Hi
I'm a rower and so is constantly in the gym ! It sounds like your over compensating way to much hence the bs spike afterwards. If your going to stick with the lucozade then you definitely need to be drinking less. Before you start exercise I normally go for a blood sugar of around 10-13 depending on what type I'm doing !
It's going to be trail and error to see how much you actually need.
Sometimes actually switching your pump of for a bit works, so if I'm doing a very long workout then I do tend to switch all basal of 30/40mins before but obviously this has to be done very carefully, I.e bloody sugars every 15 mins to make sure your not to high !
Hope this helps
Also it depends what energy drink your having as you shouldn't be having any with caffeine in them and a lot do without telling you !