in in a race was during those last wall balls, really just counting down. So yeah, I think it is both the nature of the exercise, but also that it is the final one and the accumulated fatigue is extreme. Your glycogen depleted. You're probably very, very hot, which also makes your heart rate rise.
because of the constricted blood flow and the lower stroke volume as you have to move more blood to the skin just to cool down. And these venues tend to be pretty hot as well. ⁓ Yeah. And also for anyone who has an endurance background and especially runners, we're not used to using our upper body, which is another aspect of it.
you're used to using your legs and the position where you're holding the hands above your head, repeated throws and squats. The arms really do fatigue because the blood is just flowing down as you raise them above your head as well. So I think there's a lot of factors involved here.
Paul Warloski (19:06)
So the wall ball is above your head, you have to catch it above your head or do you catch it, you know, chest high?
Siren (19:11)
No,
yeah, you can catch it wherever you want, you have to ⁓ obviously hit the target. So you have to throw it up a certain height. It's 270 meter, 2.7 for female and three meters, I believe for male. I might be not 100 % correct here, but it's something like that. So you have to do a decently high throw as well. Yeah.
Paul Laursen (19:30)
Hmm.
Paul Warloski (19:35)
Mm
Marjaana Rakai (19:38)
Yeah, it's pretty high. Yeah.
Siren (19:40)
And also you have to hit the squat steps. So it's below parallel. And I think they're becoming stricter when it comes to these rules. So you can have a no rep.
Paul Laursen (19:52)
Yeah, so I was just going to say, so if
you do 2.5 meters on your throw, it counts for zero. Is that right? Yeah, can just imagine.
Siren (20:00)
Yeah, yeah, because you're actually
Marjaana Rakai (20:01)
Thank you.
Siren (20:03)
hitting the target. Yeah. So it counts. It's like an automatic counter. Yeah.
Paul Laursen (20:05)
Imagine like you
Marjaana Rakai (20:08)
Yeah.
And I think now that we're talking about the technical aspects, it's not just like doing, ⁓ I'm just gonna do walking lunges here. You have to, like there's technical requirements that you have to fulfill. And if you don't, that's a no rep. So it's, it's very demanding sport for sure.
Siren (20:33)
Yeah, yeah, it is. There are several rules and technical requirements involved in all of the exercises, which is a great thing because it makes it possible to actually standardize and compare athletes to each other because you, especially at the elite level, they're stricter when it comes to these rules. Whereas for recreational athletes, it's a little bit less strict, but
But there are always judges there. So you do get a punishment, like a time punishment if you do something incorrectly or don't go low enough or drop a sled length or run a lap too little, you get added time to your finish time. So you have to follow the rules for the format.
Marjaana Rakai (21:23)
Mm-hmm.
The broad jump, burpee broad jumps, those are also very, very brutal. women have to do what, 100 meters or 80 meters?
Siren (21:37)
Yeah. ⁓
No, it's the same. That exercise is standardized for both male and female and all the divisions. it's 80 meters of burpee broad jumps. you have to, ⁓ your chest has to hit the floor and you have to jump parallel. You can't take any steps in between.
Marjaana Rakai (21:48)
Okay.
Siren (22:07)
So yeah, that is a little brutal. 80 meters, it's a long way when you're all already fatigued.
Paul Warloski (22:13)
So that sled push and pull is another one, you know, but it's completed in a relatively short time, but it's got the heaviest load. Does this suggest that max strength is a little overrated for Hyrox and that muscular endurance matters more?
Siren (22:34)
Yeah, this is a good question and something I believe will be a topic of research, just athlete profiling and looking at the the elite and assess their strengths, the numbers and as well as endurance numbers, etc. But of course, in Hyrox, yeah, the loads are heavy, but they're manageable for most people. If you have a
done strength training before and you do not need an extreme high max strength number to be able to perform these exercises because there's a lot of repetition. So it's as you say, more local muscular endurance. But what from my perspective, having a high enough
strength ceiling, to put it that way, is very beneficial because to be able to do the exercises with ease at a lower relative percentage of your max, it's beneficial to have a relatively strong deadlift and squat. Because if not, you're essentially working very close to your maximum capacity.
It's the same with, for example, Vo2Max If your Vo2Max is very low and you're running during a hyrox, pushing everything you've got, you also have to run at a higher percentage of that, or you don't have enough as much wiggle room to put it that way. So your threshold range is very, very small. So I'd say it's kind of the same for both strength and endurance.
Paul Laursen (24:24)
Mm-hmm.
