This episode of The Athletes Compass Podcast explores essential training strategies for endurance athletes. Hosts Paul Warloski, Dr. Paul Laursen, and Marjaana Rakai tackle listener questions on topics like optimizing high-intensity interval training (HIIT), the benefits of workout variety, and managing fatigue effectively. They discuss the importance of consistency over intensity, the value of mental toughness, and practical tips for long indoor sessions. With actionable advice for runners, cyclists, and triathletes, this episode provides fresh perspectives on sustainable training approaches, from double run days to smarter endurance adaptations.

Key Episode Takeaways

• Incorporating alternative modes like cycling or rowing into HIIT can reduce injury risks while maintaining cardiovascular benefits.
• Consistency in training is more valuable than pushing to exhaustion; "leave two in the tank" is a winning philosophy.
• Splitting long workouts into multiple sessions can be an effective adaptation for busy schedules or indoor training challenges.
• Mental toughness, or "Finnish Sisu," plays a crucial role in endurance sports, particularly in long training sessions.
• Frequent, shorter runs often lead to better adaptations than occasional long runs, especially for marathon or triathlon prep.
• Brief excursions into higher training zones during endurance sessions are acceptable but should be minimized to avoid overtraining.
• Double run days amplify adaptive signaling, improving resilience and efficiency over time.

• Paul Warloski - Endurance, Strength Training, Yoga
• Marjaana Rakai - Tired Mom Runs - Where fitness meets motherhood.

Marjaana can do incredible four and five hour rides, but she's a maniac.

did you manage those long, long rides? mean, you did four and five hour rides.

Even six and a half.

Just Finnish Sisu. Mental strength.

Hahaha

a mystery. It's the willpower, I guess.

Hello and welcome to the Athletes Compass podcast where we navigate training, fitness and health for everyday athletes. Today we are listening to a bunch of questions from our listeners and our writers and our athletes and we want to help you try to figure out what is going on with your training. So if you have questions, please ask us. So the first one comes from Peter Jan Verica from Belgium. I want to train for an ultra

There's a lot there, Paul.

Hmm. Yeah, but it's, it's a, actually a really good question and I'll give you my, my two cents. So basically what, Peter is asking, Peter Yen's asking is like, you know, how can I sort of supplement, alternate exercise mode sessions to really, I almost target different areas of the body, to optimize performance. And I do this actually a lot with.

Mm-hmm.

One of the phenom young runners that I train here in Revelstoke, what we do, we've kind of come up to the realization that too much HIIT work is, you know, it can be really risky. There's an old adage in coaching with running is that "speed kills". And it's because it's just, you really like, it's all about intensity control, right? We hear that about in the Norwegian method.

And when you do HIIT using different exercise modes, such as cycling or such as rowing, they're less damaging from the eccentric phase. So that's the muscle lengthening phase. That's like, you know, remember that when you're running, you're actually doing like hops, you're like, you're actually like hopping repeatedly, repeatedly all the time. So just imagine, you know, you're always like just stand on your floor or

outside and just hop, hop, hop, you'll kind of, you'll very soon realize that these are, you know, eccentric, damaging contractions. So when you are, you know, doing HIIT work and sprinting, these are, they're really, they're quite taxing. So if we can deload that area, but still work on other areas of the body, like the central circulation, the heart and the lungs, we can still maximize our physiology, right? The delivery aspect.

of what we know is needed, right? So we can still work on the lungs, the heart, the transfer of that to the muscles, but have it being less risky. So Peter Yen, your idea is excellent and you can certainly swap up the HIIT running sessions with rowing sessions or cycling sessions or swimming sessions.

All are excellent alternatives because you're still going to be expanding the cardiac output, the central circulation and the delivery aspect, but being less risky on the musculoskeletal sort of strain and muscle damage. So that works really well with the runner that I was speaking about. She does them on the bike, but rowing is perfectly acceptable as well.

found when I was doing my Ironman training that the heat session on the run was a little too much. So I could have done maybe ski or rowing heat session, but I just dropped that.

running a heat session altogether.

now for sure.

How many days a week

can we replace that? mean, is it like twice a week? Is it still better to get at least one day a week of running HIIT to get that specific adaptation or does it matter?

