A muscular 30-year-old client has a BMI of 29 kg/m², but skinfold testing estimates his body fat at 12%. How should the trainer interpret these results?
Show answer & explanation
Answer: C
He is obese, because a BMI near 30 always means excess body fat: BMI can't tell fat from muscle, so it doesn't always reflect body fat in muscular people.
The skinfold result must be wrong, since it disagrees with the BMI value: A disagreement between BMI and a direct body-fat estimate is expected in muscular clients. It isn't proof that the skinfold test was wrong.
His BMI likely overstates fatness because of his high lean mass: Correct. With a relatively low body-fat percentage, the high BMI reflects muscle mass. Body composition is the better measure of his fatness.
He needs a calorie deficit right away to reduce his BMI below 25: Programming weight loss to lower BMI would be inappropriate when his body fat is already low.
BMI is a screening tool based only on height and weight. For muscular clients, use body-composition measures to judge fatness.