Pete Wright:
So I pretty much try to do anything that Srdjan tells me to do in the gym. He points at things that are heavy, and then I do my best to lift them up. And I do split squats that I absolutely hate in a deeply personal way. And then he tells me to go to bed. So I turn the lights out. I try to go to bed. And then after I try to go to bed, I pick up my phone, and last night I watched a 45-minute video of some guy making real Wolverine claws in his home metalsmithing shop. That’s what I did last night instead of sleep. It turns out that that overnight time is also my muscles’ overnight time, and I’ve been spending it on real-life Wolverine claws videos.

Not great. Before I left on vacation this summer, I asked Srdjan for one thing to focus on, and I figured he would tell me a lift that I should do. Like, go find a tree and lift it up a bunch of times. And instead he gave me sleep, and today we’re gonna find out why. We’ve talked about recovery a bunch. We did it specifically in episode five a long time ago, and sleep came up, but we kind of barely scratched it. This time we’re gonna go a little bit deeper. We’re gonna get into what your muscles are up to while you’re unconscious. We’re gonna talk about what a few short nights actually cost you, and we’ll try to get a little bit practical for people who just don’t sleep well, which is a lot of you, and also me.

Quick note before we start: this is not medical advice. If you think you’ve got a real sleep problem, there are doctors for that, and you should go talk to them. I’m Pete Wright, he’s Srdjan Injac, and this is Build for Health.

Okay, man, hi. Welcome back. First of all, welcome back from a well-deserved vacation that you just had. Globetrotting, traveling the globe, and by globe I mean the sum of the continental United States.

Srdjan Injac:
Oh, yes. It felt amazing. I got plenty of sleep.

Pete Wright:
There you go. And then you came back and blew it all to hell.

Srdjan Injac:
Yes.

Pete Wright:
How’d you sleep last night? Terribly.

Srdjan Injac:
Can we not talk about that one?

Pete Wright:
Please allow our lives to serve as a warning for others. That’s what I like to say. So let’s kick this off and talk about sleep and why it’s kind of low-key important. Why does sleep get its own episode? We did a whole episode on recovery. Why do we need to spend any more time talking about this stuff?

Srdjan Injac:
It’s really important. People don’t really think about how much sleep plays a huge role in your recovery. I mean, it can mess up the whole thing. It’s just because it creates a perfect environment for that recovery. So if you don’t create that perfect environment, your recovery is not gonna be as good as it probably could be. And it messes up all kinds of things, and we’ll talk about it all: hormones and the levels and everything. I mean, it affects your whole day, the whole training, the whole muscle growth, weight loss, and there were some studies that they did on that and how important the sleep is.

Pete Wright:
Well, and we should say, you’re saying it messes up your recovery, and I just want to make sure we say loud and often that recovery is when your muscles are building and getting stronger, not in the gym, right?

Srdjan Injac:
Yes. So what you do at the gym, and I tell people all the time, and you see people flexing at the gym or they’re working out, you’re still the same size. You didn’t grow any bigger. You’re still gonna walk out the same size that you came in. It’s just a pump. It’s just blood flow. Because all you do is you’re damaging the muscle. You’re breaking down the muscle, the fibers.

Pete Wright:
Listen.

Srdjan Injac:
That’s what you do at the gym. And I try to do it as much as I can from every angle and tear that muscle as much as I can, so that way when it recovers, it can actually grow bigger and stronger. That’s why we always say put some more pressure on that muscle, give it a reason to change. The body’s not gonna change unless you give it a reason to change, to adapt to that environment. But that adaptation, that’s when all that happens: it’s when you go to sleep.

Pete Wright:
Okay.

Srdjan Injac:
That’s why it’s important to get that.

Pete Wright:
All right. I want you to walk me through the proverbial night shift. What is happening? So let’s say I come in, I lift at four or five o’clock in the evening. I come home, I eat dinner, get all my protein, probably eat a whole chicken, whatever.

Srdjan Injac:
Okay, whatever.

