Ambulatory and Blood Pressure Variability Responses to Exercise in Normotensive and Hypertensive Women

All volunteers were submitted to a 24-hour Blood Pressure (BP) assessment by Ambulatorial Blood Pressure Monitoring (ABPM) before and after 10 weeks of combined exercise training, with a minimum of 48 hours after the last training session. A device was used associated with a diary of examination to self-report of activities of daily living (sleep, work, food) or any event that could interfere abnormally with BP or device measurements. The device was always placed 7am and the measurements were made every 15 minutes from 7h to 23h and every 30 minutes from 23h to 7h. The monitoring was considered valid when it happened for a period of 24 hours. The following results were evaluated: systolic blood pressure; diastolic blood pressure, mean blood pressure and heart rate in awake, sleep and 24-hour periods. Before the use ABPM during daily activities, resting blood pressure were measured using the same equipment after 15 min of rest in siting position.

Based on Ambulatorial Blood Pressure data, were calculated Blood Pressure Variability by: 24-hour standard deviation weighted by the time interval between consecutive readings; the mean diurnal and nocturnal deviations weighted for the duration of the daytime and nighttime interval; the average real variability weighted for the time interval between consecutive readings; the ambulatory arterial stiffness index calculated by the slope of the trend curve of the dispersion of pressure data; the morning surge that represents the dynamic daytime variation in morning pressure that tends to increase, being assessed from the point of least pressure during sleep in relation to the first two hours after waking; and nocturnal dipping, that represents the average percentage drop of sleep pressure in relation to wakefulness, and individuals with falls of 10% or more are considered dippers and below that are considered nom-dippers.

Heart Rate (HR) was recorded using a heart rate monitor in a beat-by-beat basis. HR was registered in a seat position for 20 min of rest. Prior to the HR Variability (HRV) analysis, the RR intervals (RRi) were visually inspected and filtered using a moving average filter. The HRV was analyzed in both time-, frequency- and nonlinear-domain. Being that for frequency-domain analysis, firstly the RRi series were interpolated at 4 Hz and then the signal linear trend component removal was performed using the smooth priors approach.

The salivary was collected after 12-hours fasting and the total antioxidant capacity was evaluated using the Ferric-Ability of Plasma (FRAP) methodology and calculated from the standard trolox curve. The activity of the enzyme superoxide dismutase (SOD) was determined based on the auto oxidation capacity of pyrogallol and catalase activity (CAT) by monitoring the consumption of hydrogen peroxide at 240 nm. Lipid peroxidation levels were determined by the TBARS method (thiobarbituric acid reactive substances), using as standard a curve of 1,1,3,3-tetraethoxypropane (TMP). The total protein concentration was obtained by the Bradford method (BRADFORD, 1976), using bovine serum albumin (BSA) as standard. The amounts of nitric oxide (NO) were estimated by the determination of total nitrite by the Griess colorimetric method.