system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: toddlers and their sleep to energy ratio

I just….. I just don’t understand. How do toddlers/young children just wake up rudely and abruptly early, ready to run a triathlon whilst doing a speech and debate event. I feel like I need an IV of caffeine.

I can get the same amount of sleep and still be dragging ass. Is it just because as adults we are plagued with stress/responsibilities, etc?
gpt
IIRC up until age three or so the human body is experiencing a phase of accelerating growth. Cells are proliferating at a rate they never will match again— basically for a year or so, the lil wee bastards are Wolverine. 

It takes a lot of energy to power that, and you’re seeing it in all its manic glory. And don’t forget they crash hard, too.