Why do cats always run around at night?
1. Cat's living habits
Everyone knows the nickname "night owl," right? Actually, those who know a little about cats' habits should know that although cats are active during the day, they prefer to be active at night.
Especially for cats that have had enough rest during the day, their energy levels are even higher at night. To burn off this energy, cats will entertain themselves by finding interesting things to do. It's similar to dogs destroying things at home. Cats also need a certain amount of exercise, but because they don't need to go outside, they exhibit this kind of neurotic behavior to burn off energy. 
2. The cat was bitten by fleas.
Another reason cats run around like this is that they may have fleas. Flea bites can make cats very uncomfortable and distressed, which can lead to sudden, manic behavior.
3. An intruder appears in the home.
If dogs have a very keen sense of smell, then cats have an almost supernatural one. Cats might exhibit this behavior if they smell other animals in the house.
For example, if other animals wander into the house or the cat sees someone else's animal wandering outside, these things can trigger this behavior in cats. Cats have a very strong sense of territory, and if someone dares to suddenly enter their territory, the consequences can be severe.
