Bioimpedance and hydration: why the number moves

Bioimpedance and hydration: why the number moves — setting out what I have, and where I think it stops being reliable.

I have spent a fortnight trying to pin bioimpedance and hydration down and I want to set out where I have got to, because I suspect the honest answer is duller than the thread this will produce.

What I have: a consistent observation across a small number of cases, collected the same way each time. What I do not have: any controlled comparison, or any reason to think my cases are representative.

The specific question is whether the pattern survives once the obvious confounder is removed. I cannot remove it with what I have.

Agreed on bioimpedance and hydration, with one qualification that I think matters. The reasoning holds for the case as described. Change the starting assumption and it does not, and the starting assumption is the part nobody states.

Photographs under fixed lighting and posture are a genuine record and are the hardest of these to standardise.

Marking my uncertainty on bioimpedance and hydration explicitly. I am confident about the direction, much less confident about the size, and not confident at all that it generalises past the case in the first post.

Grateful for the specificity. Vague answers to this question are what sent me looking.

Standardise the conditions: same time of day, same hydration, same recent training, same machine. Most of the variability is protocol rather than physiology.

Bioimpedance and hydration is well covered in the tag pages, and the older discussions are better than the recent ones because they were argued out properly. Worth twenty minutes before adding to this one.

Taking post #7 at face value and following it one step further.

Reading back through the bioimpedance and hydration threads from last year, the same three questions come up every time and only one of them has ever been answered properly. That seems like a documentation gap rather than a knowledge gap.

Bone mineral density changes with substantial weight loss are measurable and slow, and are one of the better reasons to have a baseline scan.

My experience of bioimpedance and hydration contradicts the reply above. I am posting it as a data point rather than as a refutation, because one person's experience is exactly that.

Answering the bioimpedance and hydration question as asked, then the question I think is meant. As asked: yes, with the qualification below. As meant: it depends on how the first measurement was taken.

Reading back through, this was answered upthread and I missed it. My fault.

The most useful protocol is the one you will actually repeat identically. An imperfect measurement repeated consistently beats a better one repeated carelessly.

Take it as a starting point and not as a specification.

Worth separating two things that post #10 runs together.

On bioimpedance and hydration: the maintained page in the documentation commons covers the general case with citations and a review date, which is more reliable than any reply here including this one.