What Running Actually Does To Your Body (No One Talks About This)

[00:00:00] 13 years ago, I did 14 weeks straight of nothing but zone two training. No tempo work, no intervals, no strength training, just easy volume. I showed up to my first triathlon convinced I cracked the code of endurance and would smoke everyone. The swim leg went poor. By the end of the bike leg, both of my quads seized up and I was having full muscle spasms, and I think I might have been probably in last place.

[00:00:24] Turns out your body never trains just one system. They’re all firing all the time. I just didn’t know how to blend them and train them the smart way. In this episode, I’m gonna be going over a whole lot of stuff, but in particular, why your body runs on two separate systems and why most runners only train one of them.

[00:00:41] Why just running without strength training is actually breaking your body down, not building it up. And a framework I call the mixing board that shows you how to train both systems without overcomplicating your week. Plus, a free training plan that has all this built in. You know what? Go and get that right now.

[00:00:55] The QR code’s right here, or the link is below in the episode description. But first, I’m Daren D. Lake, certified run coach and distance running nerd, and I’ve spent the last 30 years researching as much as possible Talking to the experts and testing it all on myself. And I tested it in that first triathlon that I did almost 12, 13 years ago because it humbled me, and the lesson made me a better coach with a goal to help 100,000 other self-coach runners avoid the same mistakes.

[00:01:21] Let me show you what I learned so you don’t make the same mistakes as me. So your body has two engines when it comes to fitness. I’m gonna get a bit into the run science weeds, but I’ll come right back out and make sure it makes a lotta sense to everyone. But these two engines, they do different jobs, but they’re bolted to the same machine.

[00:01:37] We’re gonna do a lotta machine and car analogies and metaphors here. I’ve listed them separately on the board here, but they don’t exist in a vacuum. They talk to each other. They feed each other. And when you ignore one, the other one suffers. This is true for everyone, but especially true for runners. And I’ll explain why we are special snowflakes in a hot minute.

[00:01:57] Okay, so on the left we’ve got your cardiovascular system, and for this episode I’ve lumped the lungs and pulmonary system in here too. So sorry in advance to run science Nazis watching this. They’re, they’re, they’re all the same for runners, and we’re just keeping this simple. So the cardiovascular system in this model is your heart, lungs, blood vessels, capillaries, mitochondria, all that fun stuff.

[00:02:18] The plumbing that moves oxygen into your muscles so you can run. Within this engine, there are three types of training that stress it differently from least to most intense. Now on the right- Your muscular-skeletal system, or your muscles, bones, tendons, ligaments, connective tissue, et cetera, is the chassis of the car, the physical frame that absorbs the impact every time your foot hits the ground.

[00:02:41] Based on your genetics, body type, and how long you’ve been running, your goals, and how old you are, the way you balance these two sides, so again, we’ve got the cardiovascular side and then we’ve got the muscular-skeletal side, it will look different based on your genetics, body type, how long you’ve been running, your goals, and how old you are, and probably a whole lot more variables.

[00:03:00] No one size fits all, but you need both engines firing always. Think of these as faders on a mixing board in a music studio. You slide channels up and down to get the right sound. Some faders are up, some are down, but you never fully turn anything off, and you don’t pull all faders up either. I’ll come back to that mixing board concept later in the episode because People don’t talk about this enough, and once you get this concept, you might become unstoppable.

[00:03:26] Let’s define the cardiovascular side first and go a bit deeper. So we’ve got the cardiovascular engine, and let’s focus on the aerobic base. Think of it like your engine idling on cruise control. Zone 2, roughly 60 to 80% of your max heart rate. The actual percentage differs based on many factors. So some people might be closer to 75, 80% in zone 2.

[00:03:48] That’s me. Uh, experienced and more kind of like elite runners. I’m not saying I’m elite. But experienced runners, they can have a higher max heart rate percentage and still be in zone 2. But if you’re not as experienced, it’s probably closer to 60, 65% or just genetically. Um, so that’s why I put the range there.

