An interventional study of Nitrate group and Placebo group in Healthy, Menopause and Hypertension, sponsored by University of Vienna. Recruiting at 1 site in Austria. Open to female participants aged 45 Years to 65 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-06-05.
Sponsored by University of Vienna · Not applicable, Interventional, and Prevention
The purpose of this clinical study in women after menopause is to investigate whether the daily intake of nitrate from beetroot juice over 12 weeks enhances the positive effect of exercise training on vascular function, blood pressure and physical performance.
The risk of cardiovascular diseases (CVD) increases with advancing age and women are particularly affected. In women, the decline in the sex hormone oestrogen in the blood circulation with menopause contributes to impaired vascular function and an increased CVD risk; in part through increased inflammatory processes, oxidative stress, and a reduced body's own production of nitric oxide (NO). NO is a signaling molecule that is important for vascular function. Endurance-based exercise training is a key lifestyle strategy to prevent CVD. However, studies indicate that exercise is less effective in terms of its health-promoting adaptations in women after menopause as compared with men of similar age.
This study investigates the effect of exercise training in combination with the intake of nitrate-rich beetroot juice on functions of the cardiovascular system. Nitrate is a nitrogen compound that is found naturally in plant foods (e.g. beetroot juice) and is converted to NO in the human body. Results of previous studies indicate vasodilatory, blood pressure-lowering and performance-enhancing effects as well as positive influences on inflammatory processes and oxidative stress following nitrate intake. The hypothesis is that nitrate intake concomitant to training promotes training adaptations and further improves vascular function, blood pressure and physical performance compared to training without nitrate intake.
For the study, 54 untrained postmenopausal women (with the ages between 45 and 65 years) will be recruited and randomly allocated into two groups. Both groups will undergo 12 weeks of endurance-based exercise training. One group will receive nitrate-rich beetroot juice, and the other nitrate-depleted beetroot juice (as placebo). Vascular function, blood pressure, maximum oxygen uptake, and blood biomarkers for nitrate metabolism, inflammation status and oxidative stress will be examined.
The anticipated study results will provide new insights into whether nitrate as a 'training adjunct' improves health-promoting training adaptations in women after menopause. The overall aim is to improve the cardiovascular health and performance of middle-aged women and reduce their increased CVD risk.
Wider research context:
Advancing age is a major risk factor for cardiovascular diseases (CVD). In women, the decline in the sex hormone oestrogen with menopause contributes to impaired vascular function and an increased CVD risk, in part via a reduced bioavailability of the endothelium-derived signaling molecule nitric oxide (NO), chronic low-grade inflammation and increased oxidative stress. Aerobic (or endurance) exercise training is a key lifestyle strategy to prevent CVD. However, data indicate that exercise is less effective for improving cardiovascular health in postmenopausal women as compared with men of similar age. Oestrogen treatment may restore vascular training adaptations but is associated with health risks. The main objective of this research is to examine whether dietary nitrate as a nutritional 'adjuvant' to regular exercise could be an innovative lifestyle intervention to favorably modulate vascular training adaptations and health in midlife women. This research expands upon findings by the investigators and others showing that inorganic nitrate from vegetables exerts benefits on physical function and cardiovascular health by increasing NO availability through the nitrate-nitrite-NO pathway and by attenuating inflammation and oxidative stress.
Objectives and hypotheses:
The investigators propose a clinical study to examine whether the daily consumption of nitrate-rich beetroot juice concomitant with aerobic exercise training improves vascular function, blood pressure, and cardiovascular fitness in postmenopausal women more effectively as compared with nitrate-depleted beetroot juice consumption (as placebo). The hypothesis is that the increased nitrate intake favorably modulates the systemic inflammatory and oxidative stress status and promotes cardiovascular health-related training outcomes.
Methods:
This study will involve a prospective, randomized, placebo-controlled parallel-group design. 54 untrained postmenopausal women (45-65 years) will be recruited and randomized into two groups. Both groups will undergo 12 weeks of endurance-based exercise training. The training will consist of a supervised training program that meets contemporary guidelines on aerobic physical activity. One group will receive nitrate-rich beetroot juice (containing \~400 mg nitrate, based on available evidence on the physiological and ergogenic benefits of nitrate), and the other nitrate-depleted beetroot juice (placebo), on the background of a low-nitrate diet and an otherwise unaltered lifestyle. 42 participants (21 per group) will be required to complete the study, based on power/sample size calculations with the forearm blood flow response to acetylcholine as primary endpoint. Secondary endpoints and additional measures will include 24 h-ambulatory blood pressure, maximal oxygen uptake, and blood inflammation and oxidative stress biomarkers.
Originality and innovation:
It is anticipated that this work will provide important new evidence on the efficacy of dietary nitrate to improve the training responsiveness, vascular function, and cardiovascular health in women after menopause. The objective of such a combined nutritional-training approach is to promote, preserve or restore physiological function and delay or possibly prevent the transition to functional limitations and CVD.
