Central Arterial Hemodynamics and Resistance Training

Study Overview
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Brief Summary
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Resistance exercise training is one of the popular exercise modes that has been drawn the public's attention. However, existing evidence showed high-intensity resistance exercise training-induced negative adaptation on vascular function and blood pressure responses. Upper-body resistance exercise training is more likely to induced arterial stiffening, which has been shown to be gender-dependent. It is still unknown whether age also plays a role. We like to test the hypothesis that high-intensity upper body resistance exercise may lead to a higher increase of arterial stiffness, central blood pressure, and hemodynamic parameters in younger adults than older adults. We also hypothesize high intensity resistance training could contribute to greater central hemodynamic responses and muscle stiffness than the control; the change of muscle stiffness correlates with the change of hemodynamic parameters. Collectively, study 1 in this project is aimed to recruit 40 apparently healthy young (20-35yrs) and middle-aged to older adults (50-75yrs) into this study followed by upper-body or lower-body high-intensity exercise (80% 1 repetition maximum, 10 reps, 4 sets) by a randomized order. Blood draw, central blood pressure, hemodynamics will be performed and obtained at pre-, immediately-post, 20min, 40mins, and 60 mins post-exercise. Study 2 is aimed to investigate the effects of 8-week whole-body resistance exercise training followed by a 4-week detraining on above-measured variables in order to determine the long-term effects on resistance training. We will employee state-of-art ultrafast ultrasound to obtain muscle stiffness and carotid local pulse wave velocity. Endothelin-1 and catecholamines will also be measured to discover its underlying mechanisms on such stiffening effects induced by high-intensity resistance exercise.

Official Title
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Central Blood Pressure and Arterial Hemodynamic Responses to High-intensity Resistance Exercise Training - the Application of Ultrafast Ultrasound Analysis

Conditions
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Hypertension, Cardiovascular Risk Factor

Intervention / Treatment
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* Other: Resistance exercise training


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Healthy middle-aged to older adults Exclusion Criteria: (1)BMI≧27, (2) Smoking habits for more than six months in the past, (3) Hypertension (blood pressure>140/90 mmHg), (4) Personal diabetes history (fasting blood sugar >126 mg /dL), heart disease, or other cardiovascular diseases, (5) bone damage, (6) regular use of supplements or vitamins

Ages Eligible for Study
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Minimum Age: 50 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Health Services Research
Allocation: Randomized
Intervention Model: Factorial Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Exercise training<br>The participants will undergo 8 weeks of whole-body resistance exercise training followed by a 4-week detraining. The central hemodynamic and muscle stiffness variables will be measured pre, post-training, and post-detraining. | Other: Resistance exercise training<br>* Eight weeks whole-body resistance exercise training (80%1 repetition maximal, 3 sessions per week) followed by a 4-week detraining intervention<br>|
| No Intervention: Sedentary control<br>The participants will undergo 12 weeks of intervention without exercise training. The central hemodynamic and muscle stiffness variables will be measured pre, 8th, and 12th week. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Central blood pressure | Carotid blood pressure obtained by using tonometer | Pre, 8th and 12th week | 
| Muscle shear wave velocity | Shear wave velocity measured by using ultrafast ultrasound | Pre, 8th and 12th week | 
| Arterial pulse wave velocity | Pulse wave velocity measured by using a commercialized vascular monitor. | Pre, 8th and 12th week | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Vascular related biomarkers | Catecholamines, endothelin-1 | Pre, 8th and 12th week | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Exercise, Ultrafast ultrasound