Do players need to have full energy to train with max effect?

Do players need to have full energy to train with max effect? Or 90 and more energy is enough to train with max results?
The higher the energy, the better they train.
The higher the energy the more training points they get for stretching? Thought energy only effected how they play.
It would be nice for clarification on this...I have on occasion thought that I received inadequate/less than the norm TP when intensive training already tired players
It was confirmed on the forum a very long time ago, I'm sure if you dig deep and long enough you might find it
LOL that's a lot of help. Thanks Qball.
Its Saturday, I'm way to lazy to go digging for stuff lol.

If its of any help it was confirmed on the Touchdown Manager as well