[00:04:04] This is the pace where you can hold a conversation. You train it with longer, easier runs, 30 minutes up to a few hours. So what does the aerobic base do? It strengthens your heart, grows more mitochondria, the tiny power plants inside your cells, the powerhouse of cells, and it builds more capillaries, so oxygen gets delivered more efficiently.

[00:04:23] Think of it like, uh, extra side roads that get to the main road if you want. And it even crosses over into the muscular skeletal side. Remember that. It crosses over. The cardiovascular aerobic side will, uh, cross over to the bone side. I did a deep dive on how to increase your aerobic base at the link above.

[00:04:41] You can click that if you’re on YouTube or below if you’re anywhere else. Zone 2 builds the foundation, but at the same point, idling on cruise control stops making you faster. So what do you think happens when you redline that engine? All right, so before we get there, you probably are like, “Well, how do I train these?”

[00:04:54] ‘Cause most likely if you’re on YouTube or anywhere else, you’re like, “Dude, I just wanna do this thing so I can get faster and run longer,” et cetera, et cetera. Don’t worry, I created a free training plan that has all these parts baked in. You get your zone 2 work, your VO2 max sessions, even tempo runs, strength days, plyometrics.

[00:05:10] It’s all in there. You also get signed up for my email course that helps you avoid the most common overuse injuries. It’s really quick. Five minutes a day, six days in a row. Go get it at the QR code here or the link below in the show notes or the description wherever you’re listening or watching. And in a bit, I’ll show you exactly what a sample training week looks like from that plan.

[00:05:31] So what do you think happens when you redline that engine? Enter the VO2 max area of the cardiovascular engine. This is, again, redlining your engine. This is actually good. We wanna do this just for precise short periods of time. The maximum amount of oxygen your body can use during hard exercise. This is VO2 max.

[00:05:47] You train it with high intensity intervals ranging from 30 seconds to five minutes with a decent rest in between, uh, usually half if not more than what you did, and it’s at a pace that might make you question- A lot of life choices by the last rep and you go, “Why, why am I doing this to myself?” But you’re still ironically using oxygen for mostly fuel when you do these hard reps in VO2 max.

[00:06:07] So think of zone two, the aerobic system, like daily driving that keeps the engine smooth and efficient. It’s great for reliability and fuel economy, but it won’t reinforce the chassis or upgrade the suspension. VO2 max work is when you stress test the whole machine, AKA your heart, near its limit so the top end actually gets stronger.

[00:06:25] If you’ve never done VO2 max work before, you can start with one minute on, one minute off That’s kinda more a threshold workout, but it still works your VO2 max system. They all blend together. Then you can do two minutes on, two minutes off, three minutes on, three minutes off, four minutes on, three minutes off, five minutes on.

[00:06:40] You can, like, do that or you could do, uh, 12 by 400s or six by 400s if you wanna start out. You could do 30 seconds on, 20 seconds off. There’s a lot of variations. I did a deep dive. There’s a lot of deep dives in here, ’cause this episode will blow out to be very long. You can go check that out on all the different VO2 max workouts up top, or below if you’re somewhere else watching or listening.

[00:06:58] So zone 2 is cruise control. VO2 max is redlining it. Now let’s talk about what happens when you hit the running version of the nitrous oxide turbo boost button. So now we’re in the anaerobic part of the cardiovascular engine, cardiovascular fitness. So again, this is the nitrous boost. These are short, all-out efforts lasting anywhere from 20, 30 seconds up to about two minutes.

[00:07:19] So it’s hill sprints, 2 to 400 meter repeats, depending on how fast you run them. Again, basically up to two minutes. Your body can’t deliver oxygen fast enough, so it burns stored fuel directly. Fast energy, but the tank is tiny, minuscule. Now, here’s what blew my mind when I first learned this. You know how you’re not tired after you sprint or lift heavy weights or do plyometrics, jumping-type exercises, but right after you’re gasping for air between sprint reps, even though the effort was supposedly without oxygen?

