What do most of us want?

To lose a little weight and tone up.

What that really means is we want a reduction in body fat percentage.  After all, “toning up” is really just skimming a little fat off the top of the muscles that already dwell beneath.

And what is the most effective way to reduce body fat?

Burn more calories than you eat.

Sure, you can calorie-restrict.  Or, you can do lots of cardio.  If you’re really good, you can do both, and sure enough, calorie-by-calorie, you will lose body fat.

But I’m more interested in being time-efficient. And that’s where EPOC–excess post-exercise oxygen consumption–comes in.

In order to maximize the amount of calories burned in a workout, you must maximize the amount of oxygen used during activity.  In other words, the harder you’re breathing, the more calories you are burning.

But there’s more to it.

By maximizing the amount of oxygen you use during the day–and not merely in your workouts–you can burn more calories.  After your workout, your body needs to use more oxygen to replenish energy supplies, lower tissue temperature, and return the body to a resting state.  The harder you work out, the longer it takes to perform these tasks, the more oxygen your body utilizes, the more calories you burn post-exercise.

When people say, “You’re metabolism runs higher after you work out,” they are really referring to this EPOC principle.

The higher the intensity of exercise (the more calories you burn during exercise), the higher the magnitude of EPOC (the more calories you will burn after exercise).  Double-whammy.

It’s like taking your car out for a drive.  If you drive it hard, red-lining occasionally–burning more gas–and then park it back in the garage, your car will take much longer to cool down its engine (more EPOC).  If you simply take it for an easy Sunday drive–being fuel efficient–it will take less time (less EPOC) to cool.

In the goal of body fat reduction, the key is to burn calories, rather than focus on burning fat.  Long bouts of cardio are a nice way to improve cardiovascular fitness, but they aren’t the most efficient use of time at the gym, and they certainly don’t contribute as much to high EPOC as other types of training.

And what happens after long bouts of cardio?  You deplete glycogen stores.  If you’re a cardio-holic, you may have a tendency to always be running on empty, and that paves to way to a binge on carbohydrates later, as your body begs for repleted glycogen.  This makes for fit-fat people.

The after-burn of EPOC should not be underestimated.  Swap out your 40 minutes of steady state cardio for 20 minutes of work on the bubble between aerobic and anaerobic work, and enjoy the after-burn.  Eat immediately after your workout (preferable a source of easily digestible carbohydrates and some protein) within 30 minutes of working out in order to give your body the building blocks it needs to replete glycogen stores and repair muscle tissue, while offsetting a binge later.  This, in effect, will lead to more sustainable weight loss.

Less time at the gym; more bang for your buck.  More time for other things: like recovery.