Hi James,
Although we are different as Type 1 diabetics, a lot of things remain the same as normo's. I lift weights and also take part in longer exercise sessions, e.g. football, cricket, cycling. I find that my body reacts to various products the same way it would a non-diabetic. E.g. I take protein shakes after lifting weights, I drink lucozade sport as part of my pre-match preparation and during matches. As long as you use insulin to balance the carbs you take on, you can use most products for the use they are intended.
Obviously, there needs to be a degree of dose adjustment around exercise. And I change my dose the same amount regardless of the carbohydrate I'm taking on board. So whether it's biscuits, banana, Lucozade Sport, chocolate, or whatever else, I use the carbs to keep me going, with a reduced amount of insulin. The protein shakes after exercise supplement my meal as usual and I inject the relevent amount of insulin to go with the carbs.
Hope that helps,
Give me a shout if you have any more questions.
Sam.