Siren (24:32)
Both of you want kind of the ceiling to be as high as possible. But when it comes to strength, it is highly tied to muscle mass. So of course, there might be diminishing returns if you are trying to put on a lot more muscle mass than what you actually need, because that is weight that you have to carry through the run.
And hyrox is a weight-bearing sport as well. So ⁓ you can get a lot stronger without adding muscle mass through neural factors than ⁓ just study training. So yeah, it's an interesting question and something we'll probably know more about as we go.
Paul Warloski (25:18)
Mm-hmm.
Paul Laursen (25:23)
Yeah, I like how you're kind of, you're weaving in and out of the various different, you know, demands of the sport and the effects of spending too much time on one component versus the other. And this is kind of, is nicely leading into where we start to think about planning and training, which, you know, again, You've been doing this since you've been 13, Siren so that's really cool.
Now, when you start to think about ⁓ periodization or planning for your average Hyrox athlete, obviously you've mentioned that running is important, but how do you start to weave in these?
you know, these Hyrox station simulations or movements or just strength by itself. Where do you start, where do you begin to start to plan this out?
Siren (26:25)
so personally, I, I have a simplistic philosophy when it comes to hyrox training, because my background is, the latest years in endurance and, especially running and distance running, but I also coach cyclists, triathletes, but it's, it's built on the
same underlying philosophy. So I do follow a polarized or pyramidal approach to training where most of the training is at low intensities or... Yeah, that's a good question. Yeah, I shouldn't really use the term polarized. No, but...
Paul Laursen (27:04)
Now, hold on, hold on, Siren. Where on earth did you get that idea from?
Paul Warloski (27:11)
You
Siren (27:19)
Yeah, my dad is Steven. He was actually my coach when I started running. So he taught me everything that I know, not about the training planning process, but the endurance or running training specifically. Yeah. So I have learned a lot from him. Absolutely. But I've also kind of put theory into practice myself as a runner.
Paul Warloski (27:45)
Hmm.
Paul Laursen (27:46)
Mm-hmm, for sure.
Siren (27:47)
So,
Paul Laursen (27:47)
Yeah.
Siren (27:48)
so, so I do, I believe the theory, but I also know kind of how it feels to train in a state of flow, if that makes sense to, to actually feel like you're, you're, you're absorbing the training and not just surviving it from week to week. So that's why I do put a lot of emphasis on just building that base of low intensity and.
And it's called zone one, zone two. Zone two has kind of become, I think, the proxy term for just low intensity. So in the five zone Norwegian Olympic Federation scale, we call this zone one. Essentially, it's just below 72 % of heart and max. Just a very easy, relaxing pace.
So I first have to know the level of the athlete, how much they're training. And if we're talking about a recreational athlete, the term polarization might not be as well suited because they're not necessarily doing that many sessions or hours per week. But we still want to kind of
⁓ build the base and add more low intensity training before adding a lot of high intensity. It's this pyramid analogy or you first add frequency, then duration and then intensity. And if their goal is to progress over time and actually build up the volume, then this is a very smart approach and also learning what it feels like.
to train at a low intensity and then being able to push during the hard days or threshold sessions and with good quality and also recovering from these and absorbing the training from week to week. So first, I think of this endurance base, how to add the running, build up the running volume, the distribution of low and high intensity.
Of course, for a Hyrox athlete, the strength component is also very important. And during the base phase, I think in terms of basic strength training, fundamental strength training. So we may start at a higher rep range if the goal is to build some muscle mass. So eight to 10 rep range, ⁓ like an RPE of eight ish. ⁓
And then when it moves closer to competition, you reduce the repetitions, the load remains, and you're making the strength session less metabolic, if that makes sense. So the strength training, think it's important to keep that fundament. ⁓
Paul Warloski (31:02)
.
Siren (31:07)
in place throughout the season. So it's not like something you do for a few weeks and then you start only doing specific work. You have to, if you don't use it, you lose it. So it's hard to be too strong in hyrox I think, when you're doing a high volume of endurance. So just combining endurance training with basic strength. And then when you are going closer,
to competition you add in these specific sessions. For example, hyrox simulation style workouts once a week, some cross-fit inspired sessions, like as many rounds as possible type stuff sessions that are more focused on anaerobic capacity and just lactate clearance or tolerance. And you kind of just
use these three, four different types of workouts together, but not necessarily always at the same time. If that makes sense, because it's very easy for the training to be very intense if you're doing a lot of specific sessions and thresholds and strength and it quickly...
