system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why do children and teens grow in spurts or bursts, rather than continuously?
gpt
Hormones. 


Growth Hormone is released in cycles, you get bursts of it during sleep, so kids growing up overnight is actually kind of true. 


Growth hormone secretion is also increased by a number of other factors, most notably from testosterone and estrogen, which are increased during puberty. Other causes of increased growth hormone would be eating (insulin and glucagon both increase growth hormone), and exercise.


But like someone else already said: these things are occurring pretty consistently (that growth hormone increase is occurring every night), so the 'bursts' we see are probably just our own perception when we see that someone's grown an inch and we hadn't realized it.