In a recent study done by Jose Manuel Jurado-Castro et al., a beetroot juice supplement was given to a group of physically active women.  The participants were asked to perform a countermovement jump and a back squat at varying intensities and percentages of one-repetition maximum.  For a little background, beetroot juice has been used as supplementation for high-intensity exercise.  The consumption of beetroot juice allows for an increase in blood nitric oxide (NO) concentrations.  The increase of NO concentrations allows for the blood vessels to dilate and for an increase in blood flow, which helps with muscle contractions.  This can help increase muscle contraction speed and force.  In this study done by Manuel Jurado-Castro et al., the supplementation of the beetroot juice 120 minutes prior allowed the female athletes to have an increased countermovement jump, as well as an increase in velocity and power of the back squat. 

Sources:

Domínguez, R., Maté-Muñoz, J.L., Cuenca, E. et al. Effects of beetroot juice supplementation on intermittent high-intensity exercise efforts. J Int Soc Sports Nutr 15, 2 (2018). https://doi.org/10.1186/s12970-017-0204-9

Jurado-Castro JM, Campos-Perez J, Ranchal-Sanchez A, Durán-López N, Domínguez R. Acute Effects of Beetroot Juice Supplements on Lower-Body Strength in Female Athletes: Double-Blind Crossover Randomized Trial. Sports Health. 2022 May 21:19417381221083590. doi: 10.1177/19417381221083590. Epub ahead of print. PMID: 35603411.