What does BMI stand for and what does it mean to an endurance athlete?
(BMI) stands for Body Mass Index and it is a very basic body measure which has been put together to assess if you have a healthy level of ‘fatness’ using an equation that involves the relationship of your height to your weight.
Your BMI is calculated in the following way: BMI = Weight (kg) / (Height (m))2
BMI value calculated is then classified in the following way;
· Underweight = 18.5
· Normal weight = 18.5-24.9
· Overweight = 25-29.9
· Obesity = BMI of 30 or greater
Although BMI, is a good measure for much of the population, the only problem with this measure is that it doesn’t account for muscle mass and can give questionable results in athletes and sports people. In muscular body types — particularly body builders or other stocky athletes such as rugby players, the BMI might suggest that you’re fat even though you’re lean and healthy. The BMI equation can’t be adjusted to take into account an athletic build so highly trained athletes are at a greater disadvantage: their excess muscle typically puts them at a higher BMI, so they may actually be considered obese. Athletes have a body fat percentage that’s lower than that of the general population. A normal body fat percentage for women is between 25 and 31 percent, and, for men, it’s between 18 and 24 percent. For athletes, body fat percentage usually runs 14 to 20 percent for women and 6 to 13 percent for men. If you’re female, and your body fat runs 32 percent or higher, or, for men, 25 percent or higher, even if you’re athletic, you may be overly fat and have an increased risk of health complications. There are many other measures which are more useful which you can use instead to determine if you’re at a healthy weight.
For example you could get an estimate of your body fat percentage using a specialised scale or have a fitness professional use body calipers for the measurement. There are other more precise methods, such as underwater weighing and DEXA scans, which require more expensive equipment. Measuring your waist circumference can be a better measure of fatness. Not all fat stored on the body comes with the same risk to your health. If you’re male and have a waist bigger than 40 inches or a female with a waist that’s bigger than 35 inches, you have more harmful deep abdominal fat and with it a higher risk of chronic disease.
If you’re an athlete you could be what is known as ‘skinny fat’ meaning that although you appear muscular, you’re carrying too much around your middle.
The good news is that fat carried around your middle is mainly diet related so you can shed it quickly by increasing your intake of vegetables, fruits, lean sources of protein ie meat and fish and getting rid of highly refined sugary foods, processed foods, most fruit juices and anything that comes in a wrapper with ingredients that you can’t pronounce !