The Full Time Worker's Guide to a Good Physique

The Full Time Worker's Guide to a Good Physique
How to keep fit despite a hectic lifestyle.

Dom Thorpe

Dom Thorpe
Managing Director and Principal Trainer

Wednesday 8 June 2011

Body Mass Index Simplified

Our body mass index is a way to compare our weight to our height. The theory is that there is a “healthy” weight target range for any given height. It is worked out by dividing our weight by our height squared. The government suggests that a healthy BMI should be somewhere ranging from 18.5 up to 24.9. Below 18.5 and we are considered underweight, above 24.9 and we are considered overweight. If our BMI is 30 or higher we are considered obese. Below are my current measurements applied to the BMI formula to show you how we calculate it:

BMI = MASS (KG) / HEIGHT x HEIGHT (METRES)

My BMI = 79KG / 1.85 x 1.85

My BMI = 79 / 3.42

My BMI = 23.1

Good news for me! I’m within the “healthy” range. But do I need to keep performing this calculation every time I want to check when my weight changes? When will I know if I’m overweight? What if I forget how the equation works? What if I can’t remember what the “healthy” zone is? All good questions which is why I’ve created the table below to simplify the whole process by eliminating the BMI from the equation and tell me my maximum and minimum weights if I want to remain “healthy”. All you need to do is remember your maximum and minimum “healthy” weights. Find your height and cast your eyes across the table to see what your recommended range is.

Height

LBS (lower limit)

LBS (upper limit)

Stone (lower limit)

Stone (upper limit)

5’0”

94

127

6st 10lbs

9st 1lbs

5’1”

98

132

7st

9st 6lbs

5’2”

101

135

7st 3 lbs

9st 9lbs

5’3”

104

141

7st 7 lbs

10st

5’4”

108

146

7st 10lbs

10st 6lbs

5’5”

111

149

7st 13lbs

10st 10 lbs

5’6”

115

155

8st 3lbs

11st 1lbs

5’7”

118

159

8st 6lbs

11st 5lbs

5’8”

122

164

8st 10lbs

11st 10lbs

5’9”

125

168

8st 13lbs

12st

5’10”

129

174

9st 3lbs

12st 6lbs

5’11”

132

178

9st 6lbs

12st 10lbs

6’0”

137

184

9st 11lbs

13st 2lbs

6’1”

140

188

10st

13st 7lbs

6’2”

143

192

10st 3lbs

13st 10lbs

6’3”

147

198

10st 7lbs

14st 12lbs

6’4”

152

204

10st 12lbs

14st 8lbs

6’5”

157

211

11st 3lbs

15st 1lbs

By using the above table we can use our height as a reference to gain an idea of what our maximum or minimum weight should be without the need to perform any equations. Bear in mind that the closer you are to the upper figure, the closer you are to being overweight and vice versa for the lower limit. Ideally we should be somewhere in the middle of those figures.

There are exceptions to this rule and many people have been incorrectly classed as overweight or even obese due to large amounts of muscle mass. If we look at an extreme example like Arnold Schwarzenegger in his top form he would weigh in at 235lbs and at a height of 6 feet 2 inches or 30.2 on the BMI scale-so technically obese but he clearly wasn’t overweight in the sense that we use the term. Having said that, we could debate over whether or not he was in a state of good health given the amount of strain put on his heart which would have had to work overtime in order to fuel those huge slabs of meat.

So to clarify, the BMI scale is only really an effective way to gauge weight for inactive individuals. However if you can remember your boundary weights and try to stick within them you should be at lower risk of bad health than you would be otherwise.