Like some exercises (7)
I believe the answer is:
aerobic
'like some exercises' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for aerobic that I've seen before include "Exercises to enhance respiratory efficiency" , "Like exercise that aids the intake of oxygen" , "Exercise that enhances circulation" , "needing oxygen" , "(Of exercises) related to increasing oxygen in blood" .)