Yes, muscle is heavier than fat so someone who workouts out frequently would show up as obese. The numbers could also fluctuate due to changes in percent body water. It’s far better to use percent body fat for athletic builds. There’s cheap body fat scales and hand held devices available to buy from many retailers. They aren’t accurate at measuring your percent body fat but are very precise at measuring your changes in your percent body fat.

He takes roids or he used to take roids.

Hypermuscular people are so rare that they really don't count. Many steroid users fall over dead in their 40's or 50's from heart disease.

I love watching football but I don't think an NFL defensive lineman is a good model for being healthy.

I'm certainly not going to argue that taking steroids makes one healthy. My point is health cannot be determined by measuring height and weight.

BMI is for measuring normal humans, not rocks