The Aerobic Fallacy

For all of you spending countless hours on the treadmill doing steady state cardio, I have found a great article for you to read. This article by Kyle Newell published on EliteFTS.com does a great job discussing why aerobic training is not the best type of training when looking to lose fat mass.
Read on:

I believe that it’s part of my job as a fitness expert to bring the science to you. Much of what is currently out there is based on nothing but tradition and acceptance. You can do what you want with the information I’m going to present, but all I ask is that you at least give it some thought.
This may come as a shock to you, but to sculpt a lean, muscular, athletic, and toned body, aerobic exercise is one of the worst ways to achieve this desired look. Aerobics means “with oxygen” and in terms of exercise, much of what is seen in the gym on the “cardio” equipment is aerobic. The reason I’m quoting “cardio” is because cardio is not the same thing as aerobics, yet the two are used interchangeably every day.

All aerobic exercise is cardiovascular in nature, but not all cardiovascular exercise is aerobic. Cardio simply means any mode of exercise that stresses the cardiovascular system so weight training is cardio too. Some other forms of aerobic athletics include bicycling and marathons.
Before I get into the science of this topic, just realize that aerobics did not become hugely popular until the late 70s/early 80s. The studies that were coming out regarding the benefits of aerobic exercise were funded and put out to the public by the companies that were making the “cardio” equipment to put in all of the gyms going up around the country. Think about the timing of everything. Gyms did not start to become popular until this time when fitness was brought to the mainstream by none other than one of my heroes, Arnold Schwarzenegger. Hmm, so all of a sudden when gyms started exploding in this country, aerobics became great for us, and studies just “happened” to coincide with this time period? I have no problem with aerobics if the person truly enjoys it. It can be a very stimulating experience. My problem is with the misapplication of aerobics to sculpt the lean physique that so many of us are after.

For those of you who have seen Pumping Iron, notice that Arnold was in the best shape of his career, yet he performs no aerobics, just intense weight training and dieting. When Arnold made his comeback to the bodybuilding stage in 1980, he had bought into the aerobics revolution also, and the physique he brought to the stage was the smallest, softest, and out of shape of his entire career.

Aerobics train the nervous system and musculature system to become slow. It stresses our type I muscle fibers (slow twitch and red ones—remember this for later on). These are not the fibers that we want to stress if our goal is to gain some muscle and lose body fat. Those fibers are the type II fibers (fast twitch and white). So already you can see that if you’re performing intense resistance training and hours a week of aerobics, you’re stressing two different systems, which is not a good thing.

Let’s examine the chicken and the duck. Now, you know that dark meat has a lot more fat than white meat. The chicken is predominantly white meat, and the duck is predominantly dark meat. Myoglobin, which carries oxygen molecules to the muscle for work, is what makes the meat dark. The duck can fly for thousands of miles while the chicken can’t even get off the ground for more than a few seconds. Yet, the chicken is much more muscular and lean. Ducks are aerobic, and they store fat for very effective use.

Aerobics trains the body to become very efficient at using fat and storing fat because the predominant fuel source in aerobic exercise is fat. Did you ever hear of the “fat burning zone?” Throw it out the window. It is quite possibly one of the most misleading pieces of fitness information ever! If your car is more efficient at using fuel, is it going to use more or less of it? The correct answer is less of it, which is great for your wallet but not your body if we’re talking about efficiency of fat use for exercise. We want the hummer engine, the big gas-guzzler, the most fuel inefficient car we can find to burn body fat.

To equate this to exercise, we want high intensity exercise with rest interspersed. We want a very large oxygen deficit. In a study by Tremblay and colleagues, it was demonstrated that high intensity exercise, specifically intermittent, supra-maximal exercise, is the most optimal for fat loss. There were two groups—the long, slow distance aerobic endurance group (LSD) that was on their program for 20 weeks and the high intensity interval training (HIIT) group that was on a program for 15 weeks. The amount of energy utilized (calories) by the LSD group was DOUBLE that of the HIIT group. However, six skin fold measurements demonstrated greater loss in the HIIT group than the LSD group. When this was expressed on a per energy basis, the HIIT group’s reduction in skin folds was nine times greater than the LSD group. That is what you call more bang for your buck (Willey 2007).

