Can type 1 diabetics use GU products?
I use GU products. No different than other glucose-type products. You just need to account for your BG result and determine if you can take with or without insulin. The longer the run, the more likely you can take with little to no insulin. One gel pack is approx. 100 calories.
I use GU on my longer runs. I usually have to take one about every 45 minutes of running.
I try to start my run at about a 110 BS level. Buy keeping hydrated and using GU (I like the ones with Caffeine) I'll end a 1/2 marathon at about 130bs. And on a Marathon usually a bit higher in the 140-150 range.