Most people don't like going to the gym in the Summer, but I go all the time because it's nearly empty and I don't have to battle people for access to the equipment. I also get to spread out and enjoy a little peace and quiet during my workouts. August is the best month to find an empty gym. Going outside is great and I do try to workout at least 3-4 times outside during the Summer, but if you want some peace and quiet at the gym, try going in Summer!