The HIIT group created large post-exercise oxygen consumptions (EPOC), which can take up to 48 hours for your body to fully recover from. This is where fat loss occurs, not during the hours spent on the treadmill. In another published study by R. Bahr and performed at the Department of Physiology at the National Institute of Occupational Health in Oslo, Norway, it was demonstrated that low intensity (defined as 65 percent of maximum heart rate for less than one hour) led to a total EPOC of only five calories. On the other hand, intensive exercise where the heart rate was above 85 percent of the maximum, led to EPOC values of up to 180 calories (Staley 2005).

As I have said in the past, the body is incredibly adaptive. What used to take 30 minutes on the cardio equipment to burn 300 calories will soon take 40 minutes, then 45, and then 50. What you are doing is creating the body to be a fat storing, super efficient, fat burning machine! Think about it. Do all those people at the gym who slave on those machines ever seem to change? Maybe when they first start, but it has been shown that with this type of exercise, the body becomes almost completely adapted after the first eight weeks. Go to any 5K, marathon, or bike race and 60–70 percent of the people who cross the finish line are fat.

If the body is more efficient at burning and storing fat, this will also equate to a lowered metabolism, which, again, is not a good thing. We are looking for exercise that takes the body hours to recover from (large EPOC). You will not even be aware of this recovery, but if you were put in a lab, oxygen debt would still be elevated for a few hours to 48 hours! Did you ever notice that even after running a few miles, you could hold a conversation during it or immediately following it? The human body recovers very quickly from aerobic exercise. This is not optimal for fat loss.

For those of you aerobic athletes, there was another study done by Tabata in Japan that showed anaerobic interval training actually caused greater increases in AEROBIC capacity, more so than the group that actually performed aerobic running! That is just a piece of information to use when you want to switch up your training and do some shorter duration type of stuff.

Which is leaner and more muscular—the marathon runner or sprinter?

Sprinters such as Ben Johnson of Olympic infamy were known to go to McDonalds and see how many Big Macs they could eat, often downing 5–6 without a problem and staying shredded. These athletes have created those big gas-guzzling machines that I was talking about earlier. Look at gymnasts. They never do aerobics, yet it can be argued that they have the best physiques of any group of athletes out there. Their training consists of explosive high intensity bouts of exercise often with nothing more than their body weight.

In a different capacity, aerobic athletes, most notably marathon runners, are the most injured group of athletes in the world. Every time the foot strikes the ground, 3–5 times the body weight is applied in force up through the skeletal system. Ouch! The stress hormone cortisol is also produced in very large amounts when the body is constantly performing aerobics. Despite what you see on those silly commercials, cortisol is essential to the human body. However, high amounts will cause the accumulation of body fat, most visibly around the mid-section. High cortisol will also negatively impact your adrenal glands over time. Distance runners who train upward of 100 miles per week do not expend more than 800–1300 “extra” calories each day above their normal energy requirements (McArdle 2001). Does that sound like it was worth their time investment?

How do you make sure your exercise is intense enough? If you can hold a conversation once a set or interval is completed, you are more than ready to go again. Remember, you are trying to create a deficit. What about the really heavy person who lost massive amounts of weight from their aerobics program? They would have lost weight doing any form of activity that took them out of their sedentary state. The composition of weight lost also needs to be looked at. If you are just performing cardio, your precious muscle is being used as a fuel source, thus it is completely common for people to lose tons of weight yet be a fatter, smaller version of their former self. This will happen because the composition of weight lost will come from muscle and fat, not predominantly fat.

I know that many of you will be resistant to this idea, and this concept may not even catch on in my lifetime. However, I did enjoy making you aware of this information! If you like to run and jog and ride bikes, great. Go for it. I’m all for it. As I said before, I am. Activity is awesome, any kind. Just realize what benefits you are trying to get from it. I have been studying and trying systems of resistance training that allow me to get as “shredded” as I need to without stepping foot on any more cardio equipment.

Kyle Newell is a strength and conditioning specialist (CSCS) located in New Jersey. He is a physical education teacher and high school strength and conditioning coach at South Brunswick High School in New Jersey. He specializes in body transformation and sport specific conditioning and is pursuing his master’s degree in exercise science through the University of Texas Pan American. He is also a competitive bodybuilder in addition to being a certified sports nutritionist (CISSN). Kyle is available for online consulting. Just remember that proximity has nothing to do with expertise. He can be reached through his website at http://www.bodyperformancecoach.com.
source: http://www.elitefts.com/documents/aerobic_fallacy.htm