yup, both help a ton, sarah.
but the best thing is to keep out of the sun/heat.
those kids must sweat i can imagine, to the above posters, because i'm sure most have had sweat tests to diagnose CF, right?
but ya, i get overheated very easily myself and in addition to drinking gatorade and eating salt pills, i just plane stay out of the sun and heat.
it's not worth drying out my secretions in my lungs and risking an infection.