Shoulder pain? Knee pain? Any pain? Mild conditions related to overuse would resolve with some rest.
Daily practices, dryland and swim meets take a toll on kids physically, and mentally.. and it can wear them out emotionally.
Is good to "miss" swimming. Enthusiasm ignites!
Burnout is one of the key reasons young athletes quit playing sports, and physical and emotional exhaustion can lead to burnout over time.
Allow them to catch up on schoolwork and spend time with friends. there's nothing worse than working on a crazy main set thinking on that homework you forgot to finish two days ago!
They will be better prepared to withstand the time and physical commitments of next week (or two) of training and swim meets.