system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: If it's better and less painful to stand up straight, then why do some people slouch all the time?
gpt
Who says it's less painful? Posture issues aren't just due to not feeling like standing up straight. Your muscles work together and against each other to hold your body in certain positions. Poor posture habits tend to cause a muscle at one end of a joint to be overly tight, while a muscle on the other end to be overly relaxed. In trying to correct that imbalance by simply standing up straight, you're forcing the muscle that's so used to being relaxed to try to counteract the muscle that has been straining, which leads to pain and discomfort, so the person will go back to whatever poor posture position they were in that isn't uncomfortable. Over time, it starts becoming unbearable to just stand up straight, and requires a significant concentrated effort and constantly reminding oneself to manually fix their posture, because their muscles will force them into the poor posture position.