30 MASL 520 MASL 1080 MASL p
Gender (M/F) 21/28 - - -
Age (year) 31 (26-51) - - -
Height (cm) 163 (158-170) - - -
Weight (kg) 62 (50-70) - - -
BMI (kg/m2) 23.0 (20.5-24.8) - - -
BT (°C) 36.5 (36.0-36.9) 36.5 (36.3-36.7) 36.4 (35.9-36.8) 0.87
SBP (mmHg) 113 (107-125) 111 (103-120)* 108 (100-116)*† 0.002
DBP (mmHg) 73 (68-79) 71 (68-77) 70 (66-75) 0.153
MABP (mmHg) 87 (82-92) 84 (81-90)* 83 (77-88)* 0.022
PP (mmHg) 42 (36-50) 39 (33-47)* 36 (33-42)* 0.014
HR (bpm) 74 (68-80) 69 (64-78)* 70 (64-77)* <0.001
mRRI (ms) 812 (747-885) 869 (768-937)* 863 (784-937)* <0.001
SDRR (ms) 33 (26-43) 39 (32-52)* 42 (32-58)* <0.001
CVRR (%) 4.2 (3.3-5.3) 4.9 (4.0-5.8)* 4.7 (3.9-6.2)*† 0.002
TP (ms2) 449 (247-761) 624 (367-1088)* 578 (409-1199)* <0.001
VLFP (ms2) 158 (70-260) 189 (126-316)* 174 (134-357)* 0.002
LFP (ms2) 110 (53-275) 189 (93-377)* 200 (92-318)* 0.018
HFP (ms2) 166 (68-300) 214 (101-389)* 196 (99-370)* 0.012
nVLFP (nu) 32.7 (23.8-46.4) 34.0 (21.8-43.8) 33.2 (24.2-48.2) 0.352
nLFP (nu) 30.2 (20.6-39.2) 31.0 (24.6-39.5) 28.0 (22.6-37.6) 0.6
nHFP (nu) 29.2 (22.2-47.0) 32.6 (21.4-43.4) 30.8 (21.4-45.2) 0.416
LHR 1.0 (0.5-1.5) 0.9 (0.6-1.6) 1.1 (0.5-1.8) 0.312
AT (°C) 31 (28-33) 30 (28-31) 30 (28-33) 0.205
RH (%) 58 (51-67) 62 (54-66) 55 (49-64)*† <0.001
Table 1: General characteristics of the study subjects, blood pressures, HRV measures and environmental conditions at 3 different altitudes (n=49). Values are median and interquartile range (25th to 75th percentile). *p<0.05 vs. 30 MASL; †p<0.05 vs. 520 MASL (Friedman repeated-measures analysis of variance on ranks with Student- Newman-Keuls test for post hoc pairwise comparisons). BMI: Body mass index; HR: Heart rate; RRI: RR intervals; mRRI: Mean RRI; SBP: Systolic blood pressure; DBP: Diastolic blood pressure; MABP: Mean arterial pressure; BT: Body temperature; bpm: Beats per minute; SDRR: Standard deviation of RRI; CVRR: Coefficient of variation of RRI; TP: Total power; VLFP: Very-low-frequency power; LFP: Low-frequency power; HFP: High-frequency power; nVLFP: Normalized VLFP; nLFP: Normalized LFP; nHFP: Normalized HFP; LHR: Low-/high-frequency power ratio; ms: Millisecond; nu: Normalized unit; AT: Ambient temperature; RH: Relative humidity.