A common site in any commercial gym: New member walks in, finds the treadmills. They are oblivious to what they are doing, but don’t want to ask for help. They look at the machine to see what they should be doing, and see this well-heeled chart stuck on the side of the display, same as it has been for years:

They see this and say to themselves “Well I want to lose weight and this says that I need to have a heart rate of 100 beats per minute to lose fat, so I guess I’ll do that.” They start walking on the treadmill (very slowly, because they don’t want to work outside of the “Fat Burning Zone”), and spend a good hour each second day doing this for the next three months. They notice after all this time that they haven’t lost any weight, and in fact they have actually gained a few pounds!!Now the thing charts like these never tell you is that the “Fat Burning Zone” will not result in any weight loss whatsoever.

“But…but…but, the machine said it would!!” Well, the machine is a big fat liar that didn’t tell you the whole story.

Let’s say you’re driving a car and you want to get where you’re going using the least amount of fuel possible. To do that, you’re going to drive fairly slowly. Sure, you’ll take hours longer to get where you want to go, but you’ll burn through less fuel doing so. Let’s say you get behind the wheel and want to go 170 down the QE2. You’ll be out of gas pretty quickly, with a fuel economy that will make Hummer owners blush with envy. The point of this is that if you go slow with your cardio in the “fat burning zone”, which is typically set to between 50-60% of your heart rate maximum, you become a highly fuel-efficient vehicle that doesn’t burn very many calories at all. Sure most of them will come from fat, but when one gram of fat contains 9 calories, a 1000 calorie workout will only burn 111 grams of total weight, or the equivalent of 0.05 pounds of body weight, and it will take you roughly 4.75 hours to burn this many calories in one workout.

You’re not going to lose any weight by doing this!!!

So why does everyone still say that the slow method of cardio is the fat burning zone? Well, they seemed to glom on to the fact that at low intensities, fat is the predominant energy source, regardless of how many calories are burned. Take the following graph that shows fuel usage from different fuel sources at different intensities (legend: glycogen and glucose means carbs, triglycerides and FFA means fats).

It showed that at really low levels of exertion, you’re burning pretty much 100% fat, where at the higher intensities, you start burning a greater percentage of carbs for your energy and your fat burning decreases. Cool, right?? Guess it means you should do long slow cardio to lose weight, right?? Did you look to see the total energy expenditure, though? 100 CALORIES (note, this is 100 calories, where the energy we know is the unit of a kilocalorie, meaning this is really 0.1kcals per kg body mass per minute)!!!! That’s a friggin lick of a chocolate, man!! You can’t lose weight doing this!!!

When we bump it up to 85% heart rate max, the caloric burn is tripled, with more than 2/3 coming from carbs. Since carbs become stored if they aren’t used quickly, this is a preventative measure. Additionally, when stored fat is broken down to replace used up carbs, we get the fat burning effect we’re looking for, at three times the rate of the “fat burning zone.” Burning the free fat is great and all, but it won’t result in much mass being lost unless we mix a little bit of carbohydrate “lighter fluid” into the mix to get the fat burning process started. PLus, when fat is turned into carbs, it’s a way faster version of weight loss than just trying to burn fat by itself without utilizing any carbs.

Another piss-poor benefit of the fat burning zone is that you definitely do NOT burn nearly as many calories after your workout as you would if you were actually doing a run. This little phenomenon of intensity is called “post-exercise oxygen consumption.” If you’ve ever had a really hard sweat factory workout, and you find you’re still sweating after you’ve showered and left the gym, that means a high rate of oxygen is being used even while you’re not working out!!

Check out this sexy graph:

Judging by this, you tend to burn a hell of a lot more calories after an intense workout from fat than you probably would during the entire fat burning zone workout itself!!

So why do people gravitate towards the fat burning zone? First, people are idiots, and will do everything they are told to do by an expert (Note: Buy Muscle Imbalances Revealed today for fast relief of your muscle imbalances!!). In this case, the expert is a bloody treadmill graph that is as wrong as Jillian Michaels in a kettlebell class.

The Rack? Well, the rest of the world would know that exercise as a 1-arm clean, but hey, I guess she’s made everything else up she’s ever talked about, so why not this too??

The point of this is simple: If you want to lose weight, you have to be as energy in-efficient as possible, which means driving your body hard and fast to try to tap into some anaerobic metabolism that will burn a hell of a lot more calories per hour than a slow steady walk.

Now imagine a common goal that goes along with a weight loss goal: running a marathon. The basic premise of doing this, for those who have never tried before, is to run 42 km (26.2 miles for the friends south of the border) in as little time as possible. The first marathon most people attempt will be completed in anywhere from 4-5 hours of constant running, at an aerobic pace (Re: highly energy-efficient). Again, how are you going to lose weight by running long slow distances??? Most people who run marathons find they don’t lose weight as they are training, and some actually gain weight as their body begins to store carbs and the associated water weight as their body tries to repair the damage caused from overuse training.

Here’s an example of a client training for a marathon. Notice how hard she is working in all the sequences, and also her speed on the treadmill.

Also check out how jacked up she looks!! She started training with me about 2 years ago and has lost considerable body fat while getting redonculously fast. Her husband started training with my Boot Camp group and lost 65 pounds, with absolutely no long slow running and with only 3/4 of a knee between his two legs. We’re talking 200 step stair repeats, sprints, threshold runs, and enough sweat to make the chorus singer from “Gangster’s Paradise” jealous.

The whole point of this article is to show that you don’t lose weight by working less hard. No, no, no, it’s not quite that simple, my friends. The athletes of the world and those who are in the best “shape” get there by busting their asses regularly, working to the point of failure or near failure consistently , and then get back up and do it again 10 more times and start fresh tomorrow. Projectile vomit is not something to shy away from, but to be encouraged!! Passing out is a right of passage, much like dry heaving into a waste basket on the floor. Lungs burning? Good!! Leg’s on fire? Fantastic!! Chest feels like it’s going to explode? Outta Sight!! Left arm numb and smelling burnt toast?? Nice knowin ya!!! Hit the ER, and when you get back we can start going through some more Tabata sprints like the good old days.

Sounds pretty extreme, doesn’t it? But so is a lifetime of obesity, disease and multiple medications and limitations on your ability to live. One of my best memories was running through the Mayan jungle with Lindsay through the ancient city of Coba, and having my lungs burning as I tried to keep up with her, and successfully managing to keep up with her for the 3 kilometers from the temple to the parking lot. Challenging yourself produces the experiences we remember, where the lackluster efforts are soon forgotten. By making the most of our bodies capability to perform, we can truly see some magical instances, nonetheless being the ability to impress ourselves.