ACE and hematocrit: Table 1 reports sample’s descriptive data. NT and HT groups did not differ significantly in terms of age, BMI and working experience, as well as altitude of workplace. Regarding anti-hypertensive therapy of HT participants: n = 4 were treated with Angiotensin II receptor blockers (ARBs); n = 2 with combinations of angiotensin II receptor blockers and calcium antagonist; n = 2 with calcium antagonist (CA); n = 1 with Angiotensin-Converting Enzyme inhibitor (ACE inhibitors).