Pete Wright:
And then I go to bed around 10:30. What’s gonna happen to my body between 10:30 and 6?

Srdjan Injac:
So we just touched on the subject of muscle growth during sleep, so we’ll break it down. What people mean when they say that you need to recover and grow while you sleep: you don’t go to bed with a damaged muscle and wake up with a brand-new muscle overnight. But sleep creates that important, like I said, environment for the recovery and adaptation process that resistance training started. So when you train, mechanical tension activates signaling pathways inside the muscle that increase muscle protein synthesis. Then the protein you eat provides the amino acids that your body can use to repair and remodel. Now, that process continues for many hours after the workout, including while you’re asleep.

So one of the most important parts of the night for physical recovery is deep sleep, also called slow-wave sleep. During deep sleep, your nervous system shifts toward a more restorative state. Heart rate and blood pressure decrease, and you get a major natural pulse of growth hormone. Growth hormone isn’t simply a muscle-building hormone like people sometimes describe it. It has important roles in tissue repair, connective tissue, bone, and metabolism. So deep sleep is part of this larger recovery environment that your body creates after you train.

Testosterone also follows a sleep-related rhythm. Levels generally increase during sleep and are typically higher in the morning. So when you wake up, people know they have a little bit more energy; testosterone is really high in the morning. When sleep is repeatedly restricted, particularly when the restriction is significant, testosterone can be negatively affected. So now think about someone trying to maximize muscle growth but consistently sleeping four or five hours a night. They’re doing all the work, eating their protein, but they’re compromising another part of the recovery environment they’re trying to create.

Sleep also gives your nervous system a chance to recover. Remember, strength isn’t purely muscular, and we talked about that when we talked about the brain. Every time you squat, bench, deadlift, or perform any movement, your brain and nervous system are coordinating that movement. So sleep supports motor learning, memory, and neurological recovery. That’s why good sleep can affect not only how well your muscles recover, but how well you perform those movements the next time you go to the gym and train.

Pete Wright:
Sure. So okay, you just threw a lot of stuff that’s happening at night, and all it makes me really think is I should definitely be working out at night, so that my muscles are all activated before they go to sleep and rebuild immediately. So let’s talk about challenging that schedule assumption, and also about how I should manage my protein intake in and around my sleep schedule. Should I just be dosing on some protein energy drinks, or eat my chicken right before bed at like 10?

Srdjan Injac:
No, you don’t have to. You don’t have to as long as you get your daily protein intake by the end of the night. For example, everyone’s a little bit different. I really can’t go to sleep if my stomach is growling and I’m hungry. My metabolism is really fast, so it eats up everything. So I have to eat at least an hour and a half before I go to bed. Otherwise, if it’s two, three hours before I go to bed, I’m hungry. I can’t fall asleep.

Pete Wright:
Mm-hmm.

Srdjan Injac:
It just keeps me up. But some people have a hard time falling asleep if they’re full, if they just ate and all that stuff, and then it’s like, okay, when you eat, move around a little bit, go for a walk before you go home and then relax and go to bed. So the time when you take that protein, it’s not really that important. After the workout, of course, you wanna get that protein in. And with every meal and snack, you try to get at least 25 to 30 grams of protein just to activate that protein synthesis.

Pete Wright:
Sure. Okay, but then address the timing-of-the-workout issue, because I know there are people who believe very strongly that working out in the evening makes their sleep better.

Srdjan Injac:
[crosstalk]

Pete Wright:
Is that just a personal preference, or is there anything behind it?

Srdjan Injac:
That’s just a personal preference. Some people, like me, can’t really work out in the evening. I’m tired. My body is starting to go to sleep and I’m at that relaxing stage. I don’t have the energy. I have to do it before three or four o’clock in the afternoon. After that, if I miss that window, I’m probably not gonna do my workout. I might do cardio, fifteen, twenty minutes of cardio. I can do that.

Pete Wright:
I like how you say that so derisively.

Srdjan Injac:
But—

Pete Wright:
“I might do cardio,” like a chump.

