With the arrival of fall and the beginning of the school year, it's a great time to get into a new fitness routine. While everyone has their own reasons for going to the gym and strives to reach their fitness goals, it can be difficult to accurately assess a person's overall health. A lot of people look to their Body Mass Index, or BMI, as a health indicator so we sat down with YMCA fitness guru, Dominique Pasqual, to get the scoop and learn more about the positives and negatives of a BMI assessment.
Y: Thanks for taking the time to share your fitness knowledge! What is BMI and how is it used?
Dominique: BMI stands for “Body Mass Index.” This number is calculated based on a person’s weight and height, and is used to determine if someone may have a weight problem. Although it is not a direct body fat measurement, it does correlate to body fat measures.
Y: How should a person interpret their BMI?
Dominique: BMI scores range from underweight to obese. While BMI does not give you an actual measurement of fat percentage in your body, it is a good indicator of whether or not you are a healthy weight for your height. If you have a high BMI, you may want to get a body composition test done which will tell you if your body fat is higher than a normal range. Keep in mind, someone who is quite muscular may have a higher than “normal” BMI, but because muscle is more dense than fat (one pound of muscle comes in a much smaller package than one pound of fat) this is nothing to be concerned about.
Y: Thanks for flagging that - definitely useful to know. Is BMI an accurate assessment of a person’s health/fitness?
Dominique: BMI is not a direct indicator of health or fitness. It’s a number that may not be accurate depending on someone’s body type, for example, two people that are the same size might have differing a differing BMI if one person has more muscles vs. fat. For this reason, BMI should not be the sole measurement of someone's health. BMI is a general guideline that is used to determine if a person's weight is relative to their height.
Y: That's good to keep in mind. Can BMI be used by everyone?
Dominique: BMI can be used for everyone, however when measuring the BMI of children and teens, age and sex are taken into account, whereas when measuring adult BMI, age and sex are not used to categorize results.
Y: I didn't realize that! What other details should people know about BMI?
- it is very inexpensive (free!)
- it’s a mathematical equation: weight (kg) / height (m)2
- this number should not be focused on when trying to assess someone’s health/weight. It is only a general guideline - more specific assessments are needed.
| BMI | Weight Status |
| Below 18.5 | Underweight |
| 18.5 – 24.9 | Normal |
| 25.0 – 29.9 | Overweight |
| 30.0 and Above | Obese |
Y: What other methods of body fat analysis should people take into consideration?
- skin fold measurement with calipers
- underwater weighing
- ultrasound technology
- bioelectrical impedance
