someone define gels?
BTW, glycogen doesn't deplete after 45 minutes, not even close. Theres a shitload of glycogen in the body, most people just hit the wall after about 45 minutes because the body is converting from the use of mostly glycogen -> FFAs/lipids/stored fat.
It does this because fat is more in supply to the body then glucose in the long run, but the body can't mobilize/use fat as fast as you need it unless your working mostly aerobically as opposed to anaerobically. If you are running 45 minutes chances are your pretty much going solid aerobically.
Most people tend to be good at one or the other, they can go 30 minutes hardcore then hit a wall and have to stop meaning they handle glucose well (most often occurs in sprinters/any anaerobic sport)
While others can't sprint/20 minute bouts of running or less but they don't ever really hit the "wall" at about 40 minutes, they could keep going all day.
Both can be trained through aerobic or anaerobic exercise.
But I still don't know wtf gels are?
(BTW, the liver holds about 100G~ carbohydrates at any given time, while the muscles can hold between 800g-2000+g, if they didn't then people would become fatasses when carb loading, but the carbohydrates go somewhere when you deplete your muscle glycogen) Your body can access more carbohydrates easily though since protein, fats, and carbohydrates can all be converted into glucose.
If you were referring to liver glycogen becoming depleted, then yes, but then your body can just tap into muscle glycogen or use gluconeogenesis and make more carbohydrates outta the precious muscles