Paul Laursen (32:12)
you
Love it. I love it.
Marjaana Rakai (32:26)
Mm-hmm.
Siren (32:32)
becomes high stress every day.
Marjaana Rakai (32:35)
Can I ask you something that just that when you were talking about zones and zone one, zone two, and ⁓ do you get pushback from the athletes when you prescribe easy running or easy maybe it's even walking, right? Do you get pushback for zone one work on the training plan?
Paul Laursen (32:35)
Totally.
Siren (32:58)
Mm-hmm.
I wouldn't say pushback, but it's more about, of course, it is hard when you start running to stay at a low intensity because your green zone is very small. My dad even experienced this when moving from all cycling to training for Hyrox, running just felt hard. So for beginner athletes,
just teaching them what it feels like to stay at an easy intensity or a comfortable, relaxing intensity. might be during uphill walking, ⁓ jogging, alternating with walking. You have to really take a few steps back with pure beginners because easy or running by itself
feels hard by nature. But then over time, your heart rate will stay lower at a faster pace or yeah. So I wouldn't say pushback, but it's also about teaching people that the easy days should stay really easy and just relaxing and you're not supposed to hit a certain pace or anything.
Marjaana Rakai (34:25)
Mm-hmm.
Siren (34:25)
And
that might sometimes be problematic with some athletes who are more inclined to run a little bit faster or ⁓ maybe even more of a challenge in cycling because you don't have that mechanical load as you do in running. So I don't know about what your experience is coaching athletes here, running versus cycling.
Marjaana Rakai (34:52)
Yeah,
So there's kind of two layers here. lot of triathletes and runners and cyclists, even like runners, ⁓ they're a big base. I don't want to put everybody under the bus, but many, they think they look at their zone too
⁓ heart rate and they want to hit it like at the top of that zone too. Instead of when easy day is easy and aerobic base, it can be down all the way down to zone one, right? ⁓ So I find like the intensity control needs to start already there and not just when we're looking at the high intensity work. But the other thing was like,
Siren (35:17)
Yeah.
Yeah.
Marjaana Rakai (35:45)
People come to Hyrox format from endurance or they might be doing F45 strength sessions or they might have done CrossFit and now they're looking for another sport. So they are very used to that high intensity, let's go 45 minutes all out. Right? So that's why I was asking like, ⁓ do you have to control their intensity?
to keep it at that super low level, around 70 % of heart rate max or even lower. like, cause it's so easy to go to that like zone three or even higher.
Siren (36:27)
Yeah.
Yeah. So what I find in running especially is that when the volume goes up and you're hitting a yeah, eight hours plus per week and you're doing quality sessions, accumulate a solid amount of time in zone three to four or just up to 90 % of heart and max. Then the day after you feel like going easy.
So I think it becomes easier to manage this intensity and quote, polarize the days as you get more experience, but also add more volume to your training. Because you feel your body tells you, need to go easy today. I need to recover because ⁓ a threshold session or
Marjaana Rakai (37:10)
Mm-hmm.
Mm-hmm.
Siren (37:31)
moderate to high intensity session, 40 to 60 minutes duration that will cost you quite a lot and you will feel it the next day. And that is what I find with higher level athletes is that it kind of, it happens naturally after a while.
Paul Laursen (37:44)
Mm-hmm.
Marjaana Rakai (37:47)
Yeah.
Yeah.
Paul Laursen (37:51)
Yeah, I think, mean, MJ even has personal experience where she didn't always feel that, right? She kind of, you know, I think she's worked on her feel and, but I think you used to sort of think MJ that, you know, training always had to sort of had to be kind of hard, right? And yeah, if it wasn't hard, you weren't having a workout, right? It's the old no pain. It's the, I mean, your dad says it all the time, right? Like it's the no pain, no gain philosophy, which is.
Siren (37:57)
Mm.
Marjaana Rakai (38:06)
yeah, always. Yeah.
Siren (38:07)
Yeah.
No.
Paul Laursen (38:19)
rampant around the world, but we don't believe that's the best road to Rome. And I know you agree, Siren, because you just outlined your philosophy. ⁓
Siren (38:28)
Yeah, yeah, I do. I
do agree. And it is probably individuals as well how how much intensity we tolerate, I think. ⁓ Like when I used to compete in running a train, 120 kilometers per week, I had around 90 percent of my total time was at low intensity.
