body fat

scotty38886

OK I am confused , I had myself weighed on one of those fancy machines at the gym and again 3 days after (today) I did this because I am going to have a regular weigh in on a saturday, now according to my results in 3 days i have lost 0.2kg , at the start my bmi was 10803 and today it is 10606, BUT my fat% was 34.0% and today its 34.5%. Could any one explain why it has risen even though my bmi has lowered and i lost a spec of weight? Thank's in advance.

LisaZaugg1976

I would not go by those scales.

KokomoJoe

I have an electronic scale and figured the body fat since I was using the same scale every time would be accurate. However over the last 2 weeks when I started monitoring body fat it has shown everything from a body fat of 31 to a body fat of 42. It's gotten to the point where I know it's useless but I like to see what the magical mystery scale has to say today. I figured it would be accurate enough to show progress but I believe it is incredibly inaccurate.

scotty38886

why?

Azdak

Even a good bioimpedance scale is going to have daily fluctuations because it is looking at total body water. To be the most accurate on those scales, you must try to weigh yourself under the exact same conditions and hydration status each time. Often that is not possible; in that case you need to weigh yourself several days in a row and get an "average" trend.

Unfortunately, those are just the inherent inaccuracies of the method itself. Body fat does not change that quickly anyhow--anything less than a 2%-3% change is going to be within the standard of error anyhow, so getting caught up in daily changes is a waste of energy.

KokomoJoe

If your machine at the gym uses the Bioelectrical Impedience, from the research I did Scott here is what I found:

The relative accuracy of Bioelectrical Impedence measurements is HIGHLY dependent upon the conditions under which the measurements are performed. Factors that can sway the results include:
- Time of day
- Hydration level
- Food and water intake
- Changes in blood circulation from environmental temperature changes
- Recent changes in posture (like from lying to standing)
- Recent exercise
- Alcohol consumption
- Swelling / water retention

scotty38886

I heard to notice a change the best thing is to measure ones self . Do any of you find that to be correct?

Azdak

I heard to notice a change the best thing is to measure ones self . Do any of you find that to be correct?

It's hard to get accurate measurements on yourself, but, yes, that is always a good backup. Circumference measurements, if done accurately and at the same locations, provide some of the most reliable evidence of fat loss.

You cannot use circumference measurements to give you a reliable body fat % number (there are calculators out there using circumference measures, but they are not accurate at all), but it is extremely reliable at measuring absolute changes.

scotty38886

thank you very much

KokomoJoe

I use my scale as an example. I got up did my business and weighed myself. I was 265 and 41 percent body fat. I went and drank .5 of water then went back. I was still 265 but it read 38 percent. That was 30 minutes later with more water in me.