Customer Reviews
Great Bio-Impedence Fitness Tool 
2006-10-10
I've used these BCA units from Ya-Man for my fitness clients for several years with great success.
One important thing to keep in mind about bio-impedence fitness analysis equipment - the scales only measure your body composition from the waist down (up one leg, through the gut & down the other leg) and this BCA unit measures from the waist up (up one arm, across the torso and out the other arm. The scales and BCAs run this data through a formula to "approximate" the total body composition results. Thus what I've done is run both tests for my fitness clients and average the two together. This works great.
The nice thing about the BCA is it's portability and low cost and the results are within +/- 2% of the scales so they appear to by quite accurate.
My comments on the previous review: (1) early in their development Ya-man had some issues with erroneous data errors because they based some of their computations on statistics based on the Japanese population which is vastly differnent than our overweight U.S. population. These errors were fixed via the use of U.S. fitness data in the 2nd generation of the BCA. Chances are the previous reviewer either received one of these earlier units OR they failed to follow the directions:
To get good results it is important to be adequately hydrated, barefoot and standing on a solid surface with hands outstretched in front of you. If not properly hydrated the results can vary significantly.
What a waste of plastic 
2004-03-17
As soon as I saw this device, it seemed like exactly what I was looking for. It lets you analyze your body fat percentage, muscle mass, body water, and bone mass. If it worked it would be a "must have", for anyone who exercises. The ability to get instant results, and see from day to day if your gaining muscle, loosing fat, etc. But the problem is, it is completely inaccurate. For starters, I'm very slender, I've been tested professionally at about 12% body fat. When I try this machine, it would give anywhere from 20-24%, and put me in the "overweight" category. I can use it once and get one result, and use it directly afterwards and get a much different result. It was at the point that it was practically spitting out random numbers. I returned this item immediately. Wish a company would come out with one of these that actually worked.