@Gojo saturo first is the environment and situation the environment is already obvious their body is stronger thanks to mana and the time they are in second is situation most of times when they get damage they are in a fight if you noticed when having any fist fights with someone you would have noticed you feel less pain it's because your body starts to produce adrenaline which dulls your senses this mostly happens when animals in a deadly situation but for humans our body can just start producing it in a fight because of perhaps anger or thrill