[00:07:49] ‘Cause anaerobic is without oxygen, aerobic is with oxygen. Greek. That’s because your aerobic engine kicks in during the rest period to replenish the fuel that you just burned. Your cruise control system is refueling the nitrous system between intervals. Sprint work has a direct cardiovascular training effect.

[00:08:06] It’s pretty dope, right? So those are your three cardiovascular training types, and even within this one engine, they’re all feeding each other. But we haven’t even talked about the other engine yet, and for runners, this is where it gets uncomfortable. All right, so we got the cardiovascular engine covered.

[00:08:21] Now let’s talk about the other engine, the musculoskeletal engine. This is the one that runners ignore, and this is the scientific medical name, the musculoskeletal system of the engine. But you probably know it more as your muscles, bones, tendons, ligaments, connective tissue, AKA the chassis and the frame that carries AKA you, AKA your body.

[00:08:40] And I need to say something a lot of runners they might not wanna hear, they don’t even know about. So running is catabolic. Catabolic means it breaks muscle tissue down. Every foot strike is pretty much impact stress. Repetitive light load on the same joints, even easy runs, same tendons, same bones, run after run.

[00:08:56] When you do most workouts, especially hard ones, your body ramps up stress hormones like cortisol. So workouts as in run workouts, tempo runs, VO2 max, et cetera. You basically are in zone 3, zone 4, and going really hard, and even racing. Muscle fibers get micro damage, and unless you recover and add a strengthening stimulus like progressive lifting, heavy strength work in the gym, your body often just repairs back to baseline instead of getting more resilient and stronger.

[00:09:21] You’re not- Progressing things. I hear runners saying, you know what? I used to say this too, “I run three hours a week, I’m fit. I don’t need to go to the gym.” Your heart, yeah, that’s probably getting quite fit, but the chassis holding it all together, it might be slowly rusting out. Running is the force that wears the car down.

[00:09:38] Strength work and recovery are the mechanic that builds it up. Without that, you’re driving without ever servicing the machine. And this is the longevity piece that gives this running health and fitness thing a much higher meaning. The musculoskeletal engine isn’t just about race day speed, it’s bone density, tendon resilience, the difference between running your whole life and being the person who used to run but my knees gave out when I was 50 years old.

[00:10:00] Your knees didn’t fail because of running, they failed because you never reinforced the frame around them. So within this musculoskeletal engine, here are the main upgrades you can train. We got muscular endurance. This is how long the engine can hold highway speed before it overheats. This keeps your legs turning over late in a race.

[00:10:17] Hypotrophy spelled hypertrophy. You wanna think of this as like thicker body panels. This is what happens when someone gets jacked and gains more muscle. More muscle means more force and a bigger reserve usually. But more muscle does not necessarily mean being very strong though. It gets a bit nuanced here.

[00:10:34] So we got strength. That’s your reinforced frame. It protects your joints and prevents overuse injuries. Strength doesn’t need muscle to be effective, so you can be strong without actually being super like bulky jacked. Look at Anatole. Go look him up. Uh, he’s awesome on YouTube and TikTok and everywhere.

[00:10:51] A-N-A-T-O-L-E, I think. Dude is hilarious. Go check him out. But yeah, he looks very, very skinny, but he’s super strong. And then you got speed and power. This is the turbo boost when you floor it. Think running up a steep hill in the middle of a race or when you load up to do a plyometric jump or even fast form drills.

[00:11:07] This is your finishing kick. And then you got last, mobility under kind of this whole musculoskeletal system. This would be like a smooth suspension over rough roads. You get full range of motion without fighting yourself. Mobility is a close cousin to flexibility, but a good way of remembering this is that the difference between mobility and flexibility is mobility is how strong you are and how powerful you are when you’re at the end of your range of motion.

