Effect of Exercise on Endothelial Injury in Hypertensive Patients

Summary

Introduction: Endothelial dysfunction precedes atherosclerosis being evidenced in patients with hypertension. Increasing physical activity levels and/or physical exercise are part of the recommendations of antihypertensive therapy. However, the effects of oscillations and/or increase the systemic blood pressure induced by exercise session on endothelial function has not been studied.

Objective: To evaluate the effect of aerobic exercise, resistance exercise and combined exercise on endothelial injury levels in patients with hypertension.

Methodology: Hypertensive (n = 51) and healthy subjects (n = 30) (30-59 years old) will perform at random 40 minutes of aerobic exercise (50-60% of heart rate reserve) or 40 minutes of resistance exercise (4 x 12 repetitions of exercises for lower limbs, 60-70% of one repetition maximum and 60-90 second interval) or 40 minutes of combined exercise (20 minutes of resistance exercise and 20 minutes of aerobic exercise, in that order). Blood will be collected 10 minutes before, 10 and 60 minutes after intervention for the quantification of endothelial microparticles (MPE) circulating (induced endothelial lesion) and endothelial progenitor cells (EPC) circulating (endothelial recovery capacity) by flow cytometry. Ambulatory blood pressure monitoring (ABPM) will be held before and after the intervention. Ultrasonography is used to measure the flow-mediated dilation of the brachial artery 10 minutes before, 10, 30 and 60 minutes after the intervention.

Statistics: generalized estimating equation (GEE) for repeated measurements and Person correlation, being significant p \< 0.05.

It is expected to show results to ensure cardiovascular protection in patients with hypertension caused by different types of exercise and consequent endothelial injury and release induced regenerative factors. Knowledge of the magnitude of injury and endothelial recovery provided by different types of exercise can contribute scientifically to health professionals aimed at prescribing exercise with a vascular protective vision in patients with hypertension.

Conditions

• Hypertension
• Healthy

Interventions

OTHER

AEROBIC

The aerobic exercise session (AE) will consist of 40 minutes on an exercise bike in heart rate (HR) corresponding to 60% of heart rate reserve (moderate intensity) acquired by the formula of Karvonen: \[(HR max - HR rest) x desired intensity\] + HR rest; monitored through heart monitor brand Polar and perceived exertion rating (Borg scale of 6-20). It will be added to the exercise time 5-7 minutes to proper heating.

OTHER

RESISTANCE

The resistance exercise session (RE) will last 40 minutes and will consist in carrying out 4 sets of 12 repetitions with interval of 90 seconds between sets and exercises. The weight will be adjusted to 60 % of a maximum repetition (1-RM) (moderate intensity) in four exercise for the lower limbs: leg press, knee extension, bend knees and plantar flexion (calf). The cadence of each series will be controlled by electronic metronome and performed with 2 seconds in the concentric phase and 2 seconds in the eccentric phase. It will be added to the exercise time 5-7 minutes for the warming to be held in the leg press exercise (one set of 15 to 20 repetitions with 1/3 load set for the session).

OTHER

COMBINED

The combined exercise session (resistance and aerobic) will last 40 minutes. The exercise resistance phase of the combined session will consist of 20 minutes, according to the resistance exercise described above. Immediately after resistance exercise, patients will perform aerobic exercise (AE) for 20 minutes. In order to keep the equivalent time among the three interventions (aerobic exercise, resistance and combined) will be performed two series (2 x 12 repetitions) in each resistance exercise.

Sponsors & Collaborators

• Instituto de Cardiologia do Rio Grande do Sul

  lead OTHER

Study Design

Allocation

RANDOMIZED

Purpose

SUPPORTIVE_CARE

Masking

SINGLE

Model

FACTORIAL

Eligibility

Min Age

30 Years

Max Age

59 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2016-01-31

Primary Completion

2019-12-31

Completion

2020-01-31