Srdjan Injac:
I might do it. I might think about that as well. Or call it a rest day.

Pete Wright:
You’re so catty.

Srdjan Injac:
Focus on my sleep.

Pete Wright:
Okay.

Srdjan Injac:
But yeah, it doesn’t matter. Everyone’s schedule is a little bit different. They work out around their work schedule and whenever they can.

Pete Wright:
Yeah.

Srdjan Injac:
I mean, I have people come in at 5 a.m. to work out; some of them come in at 8 p.m.

Pete Wright:
Yeah, okay.

Srdjan Injac:
[crosstalk]

Pete Wright:
Okay, so sleep debt. I have heard conflicting things about sleep debt, because the implication of sleep debt is that if you don’t sleep well one night, you can make it up another night. And my understanding is that’s not accurate. You never actually get to pay back the debt on sleep that you’ve skipped.

Srdjan Injac:
Yeah, sleep debt is basically the accumulated difference between the sleep your body needs and the sleep you’re actually getting. So if your body needs somewhere around eight hours and you’re repeatedly sleeping five or six, you’re continually operating with insufficient sleep. And I want to be careful with the word catabolism, because people hear “catabolic” and they think their muscles are just suddenly gonna disappear overnight.

Pete Wright:
Say the word again? Catabolism?

Srdjan Injac:
Yeah, because of catabolic states.

Pete Wright:
I’ve never heard that. I’ve never even heard of that word. You’re just making stuff up now. God.

Srdjan Injac:
No, catabolic states. Your body is always building and breaking down proteins. So what matters for maintaining and building muscle is the balance between those processes over time.

So when you’re trying to build muscle, you want to create an environment that favors muscle protein synthesis and recovery. Significant sleep restriction can push things in the wrong direction. There’s research that has shown that sleep deprivation can reduce muscle protein synthesis. It’s crazy. And inadequate sleep can also affect hormones and metabolic processes involved in recovery. So combine that with hard training, a calorie deficit, a high level of stress, and you’re asking your body to recover while continuously taking away one of its most important recovery resources: sleep.

This becomes particularly important when you’re dieting, when calories are already restricted and preserving muscle becomes a priority. You’re giving your body less energy while still asking it to train hard and recover. So add chronic sleep deprivation on top of that, and you’re potentially creating an even worse environment for maintaining lean tissue, the muscle mass that you’re supposed to maintain while you’re losing weight. So one bad night is not gonna make you lose muscle, and even several bad nights is fine. But if there’s a certain pattern, yes.

Pete Wright:
Chronic bad nights over and over becomes problematic.

Srdjan Injac:
Yes.

Pete Wright:
Do you have a sense of whether training can actually be sort of protective of your muscle?

Srdjan Injac:
[crosstalk]

Pete Wright:
Say you have a chronic sleep problem. If I train more, am I doing anything to protect myself a little bit? Or is it just a wash? I know I’m not building much.

Srdjan Injac:
Yeah, you’re not building much.

Pete Wright:
Yeah.

Srdjan Injac:
You’re probably just trying to maintain whatever you have.

Pete Wright:
Yeah, okay.

Srdjan Injac:
But—

Pete Wright:
Mostly it just feels like I’m using training to hide debt that I need to get a handle on.

Srdjan Injac:
Yeah, exactly. For example, I know sometimes I’m guilty of that. I don’t get much sleep, like last night. I do take a lot of naps. I’m actually a big fan of naps when they’re used correctly.

Pete Wright:
You’re a European. You come here already deep into nap culture. I know. I get it.

Srdjan Injac:
Yeah. I’m actually a big fan of naps when they’re used correctly. So if you had a terrible night of sleep, or you’re exhausted from training and everything, a nap can help improve alertness and mood and performance.

Pete Wright:
Yeah.

Srdjan Injac:
A short nap, maybe around twenty to thirty minutes, can give you that boost without allowing you to go too deep into sleep and waking up feeling like you don’t know what planet you’re on. Longer naps can have benefits too, because you have more opportunity to enter deeper stages of sleep. But then there’s a trade-off. If your nap is too long, you might wake up, like I said, groggy, and have trouble falling asleep at night.

