P.R.
Hello,
My 5 yr old had this problem last year I took her to the Dr and we thought it was activity induced asthema (spelling?)But it ended up being allergies. The doc prescribed her Zyrtec and it hasnt happened since.
I would recommend taking a trip to the Dr to make sure its not Asthma...allergies arent so scary but asthma can be.
Hope this helps:-)