Athletes and active adults are leaning more towards nutrient dense foods to improve athletic performance. Diets rich in vegetables like beets are shown to have a significant impact on body functions during exercise. In fact, beetroot juice has become one of the most popular ergogenic supplements for athletes. What makes the beet such an athletic nutritional powerhouse?
Beets and Athletic Performance
The beetroot (beta vulgaris) is enjoyed as a food source, is used medicinally, and continues to grow in popularity as an ergogenic supplement.
Although there are several varieties of the heart-shaped vegetable, the most common among health-conscious people is the red beetroot.
Beets are a rich source of potent antioxidants and also high in nitrate levels. Studies indicate vegetables high in nitrate promote improved health and athletic performance. Nitrate is a chemical naturally occurring in certain foods and is converted into nitric oxide when consumed.
Drinking beet juice raises nitric oxide levels in our body. Research shows nitric oxide can increase blood flow, improve lung function, and strengthen muscle contraction. This combination has stimulated athletes to supplement with beet juice for improved cardiorespiratory endurance and performance.
The importance of cardiorespiratory fitness for athletes and active adults is essential. This component of physical fitness refers to the ability of the circulatory and respiratory systems to supply oxygen to working muscles during prolonged exercise.
Nitric oxide (NO) works by stimulating body functions affecting oxygen utilization. It opens up our blood vessels (vasodilation) increasing blood flow and feeding more oxygen to working muscles.
Nitric oxide also functions as a signaling molecule communicating with our cells and body tissues. This communication ensures more blood flow to the muscle and adequate oxygen intake inside the muscle.
It appears beets have provided a competitive edge for athletes and can improve performance by almost 16 percent according to preliminary research.
Beet juice studies have been conducted on athletes in a variety of sports including running, swimming, cycling and power walking. The common goal of all research was to examine the beneficial effects of beetroot juice on athletic performance.
A study was published on beetroot juice supplementation and aerobic response in fourteen male swimmers. The participants were master athletes aged in their mid to late thirties and in excellent health. Controlled swim tests were conducted with and without beetroot juice supplementation. The athletes were evaluated throughout the swim test for maximum volume of oxygen (VO₂) and aerobic energy cost.
The swimmers significantly increased their anaerobic threshold after beet juice supplementation compared to testing without. This means increased oxygen capacity allowed them to swim longer before reaching exercise failure after drinking beet juice. The athletes were also shown to have a decreased aerobic energy cost supplementing with beet juice. A lowered energy cost enabled the swimmers to sustain an increased exercise time.
The results indicate beetroot juice supplementation may enhance the athletic performance of master trained swimmers.
Other Research Findings
A systematic review was conducted on several articles studying the effects of beetroot juice and improved cardiorespiratory endurance in athletes. More than twenty articles were selected to be studied. The focus of the review was to determine the effects of beetroot juice alone and in combination with other supplementation on cardiorespiratory endurance in athletes.
The articles covered a wide spectrum of sports and included both male and female athletes. Among the athletes indicated were kayakers, triathletes, cyclists, swimmers, runners and healthy active adults. The following results from these studies and have been summarized below:
- Beetroot juice supplementation appears to enhance aerobic performance in both trained male and female athletes. The volume of oxygen utilized at varying intensities was greatly improved after beet juice consumption.
- Kayakers supplementing with beet juice before competition showed improved oxygen capacity compared to a placebo group.
- Trained swimmers exhibited greater exercise capacity and improved endurance after beet juice consumption.
- Competitive cyclists who supplemented with beetroot juice improved their performance by 0.8 percent in a 50-mile test. Significant improvements were observed during the last 10 miles. Both oxygen efficiency and time to exhaustion were greatly improved after beet juice consumption.
- All athletes were able to maintain exercise intensities from 60 to 80 percent significantly longer during exercise with beet juice supplementation.
- Trained runners ran 5 percent faster in the later part of a 5000-meter race supplementing with beetroot juice 90 minutes prior to their event.
- Athletes seem to benefit most from beet juice supplementation 150 minutes prior to their events.
- Research suggests supplementing with beetroot juice at least six days prior to intense exercise or athletic events for best ergogenic benefits.
- Active healthy adults supplementing with beet juice for 15 days showed an increase in power and oxygen during sustained exercise.
- Beetroot juice supplementation is shown to promote mitochondrial biogenesis. Exercise causes cellular stress and mitochondrial biogenesis is a process where our body increases energy in our cells.
- It is suggested beetroot juice supplementation may improve muscle contraction functions.
- Beet juice is indicated to improve cardiorespiratory fitness in athletes performing in higher altitudes. Best results were reported when beet juice was supplemented at least six days prior to their events.
