I understand you're concerns about manipulation of ions-- electrolytes during different phases, such as one in competition mode. Yet, this discussion isn't talking about one prepping for a comp.
If we're pumping in large quantities of water along with excessive sweating; and excessive urination without sufficient Na intake, this can easily set the stage for hyponatremia-hypovolmic. Most hard training athletes will loose approximately 1,000mg of Na too upwards of 4,000mg. 3,000mg of Na is a far-cry from excessive over-manipulation.
Something else female's more than likely do not know; is durning different phases of their menstrual cycle---more particularly their luteal phase (12-16 days from the day of ovulation, or ovulation until menstruation) is when Na levels are much lower than any other phase.
I mentioned the use of iodized salt. This is a crucial nutrient not only for proper thyroid function. The use of iodine salt and has been associated with the reduced risk of breast cancer and fibrocystic breast disease. As well has been observed in some settings to reduce cyst mass in those with PCOS.
It would be of my opinion, that if I'm subjecting myself to the aforementioned, I would not hesitate to up my Na intake.
You'll notice, I was the first and only male to identify PFD... I'm working towards being a P.A. I have a fairly good understanding of this.