Because fat is more important than muscle in fighting, because its fluidity is very important for full combustion in our body, and compared with muscle, it is relatively compact, and muscle itself is a symbol of strength. Like fat, it may rebound in battle, giving opponents a sense of confusion. But relatively speaking, it depends on everyone's physique. Like fat, it is less elastic and may be more resistant to beating, while muscle is real and it can only be attacked by you.