Relationship between blood pressure and cerebral blood flow during supine cycling: influence of aging.

The cerebral pressure-flow relationship can be quantified as a high-pass filter, where slow oscillations are buffered (<0.20 Hz) and faster oscillations are passed through relatively unimpeded. During moderate intensity exercise, previous studies have reported paradoxical transfer function analysis (TFA) findings (altered phase or intact gain).

Methodological comparison of active- and passive-driven oscillations in blood pressure; implications for the assessment of cerebral pressure-flow relationships.

We examined the between-day reproducibility of active (squat-stand maneuvers)- and passive [oscillatory lower-body negative pressure (OLBNP) maneuvers]-driven oscillations in blood pressure. These relationships were examined in both younger (n = 10; 25 ± 3 yr) and older (n = 9; 66 ± 4 yr) adults. Each testing protocol incorporated rest (5 min), followed by driven maneuvers at 0.