I keep candy bars in my bag that I bring with me to the dojo. My sensei is aware of the diabetes, and very supportive-both of my training, and of my taking care of myself while i train.
We will be training for several hours on Saturday, and i will certainly try eating some nuts or other protein before we get started to see if that helps any.
The waking up in the middle of the night is the *most* frustrating part. shaking and a cold sweat at 2 in the morning twice a week gets old quick. it has gotten a little less frequent lately, but i know i still have a lot to learn about managing it effectively, especially since there is so much variance in the intensity of the training from dojo trip to dojo trip.