Are breathing/relaxation exercises taken during readings cheating?

Weird question.

What I mean is that, during a sitting is it really appropriate to do effort to relax. The reason I ask is that, during the rest o fthe day we don't normally behave that way. While BP monitors can cause stress and that has to be taken into account, am I creating an artificial reading if I spend the minutes between and before readings doing deep breathing when I don't do that the rest o fthe day (I do some).

I hope this is clear.