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24 Nov 2004

I have a controlled eating plan (± 2 weeks on the eating plan) and have started training in conjunction with this to assist with weight loss. I have asked the fitness consultant to work out a program which I started on Saturday. My concerns is this:
On the 15/11, I weighed 74.9kg and my body fat % was 33.7%
On the 20/11, I weighed 75.1kg and body fat % was 20.3%
On the 23/11, I weighed 71.1kg and body far % was 22.3%
My question : Does this seem odd or is it possible to have lost 4kg in three days (NOTE: I need to lose about 20kg). Is it a bad thing for my body fat % to have increased?

Answer 398 views

01 Jan 0001

Hi Zoe

Two of the things that are very important when doing any measurement are 1) the accuracy/validity of the machine, and 2) the 'competency' of the person doing the measurements. This may sound like a pretty obvious statement, but not too long ago, someone found that the scale in their gym was telling them they had gained 6kg in a week, and after then comparing other scales, found that the one in the gym was in fact overreading by 6 kg. Remember that any piece of equipment is bound to have faults, you can never guarantee that it will be 100% accurate, and while this is an unlikely answer, I would check it out first.

Now, as for the second point, I refer mainly to the body fat measurements. I don't know exactly which method you have used but some are less accurate than others, and some require that people use the subjective opinion to take measurements, like the body fat reading using the skinfold calipers. Again, I'm speculating, but I am more amazed that your body fat could have dropped by 13% in one week - that's not possible, and the only explanation for that is that you have either had an equipment malfunction or the measurement is not accurate. I don't mean to be harsh, but in Australia, before you are even qualified to take measurements, you have to pass a test in which you take at least 1000 readings accurately. If it is the BODYiQ method you have used, then I suggest that you just do the measurement again tomorrow and make super sure that the equipment is the same as it has been on previous occasions - you have to always line the reader up accurately with your biceps, and make sure no light gets in (If you don't know what I'm talking about, because you don't use this machine, then don't worry).

Finally, the weight loss issue can be explained simply by looking at most of this as water loss. For example, if you weighed yourself on the first day having just eaten and had something to drink, it's quite possible that you could have added another 2kg instantly. If you then weigh yourself after not eating or drinking for a while, you lose those 2kg, plus maybe another 1, and there's 3 kg for you right away.

So, the bottom line is to avoid making very instant comparisons - you have to look at the big picture over many weeks, not one. If you do this, then one dodgy reading suddenly gets put into context. So, I would continue doing what you are, and then about 2 weeks from now, do measurements again, then maybe 4 weeks later and so on.

Good luck
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