Before we get into today's episode, if you want to actually improve your body composition and are sick of random workouts that just wear you down and burn you out, that's exactly why I build Evolo. Evolo is science-back strength training designed to help you build muscle, improve body composition, and feel better in your body without beating yourself up or living in the gym. You can try Evolo now for two weeks free if you visit evolofitness.com. Welcome to Fitness Rewired on the Dr. Shannon Show, a nine-episode capsule designed to close the gap between fitness culture and exercise science so you can see higher return on your effort and finally feel like you're doing enough. Many fitness beliefs come from marketing and tradition and don't align with current evidence. When you learn the truth, you can rewire your thoughts around fitness. That shift leads to higher quality actions, better results, and health you can actually sustain. I'm your host, Shannon Richie. Welcome to the show. One of the things I consistently hear from people is that Evolo, which is our strength training app, doesn't feel very hard. And so therefore, they're worried that it's not effective or they're worried that it's a waste of their time. And this is truly, I think, one of the biggest things that holds people back from actually changing their body is the belief that a workout has to feel hard to be productive. Many people assume that if they aren't exhausted or drenched in sweat or completely wiped out of it, they're going to be able to do it. If you're not sweating in sweat or completely wiped out, afterwards, the workout didn't count. But this belief can actually hold people back from seeing results because lifting workouts, which will have the biggest impact on your body composition, often don't feel exhausting. Your heart rate may not stay super high. You may not sweat much. And compared to a boot camp class or a cardio class, it can feel almost too calm, which makes people wonder if they're wasting their time. And this is why I'm explaining what is actually happening inside your body during different types of workouts, when and where, quote, unquote, hard has a place, and why understanding the difference between hard and productive can completely change your results while leaving you far less burned out and broken down. So this is all coming from my personal realization that I wish I had known 10 years ago. I used to prioritize hard and sweaty workouts every single day, sometimes twice a day. And now I focus on nutrition and muscle growth and moderate-ly dose cardio. My results have never been better. My results were so, are so much better than they were back then, even though I work out far less. I rarely break a sweat in my workouts. I certainly don't burn a ton of calories, but I have body recombed using this method three times now. So once before my first pregnancy, once after my second pregnancy, and I'm currently going through it for the third time now, it is so much more sustainable and effective, and you feel like you're working out a lot less hard. It feels so much easier to stick to. I want to scream it from the rooftops if you can't tell. But so much of us were taught that our workouts need to be grueling in order to work. And it makes intuitive sense, but it also comes from decades of fitness culture and is not aligned with the current science of how the body adapts. Exhaustion is an immediate and obvious signal that maybe we've done something uncomfortable, so it's proof that it's working. Strength training, on the other hand, doesn't provide that instant feedback. Progress like strength gains and muscle growth happens slowly, takes muscle about eight to 12 weeks to notice substantial gains. So people understandably struggle to trust the process. And that's why understanding the timeline of adaptation of how your body changes as you add resistance training is so important. It helps you recognize when you're actually on the right track. And if you want to know more about this, check out my body recomposition capsule, episode number two on the timeline of change, if you need to know more about if you're on the right track. But what is a hard workout really doing for you physiologically? Most people think of hard as breathless and sweaty and high heart rate, lots of muscles working at once, overall exhaustion, but sometimes it also may mean burning or shaking intensely. These sensations feel like they should be driving change, but they're often misunderstood. What people lump together as, quote, unquote, hard actually includes two different things, which I'm doing two separate podcasts on. So there's systemic fatigue and local muscular fatigue. And neither one guarantee body composition changes. I'll spend this episode talking about systemic fatigue and I'll talk about local fatigue in the next episode. So systemic fatigue is that kind of non-specific exhaustion that overall tired, that breathless, that sweaty, that I have to crawl out of the gym. And then the next episode, I'll talk about the burn, which is local fatigue that can also give you a false sense of effectiveness. So systemically fatiguing workouts, think things like boot camps or heated workout classes or long, really high intensity cardio sessions. These workouts absolutely challenge your body and your body will adapt, but not necessarily in the way that people expect. When effort is spread across many muscles and systems at once, the adaptation is spread out too. So your heart and lungs become more efficient, your endurance improves, and your body gets better at delivering oxygen and fuel to your working muscles. Those are valuable health adaptations, but that's mainly a cardio and conditioning stimulus, which isn't the primary driver of any substantial body composition changes, which is ironically typically the reason why people do those workouts. Body composition changes happen when you build muscle and lose fat. The misconception is that these boot camp hard workouts do both at the same time. They help you burn fat and they help you build muscle because