Not only numbers but also quality. And we are not talking about power here.
But there it was more about cases where we deceive ourselves, even our eyes deceive us. It may be anorexia or overweight.
And here the BMI calculator will come in handy.
but
Sometimes someone weighing little, within the BMI range.. will have a very average body.
No exercise, unhealthy food in small quantities or some forced vomiting.. and although the weight will be small, it will be bones covered with fatty tissue and skin. Without going any further.
A bit drastically described, but it is easy to distinguish a firm body from a "gelatinous" body :)
Unfortunately.
And this is not about a dig.
Without exercise, even small amounts of food can be stored as fat tissue on the buttocks or belly, without building any muscle tissue, which has great value and quality.
P.S. long walks are also exercise, it is a physical activity thanks to which we can build a strong body. Just compare people who do "beach" and those who hike in the mountains.