A large body of evidence has shown that placebo effects of dietary supplements can improve sport performance. However, very few studies are conducted outside of the laboratory. This is important given that placebo effects may be more likely to be induced during highly controlled, artificial environments in the presence of a researcher. In the past three years, home-based, virtual-reality cycling has increased in popularity, where over 3-million athletes train or compete against athletes worldwide. The aim of this study was to examine placebo effects of an acute dose of beetroot juice during 20-minute cycling virtual reality time-trials. In line with the CONSORT statement, we used a between-participant, randomised balanced placebo design, and recruited 67 trained cyclists who performed 3x20-min cycling time-trials (familiarisation, baseline and experimental) on a virtual-reality software at home. During experimental trials, participants were randomised to one of four groups: 1) told beetroot juice/given beetroot juice, 2) told beetroot juice/given placebo, 3) told placebo/given beetroot juice, and 4) told placebo/given placebo, who received nitrate-rich beetroot juice (containing ~552 mg nitrate) or nitrate-depleted placebo (containing ~0.2 mg nitrate). Compared to baseline, performance during experimental time-trials was not different in any of the groups (effect size range: 0.00 to 0.14). Our results, indicate that placebo effects and beetroot juice do not improve virtual-reality 20-min cycling time-trial performance. These results have important considerations for future research to determine the occurrence of placebo effects and effectiveness of dietary supplements outside of the laboratory.