Paul Warloski (38:56)
Hmm
Siren (38:56)
So and that is that's quite a high volume below LT1. ⁓ But that was what I could tolerate because when we look at the total time I also did an hour to an hour and a half, zone three, zone four, sometimes zone five per week. Right. So and that's quite a lot too. But it's just
When you increase your volume, you do it by adding more low intensity because it's easier to recover from and you get a good stimuli from that. Whereas for high intensity, you have this kind of negative feedback loop. So more is not always better.
Marjaana Rakai (39:48)
So for athletes who maybe come from CrossFit into hyrox and don't have their aerobic base from running, I would assume that they need to do a long base phase where they work on zone one, zone two, so that they are able to run ⁓
the Hyrox, eight, nine case total, efficiently and still perform on the stations or what is your experience there?
Siren (40:26)
Yeah, I definitely think we need to... When I think of hyrox, I look at the total duration of the race. For most people, it's 70 minutes plus. So it's like a half marathon or more in duration, where you're staying at moderate to very high intensities throughout...
Marjaana Rakai (40:46)
Mm-hmm.
Siren (40:53)
the entire race. So heart rate is typically even higher in in Hyrox for the same duration than it would be during a running race. Just that nature of the upper body, lower body combined exercises. Yeah, the nature of the format and the muscular component components involved. So just being able to run for 90 minutes and
having a solid running base will allow you to.
work more efficiently during the stations and also recover better from them, right? Because you're essentially sort of recovering during the runs because you're accumulating so much lactate during some of these stations. Heart rate goes through the roof. So when you're running, actually have to...
Marjaana Rakai (41:33)
Mm-hmm.
Paul Warloski (41:33)
Mm.
Siren (41:53)
to run at an intensity where you're able to clear some of this lactate. And that means that you have to stay at that LT2 or just below it. In my experience, my running pace during a hyrox is half to one kilometer per hour lower than I would have my second lactate threshold at during a treadmill lab assessment.
Marjaana Rakai (42:05)
Mm-hmm.
Mm-hmm. Yeah, because imagine like you sprint as hard as you can, that 1K, and then you show up to burpee pro jumps. No.
Siren (42:23)
So it's important.
Paul Warloski (42:31)
Thank
Siren (42:31)
Yeah, it doesn't work. It
really doesn't work.
Paul Laursen (42:37)
Yeah. So how do you, that's a really good, um, good, good question. Like where do you, where do you gauge? Like when, when you sort of line up those one case, even when you start, like where's your, where's your pacing feel? Siren when you're, when you're doing an event, I'm like, kind of like, where do you, you know, do you, do you go by, how do you go? How do you pace it? Do you go by field? Do you go by heart rate? Do you go by speed? Um, yeah. What are you thinking about?
Siren (42:38)
So.
yeah, that's a good question. So I think in hyrox your heart rate can be a good indicator from the start, but also not because there's so much nervous energy involved and, and you're probably kind of fired up. So only looking at heart rate.
you'll probably see it being harder than what you would like. ⁓
So I think kind of controlling your intensity by effort, how you feel, but also, and now I'm going to sound like my father, but also the breathing, how you breathe, just because it is actually a pretty good indicator throughout a hyrox. I experienced a little bit with that myself. When you're starting to hyperventilate, you know that you're cooking.
And the heart rate is zone five high, it's maxed out and there's no way back other than going sore. So definitely just listening to how you feel and the breathing and staying just below that ragged edge and not tipping over, not kind of blowing up during some of the first stations because you carry that fatigue with you.
throughout the rest of the race. ⁓ So it's definitely a pacing game and it is quite interesting how I think there's gonna be a lot of research on pacing strategies for Hyrox. I think definitely starting out conservatively the first few stations.
especially if it's some of your weaker stations. If the skierg is a weak station, you want to really hold back on that so you don't go into zone five on the second exercise or after the run because there's a lot left, which I did at one point. So yeah, just I think with experience and learning also.
Paul Laursen (45:24)
Yeah.
Siren (45:31)
what your strengths and weaknesses are, you'll get a better feel of how to pace your energy throughout the hyrox
Paul Laursen (45:43)
like, I don't know. I don't know if it's a cult or the phenomenon of Hyrox. I mean, this is one of the fastest growing sports. We can't believe the numbers that are coming to Athletica just to, you know, to sign up for Hyrox plans. And again, thank you, Siren for all your edits and whatnot that we're working on implementing. But I'm curious about the...
Paul Warloski (45:50)
Yeah.
Siren (45:58)
Mm.
Paul Laursen (46:05)
like the status of the sport itself, whether it's, is it moving towards being in an Olympic event? Is it still on the same rapid increase in interest? And then why is that? Why do you think this has just taken the world by storm?
