There are no such studies conducted that can summarize what is the best time to take T, if you take via IM route its going to distribute with the same flow no matter what time of the day you are going to administer it. Hmm I just read 'Right before the gym' that left me in hysterics lol.
Prework out stuff works quicker than T right before gym if you wanna see the quick action in 20 mins.
Cheers Mate