Put one's oar in to reach sporting podium, they say (6)
I believe the answer is:
'put one's oar in' is the definition.
(to put one's oar in is to meddle or interfere)
'reach sporting podium they say' is the wordplay.
'reach sporting podium' becomes 'medal' (medal can mean to win a medal).
'they say' shows a homophone (sound like).
'medal' sounds like 'MEDDLE'.
'to' acts as a link.
(Other definitions for meddle that I've seen before include "Stick one's oar in" , "Mess with" , "Intrude, interfere" , "Interfere in people's affairs" , "Interfere in other's business" .)