2. Cardio Until You Crawl

By | February 12, 2004

Don’t put too much emphasis on cardio. For some reason, aerobic exercise continues to be pushed as the end-all and be-all answer for fat loss.

It does not take much common sense, however, to look around and realize this may not be the case. Consider the number of overweight aerobics instructors you see in the gym. Evaluate the information available that female aerobic instructors are more apt to seek liposuction than any other group except actresses.

When we look at marathon runners, we see they are lean … but so are sprinters, and I don’t know many sprinters who spend hours at a time on treadmills or recumbent bicycles.

Excess cardio work, a huge stumbling block for fat loss has a basis in an argument that sounds entirely logical. Let’s do a little Energy Systems 101 so we can better understand why this myth is so prevalent, and figure out what to do to dispel it.

First, your body has something called energy systems that are used to fuel activity. Contrary to what some people may believe, your body draws on all of these systems, all of the time. The activity you perform, however, dictates which system is the one mainly being used (not exclusively). Just as your body always gets some of its energy requirements from protein, your body is always using a little bit of each system.

Two systems are anaerobic, which means they do not use oxygen. The ATP-CP system is used for short, intense bouts of work. Without getting too technical, a molecule in your muscle cell is split to generate energy, and creatine phosphate is used to rebuild that molecule so more energy can be produced. This system is especially important for high intensity activity such as weight training, but it only lasts for around ten seconds. Creatine supplementation can increase the capacity of this system.

The second anaerobic system is known as the lactic acid system or anaerobic glycolysis. This system is the predominant system for moderately intense activity that lasts around 2 minutes. This system uses glucose (a form of sugar) present in your blood, or glycogen stored in your muscle cell, for fuel. Post workout nutrition, such as shakes, may help recharge this energy system and keep you primed for the next workout.

The final system, and the one that takes center stage with aerobic activity, is the oxidative system because, yes, it uses oxygen. This system can use protein, carbohydrate, or fat for fuel, but relies mainly on carbohydrates. What is interesting about this system is that, depending on your heart rate; it will use more or less carbohydrate, protein, or fat. The lower your heart rate, in general, the more it will use fat for fuel rather than carbohydrate or protein.

This is where science stops and pure speculation can ruin the whole affair. First, people get excited when they realize that the lower heart rate burns more fat. If you think about it, sitting at your desk or sleeping makes you a fat burning machine! While this is, to a certain extent true, if you focus too closely on the details, you’ll lose the big picture. What is most important for fat loss is total calories, period and point blank. The type of activity you perform, the nutrition you use, and even supplementation, will all affect this, but without the right calorie balance, you will simply not have a net loss in fat.

Choosing a system that uses more energy from fat doesn’t necessarily burn more fat. To illustrate: let’s say you are sitting at your desk for a few hours. You may burn, say, 80 calories and maybe 80% of those calories are from fat. (These are arbitrary numbers to illustrate a point — you just burned 80 total calories and about 64 of those were from fat.)

Now if you get on the treadmill and run on an incline for 1.3 miles in 10 minutes. You probably burned 200 – 300 calories in 10 minutes. You may have only used 50% or even fewer calories from fat, but in those 10 minutes on the treadmill, you still burned more fat than in 2 hours of sitting at your desk! So, you can burn a high percentage of calories from fat but a lower number of total calories, or you can burn a lower percentage of calories from fat but a higher number of calories.

The fact is, zeroing in on cardio is oversimplifying and setting you up for failure. Incorporate some cardio. It is great for your heart. It helps to burn calories and will contribute to fat loss. But nutrition is just as important — you will have to stay on the treadmill for a long, long time to make up for one super-sized value meal at a fast food restaurant.

Resistance training not only burns a ton of calories when done intensely, but it can actually raise your metabolism so that you can burn additional calories even after you are finished exercising! Not only that, it stimulates muscle growth. Muscle tissue burns additional calories and contributes to your ability to drop fat.

An interesting fact about gaining muscle is that more muscle tissue means more enzymes and small cellular structures called organelles that are used to burn fat.

Muscle tissue gives your body more materials used in the processing of fat for energy. Hence, its contribution to helping you lose fat goes beyond just burning extra calories. This is why a program that balances proper nutrition with cardio and resistance training is key to maximize fat loss.

See also: Maximum Cardio

I tried to avoid citing specific studies for this article, but a few key examples may help drive home the point.

Weight training combined with diet burns more fat than weight training by itself or diet by itself. (1)

Weight training combined with cardio burns more fat than cardio by itself. (2)

So the best combination appears to be all three! And don’t get caught up in that more-is-better mentality, either. Save the extra cardio and exercise for when you are closer to your goal. Add too much, too soon, and you will simply burn out with nothing more to give.

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