Research funding and cooperation arrangements:
This clinical research is funded by the Austrian Science Fund (FWF) (grant DOI 10.55776/KLP1075624). It is based on close collaborations between the University of Vienna and the Medical University of Vienna (both Austria), with the Department of Clinical Pharmacology at the Medical University of Vienna as the clinical trial center and Prof. M.D. Michael Wolzt as the coordinating physician of the trial center. The sponsor is the University of Vienna, as represented by the Principal Investigator Dr. Oliver Neubauer, Priv.-Doz. (Department of Nutritional Sciences, University of Vienna). Further national collaborations involve the groups of Prof. M.D. Daniel König, Prof. Karl-Heinz Wagner (both University of Vienna), and Prof. Viktoria Weber (University for Continuing Education Krems, Austria). International collaborations include Dr. Catherine P. Bondonno, Prof. Jonathan M. Hodgson (both Edith Cowan University), Prof. Richard J. Woodman (Flinders University) (all Australia), Prof. Karsten Krüger (Justus Liebig University of Giessen, Germany), and Prof. Jason D. Allen (University of Virginia, USA).
6,114 studies on the registry are indexed under Hypertension; 912 are open to participants now.
This study's planned enrollment of 54 is below the median of 100 across 4,575 interventional studies indexed under Hypertension.
Browse Hypertension studies →University of Vienna is the lead sponsor of 49 studies on the registry; 16 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Periods have stopped for good: usually no period for 12 months in a row without another medical reason, sometimes confirmed by a blood test (FSH).
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
A blood test of average blood sugar over the past two to three months, given as a percentage or in mmol/mol. 6.5% (48 mmol/mol) or more is the usual threshold for diabetes, normally confirmed by a second test.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
Postmenopausal
Periods have stopped for good: usually no period for 12 months in a row without another medical reason, sometimes confirmed by a blood test (FSH).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
GFR and eGFR (kidney filtering)
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HbA1c
A blood test of average blood sugar over the past two to three months, given as a percentage or in mmol/mol. 6.5% (48 mmol/mol) or more is the usual threshold for diabetes, normally confirmed by a second test.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ECG (electrocardiogram)
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Daily consumption of 70 mL nitrate-rich beetroot juice concomitant with 12 weeks of exercise training
Dietary Supplement: Nitrate group
Daily consumption of 70 mL nitrate-depleted beetroot juice (placebo) concomitant with 12 weeks of exercise training
Dietary Supplement: Placebo group
Daily consumption of 70 mL beetroot juice containing \~400 mg nitrate over an intervention period of 12 weeks concomitant to exercise training, either 3 hours pre-exercise on training days or with breakfast on non-training days.
Also known as: Nitrate-rich beetroot juice
Daily consumption of 70 mL nitrate-depleted beetroot juice (placebo) over an intervention period of 12 weeks concomitant to exercise training, either 3 hours pre-exercise on training days or with breakfast on non-training days.
Also known as: Nitrate-depleted beetroot juice
Forearm blood flow (FBF) response to acetylcholine (FBFACh)
Endothelial-dependent microvascular function
Time frame: Change from baseline FBFACh to after the 12-week intervention period
24-hour ambulatory systolic blood pressure
Ambulatory blood pressure monitoring
Time frame: Change from baseline 24 hour-ambulatory systolic blood pressure to after the 12-week intervention period
Maximal oxygen uptake (V̇O2 max)
Cardiorespiratory fitness: V̇O2 max
Time frame: Change from baseline V̇O2 max to after the 12-week intervention period
FBF response to glyceryltrinitrate (FBFGTN)
Endothelial-independent microvascular function
Time frame: Change from baseline FBFGTN to after the 12-week intervention period
Clinic blood pressure
Clinic blood pressure monitoring
Time frame: Change from baseline clinic blood pressure to after the 12-week intervention period
Plasma and saliva nitrate and nitrite
Nitrate metabolism: biomarker for nitrate bioavailability and functioning of the enterosalivary nitrate-nitrite-nitric oxide (NO) pathway
Time frame: Change from baseline plasma and saliva nitrate and nitrite to after the 12-week intervention period
Serum hsCRP
Systemic inflammation status: serum high-sensitive C-reactive protein
Time frame: Change from baseline hsCRP to after the 12-week intervention period
Plan to share: Yes — For long-time preservation and sharing of the research data, it is planned to use the PHAIDRA digital repository of the University of Vienna (https://phaidra.univie.ac.at). This repository enables the permanent secure storage of digital assists including open access publications and research data necessary to reproduce and to verify the results of the publications. For all publications and other data related to this research that will be made available, all of the individual participant data collected during the trial will be de-identified.
Supporting information: Study protocol, Statistical analysis plan, Informed consent form, Clinical study report
Time frame: The plan is to publish the findings in scientific journals and to present them at scientific meetings and to the public after the study is completed.
Access criteria: Supporting the Open Access Policy of the University of Vienna, the PHAIDRA repository enables public access of the research data necessary to reproduce and to verify the results of publications from this research. The Austrian Science Fund (FWF) that funds this clinical research also requires to make peer-reviewed publications based on the results openly accessible on the Internet.
Started Mar 2025 (actual). Primary completion is estimated for Mar 2027, 24 months after the start.
Of 1,403 non-industry interventional studies with no phase under Hypertension, half reached primary completion within 23 months of starting (the median), counting those still running; a quarter within 10 and three quarters within 41. This study's planned 24 months is close to that.
Counting every sponsor, half of 1,498 studies reached it within 23 months; a quarter within 10 and three quarters within 41.
How these figures are worked out, and which studies are left out of them.
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
Contact study teamGet an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
Studies of the drug tested here: Nitrates
University of Vienna