body fat percentage :/

I would def double check that.. cause it makes no sense to me at all!! Good Luck!

What kind of machine?

hydration levels can affect body fat percentage. I am not a doctor or trainer, but when I had a personal trainer she said that it was important to be hydrated throughout the day and not to check it after your workout since you may have sweat out a lot of the water.

You definitely need to check it in the am before eating / chugging down liquids / food.
Also post exercise will screw up the results as well...

I use the machine at the gym and a caliper at home (cheap and accurate take very little skill -$5 or you can sometimes get one for free with your order from retailer - bodybuilding.com)

If the body fat measurement was taken with a bioelectric impedance device (like electronic scales) then the time of day makes a large difference due to the water retained in your body. They are also only accurate within a significant margin of error - something like 5 or 6 percentage points either way. (i.e. it might tell you you are 34 but you might be 29 or 39). If you went up in body fat percentage, that probably means that you were less well hydrated the second time you were measured.

If it was a skin fold test with calipers, they have a margin of error of something like 3 or 4 percentage points each way and are very sensitive to user error.

I spent an age looking into body composition testing last year. The only way to get an accurate measure is to get hydrostatically weighed (weighed under water) or weighed in a device such as a bod pod - which works by measuring air displacement. This is because it is necessary to take account of volume to get an accurate composition reading.

It isn't easy to find this service. I am in London and had a bod pod assessment done at the University of Westminster by a PhD student in the sports science and nutrition department. They used to do it for about £25. It was very interesting. I had been measuring my body fat on electronic scales (which I had noticed varied widely depending on how hydrated I was). The bod pod estimated by body fat was 5% lower than the scales, and was about 4% lower than a skin fold test with caliper. The scales had been telling me I was 18% body fat, skin fold results were telling me 16% and the bod pod told me I was 13%. The bod pod (happily!) is by far the most accurate measure.

In short - don't rely too much on electronic scales and skin fold tests. They are useful to give you running progress indicators, but they are not very good at giving you an accurate body composition assessment.

Caliper assessments are way more accurate then BIA.

Yes, that was certainly my experience. It's so disappointing - the electronic scales promise so much!!

I think BIA devices hurt more than help. They make you do things that are not warranted, mostly because of hydration which is usually inconsistent.