Glycogen IS glucose, just chains of it; makes for efficient transport. Once it enters into the muscle-cells, it's taken apart into glucose to generate ATP in the kreb's cycle. All glucose-storage in muscle cells themselves is glycogen as well. The liver can only store about 200-300 calories anyway, not a significant amount.

It really doesn't matter what you drink, that really only affects the digestion and absorption rate. Once Cytomax, Gatorades, sugar-water, etc. crosses the intestinal walls into the bloodstream, they're all the exact same stuff, glucose and some fructose. Although maltodextrin is absorbed fairly fast and its amylose-amylopectin structure is very similar to glycogen.

Due to the rates of activity, 500-800 calories/hr, there's no way you can keep up with consuming calories of any kind, simple or complex. So it's best not to consume solutions of more than 200-250cal/hr since that can lead to cramping and slow absorption of water. Your blood-sugar will always be a little low while exercising, so there's absolutely no insulin being pumped in like if you drank Cytomax or Gatorade while sitting on the couch watching a game. If anything, you've got the insulin analog, glucagon being pumped in to make your adipose tissues convert fat into glucose for energy. Also triggers your liver to dump its supply of glycogen in. Adrenaline and epinephrine, which is responsible for the dopamine-effect of the runner's high, also has a similar fat-conversion effect. Perfectly normal metabolism.

Note that there's absolute nothing you can drink or eat to actually improve your performance above your current physiological state. If your VO2-max is a certain value, and you weigh a certain amount of Kg, and you have a certain power-output at LT, you're going to be doing a certain ride at a certain max speed/time based upon your fitness. Nothing you can drink/eat will improve that on any certain day. However, you can hurt your performance and do worse than that by not having proper nutrition and hydration. The worse thing you can do is to drink/eat nothing resulting in a bonk. Speeds and times suffer tremendously when you're crawling along at 9-10 mph, desperately scanning the ground for half-eaten candy-bars and other carbs to eat. And your body will be tearing apart good muscle for fuel, negating your workouts for the past week or so...