Yes, they are if you are on a low fat, high carb diet. Try to think porridge for breakfast or flapjacks. Not a sports drinks made for professional athletes, you just won't use the energy up.
An average gel is designed to give a 'normal' man of 160-175 lbs a blood sugar of between 120 and 140 mg/dl in 30 minutes, they recommend 2 to 3 gels an hour. The artificial and highly processed sugars react fast and hard, some of the drinks and gels use un-natural sugars (not found in nature), your body will treat these as a toxin, and the poor liver will get the double whammy of fructose and poison at the same time. Thus some people get side cramps from them.
Note I said normal people, now the same gel will spike a pre-diabetic to 200mg/dl and it does not come down slowly because it was designed for sustained energy. If the person just does one gel, they may get away with it, as it drops to 140 by the second hour. This is boasted of on one sports gel site...personally I'd vomit all over the floor if my BG went that high and I was trying to exercise.
As a general rule, my training partner Chris (who is diabetic) applys a couple of rules that seem to work for most diabetics as well as pre-diabetics:
You don't need extra fuel for less than an hour and a half aerobic exercise, just water.
After that point take food (drinks or bars or real food) and electrolytes (plain water or water plus electrolyte (no sugars or sweeteners) seperately. Drink regularly.
Since she changed to that system, she no longer gets cramps or vomits when doing long distance events.
