In the last several years, there’s been much interest in the performance-enhancing roles of beetroot supplementation. Beetroot products come in a few varieties, but whether they’re in their natural juice form or a powdered extract, the mechanism is the same: Beetroot is a naturally concentrated source of dietary nitrate and, through a few simple biochemical steps, it becomes nitric oxide.
Past studies show that beetroot supplements acting as a precursor to NO production promote increased blood flow to working muscles during aerobic-type exercise. Other studies show that beetroot extract taken before endurance-style training enhances muscle contractile efficiency, allowing you to push more weight with less energy cost.
Up to recently, however, there have been few studies investigating the benefits of beetroot supplementation on intermittent, high-intensity exercise. Fortunately, a recent systematic review, published in the Journal of the International Society of Sports Nutrition, did just that.
After screening 738 research studies on beetroot juice, the authors found nine studies that met their eligibility criteria (human subjects, direct effects of beetroot determined, high-intensity intermittent exercise). After a comprehensive analysis of these studies, the researchers made the following conclusions:
- Supplementation with beetroot juice reduces muscular fatigue experienced during high-intensity exercise.
- Beetroot juice can help recover phosphocreatine reserves between sets (during resistance training and/or sprint intervals), thus providing more high-energy phosphate for ATP (energy) production.
- Beetroot juice decreases buildup of metabolites such as ADP and inorganic phosphate, which are known to contribute to muscular fatigue.
- Beetroot juice improves calcium release and re-uptake at the sarcoplasmic reticulum, resulting in improved muscle contraction efficiency and power output.
The take-home of these findings? Beetroot is the real deal for those who train hard in the gym.
ACTION POINT: Effective doses of beetroot juice can be attained by drinking one to two glasses (250 milliliters) of natural beetroot juice per day. Beetroot powders and extracts are commonly found in preworkout formulations. That said, if the amount of nitrate is not listed on the Supplement Facts label, take as directed because potency can vary among products. Remember that nitrate levels can build up over time, so even increasing your daily nitrate intake modestly can result in increases in nitrate levels after several days to weeks.