Combined Exercise Session, Combined Strength Training, Control Session (CON), Dynamic Strength Exercise Session, Dynamic Strength Training, Isometric Strength Exercise Session, Isometric Strength Training
Conditions
Keywords
Ambulatory Blood Pressure Monitoring, Resistence training, Isometric exercise, Post-Exercise hypotension, Endothelial Function
Brief summary
Dynamic strength training (DST) is widely recognized for promoting neuromuscular adaptations such as increased strength and hypertrophy. It is currently endorsed by treatment and prevention guidelines for systemic arterial hypertension (SAH) due to its significant effect on lowering blood pressure (BP). However, when comparing BP reduction values, isometric strength training (IST) stands out with greater magnitudes of BP reduction, although without the neuromuscular adaptations seen in DST. Given their similarities, a combination of these strategies through combined strength training (CST) is possible but has not yet been evaluated. The researchers hypothesized that CST may have an additive effect compared with DST and IST alone in reducing ambulatory BP. Therefore, the objective of the present thesis was to evaluate and compare the effects of CST, DST, and IST on regulatory variables of ambulatory BP in medicated middle-aged hypertensive patients. This thesis is structured in two parts: (1) a crossover study with medicated middle-aged hypertensive patients to identify autonomic, endothelial, and vascular responses related to ambulatory BP after a single session of CST, DST, and IST; and (2) a randomized clinical trial to assess the chronic effects of CST, DST, and IST on regulatory variables of ambulatory BP in medicated middle-aged hypertensive patients.
Detailed description
"This thesis is structured in two sequential stages: A randomized crossover trial involving medicated middle-aged hypertensive patients to identify autonomic, endothelial, and vascular responses on ambulatory blood pressure following a single session of Combined Strength Training (CST), Dynamic Strength Training (DST), and Isometric Strength Training (IST), compared to a control session. A randomized controlled trial to assess the chronic effects (8 weeks) of CST and DST on the regulatory variables of ambulatory blood pressure in medicated middle-aged hypertensive patients, compared to a non-exercising control group."
Interventions
Participants in this group undergo two phases. Phase 1: A single acute exercise session consisting of 8 resistance exercises (3 sets of 11 repetitions with a 10-second isometric hold at the end of each set; 1s concentric/2s eccentric phases). Phase 2: An 8-week chronic intervention period, performing the same combined protocol 3 times a week, with intensity progressing from 50% to 65% of 1RM.
Participants in this group go through two phases. Phase 1: A single acute exercise session consisting of 8 resistance exercises (3 sets of 14 repetitions, 1 second concentric phase and 2 seconds eccentric phase, 30 seconds of rest between sets and 90 seconds between exercises) at 50% of 1RM. Phase 2: An 8-week chronic intervention period, performing the same dynamic resistance protocol 3 times a week, with intensity progressing from 50% to 65% of 1RM.
Participants in this group undergo a single acute exercise session consisting of 8 resistance exercises performed isometrically. The protocol includes 3 sets per exercise, with each set consisting of a 10-second static contraction at 50% of 1RM, with 30 seconds of rest between sets and 90 seconds between exercises
Participants in this group undergo two phases. Phase 1: A single acute control session consisting of quiet rest in a seated position for the same duration as the exercise sessions. Phase 2: An 8-week follow-up period where participants maintain their usual daily activities and pharmacological treatment without any structured exercise program.
Sponsors
Study design
Masking description
While it was not possible to mask the participants and the exercise instructors due to the nature of the training sessions, a clear separation was maintained between the team supervising the exercises and the team responsible for data collection and analysis. Specifically, the outcomes assessors responsible for the Ambulatory Blood Pressure Monitoring (ABPM) and Flow-Mediated Dilation (FMD) measurements were completely blinded to the participants' group allocation and had no involvement in the training protocols.
Intervention model description
"The study follows a sequential design divided into two distinct phases. In Phase 1 (Acute), a randomized crossover design is employed where all participants undergo four experimental sessions (Control, Dynamic Strength, Isometric Strength, and Combined Exercise) in a randomized order, with a minimum washout period of 48 to 72 hours between sessions to evaluate 24-hour post-exercise hypotension. In Phase 2 (Chronic), participants are then randomized into three parallel groups (Control, Dynamic Strength Training, and Combined Strength Training) for an 8-week intervention period. This phase aims to evaluate long-term cardiovascular adaptations, including 24-hour ambulatory blood pressure and endothelial function. Data collection for both phases has been completed."
