I'm definitely a frustrated musician, though it's more in terms of wishing I was a better guitar player and songwriter. But I've never regretted becoming an actor instead. I think it's been a more pure form of self-expression for me. I luckily found something that I could aspire to be good at, whereas I never. . . I think I'd never quite reach that level of artist that I enjoy in the music world.
You can do as many sprints as you want but there's nothing like playing in a 90-minute soccer game. There's no better way to gain your fitness, in my opinion, than playing in consistent games.