maybe you're lifting weights and you're really out of breath. So you're out of breath, which means you're burning fat and you're lifting weights, which means you're building muscle. But unfortunately, neither is happening very effectively. This is because mechanical tension and treating close to failure, not sweating or calorie burn or exhaustion, is the main stimulus that builds muscle. You may stop an exercise because you're out of breath or globally fatigued, not because the targeted muscle reached its limit. And you're out of breath or you're fatigued, but that doesn't necessarily create a lot of fat loss. We see from many studies that exercise alone doesn't substantially lead to much fat loss. And as we talked about in the last episode, calorie burning doesn't really make a huge difference in fat loss either. So these hard workouts may be making you better at working out and they may be improving your overall cardiovascular system, but they are a lot of effort for low payoff if body composition changes are your goal. So we do have some data about this. There was a study in 2017 that looked at a group of people who did body pump classes. Body pump classes are barbell classes and I think you use some dumbbells as well. And it's higher rep training. You're going to the beat of the music, but you are lifting weights and you are lifting what some people would consider heavy weights. So it's full body strength training. The participants did three times a week for 12 weeks. And after 12 weeks, they found no significant body composition changes, but 12 weeks is really when you should start to see muscles growing if you are simulating the muscles properly. So it's not that the study wasn't long enough. They were also hitting each muscle group three times a week. So we know it wasn't a frequency problem. The volume in my opinion from someone who used, I used to teach body pump actually, if in fact is that the reps are too high to drive significant muscle growth. But those classes feel really hard and potentially sweating and you're lifting weights. So they give you the illusion that they are either burning fat or building muscle or both. But what we saw from the study is that that wasn't really happening. And my opinion, it's because you're more focused on endurance than true muscular failure. So the adaptations are different. You for sure may get a little stronger and have better endurance. And if it's helpful for you to stay moving, by all means go for it. But those changes don't necessarily translate to meaningful body composition changes if that's your goal. What you are limited by is what will adapt. So if you are limited by overall exhaustion, your cardiovascular system will adapt. If you're limited by endurance, holding something or doing exercises for a really long time, your endurance system will adapt. Your muscular endurance will adapt. If you're limited by muscular failure, your muscles will adapt and grow. And that is what provides body composition changes. So if you're like, oh gosh, I don't know if I am limited by systemic fatigue or if I'm limited by endurance or if I'm limited by true muscular failure. Maybe you're lifting weights in your workouts, but you're not really seeing the changes. Number one, it takes at least 12 weeks, so stick with it. But if you've been lifting for longer than that or you're going to group fitness classes, how do you know if it's systemic fatigue or if you're truly lifting close to failure to drive muscle growth? So number one, a few things. Go back to the basic principles of hypertrophy, which means getting close to failure in under 30 reps. If you could physically do more than 30 reps of an exercise, it isn't heavy enough to drive significant muscle growth. Number two, notice if you stop an exercise because of overall fatigue. So maybe a lot is burning at once. Maybe you're doing an exercise that's upper body and lower body, maybe like a lunge with a bicep curl. And you stop that exercise because your legs are burning and your arms are burning, but it's non-specific fatigue. You stop because of overall your body feels tired, but you know deep down you could keep going in those exercises. It's just that it's getting really uncomfortable. You're getting stopped by the burn. You're not getting stopped but because the muscle is truly at failure. And then number three, if you truly think you are stopping an exercise because you are at failure or one to three reps shy of failure, try what we call the rest test. This is one of my favorite things that really helps you differentiate between systemic fatigue or local fatigue and true muscular failure. So after your final rep, let's say you do 12 reps and your 12th rep, you're like, okay, I don't think I could do anymore. Drop the weight, shake it out for a little bit and then pick up the weight and try to do more reps. If you could do three or more reps, you were fatigued, you were not at true muscular failure. And again, it's not to say that not getting to true muscular failure is that, it just means, okay, just go up and wait next time. It's no big deal, but it is a really valuable way to see are the workouts that I'm choosing, are the exercises that I'm choosing actually moving the needle towards my goal. So now I wanna say systemic fatigue is not bad. Systemic fatigue does have an important role in your health. Whole body stress improves your cardiovascular system, your metabolic health, your overall work capacity, and being better conditioned helps you tolerate strength training better. So does that mean that these types of classes where you're lifting weights and limited by overall fatigue, can those replace cardio? I would say, no, I would not recommend that you do those types of workouts in place of more true cardio. Highly fatiguing workouts like bootcams and many group fitness classes with weights or heated workouts can improve cardiovascular fitness, but they do so differently and often less efficiently than just traditional steady state cardio or interval based cardio. Cardiovascular adaptations are primarily driven by