I mean, context, right? Context is, so it really totally depends. So for example, with the runner I was speaking about, you know, when she is certainly in like cross country running mode, she's getting a, you know, she's going to actually do like a 5k race as part of school. And she does that every, they do that pretty much every week or have done that through every week through the last few months. So.

Yeah.

That's the, that's the high intensity session for her legs. And there's no other HIIT sessions during the week, except on the bike and everything else is just long, slow running. And that's, you know, that works for her. And this is the other problem actually with, especially with, certain athletes that just have so much aerobic power, is that they can just tear their legs off. And if their, legs aren't conditioned to being able to do that, they really can,

Yeah.

And I was basically giving him the lecture that in a room that you always have to have two days of rest between your HIIT sessions, right? And the old man puts up his hand in the classroom, right? And he said, well, with Walker, we did HIIT sessions just about every day. So he had built up the resilience to be able to kind of...

do that, right? So

a, we have actually an incredible tool in our disposal now with Athletica. We never know, this has never been available before, but if you're, if you're using wearables, you'll be able to see that on your workout reserve.

So don't let your workout reserve get to below, say, you know, too deep and below, below zero.

And if you do that, that's kind of like the context question. You have that context if you're regularly uploading. So be mindful of that. Because remember, the workout reserve is actually monitoring the maximal mean power or maximal mean pace in those high intensity bits or bandwidths. So it knows the length of time you've been doing at one minute.

repetitions or two minute repetitions or five minute repetitions. And yeah, so just if you've got the real time garment app, you are so at an advantage relative to others. And just be mindful, like when it gets down and starts getting into during your HIIT sessions down in around, you know, 10%, 5 % in negative territory, it's like really be mindful that that's enough.

So one of my athletes, Chris Collette asked a question that goes along with what you just said in a way. it was, I thought it would be a great question to bring to our discussion.

And she was asking like, well, why should I back off of intervals when I'm already a little fatigued? Why shouldn't I just push through an interval session?

even if it's already hard to meet those power targets. What's the physiology and the rationale behind that?

the general question, we're almost looking at the hit your target, walk away, leave two in the tank kind of philosophy versus the no pain, no gain philosophy, right? And we take the leave a couple in the chamber kind of philosophy. That's what we believe with Athletica. And the reason is, is because we know that

Consistency, and if I can put my academic hat on, consistency of cell signaling alongside of a balanced nervous system is the key training philosophy that we are in with both HIIT Science and Athletica it's just like, it's a targeted training approach. We know that consistency of training, the data is clear. If you are consistently training day in, day out, as much as you can.

and hitting those targets, right? You have to imagine your muscle cells, they are cells and they adapt. The DNA actually will transcribe RNA, which transcribes protein and makes you based on the signal that you are telling it to. So you're in that HIIT session, you're giving it a signal to adapt. so, well then Chris could kind of "Well then why don't I want to just keep that signal going?" And the answer is because, you can't.

You have a central nervous system that's there to protect you. And if you keep hitting that signal with the no pain, no gain philosophy, you break down the system. The system says, no, no, no, no, I can't do that anymore. it just, yeah, it rebels on us. And we can measure that, of course, in our heart rate variability marker, right? And yeah, so that's it. The method of consistently hitting that signal

the signaling, right? And specifically of the fast twitch muscle fibers in the heart that's working hard and beating at maximal stroke volume. That signal method of signaling it maximally is achieved when you leave two in the chamber. You pull back and you just save a few for the next day. You'll be able to back up

more tomorrow and train better if you hold on

And sometimes like the fatigue from HIIT session, it's not like your legs are sore. They're just really like dull. You climb up the stairs and you get like short of breath and you feel like your legs are made of lead.

So it's a different kind of fatigue than say you did HIIT heavy weights at the gym.

I would argue though, As a new athlete, it's good to push yourself sometimes. Till you don't have one or two left. You know, like just learning how to push yourself. Cause you will, if you're doing races or if you're planning to do races.

You're going to have to push yourself and you're going to have to need to have that confidence that you can and it's okay. And you're not going to hurt yourself. Right. Because a lot of people, they're used to doing low and slow intensity steady work and then going to the zone three, where they feel like, yeah, I'm working hard. but they've never pushed themselves till the red zone. Right. And learning to do the red zone correctly.

