I remember back in an old school that I practiced in, I had asked the teacher if it was ok to sweat during the form and he said that sometimes it’s good to sweat and other times it’s not. He then went on to talk about how it’s ok to sweat if you are trying to rid your body of toxins, etc but not normally. From then, I always wondered if it’s ok to sweat during the form b/c I usually do as I tend to practice low postures and to train the gongfu aspect of the art.

After searching around some forums and such for this, I ran across a thread that discussed how CMC talked about the same things to his students in America. I then ran across an entry from StormMountain that went:

I think the point he was trying to make was that one should not use overly stiff muscular force. However, we must also consider that at a certain point Master Chen no longer taught the combative aspects of Tai Chi, just the chi gung aspects. I assume that the no sweating rule was his effort to get people to not just move slow, but RELAX DEEPLY.However, if you are doing Yang style with DEEP POSTURES you will sweat!!!
source

Reading this shedding a little light on the topic for me b/c then I realized that a lot of the material from the teacher I inquired also came from CMC. Perhaps it all comes down to the reason for training in taiji. If you want to train for health and spirituality, then there is no reason to sweat, but if you’re working on training in low postures and other gongfu aspects of the art, then perhaps sweating is ok.

Usually, for myself, the first time I do the set, I don’t sweat b/c I’m usually performing the set at a higher stance and then not until about the third repetition of the set do I begin to sweat b/c that’s usually when I’m working on maintain low postures and all the lovely biomechanics that go along with it. For me, I like to sweat and I know that in time when my legs get stronger and my hips open up more, the sweating will start to lessen, but for the time being, I’m a sweating monkey hehe