Eligibility
Inclusion criteria
Clinical diagnosis of stage 1 or stage 2 hypertension, according to current guidelines. Sedentary lifestyle (no participation in structured exercise training for at least 6 months). Age between 18 and 60 years. Stable antihypertensive pharmacological treatment for at least 4 weeks before enrollment. Ability to perform resistance exercise.
Exclusion criteria
Symptomatic cardiovascular disease. Heart failure. Unstable angina. Uncontrolled diabetes mellitus (HbA1c \> 8%). Renal insufficiency. Musculoskeletal disorders or physical limitations that contraindicate resistance exercise. Changes in antihypertensive medication within the 4 weeks prior to enrollment or during the study protocol. Current smoking. Excessive alcohol consumption.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| 24-hour Ambulatory Blood Pressure (Systolic, Diastolic, and Mean) | Baseline and 8 weeks | Average systolic blood pressure measured over a 24-hour period using an automated ambulatory monitor (ABPM). This measure assesses the chronic effect of the 8-week training protocols compared to baseline. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Acute 24-hour Ambulatory Blood Pressure (Systolic, Diastolic, and Mean) | 24 hours post-intervention | Average systolic blood pressure measured over a 24-hour period following a single session of each intervention (Dynamic, Combined, Isometric, and Control) to evaluate post-exercise hypotension. This was conducted in a crossover design. |
| Acute Post-Exercise Blood Pressure Response | Baseline, 30 minutes, and 60 minutes post-exercise. | Systolic and diastolic blood pressure measured at rest (pre-intervention) and at 30 and 60 minutes following a single exercise session to evaluate the immediate post-exercise hypotension (PEH). |
| Vascular Endothelial Function - Chronic (Flow-Mediated Dilation) | Baseline and 8 weeks | Percentage of brachial artery dilation measured via high-resolution ultrasound to evaluate the chronic adaptations of vascular endothelial function after the 8-week intervention. |
| Vascular Endothelial Function - Acute Response (Flow-Mediated Dilation) | Baseline, 30 minutes, and 60 minutes post-exercise. | Acute changes in the percentage of brachial artery dilation following a single session of exercise. This measure evaluates the transient endothelial response at different time points. |
| Cardiac Autonomic Modulation - Chronic (Heart Rate Variability) | Baseline and 8 weeks. | Analysis of heart rate variability (HRV) parameters in both time and frequency domains (e.g., SDNN, RMSSD, LF, HF) to evaluate chronic adaptations in cardiac autonomic control after the 8-week intervention. |
| Cardiac Autonomic Modulation - Acute Response (Heart Rate Variability) | Baseline, 30 minutes, and 60 minutes post-exercise. | Acute changes in heart rate variability parameters following a single session of exercise. This evaluates the immediate autonomic recovery and sympathetic-vagal balance at different time points. |
| Office Blood Pressure Adaptation (Weekly Progression) | Baseline and weekly for 8 weeks. | Assessment of the progression of resting systolic and diastolic blood pressure measured before exercise sessions throughout the 8-week intervention to evaluate the time course of blood pressure adaptations. |
| Blood-based Biomarkers of Cardiovascular Health | Baseline and 8 weeks | Analysis of blood samples to evaluate biochemical markers related to cardiovascular health, such as markers of inflammation, oxidative stress, or nitric oxide bioavailability, to investigate the mechanisms underlying blood pressure changes. |
| Acute Blood-based Biomarkers Response | Baseline, 30 minutes, and 60 minutes post-exercise. | Analysis of blood samples to evaluate the acute response of biochemical markers related to cardiovascular and endothelial health (e.g., nitric oxide metabolites, inflammatory cytokines, or oxidative stress markers) following a single session of exercise. |
| Body Composition (Skinfold Thickness) | Baseline and 8 weeks | Assessment of body composition using skinfold thickness measurements to estimate body fat percentage and lean body mass. This measure monitors physical changes and ensures that any observed blood pressure adaptations are not solely due to changes in body fat or weight. |
Countries
Brazil