Understanding Body Mass Index (BMI)
Body Mass Index (BMI) is a height/ weight chart that can be used to give you an estimate of your ideal weight range based on your height.
If your goal is to get six pack abs or a flat stomach, you have to be near your ideal weight and, generally speaking, have a low BMI.
Body Mass Index (BMI) is a number calculated from your weight and height that roughly correlates to the percentage of your total weight that comes from fat. Generally speaking, a higher BMI is associated with higher body fat percentage.
If your BMI is high and your body fat is high, then you will not have a flat stomach or ripped six pack. Remember, ab exercises are only part of the solution if you want to have great abs.
Using BMI as a tool, you can get a better idea about how much weight you need to lose to be in your ideal range.
Here are the BMI Categories:
Underweight = <18.5
Normal weight = 18.5-24.9
Overweight = 25-29.9
Obese = BMI of 30 or greater
What is your BMI?
Calculate your BMI at this site, by simply entering your height and weight. Click to Calculate Your BMI
How did you do?
Are you in the Normal Range? Are you overweight according to the Body Mass Index scale?
If so, don't freak out yet. This is just a tool, and it has flaws.
I just calculated my BMI, and it is 25.8. I'm 5'8" and weigh 170 pounds. According to the BMI scale, I am just a little overweight, but I actually have a six pack.
The Big Limitation of BMI
BMI is a great tool and a good place to start when evaluating your weight, but the big limitation of the body mass index is that it sometimes has no correlation with body fat percentage.
While increased weight is highly associated with health problems, it is not as closely associated with health problems as increased body fat percentage.
For example, many athletes or people who are avid weight lifters may have a High BMI and be listed in the overweight category based on their height and weight, but at the same time have a 6 pack and a low body fat percentage.
Currently, my body fat percentage is 8.1% using the skin fold calipers. So although my body mass index is 25.8, I have a healthy body fat percentage and a six pack.
Body fat percentage is a more important measure than BMI, and that is the big limitation of the BMI scale.
Check out these pictures of me when I was competing as a natural bodybuilder. At the time, my body fat was less than 4%. And, believe it our not my BMI at the time was over 26 (I weighed between 173 and 175), and I was in the overweight category.
Hopefully, this simply re-emphasizes the point that there is a slight limitation to using BMI as a measure of health.
Conclusion
Even though it has a limitation, I still think it is important to measure your BMI. Generally speaking, if you want to improve the appearance of your ab muscles and stomach, then you have to lower your BMI regardless of which category you are currently in.
Take me for example, if I lost 6 pounds, my BMI would decrease from 25.8 to 24.9 and move into the normal range, and you can bet that my six pack will look even better.
Use BMI as a tool, but understand its limitation.
I like using this tool with my personal training clients, and I recommend that you use this tool. But in order to get a better idea of what your BMI means, I also recommend that you determine your Waist to Hip Ratio and your Body Fat Percentage.
Remember, in order to get six pack abs and a flat stomach you have to lower your body fat percentage through sound nutrition and consistent exercise.
So, study this site and use the tips to reach your goals.
Yours in Health,
Dr. Charles
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