Why is body composition important to weight loss?
Body composition is an important measure you can use not only to track weight loss gains, but also to determine how fat you really are. Learn why body composition is important and how you can determine what your body composition is and then use it to set weight loss goals.
What does body composition mean?
Suppose there are two women, both step onto a scale, and you see that both weigh the same amount. But for some reason one of the women is a size 18 and the other is a size 12. How can this be?
The reason for this is simple: Their body composition is different, and a scale alone does not tell the whole truth of what your body is made up of.
The size 18 woman is carrying more fat than the size 12 woman, but the two women still weigh the same amount, because fat is lighter than muscle, so you need more of it to make up the same weight as a certain amount of muscle would.
The size 12 woman has more muscle (and less fat), but because muscle is heavier than fat, she winds up weighing as much as the size 18 woman, who is carrying a lot of fat on her body.
Body composition gives an indication of two main components of your body: Body fat and muscle (lean tissue).
The more body fat you have (so the fatter you are), the less muscle you’ll have, and vice versa. And by knowing what your body composition is, you can conclude whether you’re relatively lean or relatively fat.
Body fat is measured as a percentage of your total body weight. For example, if you measure your body fat percentage and you wind up with 20%, it means that the rest of your body – 80% of it – is composed of lean tissue.
And if you know what your body weight is (in kilos or pounds), you can calculate exactly how much fat and muscle you are carrying on your body.
What body composition has to do with weight loss
Losing weight is like any other goal you set in life: It has a start, it has an end, and you need to be able to measure it to know whether you’re getting closer to the end or not. In other words, you need to be able to determine whether you’re making progress.
So the first step to lose weight is determining your start. You need to know where you are today, otherwise it will be difficult for you to set a realistic goal for how much weight you would like to lose and also how long it would take you to reach your weight loss goal.
There are 2 body components you can use to determine where you are:
- Your body weight
- Your body fat percentage
Your body weight will tell you how much you weigh, while your body fat percentage will tell you how much of what you weigh is actually body fat, and how much is actually lean tissue, e.g., muscle mass.
You can measure your body weight by stepping onto a scale, and you can measure your percent body fat by using a pair of calipers.
Once you’ve measured both, you can go on to calculate your body composition, and keep track of this during your weight loss program to know whether you’re getting leaner or not, that is, lose more body fat than muscle.
Calculating your body composition: Muscle vs. fat
Suppose you stepped onto the scale and saw that you currently weigh 151 lbs (68.5 kg). You then grabbed your calipers, took skin folds measurements off 4 locations on your body, and with a chart determined that your body fat percentage is currently 20.4%.
To summarize:
- Body weight: 151 lbs (68.5 kg)
- Body fat percentage: 20.4%
By using the measurements shown above, you can now calculate the amount of fat and muscle you are currently carrying on your body.
20.4% of 151 lbs gives 30.8 lbs (14 kg) of fat. The amount of muscle can then be calculated by subtracting the amount of fat from your body weight. This would give you 120.2 lbs (54.5 kg) of muscle.
To summarize:
- Body weight: 151 lbs (68.5 kg)
- Body fat: 30.8 (14 kg), which is equivalent to 20.4% of your body weight
- Muscle mass: 120.2 lbs (54.5 kg)
And to make sure the numbers add up, you can double-check that if you add 30.8 lbs to 120.2 lbs, you really wind up with 151 lbs.
How to improve body composition
The formula for improving body composition is simple: Eat and exercise in such a way that you increase your muscle mass and decrease your body fat.
Beware though that you need fat to survive, so while decreasing body fat is a good thing, decreasing it too much can be bad for your health.
Women should generally stay above 18 percent body fat to prevent health issues, while 10% is generally good for men.
You can increase muscle mass by training with weights and you can decrease body fat through diet and cardio exercise.
Body Composition Calculator
The following body composition calculator can be used to calculate the amount of lbs or kg of muscle mass and fat you are carrying on your body based on your body weight (in pounds or kilograms) and your body fat percentage.
Note: You must use a method to determine your body fat percentage before using this calculator.
Next step…
Your next step is to determine where you want to be, that is, determine how much you would like to weigh and at what body fat percentage.
