This is a very good video clip about the importance of self regulating, "going slowly" in TRE.
He talks about if you've been frozen/ dissociated, through TRE, you may move into a fight/ flight state which will unfreeze your muscles and sometimes free emotions. It is very important to be careful to not get overwhelmed because this may just freeze you up again.
So the motto is always go slow. E.g only do some exercises; only tremor for 1- 5- 10 min; only tremor once a week or every other day.It will be different for every person, thus having a facilitator will help you notice these states and changes in a safe way.

Another good link from this doctor where he highlights his life changing journey through TRE.