In this podcast I talk all about cardio: how much you should do when you’re dieting to lose fat, how much for building muscle, how much is too much, what types are best, and more…

Episode Transcript:

Mike: [00:02:02] Hey, Mike Matthews here from Muscle For Life and Legion Athletics and in this video podcast, I want to answer a simple question that I am asked fairly often, and that is: should you do your weightlifting or your cardio workouts first?


[00:02:19] In other words, you are going to do both some weightlifting and some cardio in the same gym session, the same workout session. How should you go about it? Some people say that you should start with your cardio because it’s a good way to warm up and cardio, especially intense cardio is particularly hard after weightlifting and after intense weightlifting.


[00:02:42] Now, other people say that you should do your weightlifting first because you want to be as fresh as possible for those workouts. You want to have as much energy to give them as possible. And if you waste some of that energy or use up some of that energy on your cardio, then you are not going to be able to progress as easily or as quickly in your lifting.


[00:03:03] Now, other people still say it doesn’t really matter. Practically speaking, it doesn’t matter, just do whatever you like most.


[00:03:09] So who’s right? Well, my answer, short and sweet, and then I’ll get into why, is that: if your goal is to gain muscle and strength as quickly as possible, you want to do your weightlifting first. And in fact, if you really want to gain muscle and strength as quickly as possible, then you want to do as little cardio as possible. 


[00:03:32] In addition to the timing of it, you also want to keep your cardio to a minimum for two reasons. The first reason is cardio is fatiguing. And the more cardio you generally do, the more general fatigue you are going to experience and that is going to make it harder to progress in your weightlifting workouts.


[00:03:51] And reason number two is more of a long term reason. There is research that shows that cardiovascular exercise interferes with some of these cellular signaling related to muscle building. So what that means is that: the more cardio you do, the more impaired your body’s muscle-building machinery is. And even if the effects are fairly slight, they can add up to a significant reduction in muscle and strength gain over the long term.


[00:04:22] A simple way to look at this is: simply that, resistance training and cardiovascular exercise send very different signals to the muscles in terms of what type of adaptation is supposed to occur. And so, for example, if you want maximum strength gain and maximum hypertrophy, if that’s the adaptation that you’re going for, you want to send as clear of a signal over and over and over to those muscles as possible. And that is the signal that resistance training produces.


[00:04:56] Now, cardiovascular exercise sends a very different message to the muscles in terms of how they should respond to the stress. Getting bigger and stronger wouldn’t be an appropriate response because it would not help you run more miles. In fact, it would get in the way of your ability to run more miles because you’d be carrying more weight and you’d have a lot of muscle that is optimized for producing a lot of force quickly, as opposed to muscles that are very resistant to fatigue and can contract repeatedly for long periods of time without crapping out.


[00:05:35] And while we are on the topic of cardio and muscle building, generally, it’s worth noting that several studies have shown that the longer your cardio sessions are, the greater the interference effect is. And that is simply a technical term, by the way, for cardio’s negative effects on muscle building. Interference effect is how it is referred to in the scientific literature.


[00:05:58] Now, all that does not mean that you should not do any cardio if you want to get jacked. There are a few good reasons to do cardio, even if your goal is to gain muscle and strength as quickly as possible.


[00:06:13] Now, the first one is: research shows that cardiovascular exercise can provide some health benefits that we probably can’t get from resistance training alone and they are primarily cardiovascular in nature, big surprise. So while we do know that resistance training is good for our heart health, there’s some evidence that doing some cardio in addition to the resistance training is even better for our hearts.


[00:06:39] The second reason is there is evidence that improving your cardiovascular fitness can also improve your recovery times in between your resistance training sets. So let’s say that you normally and you take two or three minutes to feel ready to give it your all in your next set. You know, where your heart rate has come back down into a normal range, you’re not breathing too heavily anymore and you just feel generally ready to go.

If it takes, again, two or three minutes currently, if you were to improve your cardiovascular fitness, there’s a good chance that you might be able to shave, let’s say, 30 seconds off of that. Which you then could use to get more work done in the time that you have for your resistance training workouts.


[00:07:27] And the third reason why meatheads should consider including cardio in their routine, whether they are cutting, bulking, or maintaining is: when you’re cutting, it helps you burn fat faster, of course, because it simply increases energy expenditure. And especially in the case of something like high-intensity interval training.

And, you know, I’ve written about that and spoke about that extensively, so I won’t go off on that tangent. If you want to maximize fat loss, do some HIIT. Maybe an hour and half, two hours max per week. And if you don’t want to do that, for whatever reason, I recommend going to the opposite end of the spectrum and simply adding some walking in your routine.

The reason being is walking burns 300 to 400 calories per hour and is very low stress. It’s very low impact. It is not going to cut into your recovery. And it is not going to interfere much, if at all, with your resistance training. So that interference effect, and this has been shown in studies, the interference effect in the case of walking is basically nonexistent. It’s when you get into stuff like jogging, you get to that level of intensity, regardless of the modalities when you start to see it more.


[00:08:37] And as far as maintaining and lean bulking goes, including cardio in your routine, again, even if it’s something as simple as a few hours of walking per week, there’s evidence that it can help mitigate fat gain. It can make you more resistant to fat gain, primarily by improving your body’s, improving your muscles ability to burn fat for energy.

