Hypertension, Hypertension (HTN)
Conditions
Keywords
Dietary Nitrate, Beetroot Extract, Aerobic Exercise, Nitric Oxide, Older Adults, Blood Pressure
Brief summary
The goal of this clinical trial is to learn about the acute effects of beetroot extract in older women with high blood pressure. The main questions it aims to answer are: Does beetroot extract affect blood pressure during exercise? Does it change oxygen levels in the muscles? Participants will take a beetroot supplement and perform an aerobic exercise session to check how their bodies respond.
Detailed description
Note: Although registered as Single Group/Open Label for data entry purposes, this study is strictly double-blind and randomized regarding the order of interventions (crossover design). Hypertension is a major risk factor for cardiovascular disease in older adults. Dietary nitrate, found in beetroot extract, has been shown to improve vascular health and exercise tolerance. However, its specific effects on older women with hypertension during exercise require further investigation. This clinical trial aims to analyze the acute impact of beetroot extract supplementation on cardiovascular and metabolic parameters. Specifically, the study will measure blood pressure responses, oxidative stress markers, and muscle oxygen saturation (assessed via NIRS) in hypertensive older women submitted to a single session of aerobic exercise. The goal is to determine if nitrate supplementation can attenuate the cardiovascular stress of exercise and improve muscle oxygenation in this population.
Interventions
DIETARY_SUPPLEMENTBeetroot Extract (Nitrate-rich)
Participants will ingest 2 capsules of a standardized beetroot extract (Berkeley Life Nitric Oxide Foundation). Each dose provides approximately 314 mg of dietary nitrate.
DIETARY_SUPPLEMENTPlacebo
Capsules identical in appearance, color, and size to the experimental supplement, but containing an inert substance (starch). This intervention is used to maintain the double-blind design of the study.
BEHAVIORALExercise
Participants will perform a single aerobic exercise session on a treadmill. The protocol consists of a 7-minute warm-up followed by 30 minutes of continuous exercise at an intensity corresponding to 60-80% of maximum heart rate (HRmax), estimated using Tanaka's formula (208 - 0.7 \* age). Rate of Perceived Exertion (RPE) will be monitored periodically using the Borg scale (6-20).
OTHERRest (Control Condition)
Participants will remain seated for 30 minutes (matching the exercise session duration). During this time, a researcher will administer a Food Frequency Questionnaire (FFQ) in an interview format. This activity serves to assess dietary habits and simulates a routine, low-exertion daily activity (similar to a conversation), acting as a time-matched control for the exercise session.
Sponsors
São Paulo State University
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
BASIC_SCIENCE
Masking
NONE
Eligibility
Sex/Gender
FEMALE
Age
60 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
* Female sex: Older women aged between 60 and 70 years. * Physical capability: Absence of health conditions that could compromise performance in the required physical exercise tests.
Exclusion criteria
* Smoking: Current smokers. * Alcohol use: History of alcohol abuse or excessive alcohol consumption. * Cardiovascular Disease: Diagnosis of cardiovascular diseases (other than the primary condition of hypertension).
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Systolic and Diastolic Blood Pressure | Baseline (Rest), during intervention (at 10 and 20 minutes), immediately post-intervention (at 30 minutes), and 10 minutes post-intervention recovery. | Assessed using a validated automatic or semi-automatic device. Results measured in millimeters of mercury (mmHg). |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Muscle Oxygen Saturation | Continuously recorded during the 30-minute exercise session. | Assessed via Near-Infrared Spectroscopy (NIRS) placed on the vastus lateralis muscle. Measured in percentage (%). |
| Oxidative Stress Markers (SOD, CAT, GPx, MDA) | Baseline (Pre-intervention) and immediately post-intervention (after exercise or rest). | Analysis of Superoxide Dismutase (SOD), Catalase (CAT), Glutathione Peroxidase (GPx), and Malondialdehyde (MDA) levels in blood plasma. Results measured in nanomoles per minute per gram of protein (nmol/min/g). |
Countries
Brazil
Contacts
CONTACTAnderson S Zago, Professor
CONTACTLucas K Carvalho, Master's student
Outcome results
None listed