Yeah.

Without tanking is very useful for racing situation because in the race you're going to push yourself more than the norm.

I couldn't agree more. And if you want to learn to how to push yourself, make sure that you join, I believe it's Wednesdays with Marjaana's HIIT session that is taking off more more people there these days and that you can, yeah, you'll learn from many others on really how to do a proper HIIT session.

Yeah.

we're having a lot of fun and we're learning too. Sometimes we share our files. And that's always useful to see how different we all are.

Great.

L, another one of my athletes asked me if it was okay that if they could split up their long indoor sessions, like, you know, I think they had a three or four hour indoor session. It's cold this week in Wisconsin. it, does it matter? Is it physiologically okay in terms of adaptions to split it up into two workouts? One.

You know taking a half hour or a couple of hours off maybe a morning and a night They just have a lot of discomfort in doing long rides and we've talked about bike fit. We've talked about saddle position and getting a good fit but is there an adaptation difference between a single four-hour session and two two-hour sessions for example

there is a physiological difference in the four-hour session. You're be burning a bit more fat, but from the back to the signaling discussion, you are like, and also the practical aspect, it's not enough of a difference for it to matter. Two sessions broken as opposed to the one single.

there's really not too much of a difference. If you can do two broken as opposed to just doing only the two hours, the two by two is gonna be far superior, right? So I think it's just more than acceptable in the context

your situation. So no problem. I would just say, yeah, it's great. Don't sweat it. And also makes a lot of sense from the indoor trainers.

standpoint, like that's a lot of time on an indoor saddle and you don't get the same sort of changes in body position that you do when you're outdoor riding where you can stand and relieve some pressure for a little bit or you just, so much more easy kind of movement that's in the outdoors. You don't really even think about it. You're doing it all the time going back and forth and stuff, right? And you really notice it actually when you're prolonged indoor riding. I started to have enough after about an hour. know

Marjaana can do incredible four and five hour rides, but she's a maniac.

How did you manage those long, long rides? mean, you did four and five hour rides.

Even six and a half.

Yeah,

how did you do it? What did you do? Give us the background.

Just Finnish Sisu.

Just Finnish Sisu. Mental strength.

Hahaha

I don't seriously, I don't know. It's a mystery. It's the willpower, I guess. But I would say it also depends, like if you're training for an Ironman, you're going to have to get those long, like, sessions done. But if it's season, like why not? If that makes you sit on the indoor bike for four hours total, split them up. But if you're training for an Ironman, you're going to have to get those.

four hours, five hours, six hours sessions in.

Yeah, for sure. And because like, principle of specificity, right? You are going to be doing that during your Ironman race. So yeah, not a bad idea to try and tough it out. You know, probably didn't do six and a half hours from the get go, right? You probably did some building up to that and did some progression, right? Yeah, to do that.

Mm-mm.

Yeah, yeah, yeah.

Yeah, I think like my like longest in the beginning would be like two and a half, three hours, then four hours. And then towards the end, they were five and six hours.

Are you watching movies? What are you doing?

podcasts, motivational videos on YouTube, athletes compass.

Hahaha

Training Science Podcast,

Yeah.

sometimes chatting with Cindy.

maybe we can talk about like splitting two long runs instead of running like three hours, you could run one hour, two hour, because running is a little bit different, right?

Totally, but remember back to running, in the running context, we know that like the overall training volume of the week is kind of the more important factor than any one long run. We know that quite well and many people ask us on Athletica especially when they're either in the triathlon context or the running context, like, why don't I have a super long run if I'm gonna do a marathon, right? And the answer is because

We don't focus on that. We don't focus on the long run. We focus on trying to have a strategy to accumulate a certain training volume, the maximal training volume in the week that we can accumulate. And double run days is a well, know, tried and true method of doing that. Back to the signaling aspect, right? Think of the signals that your muscles and the various tissues are getting on, you

in that day, right? Imagine if you do a morning run where you get a very strong adaptive signal to make that whole area resilient, then you're recovering during the day, and then lo and behold, before dinner, you go out again and you get another run in, right? And you've just amplified that. You just keep signaling the body to make these aerobic adaptations, and all of the stiffening of the...

of the tendons and muscles and fascia and all the various different things. You're telling the body to, no, you are a running beast. But in the opposite strategy is to just do that one big, long, three hour run. Well, you're killed. And for whatever reason, it's just like, it's not quite as bad. It's more forgiving and absorbing to the body when it's broken and better for the long haul.