Pete Wright:
Yeah, yeah.

Srdjan Injac:
So naps are not really a replacement for consistently not getting enough sleep at night. Another thing I tell people: don’t become obsessed with getting the perfect eight hours every time. It’s not realistic. Things happen. One night isn’t gonna destroy the progress; just try to get as much sleep as you can every night. What matters much more is the pattern.

Pete Wright:
Yeah, yeah.

Srdjan Injac:
If you keep getting those four or five hours and then return to a normal sleep schedule, going back and forth is just gonna throw everything off.

Pete Wright:
What does a really rough sleep schedule do to body composition?

Srdjan Injac:
It has a huge effect. I actually had a client asking me if it affects their fat loss.

Pete Wright:
Yeah.

Srdjan Injac:
So—

Pete Wright:
Yeah, if I’m dieting and I’m not sleeping well, is there even a point?

Srdjan Injac:
People sometimes don’t realize how much sleep can affect what they’re trying to accomplish. You can have your calories figured out. You can meal prep, you can train five days a week and get your cardio in, but if you’re constantly exhausted, sticking to that plan can become harder. So let’s talk about hunger. After a night of poor sleep, I don’t know if people ever noticed, they’ll wake up hungrier the next day. And you’re usually not craving chicken and vegetables and salads. You want something sweet and salty and fatty, high in calories.

Pete Wright:
Yeah, yeah.

Srdjan Injac:
So there’s actually a physiological reason why that can happen. Sleep affects several systems involved in hunger, appetite, and food reward. There are two hormones that are affected. One hormone helps stimulate hunger, and another one helps communicate information about your body’s energy stores and plays a role in regulating appetite. Some studies have found that sleep restriction can increase the hormone that helps stimulate hunger and decrease the other one. So you actually wake up hungrier.

So you’re throwing off all your hormones. And that’s why people sometimes have a hard time sticking to their routine. The hunger and food cravings can increase, and people tend to consume more calories.

Pete Wright:
Yeah.

Srdjan Injac:
And it’s important, because sleep deprivation doesn’t magically stop you from losing fat. You’re still gonna lose fat if you’re in that calorie deficit. It’s not like you’re not gonna be losing fat. It just becomes a lot harder.

Pete Wright:
What’s so interesting, I found a study from 2017, which said—

Srdjan Injac:
Mm-hmm.

Pete Wright:
Short sleep adds 385 calories a day with no change in calories burned. So when you think about what you’re already doing while lifting and dealing with a calorie deficit, you have to offset that by 385. That’s like an extra meal.

Srdjan Injac:
Yeah.

Pete Wright:
Right? Just for getting bad sleep.

Srdjan Injac:
That’s crazy.

Pete Wright:
You could do nothing, meaning you could be asleep, and not have to worry about almost 400 calories of caloric restriction or caloric deficit if you’re dieting. I mean, come on.

Srdjan Injac:
Yeah. So that’s why it’s so important. But then there is also insulin sensitivity.

Pete Wright:
Yeah.

Srdjan Injac:
Insulin helps your body manage glucose and move it from your bloodstream into your cells, where it can be used for energy or stored.

Pete Wright:
Yeah.

Srdjan Injac:
Even relatively short periods of inadequate sleep have been shown to reduce insulin sensitivity. And over time, consistently poor sleep is associated with a greater risk of insulin resistance, obesity, and type 2 diabetes. So we’re not just talking about whether you can see your abs. We’re talking about your metabolic health.

Pete Wright:
Yeah. I want to talk about giving folks some architecture around sleep. What do people who don’t sleep well actually do?

Srdjan Injac:
[crosstalk]

Pete Wright:
Actually, let me start by asking you: do you track your sleep? Do you have any sleep devices going on?

Srdjan Injac:
I do have my watch.

Pete Wright:
Or is it too embarrassing?

