Hi,

I have a question about tanita body fat measure in the gym. I am gym member for 4 years now and I check my body composition about 3-4 times/year. They use Tanita scale to do that (TBF300A). The first line in the measurement is Body Type which they in most cases just put as Standard. This week however I went with my friend who has the same height, build and only 2-4 pounds lighter. While my BF was 22.8% and hers was 22.2% (which makes perfect sence to me) she said - how come, I was 16.8% 6 weeks ago! So they said - O, than you probably were using Athletic Body type before. Sure enough, this time around with Body type Athletic she evened at 17% BF.

Now is my question: why the difference in body type changes body fat by almost 5%? Another question - they said if we exercise 3 times/week - we are athletic - is it true? What is exercise in this case. Does it mean if I bike to work 3 times/week I switch from standard body type to athletic? To me it was a total nonsence and I would be glad if I could figure out if my fat is in its 20-ties or in its 17-teens?

Any advices? I know that BF measurements are very unprecise BUT 5% difference with the same device depending on setting?

Thanks,
Sandy.

Hi Sandy, lots of questions in one go.

Q1: About bodyfat measurements:
It's true that bodyfat measurement scales are not precise and may vary a lot between them. The reason is that on a scale like that a current goes through your body, measuring the resistance of your body tissue and calculating the result. Depending on water retention, muscle and fat mass, the results are not very reliable and may vary greatly according to the scale you use. So do not hang yourself up on the results, the only thing you will know is if you have gone down or in comparison to your last measurement on the same scale.
The best bodyfat measurement is still with plain multipoint caliphers.

Q2: define athletic. You cannot change your bodytype, you can adjust its requirements. Being athletic is being active and fit, not having a certain bodytype (superslim, tall, toned or muscled, whatever). If you want to get fit and into better shape, you have to push your body a bit farther every time you work out, but be careful! Don't hurt yourself. Have a look at www.stumptuous.com/ iron, lots of good, sound and free advice there.

Hope this helps,

Greekgirl