Evaluation of Two Isometric Exercises in the Reduction of the Blood Pressure in People With Resistant Hypertension

Evaluation of the Safety and Efficacy of Two Isometric Exercises in the Reduction of the Blood Pressure in People With Resistant Hypertension

Hypertension remains the main preventable cause of cardiovascular disease (CVD) and all-cause mortality, both in Europe and globally. Resistant hypertension, a severe phenotype of hypertension, is defined as a blood pressure (BP) that remains above the management goal despite using three different antihypertensive agents of different classes at the maximum or maximum tolerated dose, or controlled BP on four or more antihypertensive medications. Hypertension remains a poorly controlled risk factor on a global scale and the prevalence of resistant hypertension is also growing - it is now estimated to be around 10-20%.

At the moment, there is robust evidence establishing the antihypertensive effects of exercise. The acute reduction of BP after a single bout of exercise is known as post-exercise hypotension.

In recent years, the number of investigations into the benefits of isometric exercise in the treatment of hypertension has increased, due to its ease of access and potential for use. In a recently published meta-analysis, the authors pointed to isometric exercise as the most effective type of exercise in reducing systolic and diastolic BP.

Given the scarceness of data regarding the safety and efficacy of isometric exercise in individuals with resistant hypertension and since the acute response to exercise may help to identify people who respond to exercise as antihypertensive therapy, the objective of this study is to analyse the acute effect on BP levels of two different isometric exercises - isometric handgrip (IHG) and isometric wall squat (IWS), regarding safety and efficacy, in people with resistant hypertension.

The aim is to analyse if isometric exercises are safe in this population, through the assessment of BP during the execution of the exercises. Besides that, the comparison of IHG and IWS with the control session and between one and another, will help to understand which form of isometric exercise is most effective and has the longest lasting impact on reducing BP.

Each participant must complete an acclimatization session, in which the procedures will be explained, data will be collected and the intensity of IHG and IWS will be assessed. Subsequently, each participant must complete three randomly assigned experimental sessions: a non-exercise control session and two exercise sessions, in which they will follow the protocols currently used in the literature (IHG at 30% of Maximum Voluntary Contraction and IWS at 95% of peak Heart Rate).

Study Overview

• Status: Recruiting
• Conditions: Resistant Hypertension
• Intervention / Treatment: Other: Isometric exercise

• Study Type: Interventional
• Enrollment (Estimated): 15
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: José Lopes, Master; Phone Number: +351913101958; Email: up201410536@edu.fade.up.pt
• Study Contact Backup: Name: José Oliveira, PhD; Email: joliveira@fade.up.pt

Study Locations

• Portugal
  • Aveiro, Portugal
    • Recruiting
    • Local Health Unit of the Aveiro Region
    • Contact: Ana Rita Pereira, MD; Email: ARPereira3@ulsra.min-saude.pt

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Adults aged 40 to 75 years old, previously diagnosed with resistant hypertension, and on stable medication for at least 6 months.

Exclusion Criteria:

• People with secondary hypertension, heart failure, peripheral artery disease, atrial fibrillation, chronic obstructive pulmonary disease or renal failure; people with a cerebro-cardiovascular event in the previous 3 months; people with changes in pharmacological therapy in the previous 6 months; trained people (with regular participation (≥ 2x/week) in exercise training programs in the previous 3 months); people who have any contraindication to exercise; people with neurological and/ or orthopaedic conditions that will interfere with their participation in exercise, such as Parkinson's disease or knee osteoarthritis. Participants with low score (<6) on the MMAS-8 will also be excluded.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Single

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
No Intervention: Control Session; Each participant will remain in a seated position, resting, for 40 minutes.
Experimental: Isometric Handgrip Session; After remain in a seated position, resting, for 15 minutes, each participant will perform 4 repetitions of 2 minutes, alternating hands, maintaining the handgrip at a strength value of 30% of the maximal voluntary contraction (MVC) obtained in the initial test, with 1 minute of rest between each repetition. The exercise will be performed in a seated position. Participants will be encouraged to breathe normally and avoid the Valsalva maneuver.	Other: Isometric exercise; In each arm, participants will execute an isometric exercise, in which they will perform 4 repetitions of 2 minutes.
Experimental: Isometric Wall Squat Session; After remain in a seated position, resting, for 15 minutes, each participant will perform 4 repetitions of 2 minutes, maintaining the squat position with their back against the wall, with 2 minutes of rest (in a seated position) between each repetition. The knee joint angle will be defined using a fixed goniometer attached with Velcro to the thigh and leg. This angle corresponds to the knee position at 95% of the peak HR achieved during the initial incremental test. Participants will be encouraged to breathe normally and avoid the Valsalva maneuver.	Other: Isometric exercise; In each arm, participants will execute an isometric exercise, in which they will perform 4 repetitions of 2 minutes.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Ambulatory Blood Pressure Monitoring	Change from baseline values of Ambulatory Systolic and Dyastolic Blood Pressure Monitoring (in mmHg)	Blood Pressure (in mmHg) will be assessed 15 minutes after the intervention and then every 20 minutes after each intervention session (exercise sessions and control session) until 12 hours after session

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Office Blood Pressure	Systolic and Dyastolic blood pressure (in mmHg) will be measured using automatic oscillometric (change from baseline will be calculated)	Systolic and Dyastolic BP will be measured immediately before the intervention session, during the exercise sessions (at 30 seconds and 90 seconds of each repetition of the handgrip and the wall squat) and 15 minutes after each intervention session
Adverse Events	Number and severity of adverse events that occur during or after exercise	Adverse events that occur during the intervention sessions, immediately after the intervention sessions or until 48 hours after the exercise sessions will be recorded

Collaborators and Investigators

• Sponsor: Universidade do Porto
• Collaborators: Aveiro University
• Investigators: Study Chair: Fernando Ribeiro, PhD, University of Aveiro; Study Chair: Linda Pescatello, PhD, University of Connecticut; Study Chair: Ana Rita Pereira, MD, Local Health Unit of the Aveiro Region

Study record dates

Study Major Dates

• Study Start (Actual): July 11, 2024
• Primary Completion (Estimated): September 1, 2024
• Study Completion (Estimated): September 1, 2024

Study Registration Dates

• First Submitted: July 10, 2024
• First Submitted That Met QC Criteria: July 17, 2024
• First Posted (Actual): July 23, 2024

Study Record Updates

• Last Update Posted (Actual): July 23, 2024
• Last Update Submitted That Met QC Criteria: July 17, 2024
• Last Verified: July 1, 2024

More Information

Terms related to this study

• Keywords: blood pressure; resistant hypertension; handgrip; isometric exercise; wall squat
• Additional Relevant MeSH Terms: Cardiovascular Diseases; Vascular Diseases; Hypertension
• Other Study ID Numbers: IHGvsIWSinResistantHT

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Individual participant data that underlie the results of this article, after deidentification.
• IPD Sharing Time Frame: IPD will be available after publication of the main results and up to five years.
• IPD Sharing Access Criteria: Individual participant data will be available for researchers who provide a methodologically sound proposal (e.g. individual participant meta-analysis).
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No