Srdjan Injac:
No, my watch. And sometimes I’m looking at it and I’m like, “That’s not right. The watch is lying. There’s no way.” I mean, they’re not completely accurate. Just because your watch said you spent only thirty minutes in deep sleep—

Pete Wright:
Yeah.

Srdjan Injac:
—what happened last night? I don’t think that’s true.

Pete Wright:
Yeah.

Srdjan Injac:
But I look at how often I’ve woken up that night.

Pete Wright:
Yes.

Srdjan Injac:
How many times I woke myself up, either snoring or getting up to use the restroom and then couldn’t fall asleep and then woke up again and all that stuff. Or if I got one really solid night where I didn’t wake up, or maybe just woke up once.

Pete Wright:
Yeah.

Srdjan Injac:
That’s kind of how I measure mine. You have all these rings and watches and all that stuff, and they’re not always a hundred percent accurate. They just give you an idea.

Pete Wright:
I’ve been sleeping with the watch on, and last night I had a score—

Srdjan Injac:
[crosstalk]

Pete Wright:
—of 83.

Srdjan Injac:
Uh-huh.

Pete Wright:
That seems like a good score. It actually tells me that’s a good score. And I was up eleven minutes overnight. Just a couple, like you said: get up, go to the bathroom, whatever. That’s pretty good for me.

Srdjan Injac:
That’s pretty good.

Pete Wright:
I’m coming off of years of terrible sleep. Terrible, terrible sleep.

And when I look at my data, it lines up with when I started training. My best night’s sleep is right after training.

Srdjan Injac:
Uh-huh.

Pete Wright:
And as long as I keep training every other day, I tend to sleep pretty well now. I joke about the Wolverine thing. I legit watched that, but I still had a good night’s sleep last night, and it lines up. Even if it’s not what I would get if I went in for a sleep study and they put a bunch of sensors and whatnot on me to actually measure my sleep, what I do get is consistency. And I can see, relative to last night, how was tonight?

Srdjan Injac:
[crosstalk]

Pete Wright:
Or what can I expect tonight? And see trends over time. That has been useful to me, to remind me when my behavior is getting in the way of sleep.

Srdjan Injac:
Yeah. I love watching it to see deep sleep, REM sleep, light sleep, because there are different stages.

Pete Wright:
Mm-hmm. Yes.

Srdjan Injac:
You have to understand the different stages. In every stage, something happens. Light sleep helps your body transition out of the alert, stressed state into deeper recovery. So if your sleep is constantly interrupted and you keep getting pulled back into light sleep, you may wake up feeling like you’ve slept for seven hours, but you never really feel refreshed.

Pete Wright:
Yes.

Srdjan Injac:
Deep sleep is especially important for physical restoration. This is when you get a major release of growth hormone and your body is supporting tissue repair and recovery.

Then there is REM sleep, which is heavily involved in learning, memory, and emotional processing. That’s important for training because lifting isn’t just, like we said, muscular. It’s neurological. Your brain is constantly learning these techniques and movement patterns. So poor sleep can affect things like focus, reaction time, and coordination. So I like to see how much time I spent in each of these stages. Once you understand the stages, you understand how much of what kind of recovery you got, because every stage plays a different role in your recovery.

Pete Wright:
Okay, so give me your short list. Beyond my nerding out about wanting to collect more sleep data, what’s your short list for the things that actually help you sleep if you’ve been struggling?

Srdjan Injac:
Well, I limit time on the phone. Once I get in the room, for an hour, and I’m sure it’s a little bit more than an hour, maybe an hour and a half, two hours, I’m not on the phone at all. I put the phone away, because the light from the phone just keeps me awake. I dim the lights, turn the lights down in my room. I also avoid caffeine. If I’m gonna have an energy drink or pre-workout, I make sure I do that earlier in the day, so that way it doesn’t affect my sleep either.

I also take zinc and magnesium. Magnesium apparently helps really well. So I do those little things, and they help me. Sometimes I get in and take a shower, and—

Pete Wright:
Kind of relax you.

Srdjan Injac:
Just different things that get me into that relaxation mood, so my body’s ready to go to sleep.