sustained elevations in heart rate and cardio output that challenge the heart and vascular system in a predictable way, which is why structured aerobic training reliably improves measures like your B.O.2 max and your stroke volume. In mixed kind of full body fatiguing workouts, heart rate often fluctuates as muscular fatigue, coordination demands, or transitions between exercises becomes the limiting factor, meaning cardiovascular stress is inconsistent, even though the workout feels extremely hard. These sessions therefore tend to produce a blend of adaptations. So you get some endurance improvements, you get some muscular endurance and general work capacity, but usually provide a weaker cardiovascular stimulus, then dedicated cardio and a weaker muscle building stimulus than focused resistance training. In other words, they train many systems at once, but not as specifically or efficiently as separating conditioning and strength work. So this is why I just recommend separating your cardio from your strength training. You'll see a lot better results and you'll probably feel a lot less worn down if you do your cardio work separate from your strength training work. Cardio work, I recommend about 150 minutes of light to moderate intensity cardio. Within that 150 minutes, you could even sprinkle in some higher intensity cardio, so some interval work, brief short interval work, maybe once or twice per week. We have our intervals class, which is about a 10 to 15 minute class. All you need is one of those a week to have marked improvements in your cardiovascular endurance and your conditioning. But let's say you are separating out your strength training from your cardio. You're not expecting your strength training to feel quote unquote hard, because what you wanna be limited by is your muscles. And when you're limited by your muscles, you won't be completely gassed, you won't be out of breath, you likely won't sweat very much, you're not gonna burn very many calories. But what if even then you're doing that type of work and you're still noticing systemic fatigue in your workouts that's limiting you from getting close to failure? Let's say you're doing lunges or step ups, and you're like, I know my glutes could do more, but I am gassed, like I am out of breath, I'm puffing, and I feel like that is what's limiting me, even though I'm lifting weights, I'm not doing anything crazy, what do I do then? What I recommend is just taking a break, just taking longer rest periods in between each exercise. What we do in FLO is we do super sets. So we're alternating muscle groups as one rest. So let's say we work chest, we're doing chest presses, and as your chest rests, we're doing rows and working the back. And this helps to keep the workout efficient and is scientifically shown to be just as effective for muscle growth as resting completely between sets. But even still, taking short breaks in between exercises, pausing the video, and even taking 30 seconds of a break may help you get even more out of each lift. When I take class, I sometimes pause the video and take breaks if I'm out of breath, especially in lower body lifts. And what I find is that makes the next set so much more effective because I kind of have reset my system, so I'm not as limited by systemic fatigue, I'm truly limited by the muscle. And when you do that, you can recruit a higher percentage of the muscle and your workout is more effective. So in short, separate your cardio and your strength training. Don't worry about your strength training being super exhausting and depleting. It's not going to feel like that because when your workouts are super exhausting and depleting, you're limited by that, not by true muscular failure. Cardio is absolutely important for your health, so don't neglect your cardio. Around 150 minutes of light to moderate cardio each week is great. I do a blend of walking, I'll take or teach our steady state class, and then I do our intervals class once per week, which is true high intensity work that's only 10 minutes long. And what I've found is that cardio, if you separate it and do it intentionally and you're not overdoing it, it can actually improve the effectiveness of your strength workouts because when you are more conditioned overall, you're less limited by systemic fatigue even in your strength workouts. I've added back our intervals class after my second pregnancy, and I feel a huge difference in my ability to lift without being limited by systemic fatigue. And I'm only taking that class once a week and it's 10 minutes. It's a combination of some sprit work and some hit work, very, very short, but very high intensity. And that is making a huge difference in my overall strength stimulus while being low enough dough so that I can easily recover from it. We don't want a ton of high intensity cardio, we just want enough so that your body is adapting and that can improve your strength training sessions. And your strength training sessions can feed and improve your cardio sessions, they're really symbiotic. So here's the takeaway, exhaustion changes your system, failure changes your body composition. Conditioning is valuable for your health, but you're better off separating conditioning from cardio training. Your strength training sessions should not feel globally hard because that dampens the signal and makes the work less effective. Do your dedicated cardio 150 minutes of blend of intensities and strength training separately. You'll see better results, your workouts will feel less brutal and your body will feel less broken down. I hope this was helpful for you. Again, understanding this has been super transformative for both my mindset and my physical body. Tomorrow we are talking about the second half of this conversation, which is about local fatigue. So why feeling a burn isn't necessarily tied to muscle growth and why these types of workouts are so-called toning or sculpting will discuss what that means, where this comes from, what are these burning workouts doing, are they worthless? We'll discuss it all tomorrow. See you then.
