Chronic cardio is forcing your body to kill you

Before reading theism please be advised I am not the author of this post. I found it here ( http://crossfitmeanstreets.com/2010/09/08/chronic-cardio-is-forcing-your-body-to-kill-you-and-how-you-can-save-yourself/

And I thought it would be fun to share and get others point if view.. Read on!


Some of you may have looked at the title of this article and balked, “What? I just ran the LA Marathon and I feel great! I’m the fittest person I know!” Just by that statement alone, you would do well to read on. The fact of the matter is that popular culture has fundamentally altered what “fitness” really means, and in doing so has created the exercise world’s equivalent of the obesity epidemic: chronic cardio. This article will attempt to explain what I’m talking about, why it is such a problem, and what you can do to improve your lot.

First, you may be wondering what I mean by “chronic cardio.” I actually borrow this term from Mark Sisson, whose book “The Primal Blueprint” is a foundational work for this article and a must-read. Basically, what he and I are talking about is the concept of sustained moderate to high heart rate for long periods of time and its deleterious effects on the body both in the short and long term. As we have evolved over millions of years to the form we are today, our species had to survive some pretty nasty stuff, like faster, stronger predators, and the wrath of Mother Nature, among other things. We are still largely governed by the same mechanisms that kept those ancient humans alive all those years ago. The only issue is we don’t really have to worry about lions roaming our office hallways or waiting out a food-scarce winter anymore. We also don’t have to hunt our food or walk vast distances to find things like water, shelter, and fuel. This is an issue mainly because your body, despite all that is going on around you, still thinks and acts like you do.

This is where the endocrine system comes into play. Without getting too much into detail, it is the system of hormones that regulates basically everything your body does, from growth to death, and it is very finely attuned to the external cues your conscious actions provide it. But since the endocrine system itself is not consciously aware of its surroundings, it doesn’t know that you went to Starbucks and got a double grande mocha or that you just ran 26.2 miles for fun. All it sees is the final product, the chemical processes within the body at the microbiological level that really determine your health and well being at all times. And when it comes to running, the endocrine system doesn’t think, “oh lovely, he’s training for a marathon, good for him”, it thinks “oh ****, I’m being chased by a lion” and acts accordingly.

The body’s most appropriate response to a bout of running is to freak out. Among other processes, most important to this article is the release of a boatload of cortisol, a stress hormone, into the blood stream. This hormone causes a process called gluconeogenesis to occur, which in layman’s terms boils down to “your body eats your muscle to create glucose.” This is because long duration activity utilizes the oxidative metabolic pathway primarily, which requires quite a bit of glucose to function. Normally if you are simply running away from something a short distance, the glucose hit won’t be unmanageable. But say you run 10, 20 miles, even a marathon. Your body will be so strapped for glucose that it will burn anything and everything it can get its hands on, including muscle tissue and fat. Hence why, physically, runners look both lean and emaciated; their bodies have simply scrapped them for parts. It also has a whole host of other nasty side effects that all boil down to your body making a short term sacrifice for maximum short term performance in the interest of survival (if you’re interested in the list, the Wikipedia article on cortisol should be enlightening). The problems emerge because there is no way to forewarn your endocrine system that you’re going to go running, so it automatically thinks you are being chased by a lion every single time (because it has no idea why anyone would willingly go running for no reason) and goes into life saving mode every single time. If you are a logical human being, at this point the pieces may be starting to come together. If not, I can lay it out for you: doing something that is mildly detrimental a lot will make it a lot more detrimental. You take a process that is designed to save your life in a pinch, and turn it into a multiple times a week occurrence. You, the chronic cardio person, are basically tearing yourself apart from the inside out in the name of fitness, and you’re not even getting fit while doing it (Don’t believe me? Ask an Olympic marathoner to do a pull up).

So at this point you may be asking yourself, “Well now that I’ve wasted years of my life, what can I do to change it?” and the simple answer is take advantage of your body’s own way of making itself fit. This process, also endocrine related, is fully (and, in my opinion, best) covered by the Crossfit program. The name of the game is intensity. In the same way that chronic long duration, low intensity running triggers your body to freak out, short to medium duration, high intensity workouts trigger that same endocrine system to move into kick *kitten* mode. This is the level at which the endocrine system thinks “damn that was hard” and produces hormones to build muscle, physical capacity, blood vessels, and so on, all with the intent on making you stronger so the next time you are just a little bit better than before. Do this enough times with a large enough variety of things, and you will arrive at a level of fitness most people currently living on this planet only dream about. That is the essence of Crossfit, and it works. So get off your treadmills, tell Gold’s Gym to suck one, and head over to your local Crossfit affiliate. You’re welcome for saving your life.