Adaptions are better. Just look at the user comments on Athletica in our forum to realize the number of people that get success with this. And you as well, Marjaana this is kind what you did as well. You said how strong you were running by the end of that Ironman, right? And you never did a crazy, what was maybe 28K was the longest? 28K was the longest run that you did.

28, yeah 28, yeah.

Hmm.

And

you know, I, you know, we've, we've seen your profile and that marathon and you, do nothing but pick up the pace, you know, in the last 5k of that marathon. So it wasn't for, it wasn't for a lack of doing a long run. It was, you know, was quite the opposite. had energy to give in the end of that race. Pretty cool.

Yeah.

Yeah. And I did do double runs and I did like morning runs short with the dog, 5k, but like every day it just adds up, but you're always feeling like you run so much better when you do frequent, like frequency running instead of like long, long runs.

Yeah. Yeah.

cool.

So that brings me to this last question that I've been getting from several of my athletes about their endurance, aerobic development, endurance rides. And they will often, you know, if they're on Zwift, if they're climbing a hill, they're concerned about getting into zones three and four during a zone two kind of ride.

Given that one goal of an endurance ride is to develop a more efficient fat metabolism. What happens when someone jumps into a zone, a higher intensity level during an endurance ride? What goes on and is that okay? does it change things? mean, what's the perspective there?

Yeah, you're splitting hairs if you're worried about too much about that. And yes, you are transitioning into more carbohydrate burning, metabolism, recruiting larger motor units, larger muscle, your bigger muscle fibers, a little bit of your fast twitch muscle fibers, your heart rate goes up. There's a little bit of slight increase in your overall, the stressors, but

If it's just for a little while, no problem. Like you got to, you got to get over that hill. So don't, don't sweat it and, and just, you know, know what you're doing, be mindful of it and just say to yourself, you know what, as soon as I get to the top of this, I'm just going to settle back in. And then, and then you do that, but it's like in the big picture of things, if it's a small little bit of zone three or four, or even zone five, like you can, you can hit those just briefly. No problem.

The trouble happens when we naturally drift and hold in zone three or four for a long time, especially zone three, because it's so, if you're not mindful and monitoring, you can talk quite easily in zone three. And the common situation is when the less fit athlete is running with their friend who's a fitter athlete.

often females joining male groups. it's, it's, is, you know, there's that drift upwards and it's, that's when trouble, trouble mounts. And it's like, you just don't even think about it. And if you're not monitoring, you'll just be completely unaware. But overall you slowly aren't doing your easy training and you're just doing, always doing hard training. you're.

central nervous system kind of rebels. It's a stress, stress, stress, stress. And then you get a little bit run down. to that question, short little bit, don't sweat it. Splitting hairs, we're carrying, you know, we're getting too anal about all the training. We just kind of, we want to be chill. We want to be relaxed out there and enjoy our training and not be overly concerned about these sorts of little things. Just using them as guides.

And that's, you know, that's been the advice that I have been giving as well and trying to convince them that, know, a small hill is a small hill, but maybe don't pick, you know, the Zwift Duets or, know, one of those, you know, massive climbs that you're going to be up, you know, so don't pick that on an endurance day. You know, pick a route that's like, you know, a little bit more simple, less hills, fewer hills.

that is all for this week. Thank you for your listener questions. We appreciate your time. Please hand us more questions. Join us next week on the Athletes Compass podcast. Ask your training questions in the comments of this podcast or on our social media or on our forum on Athletica. If you enjoyed this episode, we'd appreciate it if you would take a moment to give us a follow and a five star review. It would be awesome if you could share this episode with one

other person. more information or to schedule a consultation with Paul, Marjaana or myself, please check the links in our show notes. For Marjaana Rakai and Dr. Paul Laursen I am Paul Warloski and this has been the Athletes Compass Podcast. Thank you so much for listening.