It's a rush of adrenaline to the brain caused by an intense feeling of pressure. By wanting to do well, we subconsciously make better choices when under these high pressure situations. Some people will panic and make mistakes caused by nerves whereas some people , like you, will do better :) as a previous answer said, it is called zone zero.we tend to do it as a survival instinct, it puts things into a clearer view.
We do not know exactly why this happens.
Sometimes it seems everything is in slow motion, and in baseball the ball suddenly appears to be larger and much slower so it is easy to hit.
It seems your mind is not controlling your body, your body is in charge.
Some people call it the zone. Its mainly caused by a rush of adrenaline and other chemical reactions in your body.
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