The purpose of this study was to observe the magnitude and duration of the ambulatory blood pressure (BP) reduction following exercise and to identify the peak intervals of BP reduction throughout the 24-h diurnal period. Subjects were 25 normo-(N ‫؍‬ 116.7/ 78.2 ؎ 10.0/7.2 mm Hg) and 21 hypertensive (H ‫؍‬ 140.8/96.9 ؎ 13.9/9.6 mm Hg) adults. Twenty-four hour ambulatory blood pressures (SBP ‫؍‬ systolic and DBP ‫؍‬ diastolic) were recorded following exercise (E ‫؍‬ 50 min Ȱ 50% VO 2 max) and during a non-exercise control day (C). The 24-h pressures were compared between the E and C days for (1) duration and magnitude of the BP reduction following exercise, and for (2) the time of day for the diurnal patterns to exhibit reductions in BP. No BP differences were found for N between E and C days. Significant reductions in BP

Time of day (TOD) for exercise may influence blood pressure (BP) reduction in hypertension because of the diurnal variation of BP and the duration of BP reduction following a single bout of exercise. The purpose of this study was to observe the effects of TOD for exercise on ambulatory blood pressure reduction in dipping (n ¼ 5) and nondipping (n ¼ 9) hypertension (o10% drop in nighttime BP (BP night )). Hypotheses: (1) evening exercise (PM ex ) would exhibit a greater BP night reduction in NonDippers than Dippers, (2) morning exercise (AM ex ) would exhibit similar daytime BP (BP day ) reduction in Dippers and Non-Dippers, (3) AM ex would exhibit greater 24 h BP (BP 24 h ) reduction than PM ex in Dippers, and (4) AM ex and PM ex would exhibit similar BP 24 h reduction in NonDippers. BP responses to AM ex (0600-0800 h; 30 min at 50% VO 2peak ) and PM ex (1700-1900 h) were compared to each control day in a randomized design. Systolic (S) and diastolic (D) BP were averaged for BP 24 h , BP day , and BP night . A two-way ANOVA (dipping X time of exercise) using BP reduction with repeated measures were performed at Po0.05. Findings: (1) Non-Dippers respond to exercise despite of TOD for exercise, (2) PM ex exhibited a greater SBP night reduction in Non-Dippers than Dippers, (3) AM ex exhibited similar SBP day reductions in Dippers and Non-Dippers, and (4) AM ex and PM ex exhibited similar SBP 24 h reduction in Dippers and NonDippers. Dippers and Non-Dippers respond differently to TOD for exercise. The duration of the BP reduction persists up to 24 h after exercise.

Although the use of 24-h ambulatory blood pressure monitoring has been recommended in the study of blood pressure and exercise, consistent results have not been found for average 24-h systolic or diastolic blood pressures. Systolic load and diastolic load (the percentage of pressures >140/90 mm Hg during daytime hours and >120/80 mm Hg during sleep) have recently been identified as an important variable, but has had limited use with exercise. The purpose of this study was to compare the average systolic and diastolic pressures to systolic and diastolic loads from 24-h data recorded after a 50-min treadmill walk at 50% VO2max to data from a nonexercise control day. Subjects were 36 normotensive (116.9 +/- 10.7/77.0 +/- 8.9 mm Hg) and 25 hypertensive (141.0 +/- 13.7/96.6 +/- 9.0 mm Hg) adults. No significant differences were found for systolic and diastolic pressures or loads between the control and exercise days for normotensives. Even though no significant changes were found for any of the average systolic and diastolic pressures between the control and exercise days for the hypertensives, significant reductions were found in systolic load for 24-h (-25.7%), day (6 AM to 10 PM, -23.1%), work (6 AM to 5 PM, -22.9%), and leisure (5 PM to 10 PM, -26.7%) periods; and in diastolic load for the work (-22.5%) period. Thus, the measurement of systolic and diastolic load may be more sensitive than average systolic and diastolic blood pressures for the detection of 24-h ambulatory blood pressure changes with exercise in borderline hypertension.

The accuracy and reproducibility of ambulatory blood pressure monitoring used in intervention and treatment studies is essential to assure the desired health outcomes. The reproducibility of ambulatory variables in pharmacological studies has been reported, however, the reproducibility of ambulatory blood pressure variables associated with exercise has not been reported. Thus, the purpose of this study was to investigate the reproducibility of the postexercise ambulatory blood pressure in Stage I hypertensive adults. It was hypothesized that the reproducibility of the ambulatory blood pressure variables would not be different following two corresponding exercise and control treatments. A total of 18 Stage I hypertensive adults (142.173.15/ 91.671.80 mmHg) performed four randomized, 24 h AmBP monitoring sessions: two following a 50 min treadmill walk (50% VO 2 peak) and two on control days.Variables measured were: (1) average systolic and diastolic pressures for 24 h, daytime (06:00-22:00 h) and night time (22:00-06:00 h) and (2) systolic and diastolic load for the same time periods. Both a nonsignificant paired t-test and an excellent intraclass correlation were used to define reproducibility of the variables between the 1st and 2nd exercise trials and between the 1st and 2nd control trials. Reproducibility was found for all the control variables except for nighttime diastolic load. Reproducibility was found for all the systolic and diastolic exercise variables. Ambulatory blood pressure measurements, including average systolic and diastolic blood pressures and systolic and diastolic loads for 24 h, daytime and night time periods are reproducible following exercise.

Ambulatory blood pressure variables were consistently higher when the monitoring session began in the morning hours.