At the recent Ikeda-Sensei seminar, my mate Jeff asked Ikeda: Do you get tired after a day of treating patients- and what do you do about it?
The answer: I sleep. Whatever job you do, you're eventually going to end up knackered at some point..
The one thing that I tell any TCM student who asks for general advice is: never refuse to treat someone because you feel less than 100%- if you do that, you'll never treat anyone.. (obviously, don't treat if you're s**tfaced.. People have tried, it's never pretty.)
I find that it's very useful to do some exercise in general, and Qi Gong in particular (Zhu Ga Shaolin Qi Gong (low horse stance and working IMO on the Yang Wei Mai and Dai Mai) seems to fit me well- if I do a 'soft' Qigong it doesn't seem as powerful)- but I think that it's almost more important to watch your posture and tension during the treatment itself.. Particularly in the hands- too much tension, especially kinking up the fingers, seems to be one of the worst habits I developed... If you squeeze the tiger's tail too hard, he will turn around and bite you.
What I try and do is make lots of things into Qi Gongs- synchronise the breath with the patient while needling, breathe into the Hara while pulling up the perineal muscles (to increase intra-abdominal compression and build Qi), soften the Hara for reinforcing and harden for reducing... Apply your Qi Gong to your movement at all times in clinic.. etc. etc.
Ikeda also mentioned, after making a few more jokes at poor old Jeff's expense (in a good-hearted manner), that what you are lacking if you are exhausting yourself by treating is a sense of empathy, or pure love. He made pains to emphasise the 'pure' part, I know this is an area that gets people into trouble...
The "Metta" or 'loving kindness' practiced in Vipassana seems to help also.. And another mate of mine reckons that doing the Wing Chun forms while retaining needles affects how the patient feels as well..
Probably only 1.6 cents' worth, I'll do better next time..
Diagnosis is Treatment; Treatment is Diagnosis.