Glycogen sparing and fat as aerobic fuel question? (1 Viewer)

[stazi]

Hey I've got two questions that I'm unsure of for my exam tomorrow.
First up,
Glycogen sparing works in order to use up a mix of fats (predominantly fats) rather than carbohydrates during early stages of aerobic activity. Wouldn't this be more tiring as fat is more intensive to metabolise.

Also why is Fat the source of fuel in endurance events?

 

[mr_speedy]

glycogen sparing can only be used by well trained athlets, and it is so towards the end of the race, the athlete can use his/her glycogen stores, as you can get more energy out of it.

fat is the main source of fuel because we have more of it, as glycogen tends to run out in about 1 hour.