Re: Eating plan for day-long "strength" "workouts"
You'll probably need more carbs, and certainly more total calories, than you would on a less strenuous day. If it's hot and/or at altitude, be sure to replenish fluids and electrolytes, too.
Provided you get enough food over the course of the day, I don't think timing matters that much. So I'd suggest snacking as needed, but make sure you get a good solid lunch, too. If you're responsible for your own food, carry more than you think you'll need.