Beetroot Juice Enhances Nitrate Metabolism and Endothelial Function but Not Cardiovascular or Strength Performance in Bodybuilders with a History of Anabolic–Androgenic Steroid Abuse: A Crossover Trial

Inorganic nitrate (NO3−) has demonstrated therapeutic efficacy in several populations characterised by cardiovascular risk. However, it is unknown whether increasing nitric oxide (NO) bioavailability affects vascular and cardiovascular responses in men with androgenic–anabolic steroid (AAS) abuse. Objective: To investigate the effects of dietary NO3− on cardiovascular, autonomic, and strength performance in men with AAS abuse. Methods: In this double-blind, randomised, placebo-controlled crossover trial, participants consumed beetroot juice (12.8 mmol 800 mg NO3−) or a placebo (0.3 mmol NO3−). After two hours, assessments included saliva collection, endothelial function, heart rate, and systolic (SBP) and diastolic (DBP) blood pressure at rest, during, and after an isometric handgrip test. Results: Thirteen resistance-trained males mean (standard deviation) age: 31 (9) y; body mass index (BMI): 30 (4) kg/m2; SBP: 132 (3) mmHg; DBP: 70 (2) mmHg completed the protocol. NO3−-rich juice significantly increased salivary NO3− (40.6 μM, p < 0.001) and nitrite (NO2−) (3.1 μM, p = 0.002) versus placebo. Flow-mediated dilation was greater with NO3− both at pre-exercise (2.37%, p = 0.02) and post-exercise (2.57%, p = 0.01). No between-group differences were observed in isometric strength (0.02 kgf, p = 0.99) or systolic/diastolic blood pressure across conditions. Conclusions: Dietary NO3− enhanced salivary NO2− and NO3− concentrations and modestly improved endothelial function but did not reduce the elevated blood pressure or alter cardiac autonomic responses associated with AAS abuse.