Effects of Beetroot Juice Supplementation on Exercise Blood Pressure and Metaboreflex Activation in Postmenopausal Women: A Randomized Placebo-Controlled Crossover Study

Menopause is characterized by a decline in estrogen levels, contributing to an exaggerated blood pressure (BP) response to exercise. This response is partly driven by alterations in the metaboreflex component of the exercise pressor reflex, a key regulator of BP during exercise. Currently, effective strategies to mitigate this response are lacking. Beetroot juice (BRJ) has potent BP-lowering effects at rest through estrogen-like mechanisms. However, whether BRJ can attenuate the BP response to exercise and improve metaboreflex function in post-menopause is unknown. Thus, this study investigated whether BRJ reduces the BP response to exercise and its effect on the metaboreflex in postmenopausal women. Eleven healthy normotensive postmenopausal women (57 ± 4 years, 9 ± 5 years since menopause, BMI: 23 ± 3 kg/m 2 , VO2max: 36 ± 7 mL/kg/min) were studied. Participants were randomized to consume 2 x 70 mL/day of BRJ and nitrate-depleted BRJ (placebo) for 4 days, separated by a washout period ≥ 7 days. Participants and investigators were blinded. Manual BP was recorded during a 10-minute resting period. Continuous beat-to-beat mean arterial BP (MAP) and heart rate (HR) were measured at rest and during isometric handgrip exercise (HG; 30% of maximal voluntary contraction), post-exercise ischemia (PEI; metaboreflex isolation), and a cold pressor test (CPT), included as a non-exercise sympathoexcitatory stressor. Data is presented as mean ± SD. There was no effect of BRJ intake on the peak BP response to HG (MAP: △ 16 ± 9 vs. 16 ± 6 mmHg, p = 0.66), PEI (MAP: △ 12 ± 7 vs. 11 ± 4 mmHg, p = 0.40) or CPT (MAP: △ 22 ± 11 vs 21 ± 12 mmHg, p = 0.25) compared to placebo. Similarly, no difference was observed for systolic BP, diastolic BP, and HR responses to HG, PEI, and CPT, p>0.05. Likewise, there were no differences observed in resting BP measures, p>0.05. These preliminary findings suggest that short-term supplementation of BRJ does not change the BP response to exercise or the metaboreflex component of the exercise pressor reflex in postmenopausal women. However, our cohort of women was very healthy and physically fit, which previous studies suggest could influence the effectiveness of BRJ. Thus, future studies should focus on postmenopausal women with elevated risk factors. This abstract was presented at the American Physiology Summit 2025 and is only available in HTML format. There is no downloadable file or PDF version. The Physiology editorial board was not involved in the peer review process.