This article shows the result of survey carried on cardio-vascular system functions in men constantly living in Aral Sea Area. Has been stated that the affect of central system on cordial rhythm dominates on autonomous one in men who were indigenous residents of Karakalpakstan. In both age groups (20-39 and 40-50 years old) has been notable a sufficient adaptation to environment during the hot period of year. This is normal functional possibilities of organism and homeostasis reacted by control system at moderate tenseness.