An interventional study of Squatting Exercise and Stretching (Yoga) Exercise in Atherosclerosis Cardiovascular Disease, sponsored by Chinese University of Hong Kong. Recruiting at 1 site in Hong Kong. Open to participants aged 18 Years to 80 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-10-30.
Sponsored by Chinese University of Hong Kong · Not applicable, Interventional, and Prevention
Background:
Hypertension (HT) is the most common condition worldwide, predisposing to atherosclerotic disease. However, most HT patients have suboptimal BP control despite anti-HT medications. Isometric resistance exercise (IRE) (e.g. wall squat) may improve BP control, characterized by sustained muscle contraction with minimal change in muscle length and joint angle. Most randomized trials of IRE are short duration and their long-term effects on BP and atherosclerotic complications, particularly in the Chinese, remain unknown.
Study objectives:
(i) To evaluate the impact of IRE on atherogenesis surrogates (brachial flow-mediated dilation, FMD and carotid intima-media thickness IMT).
(ii) To evaluate the impact of IRE on mechanisms of atherogenesis improvement, inflammatory parameters, arterial wall stiffness and biochemical profiles.
Setting:
Randomized samples of 200 HT patients, aged >18years with systolic BP 135-160mHg while on no or stable anti-HT medications.
Design: Randomized controlled IRE trial - stratified randomization with randomization block size of 4.
Main outcome measures:
Expected results:
A group absolute difference in FMD of 1%, and in carotid IMT of 0.06mm between IRE intervention and control groups.
Implications: IRE as suggested will be beneficial to management of HT for atherosclerosis preventions.
Introduction
Hypertension (HT) is the most common condition worldwide predisposing to atherosclerotic diseases (stroke, heart attack and peripheral vascular disease), apart from other traditional risk factors [1-3]. However, most HT patients have suboptimal BP control despite anti-HT medications [4]. On this issue, aerobic and dynamic exercise are effective in BP-reduction, but HT-patients often have poor compliance with exercise, mainly because of requirement of additional time, skill training, venue and equipments [5-6]. Isometric resistance exercised (IRE) (e.g. wall squat) may improve BP control, characterized by sustained muscle contractions with minimal change in muscle length and joint angle. However, most randomized trials of IRE have short duration and their long-term effect on BP-reduction, mechanisms and atherosclerosis complications, particularly in the Chinese, remain unknown [7-11].
Much advance in noninvasive vessel-imaging has been witnessed in past few decades. Brachial flow-mediated dilation (FMD) and carotid intima-media thickness (IMT), have been advocated as surrogate markers for the documentation of early atherosclerosis and evaluation of preventive measures (12-20). Both brachial FMD and carotid IMT can now be measured accurately with high reproducibility, and have been related to cardiovascular outcomes. In clinical context, a 0.1mm increase in carotid IMT has been associated with 41% increase in stroke and 43% increase in acute myocardial infarction over a follow-up period of 2-7 years. [17] An 8% difference in carotid IMT was approximately similar to the kind of difference seen between diabetes and non-diabetes Chinese adults [21).
Aims and Hypotheses to be Tested
Systemic hypertension has been proven accelerating atherosclerotic process. To further test this initial hypothesis, this interventional substudy aims:
(i) To evaluate the impact of IRE on atherosclerotic surrogates (brachial FMD and carotid IMT).
(ii) To evaluate the impact of IRE on mechanisms of BP and atherogenesis reductions, including endothelial function FMD, carotid IMT and arterial wall stiffness (cfPWV), and inflammatory parameters.
3.1 The impact of Isometric resistance exercise (IRE) Intervention on brachial FMD and carotid IMT.
Subjects:
200 HT adults, aged >18 years with SBP 135-160mmHg on AMBP will be recruited. Those with incapacitating osteoarthritis of knee and secondary HT will be excluded.
3.2 Methods: These HT participants will be randomized to practise IRE (100 adults) 14 mins per session, (2 mins IRE x 4sets, 2 mins rest in between), 3 sessions per week, or usual standard care \& stretching (yoga) exercise (100 adults).
