Body Composition- The Basics

How much you weigh can be a heavy problem- but have you considered your body composition?

 Body composition refers to the proportion of fat and fat-free mass in the body. Those with a higher proportion of fat-free mass (muscle, bone)  to a lower proportion of body fat have a healthy body composition.

Obesity, Thinness, Leanness. What's the difference?

• "Obesity" refers to having excessive body fat leading to serious health issues such as hypertension, type 2 diabetes, joint problems, as well as heart and breathing issues.
• "Leanness" refers to the muscle, bone, and fat composition of your body weight. Although some lean individuals may actually weigh more than their "tabled" ideal body weight, low body fat lessens the risk of health problems. 
• "Thinness" simply refers to weighing less than the recommended values in age-height-weight tables.

According to the Center for Disease Control and Prevention (CDC), childhood obesity has more than tripled in the past 30 years. The CDC states that childhood/adolescent obese children are likely to become obese adults. Eating and exercise (or lack thereof) habits learned as a child and adolescent may be difficult to undo as a working adult, stressing the importance of encouraging our students and athletes to live healthy and active lifestyles.

Many athletes may be categorized as overweight or even obese on some charts due to their muscle weight in relationship to their height. While it is mildly important to know how much you weigh, it is much more important to know how much of what you weigh is fat. Our bodies need a specific amount of fat to function, but not too much.

Ways to assess your body composition, and body fat percentage, include measurement with calipers and composition analyzers,  body mass index tables, underwater body fat tests ,and the bioletrical impedence analysis (BIA). Sports Health offers a variety of body composition tools such as body scales with BMI function, body composition analyzers, and BMI calculators.

BIA measures how difficult it is for an electrical current to move through the body. The electrical current is so small that most people cannot feel anything. The more body fat one has, the harder it is for the electrical current to flow through the body. The less fat one has, the easier it is for the electrical current to flow through the body. This means your body's fat stops (impedes) this controlled electrical current, allowing the technician to assess your percent body fat.

The body mass index, BMI, is used to calculate a person’s body fat content based on his or her weight and height. The World Health Organization (WHO) has used the tool to calculate obesity rates since the 1980s. Despite its popularity, one major shortcoming of the test is that it doesn’t take into account frame size or muscularity of the athlete. Therefore, even a professional athlete may fall into the “obese” range on the index scale because of the weight of muscle on his or her frame.  The CDC has BMI calculators for adults and children- where do your students and athletes fall on the chart compared to their body composition?

Adult BMI Calculator  http://www.cdc.gov/widgets/#adultBMI
Children’s BMI Calulator http://www.cdc.gov/healthyweight/assessing/bmi/index.html

This blog was written by Phil Hossler, ATC. Phil has been an athletic trainer on the scholastic, collegiate and Olympic levels. He has authored 4 books and numerous articles and served as an officer in state and regional athletic training associations for 20 years. He is a member of four halls of fame including the National Athletic Trainers’ Association’s.