[00:11:30] So when you stretch something, how, like how much can you actually move it at the end of the stretch? That’s mobility. Uh, it’s like when you do strides and it’s how well your hips rotate To get your knee up and then your heels actually kick your butt, and you c- make that circle. You see the pro runners and sprinters, even pro distance runners, marathoners, they make that really nice pretty circle because they have really good hip mobility.

[00:11:53] They have strong hip mobility, have a lot of it, their hips can actually move. That is mobility. It’s done through strengthening of their hips. It’s not actually done from stretching. I did a whole deep dive on all those things, uh, at the episode up here or below if you wanna go check that out and see how I lifted like, a, a pro runner for about three or four months.

[00:12:12] And something that I always remind runners, most research shows measurable tendon adaptations take at least eight weeks, sometimes longer, while your aerobic system improves in just a few weeks. So that mismatch creates a window where you feel fitter than your tissues are ready for. This is like you going, “Oh, my lungs.”

[00:12:28] This is a big thing. People go, “Oh, don’t you get tired after running a marathon?” It’s like, no, once you get really fit, it’s not your lungs and your blood and your cardiovascular system that hold you back, it’s actually your body that holds you back from finishing a marathon or getting to the start line healthy.

[00:12:42] And most runners live in that window, that mismatch of having a really strong cardiovascular system and a weak musculoskeletal system, and that’s when the injuries happen. That’s exactly what happened again in my triathlon. Uh, luckily I didn’t get injured, but my cardiovascular engine was writing checks that my body could not cash.

[00:12:59] And if you’re out there doing zero strength work right now, start with two sets of 10 body weight squats before run, after run, probably after run, and then two sets of 10 calf raises. You could do two legs at first, and two weeks later do each leg. Do that three times a week, five minutes. Right at the end of your run, you’re already sweaty, you already have clothes on, you’re already ready to go, you’re warmed up.

[00:13:20] That’s enough to start reinforcing the chassis. Once you get past that, though, you’ll need to actually lift heavy weights, either dumbbells or kettlebells at home, or go to a gym and actually lift heavy. I did a whole deep dive on that, the ten most effective and time-efficient strength workouts for runners.

[00:13:37] Go get that up top on YouTube or below, anywhere else you’re listening or watching. And now you know the two engines both matter a lot, but how are they connected? Welcome to the two system crossover. This is where the two engines don’t just sit side by side, they feed each other. Zone two builds a stronger heart, which pumps more blood, which raises your VO2 max ceiling.

[00:13:58] VO2 max training pushes the top end, which builds your buffer before you cross over into anaerobic territory. And anaerobic work forces your aerobic system to replenish the fuel between reps. So ironically, sprint training actually improves your aerobic pace. See that crossover? Gotta love that. You could also look at it as a circle.

[00:14:14] All right. Quick run science nerd break. A review of 102 studies found that even a ten-second all-out sprint, AKA 100-meter dash for any pro, uh, 100-meter runner, Usain Bolt, it’s 9% aerobic. Your aerobic engine is actually online from the first second. It’s not that much, but it’s online 60 seconds all out or as fast as you possibly can hang on for, that’s 42% aerobic.

[00:14:37] It’s using the aerobic system. And two minutes max effort, if you can even do two minutes, two minutes is crazy long to be sprinting, 62% of the energy is aerobic depending on the person. And a bunch of other research has shown that the 5K is anywhere from 75 to 90% aerobic. It’s less aerobic for faster runners and more aerobic for slower runners.

[00:14:55] So that 5K race that you call a sprint that you do in between your marathons, you know, like every four to eight weeks, “Oh, I’ll just do a 5K. I’ll do a sprint 5K,” it’s actually mostly aerobic. Your base training isn’t just for marathons, it’s feeding everything, and it goes the other direction too. So strength training, plyometrics, form drills, and strides all improve your running economy.

[00:15:16] This means less fuel burned at the same speed, so this is running efficiency or fuel economy. Uh, it’s how aerodynamic you are, how good your tires are, and how well your suspension is, and all those small little 1% variables, they stack up so you run at the same heart rate or the same power or effort and you go faster.

