Does Too Much Cardio Slow Your Metabolism?

Nikkiey: You've probably heard that too much cardio is bad for you. Cardio in the morning, group fitness at night. You don't burn as many calories from cardio as you might think. I was totally out of shape, with my body composition at the highest fat percentage I'd seen in years. But what does that mean exactly?

In this video, I'm going to break it down for you and explain why too much cardio could be hindering the results you want to see with building more muscle to be more toned and seeing changes in your body composition, and how to balance cardio properly with strength training.

First, let's talk about why cardio is important for weight loss. Cardio exercises such as running, cycling or swimming are great for burning calories and promoting weight loss. Cardio is great for your overall cardiovascular health. However, when it comes to building muscle and changing body composition, cardio alone, or doing too much of it, may not be the best approach.

Too much cardio without incorporating strength training can lead to muscle loss, which can be counterproductive to the type of results you want to see within your body composition. It won't give you a toned, lean look. You need muscle mass to achieve that look. Instead, it will leave you looking skinny fat, with no muscle tone.

When you engage in cardio for long periods of time, your body starts to break down muscle tissue for fuel instead of using fat. This can lead to a decrease in muscle mass and metabolism, making it harder to lose weight and burn fat in the long run. So if you're doing excessive running and cardio, your body may start to adapt to that constant demand, and you may end up burning fewer calories than you expect.

This is known as the adaptive response of the body. As muscle mass decreases, your body will start to become more efficient at completing the same cardio exercises, leading to fewer calories burned per cardio session. This can make it harder to continue losing weight and burning fat. And it's why, if you're a cardio bunny yet not seeing the results that you want, you will need to increase the duration or intensity of your cardio workouts to see results.

Let me dive even deeper into this explanation. If you are doing an activity that requires very little strength and muscle, and you're doing a lot of it, aka cardio, and that activity requires burning a lot of calories, then your body will start to adapt. It will start to slow down, as I mentioned earlier.

So our metabolism has this range of how many calories it can burn. It can make itself more efficient or less efficient with calories. When your body becomes less efficient with calories, it wastes more energy, wastes more calories. You want to be less efficient. When it becomes more efficient, it conserves more energy, more calories, so it holds on to more calories.

Here are some more examples of what I mean with this explanation. I'm going to use cardio versus strength training. With overuse of cardio, your body recognizes, okay, we're burning a lot of calories here during this activity. We need endurance. We don't need a lot of muscle and strength. So let's learn how to conserve calories by paring down muscle, aka slowing down your metabolism, so you can become a more efficient endurance cardio machine.

Whereas with strength workouts, your workouts don't really burn that many calories, and the calories burned on your fitness watches shouldn't matter for this reason. But those workouts require strength and muscle. Now your body is like, let's build this muscle, and we can be less efficient with calories so you can build that muscle, which is what will speed up your metabolism and help aid in fat loss.

Here's a visual for you guys. You see all these people who routinely come into the gym, and they do one hour, two hours of cardio on all different kinds of cardio equipment: StairMaster, treadmill, elliptical. They may be paying attention in such fine detail to their calories during the day and how much they're burning during their workout session via the measuring tools that are built into these machines. For example, I ate 1,800 calories today, and I burned 600 calories during this cardio exercise on my treadmill. That number on those machines has virtually absolutely nothing to do with anything.

What they don't realize is that over a long period of time doing the same exact thing, they have actually been slowing down their metabolism by conserving calories for that activity. You train your body to get better at what you are teaching it to do, or what your workouts are doing. So if your workouts are high calorie burning and require very little muscle, aka cardio, then your body learns to adapt to that workout by slowing down its metabolism.

Strength training is essential for building muscle, increasing strength and so much more. By using resistance to target a specific muscle, such as weightlifting, resistance band training or bodyweight exercises, you're causing micro tears in the muscle fibers, which then repair and grow back stronger and bigger. This is how you build muscle and increase muscle mass, which is what being toned means, and it's important for overall health, strength and your metabolism.

Strength training has a metabolic benefit, as I've already explained, which is important for burning fat. A higher muscle mass means a higher metabolism, which can help you burn more calories even at rest. This can be achieved by progressive strength training, which means consistently increasing the weight and reps you do and keeping it challenging for your muscles.

Another issue with excessive running and cardio is that it can lead to a condition called overtraining. When you're running for long periods of time, your body is in a constant state of inflammation, which can lead to muscle breakdown and can cause hormonal imbalances in the body. This is completely counterproductive when your goal is to build muscle. The term overtraining refers to a state when the body is constantly fatigued and unable to recover from exercise, which makes building muscle almost impossible.

Instead of excessive cardio, try to balance the load with shorter, more intense sessions. HIIT is a good recommendation here, but there is a way to do HIIT right. You don't want to overdo that either. Shorter, more balanced cardio sessions will burn more calories and promote muscle growth. And you'll want to focus on progressive strength training. This way you can increase the weight and reps you do and keep challenging your muscles.

Another really important thing here is eating enough protein to fuel muscle growth. It's crucial. Protein is the macronutrient king, as protein is essential for muscle repair and growth. Make sure you're getting enough of it throughout your daily diet.

Lastly, it is important to monitor recovery time and schedule rest days so the body can heal and grow. You'll always hear me say, you break down muscle in the gym and you build it in the hours and days following with proper nutrition, recovery and rest. Remember, recovery is just as important as training, and your body needs time to repair and build muscle so you can look more toned.

In conclusion, too much cardio and not enough strength training can negatively impact your ability to lose fat and build more muscle by leading to muscle loss, the adaptive response and overtraining. To achieve your goals, it's important to strike a balance between cardio and strength training, focus on progressive strength training, eat enough protein to fuel muscle growth, and monitor recovery time and schedule rest days so the body can heal and grow.

Thanks so much for watching today, you guys. Be sure to subscribe to our channel for more tips on fat loss, muscle building and overall fitness. Don't forget to comment below with any questions or suggestions that you have for future videos.