Siren (46:24)
So I have to clarify that I'm not involved in any Committee or anything like that, but I have had some conversations with some of the leaders for the coach education and the research itself. And it's definitely their goal to reach the Olympics in 2032, if not 2036, that's clear.
The reason why I think it's gained so much interest from the general public and like across every level and to the elite is that it's a sport that's available to everyone. We're not looking at the costs directly, but the format and the exercises, you don't need a lot of technique. ⁓
such as, for example, CrossFit and also the format. It's standardized across every race across the world. So it's easy to compare. And I think it is a very exciting race to watch. Like if you watched some of the Elite 15 races on YouTube and similar, it's exciting because athletes are going head to head and there's constant
change of exercises and you're kind of you get into the race it's fun to watch and there's always something happening which I think is very suited for the Olympics for example just because people want to watch it and it's fun it's entertaining which is
a big part of it as well. But also it's very fun to do and you can do it as a father and daughter like me and my dad did without a very specific goal time or you can try to reach a sub 60 minute hyrox as an elite athlete. So that's why I think it's gained so much interest and
Paul Laursen (48:23)
Yeah.
Siren (48:50)
And I think it's a very positive environment. I think also the combination of strength and endurance and that there's no one body type needed here is a big part of it. That you see athletes of different body compositions, some more strength-based, others more ⁓ endurance-based, and they perform equally as
as well. So that's another aspect of it. It's very inclusive.
Paul Laursen (49:25)
Wow, what a great answer. That's awesome. And it makes perfect sense.
Paul Warloski (49:29)
Yeah.
Siren (49:30)
if you have something special.
Marjaana Rakai (49:30)
I think one thing that people
wonder is how do you combine both strength work and endurance work? Like how should you schedule it across the week or across the day if you do two sessions?
Paul Warloski (49:36)
Yeah.
Siren (49:39)
Yeah, that's a good,
Yeah, if we're talking about kind of the concurrent training effect or the interference effect, that's obviously a real thing. There's some molecular signaling pathways that inhibit one another for strength and endurance stimuli. So AMPK and the mTOR complex for strength. But also, if you do
endurance session or a long ride or a long run and you're supposed to do a strength session after with full mobilization that's very hard and you're not really able to execute very well and you won't get a lot out of that strength session right because you're energy depleted ⁓ you're not you're not able to really fire so for athletes training high volumes I always
tell them to try to split up the strength in their own sessions by six hours or more. ⁓ Often, yeah, five to six hours is typically like what I prescribe. Of course, if more, that's better. But just to make sure that they're rested and refueled for that next session and also prioritizing the
most important session of the day as the first session. Personally, for hyrax, for example, or where you're trying to actually get something out of those strength sessions, I think it's smart to schedule that first, as the first one of the day, because you have to be turned on and ready during that session, whereas an easy run, for example, you can turn off your brain and
and just kind of go or an easy ride or... ⁓ So splitting up those two very different stimuli, ⁓ I think is important throughout the week and also having enough easy time between hard days. So I typically prescribe two low intensity days between two hit sessions or threshold sessions.
And something which has become increasingly popular throughout the years is double threshold training. If you've heard of that, you probably have. It's become kind of this phenomenon and also what I'm doing my, or what I did my master's project on, double threshold training and trained runners looking at stress responses, kind of recovery ability.
Paul Laursen (52:16)
Mm-hmm.
Paul Warloski (52:26)
Mm.
Siren (52:35)
But I do find that when you want to take that next step and build up the intensity and already you have high volume of training throughout the week, doing two threshold sessions in one day is beneficial because then you can have that next day as a fully easy day instead of adding another day to the week. then it ends up being easy or
Paul Warloski (52:50)
Mm.
Siren (53:04)
two hard days in a row or, and that really doesn't work. So I find that it's a good strategy I've used now on one of my hyrox athletes who's training towards sub 60, ⁓ trying to improve his running even more. And this really works for him just to add that extra volume of moderate to high intensity running intervals.
You can also combine modalities, which is great in Hyrox. then it's even easier to recover between if you do, for example, a row threshold session in the morning and then a run threshold in the afternoon or vice versa, for example. And then just filling in the remainder of the days with low intensity, ERG work, running work, filling up the volume of running gradually, and supplementing with other endurance modalities.
Marjaana Rakai (53:34)
Mm-hmm.
