BODY MASS INDEX(BMI) AND YOUR FITNESS

What Is BMI How Is BMI Calculated

I was really surprised to find out that BMI was created in the 1800's as it is only in the last couple of years that I have heard of it. All of a sudden everyone seems to be relying on BMI to tell them whether they are overweight or not and as a guide in their weight loss journey. BMI can't actually help you lose weight, it is simply a measure of your weight in relation to your height. Your BMI result will indicate whether you are in the right weight range for your height or whether you are under or over weight.

BMI is shortened for Body Mass Index. It is a tool that measures body mass and has been around for 200 years. BMI was created by Adolphe Quetelet and is sometimes referred to as the Quetelet index. Adolphe Quetelet developed the BMI formula while working on social physics and it is still used today, 200 years later, with very little variation from it's original form.

So we know that BMI measures body mass, but what does that actually mean? Well, it doesn't measure a person's body fat, but rather it compares a person's height to their weight to determine if they are in a healthy weight range for their height. It is a tool that is widely used by doctors, fitness trainers and even insurance companies to determine whether a person is overweight or obese. The BMI formula is not without it's flaws and in some cases is not 100% accurate, but it is still the preferred tool used in the medical community.

Let's take a look at the formula used to calculate a persons BMI. First you take your height in meters and square it - you times it by itself. Then you divide your weight in kilograms by the answer to your height squared. For example, if a person is 1.5 meters tall you would times 1.5 by 1.5 which will give you 2.25. If that person weights 54 kilograms you would then divide 54 by 2.25 which gives you an answer of 24 and this is your BMI.

What does that mean?

Your weight status is worked out by where it lies on the BMI chart. A normal weight range has a BMI of between 18.5 and 24.9. If your BMI is below 18.5 then this indicates that you are underweight. Likewise if your BMI is in the range of 25 to 29.9 this indicates that you are overweight. A BMI of 30 or more indicates obesity. Using our example above of a person 1.5 meters tall and weighing 54 kilograms, they fall within the normal weight range at a BMI of 24.

I mentioned earlier that BMI figures are not accurate 100% of the time and this is mainly so with people that are extremely muscular. The BMI formula doesn't distinguish between muscle and fat and because muscle is much heavier than fat then the result is not accurate. A body builder for example would have a large muscle mass and so his weight would be quite high when compared to his height. This would give him a high BMI, although in actual fact he may not have an ounce of fat on his body. For the majority of people though, BMI will give an accurate indication of whether you have a good weight for your height or not.

Next time you hear someone talking about BMI you will know exactly what they are talking about and could even tell them how it is calculated. BMI is simply a comparison of a person's weight to their height to determine whether they are in a healthy weight range.

All You Need To Know About The BMI Index

The BMI index was created in the early 1800s and is still used today to measure whether a person is in a healthy weight range. The BMI index is one of the few tools that is still used relatively unchanged 200 years after it was created. The BMI formula compares your height and weight to find out whether you are within a normal weight range or whether you are under or over weight. Although most people will know if they are putting on weight when they find their pants are getting too tight or they can see it when they look in the mirror, many doctors and also insurance companies rely on the results of BMI testing.

Insurance companies don't like to insure someone if they are high risk so they will often use a person's BMI to determine their risk. If a person is found to be overweight or obese by their BMI results then their health insurance costs can be significantly higher. Life insurance can also be higher for those who are overweight or if obese it can be refused altogether. An insurance company is protected it's own business and has the rights to refuse insurance to someone if they are high risk, however, unless other factors are taken into consideration, the BMI index is not always accurate.

To understand how the BMI is not always accurate let's take a look at how the BMI index is calculated. A person's weight is divided by their height squared - which is their height times itself. The BMI index is usually calculated using kilograms and meters, although the formula can be changed slightly to calculate using feet and pounds. For most of the population, the general BMI formula will give a fairly accurate result of what they weigh in relation to their height, but for some the result is not accurate because there are other factors involved.

What if we consider a weight lifter or a body builder, who's body is made up of a large percentage of muscle. Muscle weighs more than fat and takes up less room than fat. If someone who is solid muscle does the BMI formula then their result will indicate that they are overweight because their weight is too much for their height. However, it is because of their mass of muscle that their weight is what it is and not fat, so you can see how this result wouldn't be accurate. So if someone with a lot of muscle took the BMI test to apply for insurance, they could have higher premiums or even be refused insurance because they would be in the overweight range according to the BMI result, even though they don't have an ounce of fat on their body.

BMI results can also be inaccurate for children and also for very tall people, but generally for most average people the results will be accurate. If you calculate your BMI you can then work out what weight range you are in. A normal range BMI is between 18.5 and 24.9 so if you are within this range then you are in a healthy weight range. If you are below 18.5 then you are likely to be underweight, if you are between 25 and 29.9 then you are likely to be overweight and if you are 30 or higher then you are in the obese category.

