Like a lot of athletes, I am always on the look out for something to give me an edge. Unfortunately, it is often very difficult to sort out fact from fiction when it comes to fitness aids. However, if something repeatedly survives intense scientific scrutiny, especially double blind, placebo controlled studies, they are likely to be beneficial.
Whatever the truth may be, you can’t go wrong by consuming more beets, although their sugar content is kind of high compared to most other vegetables. The phytochemicals that give it its distinctive dark reddish-purplish color may have some important health benefits, but besides this, beet juice may also give your athletic performance a boost. This boost seems to be due to the nitrates in beets, not the phytochemicals. According to Department of Human Movement Sciences, Maastricht University Medical Centre, Maastricht, The Netherlands:
Six days of dietary nitrate supplementation in the form of beetroot juice (~0.5 L/d) has been reported to reduce pulmonary oxygen uptake (VO₂) during submaximal exercise and increase tolerance of high-intensity work rates, suggesting that nitrate can be a potent ergogenic aid. Limited data are available regarding the effect of nitrate ingestion on athletic performance, and no study has investigated the potential ergogenic effects of a small-volume, concentrated dose of beetroot juice. The authors tested the hypothesis that 6 d of nitrate ingestion would improve time-trial performance in trained cyclists. Using a double-blind, repeated-measures crossover design, 12 male cyclists (31±3 yr, VO2peak=58±2 ml·kg⁻¹·min⁻¹, maximal power [Wmax]=342±10 W) ingested 140 ml/d of concentrated beetroot (~8 mmol/d nitrate) juice (BEET) or a placebo (nitrate-depleted beetroot juice; PLAC) for 6 d, separated by a 14-d washout. After supplementation on Day 6, subjects performed 60 min of submaximal cycling (2×30 min at 45% and 65% Wmax, respectively), followed by a 10-km time trial. Time-trial performance (953±18 vs. 965±18 s, p<.005) and power output (294±12 vs. 288±12 W, p<.05) improved after BEET compared with PLAC supplementation. Submaximal VO₂ was lower after BEET (45% Wmax=1.92±0.06 vs. 2.02±0.09 L/min, 65% Wmax 2.94±0.12 vs. 3.11±0.12 L/min) than with PLAC (main effect, p<.05). Whole-body fuel selection and plasma lactate, glucose, and insulin concentrations did not differ between treatments. Six days of nitrate supplementation reduced VO₂ during submaximal exercise and improved time-trial performance in trained cyclists.
This is neat. So the beet juice improved performance. I think this is due to nitrates being powerful vasodilators(it opens up the blood vessels). I am going to get some beets next time I go shopping.