How much to be considered tension?

[hello99]

Is it inevitable that no matter what we play, as long as there is a certain amount of intensity, there will be tension?

According to my teacher, he says that to be totally efficient with the use of the forearm muscles, it should be not warm by the end of practice no matter how long or how intense. Thats a litmus test to whether you are totally relaxed or not.

Usually I get a mild warm feeling at my forearms after practice. Sometimes it aches while playing, and I try to minimize it. When playing simpler pieces I do not usually get that ache. (I don't get tension on moonlight movement 3) but anything beyond that, (like revolutionary), I get (not ache), but warmness most of the time. And my teacher requires it to be totally semi-cold, (not warm). [not exactly icy cold, but just not warm].

Does warmth in forearm = tension?

It's only recently when I've took notice about the warmth in my forearms. i don't know if it affects sound but I seem like I am on a compulsory conquest to eliminate all tension.