Beetroot Juice: a Natural Aid for Boosting the Health Benefits of Exercise in Post-menopausal Women?

Inclusion Criteria: * Self-reported biological female and postmenopausal (≥12 months of amenorrhea) * Aged 50-70 years * Body mass index (BMI) 25-39.9 kg/m² * No contraindications to exercise * Physically inactive (\<150 minutes/week of moderate-intensity activity) * Able to walk on a treadmill and ambulate without limitations * Adequate proficiency in Norwegian to complete questionnaires * Willingness and ability to comply with the study schedule and visits Exclusion Criteria: * Known allergy to nitrates or beetroot juice * Current smoker or use of nicotine/tobacco products * Resting blood pressure \<90/60 mmHg * Hypertension greater than stage II (≥160/100 mmHg, ESH criteria) * Use of prescription medications affecting heart rate (e.g., systemic β-adrenergic blockers) or nitrate availability (e.g., nitrates, proton pump inhibitors) * History of cardiovascular disease (e.g., myocardial infarction, stroke, ischemic heart disease, peripheral artery disease, valvular disease, or aortic aneurysm) * Symptoms suggestive of heart disease (e.g., chest pain or dyspnea) * Major metabolic disease (e.g., type 1 or type 2 diabetes) or thyroid disorders * Recent cancer diagnosis or treatment (within the past 5 years) * Significant orthopedic limitations or other contraindications to exercise * Diagnosed cognitive impairment * Planned travel or elective surgery that would interfere with adherence to the intervention * Psychological or social factors that may interfere with study participation * Residing beyond a reasonable distance from the study site (logistical constraints)