Exercise Cardio is King (?)

Cardio is king…

I hear this a lot. And although there is information out there explaining the true merits of cardiorespiratory exercises, there is still a prevailing narrative that pushes it as the surefire way to burn fat and lose weight.

So what is the simple truth?

First, Let’s Define Cardiorespiratory Fitness

The NIH says “Cardiorespiratory fitness (CRF) refers to the capacity of the circulatory and respiratory systems to supply oxygen to skeletal muscle mitochondria for energy production needed during physical activity.”

Put simply: for power, movement, energy, we need oxygen and the heart and lungs get it there. The stronger the heart and lungs, the more efficiently we can receive the oxygen we so vitally need.

Why it Matters

You may be thinking: Why does it really matter? I can breathe. I can get through my day with no issues. I don’t want to be an athlete. Why do I need to improve my cardiorespiratory fitness?

The reason it matters is because cardiorespiratory fitness goes way beyond pumping blood while you’re out for a jog. Not only does every cell in our body require that oxygen delivery to function, a quick look at OurWorldinData.org will reveal that the #1 causes of deaths in 2019 worldwide were cardiovascular (heart) diseases such as strokes, heart attaches, heart failures, arrythmia. This was followed by cancer; with #3 being respiratory diseases.

Cardio Starting Point

To start down a healthier path and lower your risk for disease, aim for 75 minutes of vigorous aerobic activity, or 150 minutes of moderate aerobic activity per week.

An easy way to self-asses your level of intensity is called Rate of Perceived Exertion (RPE). RPE follows a scale of 1-10, with 10 being maximum effort (i.e. and all out sprint for your life) and 1 being a leisurely stroll listening to the wind in the trees. When going for moderate intensity, aim for an RPE of 4-5. When aiming for vigorous intensity, you want an RPE of 6-7.

As you progress, and your heart & lungs do want progression, increase activity by 10% each week, and continue checking in with yourself and your RPE (which will also progress).

Regarding Fat Loss

When your body moves, you burn calories. So there is a benefit of potential weight loss there. And the higher the intensity, the more calories that will be expended. Walking at a moderate pace, can burn 4-7 calories per minute (according the National Academy of Sports Medicine).

So, ask yourself if your ultimate goal is achieving a number on the scale, OR if there is a body composition or image, type, size that comes to mind; and maybe you think that image will be obtained once the scale spits out a certain number.

Unsure? Do a quick internet search “same weight different body composition” or click the link below where I already did it for you:

Weight vs. Body Composition

Once you decide what’s most important, the scale number or the body shape, you will be able to decide for yourself the role cardio will play in your life. It is important, and does need to play a strong role. But I’m guessing most of us want the body composition change option vs. just the number on the scale. In body composition changes, cardio is not the king.



Although moving your body; going for a run, a swim, riding a bike, anything to get the heart rate up, will burn calories. It is not the most efficient way to change body composition.

However, just like the name says, it is amazing and essential for strengthening the cardiovascular & respiratory systems. With diseases of those two systems topping the charts of deaths, globally, it is critical to take action. There are, of course, situations out of our control, but exercise and fitness is not one of them; making our own risks of untimely death and disease, highly preventable.

We all have the same time in a day. The same time in a week. 10,080 minutes to be exact. And only 75-150 of them, per week, are necessary to get started. And if you’re already doing that, add 10% this week. Then next week, add another 10%. Strive for giving it 40-50% of your max effort or more.

Cardio may not be the king of changing your body composition and making your beach body dreams come true, but it is the King of the Heart & Lungs, and the King of Reducing Cardiovascular & Respiratory Diseases.

The Sneakered Sloth

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