And by the same token, by keeping your body’s fat-burning machinery running well, so to speak, including cardio in your maintenance and or lean bulking, your teens can also make your cuts faster. You can shave off probably a couple weeks from your post maintenance or post lean bulk cuts.


[00:10:47] All right. Now that we have all that under our belts, let’s finish where we began with the primary question of this video podcast, which is: should you do weightlifting or cardio first? Now, I said that you should do your weightlifting first. And now I want to quickly explain why.


[00:11:03] Now, physiologically speaking, muscle growth is initiated primarily by a number of anabolic signals that occur after your resistance training workouts. And you can think of these signals as switches. Now, as you’ve learned, cardio can interfere with some of these switches, make it harder to turn them on or even turn some of these switches off.

Now, that information has led to a theory that it would be better to do cardio before your weightlifting or before your resistance training, because it’s the resistance training that turns those anabolic switches on, and if cardio can interfere with that, then do it when those switches are off, which would be before your resistance training workout.

So you just get it out of the way and then you are free to do your resistance training workout and then those anabolic signals can kick in unimpeded by the cardio. And if you flip it around, these people say that you are basically first, doing the resistance training and then you’re starting up your body’s muscle-building machinery and the processes begin. And then you do the cardio and it interferes with all that. And it’s a reasonable theory, definitely worth investigating. But I do not support it for two reasons.


[00:12:15] The first one is that while research shows that longer, like 30 plus minute cardio workouts, most definitely impair with the post-workout anabolic signaling we just spoke about. Shorter cardio workouts, like under 30 minutes, and if you want it real safe, 20 minutes or less, do not seem to have these same effects. And the second reason is something I mentioned a little bit earlier, and that is just general energy levels and general fatigue levels.

So if the cardio that you’re doing is at least a moderate intensity and you’re doing at least 20 minutes of it, that is going to get in the way of your weightlifting workouts to some degree. If you were to do your weightlifting first, you will have a better workout than if you were to do it after 20 to 30 minutes of moderate or higher intensity cardio.

And because mechanical tension is the primary mechanical driver of muscle growth and progressive overload is the best way to subject your muscles to more and more mechanical tension. And of course, what that really comes down to is getting stronger over time, progressing. I spoke a couple podcast episodes ago about double progression, a simple model that I like to use.

But regardless of whatever model you’re using, it is going to involve lifting heavier weights in a given rep range over time. And that is your primary goal in your resistance training workouts. So anything that gets in the way of that is going to significantly hinder muscle and strength gain.


[00:13:53] So when you consider all that, there is a significant downside to doing your cardio before your resistance training or before your weightlifting, which is slower progress in your resistance training and no real downside to doing it after. Because if you keep it short, which I would recommend anyway, you are not going to interfere with those post-workout anabolic signals to any market degree.


[00:14:19] And that is not just theory either. This has actually been demonstrated in a number of scientific studies. For example, one was published in 2016 and it was conducted by scientists at the University of Uveskila. And what they did is: they took 42 men and they split them up into four groups. Group one was morning cardio, followed by weightlifting.

Group two was morning weightlifting, followed by cardio. Group three was evening cardio, followed by weightlifting. And group four was evening weightlifting, followed by cardio. And everybody did the same workouts. For the cardio workouts, it was some medium intensity stuff, as well as some high-intensity stuff.

And for the resistance training, for the weightlifting, it was some full-body workouts that progressed from lighter to heavier weights throughout the duration of the study. And after 24 weeks, what the researchers found is that the people who did their weightlifting first gained a bit more strength over that period than the people who did their cardio first.


[00:15:22] So if you can do your cardio workouts after your resistance training workouts and you will minimize the cardio’s negative effects on your muscle building and your strength gain. Even better than that, I should note for a wrap up here, is doing your cardio and your resistance training workouts on different days. And if that’s not possible, separating them by at least six hours.


[00:15:47] And the reason being is a couple of studies have shown that separating your resistance training your cardio workouts by anywhere from 6 to 24 hours can help further mitigate the interference effect and thereby maximize the anabolic response from your resistance training workouts.


[00:16:06] So, for example, what I do is when I have lifting and cardio on the same day, which only really do when I cut by the way, I’m maintaining and currently I do cardio twice per week. I do it on Saturday and Sunday, but I’m not lifting on those days. I lift Monday through Friday. Sometimes I’ll throw in an extra cardio session sometime in the week, but usually, it’s five days of lifting and two days of cardio when I’m maintaining and lean bulking.

But when I’m cutting, I get up to four cardio sessions per week, which means, of course, I have to couple on the days that I’m lifting. And on those days, what I do is, I lift first thing in the morning, I go down the street and go to a gym and do my weightlifting workout, and then I do the cardio at night. So the weightlifting workout maybe starts at seven, seven-thirty, and then twelve hours or so later I’m doing my cardio and I do it here at my house. I have an indoor bike downstairs and I just do my cardio after work.


How Much Cardio You Should Do (and How Much Is Too Much)

The Worst Way to Lose Weight

The Top 3 Reasons to Do High-Intensity Interval Training

How to Change Your Body Weight Set Point

How Much Muscle Can You Build Naturally?

What did you think of this episode? Have anything else to share? Let me know in the comments below!