The abbreviations BMI and BMR sound similar, but they stand for two separate things. Your BMI, or body mass index, is a number calculated from your height and weight which is then used to assess your body composition. Your BMR, or basal metabolic rate, is the number of calories you burn when your body is at rest.

With so many images in the media of very thin women, some people will diet to try to fit in with this idea of beauty and in the process become so thin that they're unhealthy. Others may be overly thin for different reasons, but whatever the cause, it isn't healthy to be underweight.

NFL quarterback Jay Cutler was the victim of body-shaming after his wife, Kristin Cavallari, posted a photo on social media.

Because a number of factors can affect metabolism, there isn't a particular age when a teen's metabolism slows down -- it varies from one teenager to another.

Accuracy varies among fitness-assessment protocols and should be considered when choosing methods of body-fat testing.

Many herbs may help slow your heart rate. According to MedlinePlus, your heart rate, or pulse, is the number of times your heart beats in one minute while you are at rest. Numerous factors can affect your resting heart rate, including your fitness level, your age and your health status.

The breasts consist of ducts, lymph nodes, blood vessels and lobes, but they also contain a great deal of fat. When it comes to weight reduction, your body loses fat as a whole instead of in one specific area.

Failing to meet U.S. Army weight and height requirements may disqualify you as a potential recruit. Although as of January 2009, the Army does have a weight waiver that, in some cases, may allow you to enlist and lose weight during basic training, height requirements remain firm.

The urinary system consists of the kidneys and bladder, along with the ureters and urethra. It has multiple functions, among them excreting toxins and metabolic by-products, maintaining the body's fluid and acid-base balance, regulating electrolyte levels and secreting several important hormones.

While having a high percentage of body fat can contribute to many chronic diseases, not having enough body fat can be just as dangerous.

The American College of Sports Medicine is the largest sports medicine and exercise science organization in the world, with over 20,000 members. Founded in 1954, the ACSM has continued to provide research, education and certification opportunities for individuals in the fields of sports medicine and exercise science.

Most female athletes carry between 8 and 15 percent fat, but swimmers usually have a bit more -- between 14 and 24 percent. While any body fat percentage below 30 is perfectly healthy for a woman, it's expected that competitive athletes be among the leanest and sleekest people around.