By Sean Barker
Author of The Dad Fitness System
| I hear this question often in regards to cardio and burning body fat. “Should I perform cardiovascular exercise for a longer duration at a low intensity 45-60 minutes, or shorter at a higher intensity, 15-20 minutes? |
Research shows that the human body uses mostly fat during the duration of low intensity exercise. So people automatically thought that the longer they exercised the more fat that they would burn.
But what the people failed to realize was that the amount of calories burned after an exercise session is far more important than the calories burned during the exercise itself. Low intensity exercise does not challenge the respiratory systems within the body; therefore this form of exercise does not elevate the metabolism nearly as much as exercise performed at a higher intensity.
When aerobic exercise is performed at a higher intensity, the respiratory system and glycogen stores are challenged which in turn elevates the resting metabolism for the hours after exercise. Which means more calories are burnt even at rest.
The secret to this exercise methods extreme effectiveness is the ability to increase your body’s metabolism far beyond its normal state. More specifically it is referred to as E.P.O.C. otherwise known as “excess postexercise oxygen consumption.” EPOC represents the process your body goes through in which energy is used to recover from exercise.
When you finish exercising, it takes time and energy for your muscle cells to return to resting levels. Energy is also needed to replenish depleted glucose, protein and fat stores, and to remove accumulated cell waste. The more rebuilding that needs to be done, the greater the rate of EPOC, which in turn, means more calories from your body’s fat stores are being burned after your workout. While the primary factor in determining EPOC is exercise intensity, there is also duration to consider — just not to the same extent.
A good analogy I like to use to describe this effect is visualize spinning one of those Tops that you used to spin as a kid. Spinning the top with your hand real hard is similar to high intensity exercise. But when you let go of the top the momentum continues to spin the top on it's own. Your metabolism works in the same way. After high intensity intervals, you create "metabolic momentum" which continues to spin really hard on it's own, even hours after exercise.
Studies show your metabolism remains elevated to such a level up to 48 hours after high intensity exercise. When you perform exercises like sprints or bodyweight circuits, you will see how EPOC works to literally melt the fat off your body!+
Not too long ago, the exercise industry preached the concept that lower intensity aerobic exercise burns more fat than high-intensity exercise. Although this is still true, nowadays the approach has somewhat changed.
When you exercise at a high intensity, much of the fuel your body burns comes from carbohydrates, because they are more easily accessible than fat. But the energy requirements of recovery, especially an active recovery, need to be considered as well. EPOC primarily depends on fat and lactic acid (a waste product produced by your muscles) as fuel. In fact, the recovery from EPOC burns mostly fat, so intense exercise is associated with a significant amount of fat breakdown.
Always remember, losing body fat is all about calories in and calories out. So for the most efficient way to get the calories out on a consistent basis, perform higher intensity cardio to burn more fat in less time...
John signs up for the Sectionals. He never even played sports in school. He has never done any form of competition before. He has become so strong mentally and physically that he is able to take this challenge on without thinking twice about it. Well....... maybe he thought at least once about it.
Bess signed up for the Steamboat Marathon. She's never done a marathon before. And she is training CrossFit Endurance style, for 5 weeks, to see how she performs. Last weekend she "dropped a knee" (as she called it - it must be a telemark skiing term) for 6 hours straight after not skiing for most of the winter.
Peter is back on his road bike after back surgery sidelined him for months. He rode for hours this weekend and it was pure joy, and effortless. He has turned his son on to CrossFit so that they can climb Denali next summer.
Kay is a road bike racer for a team in Golden. She said her last training ride up Lookout Mt. seemed easy. Who says that?! She is doing CrossFit to increase her endurance and power. It appears to be working.
Lida is off to Moab to do a half marathon. Oh, and this is in between snowshoeing, biking, swimming, skiing and training for an Ironman.
Tony comes in today with a bumper plate stand that he welded himself. He took it upon himself to make it so that we would no longer have to stuff the bumper plates in a wooden crate. That is so cool. And generous.
Eric came to us because the generic box gyms have left him bored, depressed and dissolutioned. Where is the passion he once had? Well, he found it again. Here, and with CrossFit. So he brings along his girlfriend and his Mom and now we are working on his Mom's fiance and best friend..............:)
This is what CrossFit is all about. And this is just a taste of what the people at Foothills CrossFit are all about. LOVE IT !!!!!!!!
