Epidemiologists estimate that approximately 80% of all common diseases are linked to body fat and an inactive lifestyle. Fatty adipose tissues produce hormones that directly influence metabolism. A study from the National Center for Tumor Diseases illustrates how significant this impact can be.

A group of 439 overweight female subjects was divided into three groups: Just diet, diet plus exercise or just exercise. After a year of dieting, working out or both, researchers found that all groups produced less leptin, which plays a key role in regulating energy balance, and more of the anti-inflammatory adiponectin. Changes were greatest in women who lost 10% of their original body weight.

True Strength Moment: Scientists theorized that a combination of diet and exercise would result in a more favorable balance of these two hormones. We’ll assume the intervention also resulted in a better balance of body fat to fat-free mass (muscle).