Gymnastic exercise gives a person a buzz (5)
I believe the answer is:
rings
I believe this clue is a double definition.
'gymnastic exercise' is the first definition.
(rings are gymnastic apparatus)
'gives a person a buzz' is the second definition.
(to give someone a buzz is to ring them on a phone)
(Other definitions for rings that I've seen before include "Marks that are made round" , "Bands for fingers" , "Spaces used for boxing" , "that may circle planet (not ours)" , "jewellery" .)