Acute Effects of Citrulline Malate Supplementation on Nocturnal Blood Pressure Dipping After Exercise in Hypertensive Patients: A Randomized, Placebo-Controlled Trial.

Background: Citrulline malate (CM), especially when used in conjunction with physical exercise, has demonstrated potential as a non-pharmacological adjunct in the management of hypertension. Nevertheless, its impact on nocturnal blood pressure dipping remains unexplored. Objective: Evaluate the impact of a single dose of CM on nocturnal blood pressure dipping after exercise in hypertensive individuals. Methods: In a double-blind, placebo-controlled, parallel-group clinical trial, twenty hypertensive adults (55 ± 16 years) were randomly assigned to either a CM (6 g) or placebo (6 g of corn starch) group (PLA). Resting blood pressure was measured after a 20-min period of comfortable seating in a calm environment. Both groups underwent 40 min of treadmill running/walking at an intensity of 60–70% of their reserve heart rate, 120 min after ingesting the substances. Ambulatory blood pressure monitoring was employed to measure blood pressure over 24 h. Results: No significant differences in systolic blood pressure values were observed between the CM and PLA groups at rest, during wakefulness, sleep, or over a 24-h period. However, CM exhibited a significant reduction in diastolic blood pressure in several metrics: delta 24 h (-14 mmHg vs −6 mmHg, p = 0.047), delta wakefulness (-12 mmHg vs −4 mmHg, p = 0.024), percent delta 24 h (-16% vs −6%, p = 0.024), and percent delta wakefulness (-14% vs −4%, p = 0.013). No significant differences were found between CM and PLA in terms of systolic and diastolic nocturnal absolute reductions (-13 mmHg vs −12 mmHg, p = 0.808, and −13 mmHg vs −8 mmHg, p = 0.273, respectively) or nocturnal percentage decrease (-9.9% vs −9.4%, p = 0.844, and −15.3% vs −11.7%, p = 0.399, respectively). Conclusions: The study found no significant changes in the post-exercise nocturnal blood pressure dip following a single dose of CM supplementation. However, a notable reduction in diastolic blood pressure was observed during the waking period and over the average 24-h monitoring period. Clinical trial registry number and website: ClinicalTrials.gov platform (NCT03378596). [ABSTRACT FROM AUTHOR]