The symphativ nerve system (SNS) helps the human body to
adjust to different situations and to stress.
Hormons are used to push the bodys readiness in the situation of a fight.

The normal heartrate in a calm situation is about 60-80 beats per minute.

At 175 beats per minute the mind dives into a zone, where the human senses
like seeing, hearing and the cognitive abilities start to black out.

the tunnel.