Table 3.

Cardiovascular variability during active and passive squat-stand maneuvers in young subjects

Variables	Active		Passive
	0.1 Hz	0.05 Hz	0.1 Hz	0.05 Hz
SBP, mmHg	133±13	128±11	138±17	128±11†
DBP, mmHg	62±12	62±10	68±13	64±10
HR, beats/min	86±9	79±9†	84±9	77±8†
RF, Hz	0.35±0.7	0.32±0.06	0.40±0.09	0.37±0.09
ETCO2, mmHg	39±3	39±3	39±3	39±3
SBP-SP, mmHg2	223±90	343±248†	75±59*	113±74*
RR-SP, ms2	4,224±2,872	16,933±6,236†	1813±2130	6227±3608*†
Gain, ms/mmHg	4.3±1.5	6.8±2.4†	4.4±2.5	7.0±2.5†
Gain-P, ms/mmHg	4.1±1.8	7.7±2.6†	4.5±2.5	8.3±4.2†
Phase, rads	−0.9±0.6	−0.6±0.3	−0.9±0.5	−0.9±0.5
Phase-P, rads	−1.0±0.6	−0.5±0.2†	−1.1±0.5	−0.8±0.3*†
Coherence	0.70±0.06	0.77±0.08	0.73±0.17	0.69±0.09
Coherence-P	0.99±0.01	0.99±0.01	0.96±0.09	0.96±0.05

Values are means ± SD (n = 10). Transfer function gain, phase, and coherence were estimated in the frequency range from 0.078 to 0.125 Hz and from 0.031 to 0.078 Hz. Gain-P, Phase-P and Coherence-P, estimated at the peak coherence.

^*P < 0.05, comparisons between active and passive maneuvers at the same frequency,

^†P < 0.05 comparisons between the frequencies under the same conditions.