I do rolling 48s and run 24 miles per week, but it is 4 miles 6 days a week. So a little different than you. I don’t drink coffee, green tea instead. I don’t drink green tea until after my runs, late morning. I think you will be fine, you are probably second-guessing yourself because the 48s are new to you. You’ll adjust pretty quickly I suspect. All the best to you!
Check out Evian French Alps Spring water. That stuff has KCl in it.
When I first got into fasting I started the Snake Juice Diet, KCl, pink salt and baking soda mixed in with water whole fasting. I worked construction dawn to dust five days a week while fasting. Ate on the weekends. Did that for like 3 months, lost my strength due to keto transformation, then regained it after a month or so.
Exercise worked great for me whole fasting. Not exercising on the first day of the fast isn’t the same since the exercise really can kick you into ketosis.
But ye, I keep them electrolyte levels up when fasting more than 24 hrs.