Most people want to lose weight and neglect the benefit of focusing on losing body fat. Let’s talk about a few good reasons to focus on our body fat percentage as opposed to body weight, or the number we see on the weight scale.
1. Most of us embarking upon a weight loss adventure incorporate aerobic activity and resistance training into their exercise regimen. But when we do this we must remember an important fact about muscle and fat. One pound of muscle and one pound of fat weigh the same, but the volume (or size) of each is significantly different.
Without a change in diet, studies have shown that changes in physical activity involving aerobic (i.e., cardio) exercise results on average in more fat loss than resistance exercise alone. However, when aerobic exercise is combined with resistance training, there is fat loss being accompanied by a concurrent increase in fat-free mass (i.e., lean muscle). An increase in lean muscle will yield slower weight loss results, but a potentially significant reduction of body fat and physical inches.
2. By definition, body fat percentage is the ratio of fat to lean mass within the body. It is typically calculated using weight, height, and waist circumference measurements. In addition to these measurements, there are a few body fat equations that also incorporate the circumference of the wrist, forearm, and hips. A 2012 National Institute of Health (NIH) study concluded, body fat percentage “plays a more important role in distinguishing between healthy and obese individuals, as it has a greater ability to differentiate between lean mass and fat mass compared to body mass index.”
The American Council on Exercise recommends the following as acceptable body fat percentages for men and women.
|General Body-fat Percentage Categories|
|Classification||Women (% fat)||Men (% fat)|
|Obese||32% and higher||25% and higher|
Most experts agree that a 1% loss of body fat per month is a generally safe and practical expectation.
3. Body mass index is another way to determine the healthiness of a person’s weight. BMI is calculated using an individual’s height and weight. The National Institute of Health has an easy online tool to calculate BMI. Several studies have linked BMI to various risk factors for diseases associated with overweight or obese patients. In general, higher BMIs correlate to unhealthy risk factors such as cardiovascular diseases, high blood pressure, type 2 diabetes, sleep apnea, certain cancers, and other illnesses.
Here is a detailed NIH chart that uses an individual’s height (inches) and weight (pounds) to determine BMI. Acceptable BMI limits are underweight (<18.5), healthy (18.6 to 24.9), overweight (> or =25), and obesity (> or =30).
In summary, I encourage you to calculate your body fat percentage and BMI numbers. As you know, both of these numbers are calculated using your body weight and other body measurements. Use these numbers to set new fitness goals!