Sunday, 27 July 2008
Elendil's Fitness Plan: Step 2 - Measuring Results
The first step in our series was to commit to a healthy lifestyle. An attitude that I am going to do this come hell or high water. The second step on the journey is to consider how we plan on measuring our results. We need good metrics to track our bodies progress as we start living healthy.
The preferred measuring tool for most people is the scale. I understand the popularity of it. It seems a reasonable measure and it is easy to use. Unfortunately, weight is it isn't the best indicator of health. Why? The best way to illustrate the problem is to use an example.
Picture in your mind Joe Six Pack. He is 6'1"" and weighs 250 pounds and leads a sedentary life style. What do you think he looks like? I am guessing you are picturing a guy who is clearly over weight will a beer belly. Now picture in your mind Ray Lewis, the Pro Bowl Linebacker for the Baltimore Ravens. I am guessing you are picturing a guy who is ripped and is waiting to remove your head from your shoulders. He too is 6'1" and weighs 250 pounds. They weigh the exact same. Yet who do you think is healthier?
OK, so weight can be a bit misleading. What would be a better method? Measuring a person's body fat percentage. Body fat percentage is your fat weight divided by your total weight. Joe Six Pack from earlier is probably over 30% body fat. Raw Lewis on the other hand has around 7% body fat. It is now obvious which person is in better shape.
How do I measure body fat and what should my body fat percentage be?
Measuring body fat is generally not as easy as stepping on a scale, but there are several ways to do it. The best way to do it is to use hydrostatic or underwater weighing. It is accurate but tends to be expensive and not something you can do every few weeks.
Another good method is to use skinfold calipers. They are an inexpensive tool for measuring body fat. It makes spot measurements in various places on the body and from those measurements determines a body percentage result.
Another method that is easier to use and doesn't require any special equipment is the US Navy Circumference Method. It is a simple tool developed by the military to accurately determine body fat percentage in adults. It appears to be as accurate as the skin fold test and easier to do. I also prefer it because it is easier to make consistent measurements with a tape measurer than calipers.
All that is necessary to determine body fat percent is a your height, weight, neck and waist measurements. Women need an additional hip measurement. The results are plugged into a formula and out spits the results.
For men the formula is
%Fat=495/(1.0324-0.19077(log(waist-neck))+0.15456(log(height)))-450
For women the formula is
%Fat=495/(1.29579-0.35004(log(waist+hip-neck))+0.22100(log(height)))-450
If you don't want to calculate the results by hand, a number of sites provide calculators for the equations.
Now that we know how to calculate it, where does our body fat need to be? For men and women ideal body percentages are different. Below is a chart describing ranges of body fat.
| Women | Men | |
| Essential fat | 2–15% | 2–5% |
| Athletes | 16–20% | 6–13% |
| Fitness | 21–24% | 14–17% |
| Acceptable | 25–31% | 18–25% |
| Obese | 32% + | 25% + |
Looking at the chart we can see that Joe Six Pack from our earlier example is clearly obese while Ray Lewis is a top athlete. A result which more accurately reflects our initial images of these two people. In my opinion to live a healthy life style you need to be in the fitness range. Ideally you probably want to be in the athlete range, but it isn't necessary to lead a healthy life. When I began my journey to health I was around 25% body fat. Currently I am just over 15% and consider myself healthy. Even so my goal is to get down around 10%.
Another problem with just using weight to determine health is the daily fluctuations that occur. People who track weight seem to do it on a day to day basis. The up and down nature of weight leads to disappointment and frustration. People despair and give up rather than continue. A nice side effect to measuring body fat percent is it is something that doesn't make sense to do daily. It is something you do every two weeks or even once a month.
There is no room for daily frustration. If you follow the rest of the steps in this plan you will get results between measurements which makes it easier to continue until a healthy lifestyle becomes a habit.
