Wrong.
After reading this article, I guarantee you'll develop a new respect for high-intensity cardio training for fat loss.
Low-intensity exercise is defined as working at a heart rate of about 60% to 65% of your maximum heart rate (which is equal to 220 - your age = maximum heart rate, thus if you are 20 years old, 220 - 20 = 200 max HR). High-intensity exercise is defined as working at about 75 to 85% or more of your maximum heart rate.
Using the previous example for maximum heart rate (max HR=200), working at 60% of your max HR would be 120 beats per minute and 80% of that would be 160 beats per minute.
There are several reasons low-intensity exercise is normally recommended for fat loss.
1. It's easy - In many cases people who are trying to lose fat don't always feel energetic enough to do hard training due to the caloric deficit (a.k.a. diet) that they are on. In these cases, just sticking to an exercise program can be hard enough, never mind making the exercise itself challenging.
2. It's low risk - A personal trainer generally can't go wrong by recommending low-intensity exercise to clients. Even the most out of shape person can usually do low-intensity cardio training safely. While this is certainly appropriate advice for novice trainers, it does not necessarily apply to the more experienced trainer when it comes to effective training.
3. It burns a higher percentage of calories from fat - this is very true: exercising at a lower intensity does burn a higher percentage of calories from fat than high-intensity exercise. But, as I will explain, this does not necessarily mean you're going to burn more fat.
Let's crunch some numbers to show you exactly what I mean when I say high-intensity exercise burns more fat.
Say, for example, walking for 20 minutes burns 100 calories. Then 50% of 100 calories is 50 fat-calories burned.
Now say 10 minutes of interval training at a high intensity burns 160 calories. Well, 40% of 160 calories is 64 fat-calories burned.
By doing the high-intensity work, you've just burned 14 more fat calories in half the time. Starting to sound good? There's more...
Low-intensity exercise only burns calories while you are actually exercising. That means the moment you stop exercising, your caloric expenditure goes back down to nearly baseline levels. Within minutes, you're not burning many more calories than if you hadn't done anything at all.
High-intensity exercise, on the other hand, continues to boost your metabolism long after you're done (often up to 24 hours after, depending on the length and intensity of the training session). This means you're continuing to burn many more calories all day long!
Low-intensity exercise does nothing to build or support muscle mass. Maintaining muscle mass is critical to an effective fat-loss strategy as muscle burns fat just sitting there. Want to keep your metabolism working to burn fat? Do whatever you can to build or keep your muscle tissue.
High-intensity exercise has the potential to increase muscle mass. Compare the body of a top sprinter to a top marathon runner. The sprinter carries far more muscle mass. You won't get big bulky muscles from high intensity training but you will get shapely and more defined muscles!
How To Do It
Now that you've seen how effective high intensity training can be for fat loss, how is it done?
The absolute easiest way to start this type of training is to get on a cardio machine at the gym and select the interval training program. As you'll see, you'll start off with a fairly light warm-up cycle, then quickly jump up to a high intensity level for a short burst. You will then drop back down to a low level for a period of time, then back up to a high level again, repeated several times and finishing with an appropriate cool-down period.
The repetition of these intervals is the nuts and bolts of high intensity interval training. You can also do it manually by adjusting your intensity level up and down over short periods of time.
For example, do 30 seconds at high power then 30 seconds at low power. Repeat. It's very simple and very effective.
Another excellent method for doing high-intensity training is called aerobic interval training. It is essentially the same concept as the previously explained interval training but the work intervals are longer with the intensity level somewhat lower. A good example would be running at a pace that you can only keep up for about 5 minutes then walking for 2 minutes then running 5 more minutes, walking 2 minutes, etc.
High-intensity training can be applied to any form of cardiovascular exercise. Anything from walking/sprinting to swimming to bike riding will work perfectly. I would recommend doing his type of training 2 to 3 times per week for best results. As always, be sure to consult with your physician before starting any exercise program.
Remember, what you get out of exercise is directly proportional to what you put in. Work at high-intensity training for awhile and see just how much better your fat-loss efforts go.
Courtesy by: Nick Nilsson
