Aerobics and Weight Loss: Why Running Sucks for Weight Loss!

  One of the first questions we are asked by clients looking to lose weight is; where are the treadmills, stationary bicycles and ellipticals? The other, equally common question is about the type of aerobic classes offered and how often they are and how many can I sign up for?

As a gym owner, and personal trainer I am unfortunately very much aware of the importance of aerobics in the scheme of getting people to sign up for training and programs, but the irony remains that aerobic exercise is vastly overrated as a means of getting into shape in terms of losing weight and keeping it off.

The facts are that currently 80% of people are using aerobics as a tool for trying to lose significant amounts of body fat. This is primarily driven by advertising and misinformation, unfortunately not results. In this article 

I want to highlight the common misconceptions that masquerade as good training practices and show the overall superiority of resistance exercise over aerobics in terms of reducing overall body fat.

Both men and women everywhere will look to the well-defined midsections of so many fitness magazine cover models and with absolute certainty, I can say that if taking a spin class and doing cardio was the way to attain it, that almost everyone in your neighbourhood gym would look just like the models you see on TV, and they don't.

  It can be extremely frustrating, having read the books, and put in the time attending class after class, and riding, stepping or jogging the life out of yourself and still not have 'the look.' Sadly the fault does not lie in you, the individual, but rather in a lack of credible information from authorities that are not simply vested in selling you something. The definition of insane is doing the same thing over and over and expecting a different result! So, as I said in the last article about over training more is NOT better!

Scientific studies abound in the media about the wonders of aerobics for fat loss, and the ever present argument about its heart healthy benefits. Many of these claims are being refuted by more credible experts in the exercise field. But it still somehow does not stop thousands people from being frustrated over their failure to transform their bodies after working so hard to do so.  

Firstly, let us define the term aerobic. Since it is often misunderstood to begin with the word aerobic means; ‘with oxygen’ and it refers to a specific metabolic pathway within the body that yields energy through the oxidation of fats and carbohydrates.

  When most people think of aerobic activity they think of long duration, low intensity exercises that elevate the heart rate, e.g., jogging, spinning classes, stair climbing, rowing etc. (Note however that these actions of the heart and lungs are completely dependent on muscular activity). The theory is that by performing  aerobic activity your body will burn fat as an energy source, increase your resting metabolic rate (metabolic rate being the amount of  calories that your body uses), and thus burn off unwanted extra calories. It is also believed that aerobic exercise will create an increase in endurance and provide a protective benefit from heart disease. This all sounds great in theory but the reality outside of the lab is quite different.

While I will agree that there are some benefits to the cardiovascular system from these exercises, the fact remains that numerous studies prove conclusively that you can achieve a significant cardiovascular effect through the some high intensity weight training and sometimes to a greater extent!

  Aerobic exercise does not burn a large amount of calories, sadly this is nothing but a myth, and though it may stand as accepted fact for most in the field it does nothing to change the physiologic reality that refutes it. 

Here is an example:

A 180 lb man supposedly burns 850 calories during an hour of an all-out high intensity aerobic class, and that same individual would barely burn 900 calories after running at a 9 minute mile pace for an hour without stopping! (A female of a lesser body-weight would burn even less calories.)

So these might sound like a lot of calories but consider that to lose one pound of fat you need to burn a total of 3,500 calories! In fact one pound of fat can hold enough energy for over 10 hours of continuous activity! 

  Our fat storage system is a biological fail safe that we as human beings have acquired as a means of allowing us to survive periods of drought, famine and overall lack of food for the first several hundred thousand years of our existence. Taking this evolutionary reality into consideration, it makes sense that our bodies would not shed its fat stores easily from something as much of our early ancestors' everyday life as running or walking. If this were the case and losing fat was that easy, we would never have survived as a species.

  The idea of increasing your metabolic rate from aerobic is simply ridiculous. If aerobic exercises do not burn a significant amount of calories while you are doing them, do you really think that they would make you burn a significant amount when you stopped doing them? Study after study have been done to show that aerobics do not have a significant long term effect of increasing metabolism; in fact some researchers found that such regular exercise actually lowered metabolic rates in some participants! That’s right, it lowered your metabolism! Mostly due again to high levels of stress hormones and the low intensity of the exercise itself!

In other studies it was shown that endurance athletes report having to eat LESS to maintain their ideal weight as their training duration increases. It seems that their metabolic rate slows to conserve calories as a defense mechanism, similar to the way metabolism slows in those with a low food supply as a defense against starvation. Slower metabolism means that you are much less likely to lose body fat. Exactly the opposite of what you want to do.

  An interesting study conducted at the University of New South Wales, Australia found that after 15 weeks of high intensity workouts three times a week, women in the high intensity group lost an average of 5 ½ pounds of body fat. This figure correlated with an 11.2 % decrease in their overall body fat levels. The other group that did three conventional steady state cardiovascular workouts (ran 10-12km) per week for the same period of time actually saw an increase in their overall body fat levels!

  Consider also the physiques of endurance athletes such as marathon runners. The marathon runner may look skinny, but does not exactly have the taut and toned muscular physique that you would expect. Actually they’re a bit on the flabby side, and this makes sense biologically for an endurance athlete. If you regularly perform a long term repetitive activity that requires fat as a fuel source, your body will make fat storage a priority, and will also shed any excess muscle not directly involved in the activity.

The end result is that most endurance athletes will have lower muscle mass, and higher body fat due to the nature of their exercise. Exactly the opposite of what people trying to get into shape are looking to achieve

  Not only are most so called aerobic activities inefficient with regards to fat loss, they can also be very dangerous. I have had so many clients over the years with severe injuries to their knees, hips, hamstrings, ankles and backs from running, stair climbing and aerobics classes. Even seemingly benign activities like stationery cycling can generate a great deal of wear and tear on your joints. Over a period of time you can seriously injure yourself from what are termed overuse injuries. You may feel fine now, but the damage is cumulative, building up over the years until it finally impairs your mobility.  Arthritis, tendonitis, tendonosis and bursitis are much more prevalent in endurance athletes than in their weight training counterparts!

So I don’t want to say that you shouldn’t run, bike, row, and do spinning classes. They have their uses and can be fun to break up the monotony of weight training, but if your goal is to lose fat and look chiseled then they should not be the focus of your training program! Remember also that nutrition plays a key role in physique augmentation!  Don’t neglect your body and feed it right!

PJM