Inclusion Criteria:  To be between 18- 30 years old. To volunteer to participate in the study Not engaging in regular exercise. Not to have a chronical disease or history of chronical disease. Not to take any medication.  Exclusion Criteria:  Being outside of the range of 18- 30 years old. To have any kind of medical condition that disturbs the autonomic nervous system To have a chronical disease To have a regular medication To have/had head injury, intracranial bleeding or increased intracranial pressure.