Posted Date: October 6, 2008
Fitness trainer Kimber Chase offers another way to measure fitness and describes an easy way to get started on the path to good health.
Most people are familiar with the health risks of being overweight: high blood pressure and cholesterol, gall bladder disease, osteoarthritis, sleep apnea and respiratory problems, type 2 diabetes, some cancers, stroke and coronary artery disease. Can we tell by looking at people if their body fat is too high? What is too high? Can we decrease these potential health risks? How do we healthfully decrease our body fat and gain lean muscle tissue regardless of our age and medical conditions?
It is encouraging to see that many of you are using dog agility as a motivator to lose weight, get fitter, stronger, and develop better running skills. It has been mentioned previously that a goal is something that can be measured, not just seen. So how do we measure our weight loss? One reliable method of measuring weight loss over any period of time is by body composition testing, and by taking body measurements. Obvious changes in athletic ability such as increased speed and strength, better timing, ease of breathing, and recovery are usually felt by most people a short time after beginning (or altering the intensity of) an exercise program. We also all know whether our clothes fit tight or loose.
When you jump on the scale, just what are you weighing? Your total body weight. Our bodies are comprised of fat mass and fat-free mass which is blood, bones, muscles, and water (50-60%). Body fat percentage refers to the amount of body fat mass in regards to the total body weight described in a percentage. Knowing our body fat percentage is valuable when adjusting our exercise programs weekly, monthly, and yearly while trying to become more fit.
Body mass index (BMI) is calculated from a person's height and weight and correlates to body fat. It is also used as a screening tool to evaluate potential weight problems. To determine if weight is a potential health problem, other health assessment is necessary. Normal body fat percentages, those not associated with risk for disease are approximately 12-20% for men, and 16-25% for women.
We can not tell by looking at someone how much body fat they have because genetics makes up so much of our muscular appearance. Two people with the same body fat can look different. Some people maintain more of an elongated look, while others look more defined. Generally speaking, women have more body fat than men, and older people have more body fat than younger adults. Athletes may have a higher BMI because of more muscle density.
To add another dimension: most people are surprised to learn that muscle per unit of volume is three times heavier than body fat. Muscle is also active tissue in that there is blood flow to muscles. Muscle you build from exercise will be active all day long in burning more fuel. So, anyone serious about weight loss could also consider building and maintaining muscle from exercise a priority. Since muscle weighs more than fat, as we exercise, we are likely to gain weight at first. This is why knowing our body composition can be advantageous while changing our nutrition and exercise programming.
There are several ways to determine fat-free mass versus fat mass. Important to note is that each means of measurement is only as good as the observations/rules and guidelines associated with the particular testing procedure. One method used extensively on athletes over the years has been underwater or hydrostatic weighting. These are big machines/tanks and considered the most accurate. However, not readily accessible to most of us average folk. Another common method used in health clubs is using a caliper to measure skin fold thickness on various parts of the body. This method is relatively accurate but is dependant upon having the same administrator on repeated testing. Electrical impedance is also commonly used. With either a hand held device, or a standing scale, body fat is estimated from body water since different tissues have different amounts of water. A weak current is sent through the body, and then registered by the analyzer device. Hand held units have a 3% margin of error. Some of you may be familiar with home scales that can be purchased which tell us our body fat percentage. These use electrical impedance. Scales have a 5% error margin, and the scale usually doesn't know our height, how much we exercise, or our age. Conditions of testing and consistency are always important. We must be hydrated but not under or over hydrated while testing, so we don't want to test after exercising, and preferably not at night. We test every 6 weeks to effectively monitor changes in body composition. This can be very inspiring too! If you know that test is coming it keeps many people on target with their fitness goals.
Check back tomorrow to learn how we change our body composition.
Kimber Chase, CFT, AFT has been certified fitness and aquatic trainer for 15 years. She lives in South Florida and has been competing in agility for 9 years with two border collies. She can be reached at email@example.com or through her website at http://www.completephysique.com/.