- The timing of beetroot supplementation appears to be a factor for best athletic performance results. Consuming beet juice at least 150 minutes prior to intense exercise is recommended.
- Caffeine appears to interact with beetroot juice and mask the ergogenic benefit.
- Peak nitric oxide (NO) blood concentration occurs within 2 to 3 hours after beetroot juice consumption. Optimal ergogenic effects have been observed after 150 minutes of consuming beet juice.
- Oral antiseptic rinses can lessen the effect of nitrate levels in beet juice and are not recommended.
- Most research was conducting using a 500ml beetroot supplement dose for best ergogenic results. This is approximately 2 cups of juice or 384 grams.
- The most common side effect reported was beeturia (red urine) and red stools.
Other Health Benefits
Consuming beets or beet juice may boost our athletic performance but is also a popular superfood for overall health improvement. Consuming beetroot juice has shown to help with the following:
According to chronic studies on hypertension, beetroot juice is high in nitrate. When we eat beets or drink beet juice, nitrate is converted into nitric oxide. Nitric oxide is a vasodilator and functions by relaxing and dilating our blood vessels for increased blood flow. This directly affects the pressure within our blood vessels. Research indicates a significant decrease in blood pressure three hours after drinking 500ml of beetroot juice. These findings suggest dietary nitrate found in beets as a natural low-cost way to treat hypertension and reduce the risk of cardiovascular disease.
Beets contain powerful antioxidants or phytonutrients that may help reduce the risk of cancer. It appears red beetroot extract has similar cancer-fighting compounds as some anti-cancer prescription drugs. Betanin, which is a food dye extracted from beets is shown to be biologically active. Research has discovered betanin helps reduce the size of breast and prostate cancer cells. These findings have stimulated further examination to confirm the chemopreventative potential of beetroot extract.
Beets are a rich source of antioxidants that help cleanse the body of toxins. They contain betaine and pectin essential to cleansing the liver so toxins are not reabsorbed by the body. Drinking the beet juice instead of cooking raw beets is said to better preserve betaine levels. Higher betaine levels stimulate the liver to get rid of toxins. Decreasing the toxin levels in our body helps reduce inflammation, promotes healing, and is shown to reduce the risk of chronic illness and disease.
Beets and beet juice are a rich source of betalains. Betalains are phytonutrients shown to help reduce inflammation in the body. They function by lessening the activity of certain enzymes that can trigger inflammation. Studies show decreased inflammation from beetroot juice can help reduce our risk of heart disease and Type-2 diabetes.
Foods High in Nitrate
Beets are an amazing source of concentrated nitrate and other nutrients shown to improve our health and fitness. According to research, approximately 80 percent of dietary nitrates come from vegetables like beetroot. According to the American Journal of Clinical Nutrition, the following chart will be helpful in selecting vegetables according to their level of nitrate:
|Nitrate content (mg/100g fresh weight)||Vegetable Varieties|
|Very low, <20||Artichoke, asparagus, broad bean, eggplant, garlic, onion, green bean, mushroom, pea, pepper, potato, summer squash, sweet potato, tomato, watermelon|
|Low, 20 to <50||Broccoli, carrot, cauliflower, cucumber, pumpkin, chicory|
|Middle, 50 to <100||Cabbage, dill, turnip, savoy cabbage|
|High, 100 to <250||Celeriac, Chinese cabbage, endive, fennel, kohlrabi, leek, parsley|
|Very high, >250||Celery, cress, chervil, lettuce, red beetroot, spinach, rocket (rucola)|
The nitrate found in beets and other foods can be metabolized into nitric oxide (NO) shown to enhance athletic performance and improve cardiovascular health. The strength of the evidence indicates nitrate-rich plant foods and especially beets to provide significant health benefits. Beets can be consumed by cooking the vegetable, drinking the juice or even through a dehydrated powdered supplement. Enjoying a glass of beetroot juice before your next workout may just provide the boost you need.
Jonvik KL et al., Habitual Dietary Nitrate Intake in Highly Trained Athletes, International Journal of Sports Nutrition and Exercise Metabolism, 2016.
Lee J. Wylie et al., Beetroot juice and exercise: pharmacodynamic and dose-response relationships, Journal of Applied Physiology, 2013.
Marco Pinna et al., Effect of Beetroot Juice Supplementation on Aerobic Response during Swimming, Nutrients, 2014.
Raúl Domínguez et al., Effects of Beetroot Juice Supplementation on Cardiorespiratory Endurance in Athletes. A Systematic Review, Nutrients, 2017.