The Body Mass Index (BMI) and Calories Needed

About the Body Mass Index.

The Body Mass Index (or "BMI") estimates how much of your total weight is body fat. It is an artificial number, different from a straight "body fat percentage", but is generally more accurate at assessing overweight. There are limitations on the Body Mass Index's accuracy, most notably:

It will overestimate body fat in athletes and others who have a muscular build; for exceptionally muscular athletes, it is not useful at all. Such persons require sophisticated measurement techniques.
It will underestimate body fat in people over 65, becoming less and less accurate with increasing age. It will also underestimate body fat in persons with unusually low muscle mass: people with very "ectomorphic" (naturally slender, low-muscle-mass) physiques, those who have diseases causing unusually low weight (such as anorexia or many cancers), and others who have lost muscle mass.

The Body Mass Index charts given here are for adults age 19 and over. If you are under 19, see Male 2-20 BMI Index if you are male, or Female 2-20 BMI Index if you are female.

The BMI is the general standard in use today, but there are alternate ways to compute body composition. The simple Height to Weight Ratio is unexpectedly accurate, and the Waist to Hips Ratio is useful in determining risk from fat deposit patterns.

The most accurate determinations of body composition are physical.

Calculate your BMI, BMR, RMR, percent body fat, daily calories needed, daily calories used, calories used in exercise, and average daily exercise.

Personal Stats

Sex:

Male

Female

Check to use Metric system

Weight:

kilograms

Waist:

centimeters

Height:

centimeters

Age:

Weight:

pounds

Waist:

inches

Height:

Job (or Other Daily) Duties:

Exercise

Use the Worksheet*.

A)		How many days per week do you exercise?

B)		On average, how many minutes of actual exercise do you get each day you exercise?

C)		On average, what level of intensity is your exercise?

Approximate Intensity Levels:

1.7 = Relaxed - a slow walk, light gardening.

2.3 = Unstrained - golf (no cart) or walking fast.

2.7 = Moderate - low impact aerobics or doubles tennis.

3.1 = Vigorous - jogging or playing casual racquetball.

3.5 = Quite Vigorous - running 12 minute miles (7:30 kilometers), playing a singles tennis match.

4.5 = Strenuous - swimming fast laps or running 10 minute miles (6 minute kms).

5.5 = Highly Strenuous, such as running 8-9 minute miles (kms under 5 minutes) or jumping rope fast.

6.5 = Intense - running 7 minute miles (4:30 kms), cross-country skiiing faster than 8 mph (13 kph)
(Please see the Exercise List for more detailed information on intensity levels.)

D)	Do you do regular weight training?
	Occasionally or never.
	Yes, as part of my exercise routine.
	Yes, and I have gained significant muscle bulk.
	I have been a dedicated bodybuilder for more than 3 years.

* If you would like to calculate these averages automatically, or if you want your estimate to be more accurate, we have developed a powerful Exercise Averaging Worksheet. You can type in the exact type of exercise, duration, and intensity for each individual exercise; the time period can cover one day to eight weeks. It will calculate the daily averages (and even fill in this part of the form automatically). Like any software, Exercise Averging takes a few minutes to figure out — but it is a great tool if you want to know how many calories your exercise burns. It's also fun to play with. How much weight would you lose if you ran a two-hour marathon each week?'

A Little Extra Fun with Calories and Exercise.

We're thinking about a form for people who want to lose weight by exercising. We have the internet's best form to show you how many calories you will lose from a specific exercise (Exercise Form) but it might be fun to have another page, specifically for dieters, either with questions like:

"What would be some good exercises to lose 18 pounds?"

"How much weight would I lose if I started walking 2 miles in 35 minutes, 6 days per week?"

For an answer to the last question, fill in your weight in pounds here and click the little blue button: