AM vs PM Exercise Training

Study Overview
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Brief Summary
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The treatment of high blood pressure, or hypertension, is multifaceted and can include pharmacological therapies (i.e., medications) and lifestyle modifications such as physical activity. Chronotherapy, which describes timing of a treatment with the body's daily rhythms, has recently been used with hypertension medications and has been shown to be effective at lowering blood pressure and reducing the risk of cardiovascular disease events. Specifically, taking medications in the evening was shown to be more effective than morning medication routines. Little information is available about the effectiveness of chronotherapy combined with exercise (i.e., planned physical activity) interventions in older adults with hypertension. The purpose of this study is to examine how exercise training performed in the morning and early evening affects blood pressure and other measures of blood vessel health in postmenopausal females with hypertension.

Detailed Description
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Blood pressure has an internal rhythm associated with the 24-hr clock. Nocturnal blood pressure (BP) is a key contributor to cardiovascular health and may be improved by exercise. Moreover, the time of day of the exercise may be a key factor. This study aims to evaluate the effects of morning and evening exercise training on BP and other measures of vascular function in older females with hypertension.

Official Title
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Effects of AM vs. PM Exercise Training on Blood Pressure and Vascular Health in Postmenopausal Females With Hypertension

Conditions
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Hypertension

Intervention / Treatment
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* Behavioral: 6 weeks of exercise training (Pre-training)
* Behavioral: 6 weeks of exercise training (Post-training)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Systolic BP equal to or greater than 130 mmHg without BP medication or greater than 120 mmHg with medication and diastolic blood pressure equal to and greater than 80 mmHg 55-80 years old Post-menopausal female Able to walk without assistance Exclusion Criteria: Habitually physically active defined as 150 minutes of moderate-intensity or 75 minutes of vigorous-intensity aerobic physical activity per week Overt pulmonary disease/condition as follows: chronic bronchitis, chronic obstructive pulmonary disease, emphysema, or pulmonary hypertension Cardiometabolic disease/condition as follows: diabetes, heart failure, peripheral arterial disease, stroke, coronary artery disease, renal disease, secondary hypertension, chronic venous insufficiency or deep vein thrombosis within last 6 months Cancer within last 5 years Body mass index >39 kg/m2 Current smoking or vape Evening shift work uncontrolled thyroid disorder 2 or more falls in the last year Anemia within 3 months of enrollment Parkinson's disease Dementia Unstable angina Acute pulmonary embolus or infarction Acute myocarditis or pericarditis Acute aortic dissection

Ages Eligible for Study
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Minimum Age: 55 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Morning (AM)<br>Exercise starting before 10:01 AM | Behavioral: 6 weeks of exercise training (Pre-training)<br>* handgrip and treadmill walking 4 days per week<br>Behavioral: 6 weeks of exercise training (Post-training)<br>* handgrip and treadmill walking 4 days per week<br>|
| Experimental: Evening (PM)<br>Exercise starting after 3:59 PM | Behavioral: 6 weeks of exercise training (Pre-training)<br>* handgrip and treadmill walking 4 days per week<br>Behavioral: 6 weeks of exercise training (Post-training)<br>* handgrip and treadmill walking 4 days per week<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Nocturnal systolic blood pressure (BP) | Change in systolic nocturnal BP (Pre-training - Post-training) | 6 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Endothelial function | Change in flow mediated dilation of the brachial artery (Post-training - Pre-training) | 6 weeks | 
| Microvascular function | Change in rapid onset vasodilation of the popliteal artery | 6 weeks | 
| Ambulatory blood pressure | Change in systolic and diastolic BPs over a 24-hr period (Pre-training - Post-training) | 6 weeks | 
| Arterial stiffness | Change in carotid femoral pulse wave velocity (Pre-training - Post-training) | 6 weeks |