Question: What are the benefits of cross-training?
Answer: Well, the primary benefit of cross training is that by participating in a variety of activities, instead of just one sport or one exercise day after day, you avoid doing that same movement that's involved in that sport. [Doing] too many movements in the same plane in the same direction every day can lead to overuse injuries with the muscles, even the bones with stress fractures. So that would be the primary benefit ... injury avoidance.
Secondary benefit would just be the variety can make things fun -- you don't get into the same routine, the same rut. That can keep you mentally, as well as physically refreshed.