The BMI index is a very good tool to use to check your weight range as long as you aren't in any of the categories that would make it inaccurate. When using BMI to determine your ideal weight, you will also want to use common sense and know how your body looks and how much fat you might have compared to muscle.

BMI And Body Fat And Health

BMI is one of the most popular tools that people use to determine whether they are in a healthy weight range. Because body fat and lean muscle tissue don't figure into the equation at all, many experts believe that BMI is not at all accurate for some people. In this article we will take a look at exactly what BMI is and why it isn't always accurate for some people.

BMI is short for Body Mass Index and was created by Adolphe Quetelt in the early 1800s. Basically, BMI compares a persons weight to their height and with this information will determine whether they are in the correct weight range for their height. BMI measurement has remained popular for all these years and still remains one of the most popular weight measurements.

Body fat, bone and frame size, muscle and body type are not included in the formula for working out BMI. The formula for working out BMI is to take your height in meters squared and divide your weight in kilograms by that number. Let's do an example: If you are 1.7 meters tall you would do 1.7 times 1.7 which equals 2.89. If you weigh 65 kilograms you would divide 65 by 2.89 which equals 22.49 as your BMI. This is in the normal weight range which is from 18.5 to 24.9. If you have a BMI below 18.5 then you are considered underweight and if you are over 24.9 then you are considered overweight. If your BMI is over 30 then you are considered obese.

Generally you can get an idea of whether you are in a healthy weight range by how much body fat you have and also by your general health. BMI can be a little trickier however than working out your healthy weight range using body fat.

The reason that BMI is not always accurate is because if you have a lot of muscle then your BMI might not be right. Muscles weighs a lot more than fat but will take up less space than fat so some people can have a lot of muscle but they don't look all that big. BMI doesn't take this muscle weight into account. If an athlete, football player, body builder, wrestler or anyone that gains a lot of muscle through their exercise routine, will actually calculate a BMI that puts them in the overweight or obese range.

So BMI isn't accurate for people who have a lot of weight in muscle, but what about everyone else? Well the accuracy will vary between people with different situations. Children don't get an accurate BMI and also very tall people might not get an accurate BMI either due to the weight of their longer bones. So generally, if you are extremely tall, a child or have a lot of muscle then BMI isn't a good way to measure your weight range.

The other inaccuracy with BMI is that it uses the same formula for both men and women, however women will generally carry more body fat than men so for that reason you would think the formula would be a little different to give accurate results.

East Steps For Calculating BMI

BMI is reasonably simple to calculate but before we look at that, let's take a look at BMI and what it actually is. BMI is short for Body Mass Index and this is a tool that was created in the 1800s to determine a persons weight range. The formula will give a result that will indicate whether a person is in a normal weight range for their height or whether they are over or under weight. Even though this formula was created 200 years ago, it is still widely used today.

There are some situations where BMI results won't be accurate but generally for most people it will give an accurate result. The problem with BMI is that it doesn't distinguish between fat and muscle so those people, like body builders, who have a lot of muscle, their BMI results would not be accurate. For most of us though, BMI will give us a pretty good idea of whether we are in a healthy weight range, underweight, overweight or obese.

How to Calculate BMI

There is a basic formula that is used to calculate BMI and that is weight divided by height squared - kg/m2. You take your height (in meters) and square it, so you times it by itself. Then you divide the answer into your weight (in kilograms).

Let's do an example so you can see exactly how it works. If a person is 1.7 meters tall we would times 1.7 by 1.7 which gives us an answer of 2.89. Now if that person weights 90 kilograms we then divide the weight by the height squared, so that is 90 divided by 2.89. This gives us a BMI of 31. A BMI of 31 would indicate that this person is obese.

The normal weight range is a BMI between 18.5 and 24.9. If you fall below 18.5 then you would be underweight. If you fall in the range of 25 to 29.9 then you would be considered overweight. If your BMI results was 30 or over then you are considered obese. So now you can see how the answer we got above of 31 would put that person in the obese category.

Let's do another example using the same height but a different weight. So the person is 1.7 meters and 1.7 squared is 2.89. This time let's say that they weight 68 kilograms so we divide 68 by 2.89 which gives us a BMI result of 23.5. This person would be within the normal weight range. You can use BMI calculations to determine how much weight you need to lose to be in a healthy range. With these two examples, the person in the first example would need to lose around 20 kilograms to get down to a healthy weight range.

If you don't like to work in meters and kilograms there is another formula that you can use for pounds and feet. With this formula you take your weight in pounds and times it by 4.88. Then you divide that number by your height in feet, squared. Let's work that out using a person that is 200 pounds and 6 feet tall. You would times 200 by 4.88 which is 976. Then you would take the height in feet and times it by itself, so 6 times 6 equals 36. Now take the weight answer of 976 and divide it by 36 which equals 27.1 - this is your BMI. A result of 27.1 would put a person in the overweight range.

When calculating your BMI just remember to factor in whether you have a lot of muscle or not as this can make the results inaccurate.