If you get it white you'll be tempted to bleach it, which I'm told shortens its lifespan horribly.
! We haven't had bleach in our house for at least 10 years -- though it's great for making dioxins in the environment.
Try a laundry grade hydrogen peroxide, a.k.a. non-chlorine bleach
, to get those sweat, grass, and blood stains out.