In relaxation before hand

I am really good about the quiet before the storm so to speak. I have a race on Thursday and I spend anywhere between three to five days before a race cleaning, relaxing and prepping for the race. You know, trying NOT to get injured. But, as I am going for my second 5k I am wondering if resting before the race is still necessary. When training I run about a distance of 2.5 miles- 3.5 miles give or take. If a 5k is 3.1 miles, I am not sure if resting before the race is necessary. Will report how this will end.