How do professional swimmers guard against getting asthma from chlorine in pools?

https://www.reuters.com/article/us-a...58E0N120090915

I swam for years but then developed dustmite allergy and mild asthma and i know it was from swimming,as i used to sneeze so much afterwards.

Recently went to outdoor lido as supposed to be better as fumes blow away but my nose still stuffed up next day and sneezed a few times I love swimming but not sure its safe for me?