A lot of bodybuilders fear adding cardio into their workouts. You might even see them walking at a slower pace, thinking that anything above that would be considered cardio. While this may be a more extreme reaction than your average bodybuilder, it doesn’t change the fact that there are a lot of misconceptions about cardio and its effect on muscle growth.
We’re about to dive into the major types of cardio: low-intensity cardio, moderate-intensity cardio, and high-intensity cardio. We’ll list the advantages and disadvantages of all three for bodybuilders, and we’ll show you just how you can use cardio to sculpt your body however you want, with zero muscle loss, guaranteed.
Moderate-intensity cardio is neither too low, where you’re barely burning any fat, nor too high, where you’re panting and gasping for air within a minute or two. This type of cardio is actually where you get into your fat-burning zone. By moderate intensity, we mean that you’ll get to about 65% of your VO2 max, or around 65%-70% of your heart rate max. When you’re in that zone, studies show that you actually burn the most fat.
But don’t stop reading the article and focus only on moderate-intensity cardio, because there’s a catch. Long-term studies have actually determined that moderate-intensity cardio isn’t actually what gets you the leanest.
That’s because as you go up in cardio intensity, your reliance on fat as fuel goes down, and your reliance on your carb stores shoots up. So if you’re doing very low-intensity cardio you’re burning mostly fat, albeit at a very low calorie expenditure.
However, if you reach 65% of your heart rate max, which is around moderate-intensity cardio, you’re burning about 50% fat and 50% carbohydrates. If you’re doing a high-intensity cardio workout, like a full power sprint, you’ll be burning almost all carbohydrates.
That’s why a lot of bodybuilders tend to stay in that intensity–it helps you get leaner, and improves your overall cardiovascular conditioning. However, it does come with a pretty heavy drawback.
Numerous studies have shown that the sweet spot for decreasing muscle mass, strength, and power is that same sweet spot for the most fat burning state. In other words, moderate-intensity cardio has been shown to decrease muscle mass, strength, and power.
Not only that, it causes you to decrease your metabolism as well, making it harder to make gains. That’s why a lot of bodybuilders are so scared of adding cardio to their workouts. After all, who wants to lose their muscles?
What’s the alternative then? If you look at low-intensity cardio, it sounds as if you’re losing calories for free. Just by walking for an hour a day every single morning, you’ll be doing a low-intensity cardio session.
What ends up happening is that during that hour walk, you don’t counter adaptations to gaining muscles, so you’re essentially just burning your calories without overreaching and burning your muscles.
The advantage is that such an activity is very low stress, improves your insulin sensitivity, and doesn’t decrease your muscle, the downside is that you won’t end up burning that many calories, at most around 250-300 extra calories.
Here’s where you’ll get the most benefits, if you can handle it! We actually found that very high-intensity cardio, meaning where you’re all out sprinting, actually causes the most fat loss, despite the fact that you’re burning mostly carbohydrate stores.
That’s because when you deplete your carbohydrates to a high extent, it triggers increases in mitochondria, that fat-burning furnace in your cell. In addition to that, since you’ve depleted your carbohydrate stores, your body will tend to burn more fat for fuel the rest of the day.
Even further than that, your metabolism will be up for around 24-48 hours after a high-intensity cardio session, and the best of all? You’ll be burning the most long-term fat, without interfering with your gains.
Not everything is sunshine and rainbows in the high-intensity cardio world. You have to treat a high-intensity cardio session as a weight lifting session, as if you do sprinting workouts every day, it can lead to a severe case of overtraining.
We recommend not going all out more than twice a week, and definitely no more than three times. Otherwise, you’ll end up overreaching and compromising your gains on your leg muscles.
Our Recommendations for Cardio
We actually recommend combining high- and low-intensity cardio sessions, and only trying moderate-intensity cardio when you’ve got no alternatives and need to switch things up.
So how do you actually combine the two? Simple. Sprint all out and increase your adrenaline levels before starting your morning hour-long walk. This will help you burn more fat during that walk. You will also have depleted your carb stores so you’ll be burning fat at a higher rate!
We hope this article helped you figure out just how cardio can be beneficial to your bodybuilding journey!