[00:15:32] Power work and hill sprints develop your anaerobic system too, which feeds VO2 max, which feeds aerobic base. It’s a loop. They’re all connected. Cycles. And speaking of connections, if you want to help out another self-coach runner get 1% better, dope, just watch this until the end. That’s it. You know, super easy.

[00:15:47] You know, if you don’t want to hear me talking, put this on 2X speed and then mute me while you check your Strava if you can’t wait. This signals to the algorithm that this content is for runners like you that want to self-coach themselves and figure this all out. And if you’re feeling spicy, you can like, subscribe, and share out this episode, uh, text, email, whatever.

[00:16:04] Or you know what? Easiest thing, probably just comment below whether you’ve been training both engines or just one. I’m legit curious because my gut says a lot of runners don’t lift heavy weights, but I do see and hear otherwise, which is always interesting. I love being proven wrong. So we got the two engines.

[00:16:19] They’re all connected. But how do you actually train this without overcomplicating your week? We have now entered the mixing board. This is my favorite part. So back in a previous life, I was a musician, DJ, performer. I was on the mic singing, dancing, rapping, and I used a mixing board in a lot of my sessions.

[00:16:35] Yeah, the thing with the faders that looks intimidating to people, it’s actually not once you learn one channel because you apply it to the rest. And on a mixing board, you’ve got faders for every channel. Let’s say we’re in the studio again. We got vocals, guitar, bass, drums, synthesizers, et cetera. You slide them up and down to create the right mix for your song.

[00:16:52] Your training works the same way. You got a fader for zone two, a fader for VO2 max, a fader for anaerobic strength, power, mobility. Throughout the year, you’re adjusting the levels. And because training is seasonal, just like the weather changes, just like work has busy seasons and slow seasons, or school, your body needs different things at different times.

[00:17:10] The runner who does the exact same thing every week for 12 months is like a keyboard player playing the same note and holding it for minutes, like technically making sound, but it’s not music because as the late great Prince said, “The silence between the notes is what makes the music sound good.” Here is periodized training theory in a quick YouTube video style nutshell.

[00:17:28] So you got base phase, zone two cranked high. Strength is moderate to high, building resilience in those slow adapting tendons. You got threshold/tempo zone three-ish and VO2 max zone four-ish faders. They’re low, but they’re not off, and you’re laying the groundwork for both engines. Most runners skip this because it doesn’t feel like real training because it’s slow and it’s too easy.

[00:17:48] Surely easy can’t make you go faster It does, and it’s the most important phase. Without a base, you can’t build a super fast race car. This can be anywhere from 8 to 16 weeks or longer, depending on your experience and what your race is, and you can have multiple base phases. You know you’re ready to move on when your easy pace at the same heart rate has stopped improving for two to three weeks.

[00:18:09] Again, I like to give a minimum 8, 10 weeks, sometimes 12. All right. The next is the build phase for your upcoming race. We start bringing in harder sessions gradually, though. Think again, threshold tempo, zone three, and VO2 max, zone four. Faders, they gradually come up as the weeks progress. Strength shifts towards power and running specific work.

[00:18:28] It will start flattening out a bit here, and that’s fine, but we wanna maintain the load, which is the heaviness and the volume. Zone two dials back a touch but stays the biggest chunk still in this build phase. Your body is now strong enough from base to absorb the stress. This is connecting from your base phase to your race phase, and you can think of it like tuning the engine for months, and now you’re taking it to the track to see what it can do.

[00:18:50] This is usually 6 to 12 weeks out. And again, you can have multiple build phases depending on how many A races you have each year. I would cap the A races at three and preferably two. Please, please don’t do more than two marathons in a year. I don’t care if you’re pro. Please. You don’t, you don’t need to do that.

[00:19:05] More than two marathons, it’s cra- it’s craziness. Tell me if you do more than two marathons in a year. Please, I wanna know who you are. All right. And then the last period is the race prep phase. VO2 max is now in maintenance mode. We are doing one VO2 max session every 7 to 14 days while doing one to two tempo or threshold runs per week because threshold, I found, is usually what is needed to run fast with anything that’s longer than 5K, uh, which is most amateur distance runners.