Siren (54:03)
which is so great in Hyrox because you can actually, you can do that and it has a direct effect on your sport. Whereas in running, we kind of view it as cross training and it's typically viewed together with injury. And so I think that's a great injury prevention strategy is to combine different endurance modalities throughout a week to just have variations in movement.
Marjaana Rakai (54:26)
Mm-hmm.
Yeah, I was gonna ask you if you use rowing or ski or ⁓ not just as a station but as an aerobic base building.
Paul Laursen (54:36)
cycling.
Siren (54:41)
Yeah, absolutely. yeah, ⁓ I do. ⁓ I tend like, you can do it, of course, in different ways. But what I find if you combine strength and endurance on the same day, it's smart to not train the same muscle groups in those two modalities. So for example, you have lower body strength in the morning and then you do erg work.
Marjaana Rakai (54:43)
or threshold.
Siren (55:11)
in the afternoon. ⁓ That's one thing I try to do is to put the ergs and the strength sessions together rather than running in strength because those two do not go hand in hand as well. And it's good to be able to separate the...
The muscle groups used for example, upper body strength and cycling in the afternoon is also a possibility. Yeah.
Paul Laursen (55:46)
Mm-hmm.
Marjaana Rakai (55:47)
Super smart.
Paul Warloski (55:50)
Siren, where can people reach you to find out more about you and your coaching?
Siren (55:56)
⁓ so I'm on Instagram, Siren Seiler I believe. And also my website, Siren Seiler coaching, So they can find the contact details there. ⁓ yeah. And my, my mail, but that's on the website or the contact form.
Paul Laursen (56:18)
Perfect. Siren, you're a legend and ⁓ so impressed of what you're doing. ⁓ And what's next for you? Are you considering doing your PhD? I know you finished your master's. Congrats on the exceptional paper on that, which relates to the different polarization models. And ⁓ I'm using that in my own writing. ⁓ It's my go-to.
Paul Warloski (56:18)
Excellent.
Marjaana Rakai (56:18)
Amazing.
Siren (56:22)
No. ⁓
Thank
Paul Laursen (56:48)
reference when I'm looking at polarization. congratulations on that. What's next for you in the academic field? And of course, we know you're doing with coaching.
Siren (56:58)
Yeah, my goal is obviously to do a PhD or maybe not obviously, that is definitely my goal. And I've had some exciting conversations with some people at the top of hyrox which probably I shouldn't like say out too loud, but we're having a meeting with my supervisor, my master's supervisor now and some of these.
who are responsible for the research development and ⁓ the hyrox Academy next or a couple of weeks. So we're talking about some potential collaboration there. ⁓ the main issue is obviously funding when it comes to PhDs. There's not a lot of internal or money.
for performance-based exercise studies. It's more health that's prioritized at our university at least. So that's the main kind of challenge, often having to get some external funding, et cetera. But I'm going to work on that. So the goal is a PhD and just keeping in with the academic.
my professors and establishing connections there.
Paul Laursen (58:32)
Perfect, perfect. Well, I'm sure you will navigate it because, yeah, there's, this is certainly, and it makes perfect sense that you're having a look at that, at the area that we've talked about here because you're a real leader in it and you not just, you don't just talk about it, but you also, you you walk the walk as well. So that's, you know, impressive and the way it should be. So congrats on all the work that you've done, Siren, and we'll continue to do in the future. We're honoured to be associated with you.
Siren (58:52)
He
Paul Laursen (59:01)
And thank you for all your help on the Athletica Hyrox plans.
Siren (59:07)
Thank you very much to you. I don't feel like an expert or anything, but I am just really eager to learn. also, as you say, I like to feel things on my own body and not just talk about it. So I'm trying to combine the theory and the practice and learn from my mistakes and help other people not make them.
Paul Laursen (59:37)
That's how it's done. We all do it. We continue to do it today, but that's how we all learn together. That's part of the process. 100%.
Siren (59:38)
Yeah, yeah, yeah, I still do. Thank
you so much for having me.
Paul Warloski (59:47)
Well, thank you for.
Yeah, thank you for joining us. Thanks for listening today to the Athletes Compass podcast. Take a moment now, subscribe, share, and let's keep navigating this endurance adventure together. Improve your training with the science based training platform, Athletica, and join the conversation at the Athletica Forum for Siren Seiler-Vicken, Marjaana Rakai, and Dr. Paul Laursen
Paul Laursen (59:49)
pleasure.
Siren (59:51)
It's been really fun.
Paul Warloski (1:00:11)
I'm Paul Warloski and this has been the Athletes Compass Podcast. Thank you so much for listening.