PD2i Analysis of Heart Rate Variability in Competitive Sports

Inclusion Criteria: * Age \>18 years, as determined by birth date given on participation form. * Actively involved in competitive athletics * Able to give informed consent Exclusion Criteria: * Any known prior autonomic dysfunction * History of seizures or taking anti-seizure medication * Known learning disability or attention deficit disorder * Chronic heart conditions such as arrhythmias or valvular disease * History of diabetes mellitus * Taking any prescription stimulants such as Ritalin, Focalin, etc. * Use of any performance-enhancing drugs * Any deviation from normal found on the pre-participation physical exam such as the presence of a murmur or hypertension.