[00:19:31] They’re doing 10Ks, half marathons, marathons. Anaerobic gets a bump for shorter races though, so it’s kind of an asterisk. So 5K people down the mile, if you do that, you wanna do a bit more anaerobic work than threshold work, but that just depends on a lot of factors. And then the strength training will drop down in this period to more of maintenance mode, so about one to two days a week.

[00:19:51] Uh, definitely one day a week in the last few weeks leading up to your A race. And you also wanna drop down the overall volume so you’re keeping the weights heavy. Instead of doing Four heavy sets of squat with five reps each. I do two heavy sets of squats with five reps each. So 10 overall reps instead of 20.

[00:20:08] That’s kind of like an example and you can apply that to all the other exercises you do in the gym or at home. And it’s just enough to hold what you’ve built because you’re pushing your body to the limit with race pace efforts. So you’re actually getting a lot of the strength training benefits from running so hard.

[00:20:23] This period, the race period, uh, can be six to 12 weeks depending, again, on how long your event is, your A race is. So an experienced marathoner, maybe they have three, four years of marathoning under their belt or more and they’ve done three, five, 10 marathons, et cetera, I would have them do 12 weeks of marathon-specific building.

[00:20:42] And then if it’s a new 5K runner though, because a 5K’s shorter and they’re new, I would only have them do about six weeks of 5K-specific training in this race period. So you see how it just changes for everyone. All right, and then the last period is the off-season. I love the off-season. This is where runners mess it up though.

[00:20:57] They either stop completely or keep doing the same thing as the build and race phase ’cause, you know, we, we love consistency. We’re all type A personalities. For me, in the off-season, I love to bump strength training way up, uh, as well as cross-training. So running volume will drop, mobility rises ’cause we’re working on the chassis and we can handle that because we’re doing way less running.

[00:21:19] So if we’re on the race car track, this is the long pit stop. You’re not losing the race. You’re making sure the car doesn’t fall apart in the next one. You’re putting back everything that the build and race phase took out and again, you’re never all in doing one thing. So that training plan that you can download, here’s like a quick sample of it.

[00:21:35] In practice it’s pretty simple. Most runners I coach train four days a week, uh, and I’ll talk about three days in a second. One strength. They’ll do two easy runs, one hard session day, and one long run that’s usually easy-ish, and then, uh, one to two strength days, and then plyometrics thrown in there, strides are thrown in there.

[00:21:52] And if you only got three days, I like to do one easy run, 30, 40 minutes, one hard interval session, and then one long run that’s easy. That’s your bare minimum to touch both engines. We got one strength training day minimum. Try to get two in there, especially early in the season. We’ll be doing our plyometrics, microdosing those, and our strides that also bring strength up, and our hill sprints.

[00:22:11] That’s the bare minimum to touch both engines and make sure that everything stays nice and tight. And you know what? If you haven’t already, go and get that free base training plan because it explains all this and has it all laid out, 30 days, and you can figure it out all yourself because right after you get that plan, you’ll get six emails in your inbox one day after another, five minutes or less to read, and they actually help you.

[00:22:30] It’s a course that actually helps you understand how to make your own training plan and remix what I did. So you can transform yourself into the self-coach runner that I know you wanna be, that can run faster, farther, easier, less effort, and hopefully injury-free. Get it at the QR code here or the link below wherever you’re listening.

[00:22:47] Uh, if it’s not YouTube or watching, get it below. And now that you know about both engines, make sure the musculoskeletal side isn’t leaking energy with every step. So go watch my deep dive on cadence and stride length because it ties directly into everything we just covered, and you’re able to advance all of this information.

[00:23:04] Click the video below on YouTube if you’re watching, or the link is in the episode description wherever you’re listening or watching somewhere else like Spotify, et cetera. Peace.