The shape of your body is determined by three things: muscle, bone and fat. While there’s really nothing you can do about changing your bone structure, there is a whole lot you can do about muscle and fat. This ratio of muscle to fat is commonly known as your body composition.

And what is fastest way to change your body composition? Weight training. Why is it so effective? Because it builds muscle.

Muscle is key to changing your body. While fat certainly gives your body shape, muscle is what gives you shape you actually WANT!

One of greatest things about muscle is that it burns calories all day long, even when you’re lying on couch. What this means is that more muscle you have, more calories you’ll burn during day and more you’ll be able to eat without gaining weight. Sound interesting? There’s more.

Weight training stimulates your metabolism more than aerobic training such as cycling or walking. This means that you’ll continue to burn calories long AFTER you’ve completed your weight training session. The calorie-burning effect of aerobic training generally declines rapidly once you stop exercise.

Beginning trainers, who are just starting with exercise, are often under impression that they should stay away from weight training because they might gain weight before they start losing it.

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 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 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 exercise itself challenging.

2. It’s low risk - A personal trainer generally can’t go wrong by recommending low-intensity exercise to clients. Even 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 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.

Low-intensity training burns about 50% fat for energy while high-intensity training burns about 40% fat for energy. This is not a huge difference.

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 high-intensity work, you’ve just burned 14 more fat calories in half time. Starting to sound good? There’s more...

---

Low-intensity exercise only burns calories while you are actually exercising. That means 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.