I'm not married, but I would like to think that if I were, I could tell my wife about such things. I would make it very clear the purpose of taking the day off and emphasize that its for training, not chores. If you can, when you get home from such days, help out around the house - do the dishes after dinner, maybe cook the meal, put the kids to bed, whatever it is that your wife would normally take care of in the evening. Don't let her get into the habit of thinking "Great, he's going to train all day and I'm going to have to do all the work."