Answered by Maulana Maruf Ahmed
I broke my fast deliberately as i was in a sport competition and was dehydrated what do i do as i feel guilty?
If someone breaks their fast due to an illness such as severe dehydration, only a Qada (single make-up fast) needs to performed. Kaffarah will not be binding. 
And only Allah knows best.
Written by Maulana Maruf Ahmed
Checked and approved by Mufti Mohammed Tosir Miah
Darul Ifta Birmingham
 (Ibn Abideen: Raddal-Muhtar, vol. 2 pg. 421, Dar al-Fikr, Beirut)
This answer was collected from DarulIftaBirmingham.co.uk, which is run under the supervision of Mufti Mohammed Tosir Miah from the United Kingdom.