Can a child of 13 with cystic fibrosis play vollyball without struggling?

It's possible: Not all children (or adults) with CF have significant respiratory issues. So, many children participate in sports with some or no problems. Using their inhalers may help tolerate activities better. Care should be taken to exercise in moderation, not to exhaustion. Additionally, the risk of dehydration may be higher with this disease, so drinking fluids is very important during sports.

Cystic fibrosis: Cystic fibrosis children has limited lung capacity that gets worse overtime. It will be difficult to participate i sport with limited lung capacity. Most children with cystic fibrosis end in lung transplant by early 20s.

PFTs with albuterol: An additional comment: children with CF can participate in sports if they are able to do so. Obtaining a lung function test with and without a bronchodilator to determine whether there is treatable reactivity of the airway may be useful. This can be discussed with your doctor.