I don't think you get "more points" for playing multiple sports in and of itself. It's more about the big picture - how much time do you commit to your sport(s) while juggling a full school course load and other activities? How do the sports you play challenge you physically and mentally. Are you a team player? A leader? If I'm a admissions board member (which I'm not) I'd probably look more favorably on the one sport swimmer practicing 25 hrs a week then the candidate who plays several recreational sports part-time. But again it depends on the broader context.