 Setting a 30-minute timer on your phone after eating before you hop into the pool? Doctors say you can knock that off, as in most cases, there's no need to wait unless you're planning to swim laps or exercise in the water. It's a decades-old warning based on worries that people might drown or have trouble in the water because blood would be diverted to their stomachs rather than their muscles. Allison Keys, CBS News.