myrridin

What I think may be confusing you is the concept of measuring. Those electrical devices don't actually measure body fat. As far as I know their is only one way to actually measure percentage body fat and that requires measuring unsubmerged weight and comparing it to submerged weight.

Those electrical devices measure an electrical property, like conductivity, and using the adjustment factors estimate body fat when compared to real measures from real people broken down by category. They are based upon the fact that such an electrical property can have a predictable relationship to body fat percentage.

Journeyman

The difference is the older rider has to work a lot harder than the younger rider to maintain that level of fitness.

VaultGuru

I also had the same question when I was tested at the UC Davis Human Performance Lab last year. I am 65 and by body fat was 13%. The doc said if I was 15 years younger, I would be around 7%. Why? Here is an article that explains it.
https://www.merckmanuals.com/home/sec...20/ch320b.html

alcanoe

How much fat you carry is not just do to exercise/activity. It's also a function of diet type, and calories in/out and very importantly your body type :

https://www.bodybuildingpro.com/bodytypeinformation.html

Some of us just naturally have more body fat than others. We probably had an evolutionary advantage as before mature civilizations, it was normal to go from feast to famine.

I'm a cross between an endomorph and mesomorph. I can build muscle mass quickly and tend to carry a higher percentage of fat. That's my natural state so I don't fight it, nor are there any negative health consequences in being myself. There is no way I'm built for biking anyway.

My father in law looked like a definite endo and had the big gut. When they operated on him for appendicitis, they said it was pure muscle. Since he worked in construction, it was not too surprising.

As far as hormones falling off with age, the biggy is HGH or human growth hormones. Big negative consequences for losing HGH and it goes quickly after 40. Exercise, particularly of the strenuous kind (heavy weights and high heart rate endurance) keeps the HGH high and all the effects of aging far subdued compared to the sedentary.

Al

jackb

More tyranny of numbers. If you want to find out if you're overweight or fat, take off your clothes, stand in front of the mirror, and look at yourself. What do you think? As for fitness, pedal fast up some hill. How was it? You know what you are. No need for all these numbers.

8Lives

If you are going to measure accurately try to find either a bodpod (many University's have them) or Dexa scan. $60 or so, worth testing a couple of times a year. Data good, guesswork bad.

https://www.bodycompositioncenter.com/

Aaron

Lucillle

My opinion only: Given the recent spate of articles about medical error/bad equipment and xray injuries, I would have to be in dire need prior to permitting any kind of radiology.

cyclinfool

Larry,

In the responses there are a few answers to your question. In general all measurements including the tank tests are indirect measurements, they take the data (electrical resistance, folds of skin, water displacement, etc) and based on how the typical body distributes weight (based on age, sex, height, etc) estimate what your body fat is. BMI is just a simple mechanism to normalize weight for height and other factors so you can say where your weight falls based on the average population. It is too general to be used for athletes.