Beliefs and Expectation Effects on Blood Pressure Following Isometric Exercise in Inactive Adults

Status: Recruiting
Location: See location...
Intervention Type: Behavioral
Study Type: Interventional
Study Phase: Not Applicable
SUMMARY

This study investigates how isometric exercise training (IET) affects blood pressure in physically inactive adults. Isometric exercise involves sustained muscle contractions without movement-for example, pushing against a fixed object. Previous research has shown that IET may help reduce blood pressure, but the mechanisms involved are not fully understood. The purpose of this study is to assess both the immediate (acute) and long-term (chronic) effects of IET on cardiovascular outcomes. Participants will complete a series of lab-based exercise sessions over several weeks. In these sessions, they will perform repeated bouts of isometric leg extensions while seated on an exercise machine designed to measure muscle force. Throughout the study, researchers will monitor participants' blood pressure, heart rate, and muscle activity. Acute responses-such as post-exercise hypotension (a short-term drop in blood pressure)-will be measured immediately after exercise. Chronic changes, such as resting blood pressure improvements, will be evaluated across the training period. Additional measurements will include heart rate variability (HRV), which gives insight into autonomic nervous system activity, and electromyography (EMG), which tracks muscle fatigue and activation patterns. These data will help explore potential mechanisms behind the cardiovascular benefits of IET. By examining how repeated sessions of isometric exercise influence blood pressure and related physiological responses, this research may support the use of IET as a non-pharmacological strategy for managing or preventing hypertension in physically inactive individuals.

Eligibility
Participation Requirements
Sex: All
Minimum Age: 18
Maximum Age: 55
Healthy Volunteers: t
View:

• Age 18 years or older

• Self-reported physically inactive or insufficiently active (not meeting current physical activity guidelines)

• Not currently engaged in structured resistance or isometric exercise training

• Able to attend lab sessions over a 4-week period

• Provides written informed consent

Locations
Other Locations
United Kingdom
Canterbury Christ Church University
RECRUITING
Canterbury
Contact Information
Primary
Sean Machak
s.machak2125@canterbury.ac.uk
+447864658805
Backup
Philip Hurst
philip.hurst@canterbury.ac.uk
+44 (0)1227 927700
Time Frame
Start Date: 2025-04-21
Estimated Completion Date: 2025-09
Participants
Target number of participants: 36
Treatments
Experimental: Neutral Information + Isometric Exercise
Participants in this group complete repeated isometric exercise training sessions. Prior to training, they receive a neutral informational presentation about isometric exercise, which does not mention blood pressure or cardiovascular benefits. The exercise consists of bilateral isometric leg extensions on a dynamometer. Cardiovascular and neuromuscular outcomes, including blood pressure, heart rate variability, and muscle fatigue, are monitored throughout the intervention period.
Experimental: Expectation-Enhancing Info + Isometric Exercise
Participants in this group complete repeated isometric exercise training sessions. Prior to training, they receive an expectation-enhancing informational presentation that emphasizes the effectiveness of isometric exercise as a non-pharmacological intervention for reducing blood pressure. The exercise consists of bilateral isometric leg extensions on a dynamometer. Blood pressure, heart rate variability, and muscle activity are assessed to determine physiological responses to the intervention.
No_intervention: No-Intervention Control
Participants in this group do not receive any intervention or educational presentation. They attend study visits for assessment purposes only. Measurements include resting blood pressure, heart rate variability, and muscle activity, allowing for comparison with the intervention groups to evaluate the effects of isometric exercise training.
Sponsors
Leads: Canterbury Christ Church University

This content was sourced from clinicaltrials.gov