Week-0 \~ Health Examination, Randomization (IRE vs Yoga), Vascular Study (FMD \& IMT), Blood Test, and Arterial wall stiffness (cfPWV)
Week-13 \~ Compliance (adhenence) checking
Week-24 \~ Health Examination, vascular study (FMD \& IMT), blood tests, and arterial wall stiffness (cfPWV)
One Year \~ Compliance (adherence) checking, vascular study (FMD \& IMT), vessel wall stiffness, and blood Tests
Collection of health data:
Endothelial function, flow-mediated dilation (FMD) of the brachial artery and carotid IMT will be studied by using high resolution ultrasound.
(i) Endothelial function, (brachial flow-mediated dilation, FMD) will be studied by using high resolution ultrasound, as described previously. [12,22-24] In brief, the diameter of the brachial artery will be measured on B-mode ultrasound images, using a linear array transducer (HF L38) with a median frequency of 13-6MHz and a standard Sonosite (MicroMaxx) system. Forearm tourniquet cuff placement will be applied to induce reactive hyperemia on deflation. Scans of brachial artery 10cm proximal to elbow will be acquired at rest, during reactive hyperemia (to induce flow-mediated endothelium-dependent dilation, FMD). FMD will be expressed as % of dilation from baseline vessel diameter normalized with vessel strain. Hyperemia is calculated as the % increase in blood flow after cuff deflation compared with baseline.
(ii) Carotid intima-media thickness (CIMT) measurement - B-mode ultrasound examinations will be performed using a 10-5 probe, with a 7.5 MHz scanning frequency linear array transducer. All carotid scans will be performed by a single operator after a predetermined, standardized scanning protocol for the right and left carotid arteries as described by Salonen and Salonen [16] and Touboul et al [19], using images of the far wall of the distal 10 mm of the common carotid arteries. All scans will be recorded on super-VHS videotape for subsequent off-line analysis for intima-media thickness (IMT), using a verified automatic edge-detecting and measurement software package as described previously. [19-24] The intra-observer variability of mean IMT is 0.003 to 0.011mm (CV 0.998%).
3.3 Outcomes
3.3.1 Primary outcomes: Vascular Parameters: Brachial FMD (%) and Carotid IMT (mm) at baseline, 24 weeks and 1 year.
3.3.2 Secondary outcomes: (i) Carotid femoral pulse wave velocity, cfPWV (mm/sec) at baseline and 24 weeks.
(ii) Other important traditional atherosclerosis risk factors: BMI (weight kg/ height m\^2), glucose (mmol/l), lipid profiles (mmol/l), HgbA1-C (%), creatinine (umol/L), haemoglobin (g/dl), hsCRP (mg/l), Fibrinogen (mg/dl) and IL-6 (pg/ml) at baseline, 24 weeks and 1 year.
3.3.3 Safety profiles (if any) including CVS event and hospitalization at 1 year,
4. Compliance with Declaration of Helsinki. The design, methodology and conduction of project are in compliance with Declaration of Helsinki.
5. Data processing and analysis:
(5.1) Power Calculation: The SPSS version 28 was used to calculate the sample size for FMD and carotid IMT. Data from our previous studies on Chinese adults in Hong Kong reported FMD was in 6-8% +/- 1.3%, and carotid IMT was 0.55-0.68mm +/- 0.1mm. On the assumption of post IRE brachial FMD will improve to 6.7-8.7 +/- 1.4%, and carotid IMT will reduce to 0.51-0.61mm +/- 0.11mm, recruitment of 200 Chinese adults (100 in each group) will be adequately powered (85%) to detect a group difference in brachial FMD of 1.2% and in carotid IMT of 0.06mm (12%), at 1 year between the two treatment groups.
(5.2). Data Analysis: Statistical Analysis System SPSS version 28 will be used for all statistical analyses. Descriptive methods will be used to describe characteristics of cardiovascular risks. The primary endpoints are AMBP, brachial FMD and carotid IMT; serological inflammatory biomarkers (Neutrophil/ monocyte ratio and Platelet), hsCRP, fibrinogen and IL-6 are secondary endpoints. Students' T-tests will be used to detect the group differences in brachial FMD and carotid IMT. Multivariable linear and logistic regressions will be used to calculate the risk magnitude by IRE vs usual care and stretching exercise interventions, and to control potential confounders such as traditional cardiovascular risk factors.