Pete Wright:
Yeah. A thing I never really appreciated when I was younger that I do now is just the degree to which alcohol absolutely wrecks my night, even a little bit.

Srdjan Injac:
Oh yeah.

Pete Wright:
If I drink in the evening, my sleep is just destroyed anymore. And so as a result, I’ve just had to stop.

Srdjan Injac:
[crosstalk]

Pete Wright:
I just can’t enjoy a glass of wine with food anymore. At lunch? Oh, I can. I’m a real power player at lunch. But at night, I can’t anymore. That gets me.

Srdjan Injac:
Yeah.

Pete Wright:
And the other thing, and check me on this if it’s a fable, but it does work for me: getting up at the same time every day. Not having special days where I try to sleep late—

Srdjan Injac:
[crosstalk]

Pete Wright:
—as some sort of a splurge. Actually waking up every day at the same time really helps me feel ready to go to sleep the next night. My body and brain have a routine that they get into.

Srdjan Injac:
Yeah.

Pete Wright:
I get up at 5:45 in the morning, and I’m ready to go to sleep at 10 o’clock. I’m done.

Srdjan Injac:
Yeah. You created that clock in your head that’s like, “All right, at this time we turn it off, and in the morning this is when we wake up.”

Pete Wright:
Yeah, yeah.

Srdjan Injac:
Once you get used to that sleep schedule, even now, if I have time to sleep in on Saturdays and Sundays over the weekend, I can’t. I wake up at six or seven. I can’t sleep past that, and I’ll try to go back to sleep. Sometimes I’ll fall asleep again, but most of the time I’m ready to go, because my body’s used to being up at that time. So you can’t make up that time when the weekend comes, like, “Well, I don’t sleep well from Monday to Friday, but that’s okay, I’ll just make it up on Saturday and Sunday.” It doesn’t really work that way.

Pete Wright:
Yeah, yeah.

Srdjan Injac:
It’s really hard for the human body to stay asleep just because you want to. It doesn’t mean it will happen.

Pete Wright:
This whole conversation just makes me think of a dear friend of mine who has a pretty serious sleep disorder, and as a result is in treatment for both narcolepsy and insomnia, which means he constantly falls asleep during the day and can’t sleep at all at night. So he’s medicated on both sides. None of this helps folks who are dealing with chronic, severe, diagnosed sleep disorders, and none of what we’re talking about should be considered—

Srdjan Injac:
[crosstalk]

Pete Wright:
—a viable tool. Talk to a specialist, please, if you’re dealing with this. But if you’re dealing with just—

Srdjan Injac:
Yeah.

Pete Wright:
—poor habits, some maladaptive behavior around your diet, your alcohol intake, your caffeine intake, your screen time, maybe you should be thinking about how your lifestyle and behavior impact your efforts at the gym, because all of that can help you—

Srdjan Injac:
That’s good.

Pete Wright:
—get better sleep. It’s completely connected, and it will help you see better results in the gym.

Srdjan Injac:
Yeah, definitely.

Pete Wright:
All right, this is good stuff. I actually have to come see you right now, but really I’m ready for a nap.

Srdjan Injac:
Yes.

Pete Wright:
That’s what this whole conversation’s done for me.

Srdjan Injac:
I actually took a nap earlier.

Pete Wright:
Oh no, you’re ready.

Srdjan Injac:
It felt great. I’m awake. It was perfect, that twenty-minute nap.

Pete Wright:
Yeah. Okay.

Srdjan Injac:
Yeah, yeah, I’m ready to go.

Pete Wright:
All right. All right. Well, thank you everybody for downloading and listening to this episode. We sure appreciate your time and your attention. And if you’ve got questions about training or sleep or recovery or how to make strength work in your life, we’d like to hear them. Just swipe up in the show notes and tap the link that says “Submit a question for the coach.” We’ll answer them on an upcoming episode. Don’t forget to subscribe and share. This is how we grow stronger together.

Thanks for listening to Build for Health, and we’ll catch you next week in the gym.