Usually the recommendation is to take short, no longer than 30 minutes naps. Supposedly, after 30 minutes you go into deep sleep and waking up will make you feel tired. I haven’t reviewed the scientific validity of the claims, but it has always worked for me.
If you have enough light, close your aperture to something like f10 or higher, and increase your ISO to some value where you’re comfortable with the noise, like 6400. Test different shutter speeds depending on the action that you’re trying to capture, but the small aperture will help with the focus.
Maybe try manual focusing too, at small apertures you can set a large focus plane that will capture all the action.