Skip to main content
OpenTrials
Completed

NCT Number: NCT06985407

Grape Extract and Exercise Effects on Blood Pressure

Exercise and grape extract intake (i.e., polyphenol-rich product) can independently improve blood pressure and endothelial function in prehypertensive individuals. Nevertheless, their combined effects remain unexplored. Furthermore, since the biological pathways targeted by both interventions are similar, they could overlap and be amplified by one another, promoting additive or synergistic effects. Animal model studies have reported that a grape seed extract intake prevents exercise-induced oxidative stress, which could improve vascular dysfunction. Furthermore, as previously reported, a single dose of grape seed extract reduces blood pressure, peripheral vasoconstriction, and heart stress, enhancing O2 delivery during exercise in prehypertensive males. These effects may be partly due to endothelium-dependent vasodilation enhancement. Therefore, it is necessary to understand the potential impact of exercise and grape extract on blood pressure and vascular function in prehypertensive individuals.

Completed

Looking for future studies?

Notify Me

Key information

Conditions

Exercise Response Behavior Blood Pressure Monitoring, Ambulatory Motor Activity Polyphenol

Age range

25 year–70 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

UCLM

Toledo, Spain

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Sedentary individuals (<120 min·wk-1 of moderate-intensity activity assessed by 7-d IPAQ).
  • Aged 25-70 years and BMI 18-40 kg/m2.
  • Elevated BP (i.e., prehypertensive; systolic and diastolic BP between 120-139 and/or 80-89 mmHg, respectively)

Exclusion criteria

  • Weight instability (>5kg change in body mass over last 6 months)
  • Pregnant or lactating
  • Changes in physical activity over the last 3 months and planning on physical activity, or diet throughout the intervention.
  • Untreated cardiovascular or renal disease, peripheral vascular disease, hypertension, and any disease associated with exercise intolerance.
  • Currently taking dietary supplements that influence the cardiovascular response (e.g., polyphenols, omega-3 fatty acids, Magnesium, nitrates, L-arginine, red ginseng, natto, ginkgo, CoQ10) or used in the last month.
  • Current or recent use (within the past 6 months) of tobacco or nicotine-containing products, or illicit drugs.
  • Any medical condition or medication that could introduce bias into the study (e.g. neurological disorders)

Treatment and study plan

Grape extract (VinteraTM Premium OPC)

Dietary Supplement

Each condition will last 7 days for assessing both acute and chronic effects, and there will be a wash-out period of 7 days.

Control (placebo) group

Dietary Supplement

Each condition will last 7 days for assessing both acute and chronic effects, and there will be a wash-out period of 7 days.

Primary outcomes

  1. Postexercise systolic and diastolic blood pressure (mmHg)

    Time frame: Acute/chronic effects (0 and 7 days)

    Blood pressure will be measured in triplicated each 5 min during 40 minutes of supine rest.

  2. 24-hour ambulatory blood pressure following exercise (mmHg)

    Time frame: Acute/chronic effects (0 and 7 days)

    Ambulatory blood pressure will be assessed for 24 hours.

  3. Brachial flow-mediated dilation (%)

    Time frame: Acute/chronic effects (0 and 7 days)

    Flow-mediated dilation (FMD) in the brachial artery will be performed via two-dimensional (2-D)/Doppler ultrasound.

  4. Brachial blood flow (ml·min-1)

    Time frame: Acute/chronic effects (0 and 7 days)

    Brachial artery blood flow will be assessed via 2-D/Doppler ultrasound. Each blood flow recording period will be at least 4 min long.

Secondary outcomes

  1. Postexercise heart rate (bpm)

    Time frame: Acute/chronic effects (0 and 7 days)

    Post-exercise heart rate will be assessed for 40 minutes after completing the exercise.

  2. Plasma nitric oxide concentrations (μmol L-1)

    Time frame: Acute/chronic effects (0 and 7 days)

    Plasma nitric oxide concentrations will be determined using the enzymatic conversion of nitrate to nitrite by nitrate reductase (Thermoscientific; intra-and interassay CV 1.4%- 3.5%).

  3. Circulating endothelial biomarkers

    Time frame: Acute/chronic effects (0 and 7 days)

    Serum E-selectin concentration (ng mL-1); Serum P-selection concentration (ng mL-1); Serum Intracellular adhesion molecule 1 (ICAM-1) concentration (ng mL-1); Serum Vascular cell adhesion molecule 1 (VCAM-1) concentration (ng mL-1); Serum Tissue plasminogen activator (tPA) concentration (ng mL-1)

  4. Exercise total carbohydrate oxidation (g min-1)

    Time frame: Acute/chronic effects (0 and 7 days)

    Total whole-body carbohydrate rates were calculated using non-protein Péronnet and Massicotte's equations

  5. Exercise total fat oxidation (g min-1)

    Time frame: Acute/chronic effects (0 and 7 days)

    Total whole-body fat oxidation rates were calculated using non-protein Péronnet and Massicotte's equations

  6. Heart rate during exercise (bpm)

    Time frame: Acute/chronic effects (0 and 7 days)

    Heart rate will be continuously assessed during exercise

  7. Systolic and diastolic blood pressure during exercise (mmHg)

    Time frame: Acute/chronic effects (0 and 7 days)

    Blood pressure will be assessed during high intensity intervals.

  8. Plasma glucose concentrations (mg dL-1)

    Time frame: Acute/chronic effects (0 and 7 days)

    Serum concentrations of glycemia (in mg per dL) after 8-hour fasting

  9. Plasma insulin concentrations (µIU mL-1)

    Time frame: Acute/chronic effects (0 and 7 days)

    Serum concentrations of insulin after 8-hour fasting

Sponsors and collaborators

Lead sponsor

University of Castilla-La Mancha

Other

Registry information

Official study title

Acute and Chronic Effects of Grape Extract on Cardiovascular Response Following Exercise

Important dates

Study start
2026
Primary completion
2026
Study completion
2026
First posted
May 22, 2025
Registry last updated
May 6, 2026

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.