http://islamqa.org/hanafi/askimam/11142
Question
I have a back problem and it has been recommended that I swim. I do not swallow any water and use ear plugs to prevent water from entering the ears. Without swimming my back begins to pain after two weeks.
Answer
It is permissible to swim in the state of fasting .
And Allah Ta’ala knows best
Mufti E. Desai[/quote]
[quote]
Q- Is swimming permissible whilst fasting?
A. It is not advisable to swim whilst fasting. If water is swallowed by mistake or enters through the nose and goes beyond the nasal bone, reaching the nasal cavity the fast will break and a qadha will have to be kept. (Tahtaawi Alaa Maraaqil Falaah, pg. 672)
islamqa.org/hanafi/darulihsan/76642