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Â At stores for about a year now, the InnerScan scales that are sold under both the Ironman and Tanita names promise a lot for a teeny step-on scale. These go way beyond the Tanita scales renowned for their ability to measure body fat, adding the ability to tell a user his or her body WATER level (how dehydrated are you?), as well as muscle mass, daily caloric needs, metabolic age, bone mass (not density) plus of course body weight. Some models also are said to measure “visceral fat,” i.e. the deep stuff that can be the truly disease-threatening type, and give “physique ratings.” The line is branded both InnerScan and Ironman, but they do nearly the same thing, except the Ironman line also gives users base caloric needs based on a measured basal metabolic rate, with the assumption users are more advanced and can calculate or need to calculate caloric needs based on varied athletic activity.
The model several SNEWSÂ® testers used for about four months was the Ironman 553, the middle of the three current models, which did not have the visceral fat reading or the physique rating. Additional models will be out soon too that add sleeker glass tops.
We used the scale off and on during training for endurance events by users who had either been in regular training or had been in the past and were now getting back into it more regularly. None was however trying to lose great mounds of fat or gain great gobs of muscle, which seem to be the best uses for the scales –Â someone who really is trying to change his or her body composition for one reason or another, be it health, fitness, training or just because.
What we found were swings in percent body fat and the percent body water that left us confused â€“ if one went up, the other went down. And of course we all know that you can’t gain a couple of percent in fat in a few hours, although you can lose that much body water if it’s hot enough and you’ve worked out hard enough. But since our testing was done between December and April, the days hadn’t been hot enough for huge water losses.
Although there have been plenty of studies over the years validating the readings done by the “Bioimpedence Analysis” (BIA) used to measure body fat, we weren’t offered any to validate the body WATER readings. Basically BIA, a scientific method used at universities, sends a harmless bioelectric signal through your body, which is conducted by the water. The more water you have in you, the faster it goes and the more accurate the readings, Tanita says. That implies that if you are hydrated, then your body fat percent will allegedly be more accurate. But if you are dehydrated, the signal goes slower and reads as higher body fat.
Since your body’s shifts in weight and composition from day-to-day and hour-to-hour can make too much measuring too confusing, it is of course important to focus on trends. One of our users noted a downward trend in weight over about six weeks (not a positive thing in this user’s case), so a goal to eat more was added to the to-do list. Another user noted a (positive) trend downward in weight and realized more serious training was indeed helping in the loss of a handful of extra pounds.
But, beyond that, our testers weren’t sure where to start with the fat-water readings: Sometimes stepping on the scale after a 60-90-minute winter run (during which our tester may have slurped 16-20 ounces of water) still showed a drop of a pound or two in weight, although fat and water were relatively constant. Remember, a pint’s a pound the world ’round, and there is no way someone could down another 16-20 ounces or more on a short, cool winter run. Another similar run showed the tester having gained 2 pounds, when only 16 ounces (a pint) of water was downed, but fat and water were still insignificantly different.
We even tested its weight sensitivity a couple of times, stepping on it, then stepping off and downing 8 or 16 ounces of water and stepping back on. Yup, there was that extra half-pound or full pound (Of course, the body hadn’t assimilated the water in a few seconds so it did not change the body water reading).
A Tanita spokeswoman shared with us her story of working to get her body weight and fat down after having had a baby, and the trending seemed to make sense and be helpful to that attempt to change body composition.
All in all, we love the sleek look of the scale, and we love being able to monitor digitally our weight. In fact, it’s been quite addictive to see the numbers and how they can fluctuate over the course of a day even. But unless you are truly trying to change your body composition, we’re not convinced the fat or muscle readings will do much for you.
SNEWSÂ® Rating: 3.5 hands clapping (1 to 5 hands clapping possible, with 5 clapping hands representing functional and design perfection)
Suggested Retail: BC 553, $120 (other similar models by Ironman or Tanita, $100-$130)
For more information:www.tanita.com