478 studies on the registry are indexed under Essential Hypertension; 74 are open to participants now.
This study's planned enrollment of 200 is above the median of 144 across 406 interventional studies indexed under Essential Hypertension.
Browse Essential Hypertension studies →Chinese University of Hong Kong is the lead sponsor of 1,454 studies on the registry; 474 are open to participants now.
Of its 6 completed or terminated interventional studies of FDA-regulated products, 0 (0%) have results posted.
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The criteria were revised on the registry on Oct 30, 2026. See what changed
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
A more linear thigh-leg squatting angle is allowed in initial 2 weeks, but aiming at 90 degree thigh-leg angle after 4 weeks.
Other: Squatting Exercise
A liberal leg stretching excerise will be practised
Other: Stretching (Yoga) Exercise
14 minutes per session (2 mins x 4 sets, 2 mins rest in between, 3 session per week)
2 mins x 4 sets, 2 mins rest in between, 3 sessions per week
The Impact of Isometric Resistance Exercise on Accelerated Atherosclerosis in Hypertension
Changes in Brachial FMD (%)
Time frame: Baseline, 24 weeks and 1 year
The Impact of Isometric Resistance Exercise on Accelerated Atherosclerosis in Hypertension
Changes in Carotid IMT (mm)
Time frame: Baseline, 24 weeks and 1 year
The Impact of Isometric Resistance Exercise on Accelerated Atherosclerosis in Hypertension
Changes in Carotid femoral pulse wave velocity, cfPWV (mm/sec)
Time frame: Baseline and 24 weeks
The Impact of Isometric Resistance Exercise on Accelerated Atherosclerosis in Hypertension
Other important traditional atherosclerosis risk factors: Changes in BMI (weight kg/ height m\^2)
Time frame: Baseline, 24 weeks and 1 year
The Impact of Isometric Resistance Exercise on Accelerated Atherosclerosis in Hypertension
Changes in Fasting Glucose (mmol/l)
Time frame: Baseline, 24 weeks and 1 year
The Impact of Isometric Resistance Exercise on Accelerated Atherosclerosis in Hypertension
Changes in Fasting Lipid profiles (mmol/l) 1. Changes in high density lipoprotein cholesterol (HDL-C) (mmol/l) 2. Changes in low density lipoprotein cholesterol (LDL-C) (mmol/l) 3. Changes in Triglyceride (TG) (mmol/l)
Time frame: Baseline, 24 weeks and 1 year
The Impact of Isometric Resistance Exercise on Accelerated Atherosclerosis in Hypertension
HgbA1-C (%)
Time frame: Baseline, 24 weeks and 1 year
The Impact of Isometric Resistance Exercise on Accelerated Atherosclerosis in Hypertension
Creatinine (umol/L)
Time frame: Baseline, 24 weeks and 1 year
The Impact of Isometric Resistance Exercise on Accelerated Atherosclerosis in Hypertension
Haemoglobin (g/dl)
Time frame: Baseline, 24 weeks and 1 year
The Impact of Isometric Resistance Exercise on Accelerated Atherosclerosis in Hypertension
hsCRP (mg/l)
Time frame: Baseline, 24 weeks and 1 year
The Impact of Isometric Resistance Exercise on Accelerated Atherosclerosis in Hypertension
Fibrinogen (mg/dl)
Time frame: Baseline, 24 weeks and 1 year
The Impact of Isometric Resistance Exercise on Accelerated Atherosclerosis in Hypertension
IL-6 (pg/ml)
Time frame: Baseline, 24 weeks and 1 year
Plan to share: Yes — There is a plan to make IPD and related data dictionaries available. All IPD that underline results in a publication.
Supporting information: Study protocol, Statistical analysis plan, Informed consent form
Time frame: These materials will be available and shared on reasonable requests to Prof KS Woo from January 2025 till 30 December 2027
Access criteria: These materials will be available and shared on reasonable requests to Prof KS Woo from January 2025 till 30 December 2027 (kamsangwoo@cuhk.edu.hk/ crec@cuhk.edu.hk)
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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