The Core Mechanism: From Nitrates to Nitric Oxide
The reason behind beets' performance-enhancing abilities is a naturally occurring compound: dietary nitrate. When you ingest nitrates from sources like beetroot, a fascinating and beneficial physiological process begins.
The Nitrate Processing Pathway
- Ingestion: You consume nitrates from beets, often in concentrated forms like juice or shots.
- Oral Conversion: Beneficial bacteria in your mouth break down the dietary nitrates ($NO{3}^{-}$) into nitrites ($NO{2}^{-}$). This is a crucial step, and using antibacterial mouthwash can interfere with this process.
- Systemic Circulation: The nitrites are then absorbed into the bloodstream.
- Nitric Oxide Generation: Under conditions of low oxygen availability, such as during intense exercise, the nitrites are further converted into nitric oxide (NO).
The Physiological Effects of Nitric Oxide
Nitric oxide is a potent vasodilator, meaning it widens blood vessels. This action has several direct benefits for runners and other athletes:
- Enhanced Blood Flow: Wider blood vessels allow more blood to flow to working muscles. This means a more efficient delivery of oxygen, glucose, and other vital nutrients.
- Improved Oxygen Efficiency: Increased nitric oxide enhances mitochondrial efficiency, the powerhouse of your cells responsible for producing energy (ATP). Your muscles require less oxygen to produce the same amount of power, effectively lowering the 'oxygen cost' of exercise.
- Delayed Fatigue: By using oxygen more efficiently, you can sustain a higher intensity of exercise for a longer period before feeling fatigued. This translates to more endurance and faster times, especially in the later stages of a race.
- Better Muscle Contractions: Nitric oxide is also involved in the processes of muscle contraction and relaxation, contributing to overall muscular function during exercise.
Practical Guide for Runners
To leverage the ergogenic effects of beets, timing and dosage are key. Most studies use standardized doses found in concentrated products to ensure consistent results, but whole beets can also be effective.
How to Consume Beets for Performance
- Beetroot Juice: The most common method used in research. Standardized shots are reliable, while fresh juice can vary in nitrate content.
- Beetroot Powder: Can be mixed into smoothies or other drinks, but nitrate levels can be variable depending on the processing method.
- Whole Beets: Eating whole, baked beets is an option. A study showed that 200g of baked beets improved 5k running performance. To maximize nitrate content, it's best to avoid boiling them, as nitrates are water-soluble.
Timing Your Intake for Maximum Benefit
- Acute Dosage: For a one-off performance boost, consume 300–600 mg of dietary nitrates 2–3 hours before your run or race. This allows nitrite levels to peak in the blood.
- Nitrate Loading: For multi-day events or a bigger effect, load your system by consuming nitrates daily for 3–7 days leading up to your race. This ensures consistent, high nitrate levels.
Potential Downsides and Considerations
While generally safe, there are some potential considerations when supplementing with beets:
- Individual Variation: Responses can vary. Elite athletes, whose physiology is already highly optimized, may see smaller marginal gains compared to recreational runners.
- Taste: The earthy flavor of beetroot juice can be off-putting for some. Mixing with other juices or using smaller, concentrated shots can help.
- Side Effects: A harmless side effect known as 'beeturia' can cause pink or red urine and stools. Some may also experience mild digestive discomfort, especially from concentrated products.
- Oral Hygiene: Avoid using antibacterial mouthwash shortly after consuming nitrates, as it can kill the beneficial bacteria needed for the conversion process.
- Medication Interactions: As with any supplement, if you have pre-existing health conditions or take medication, especially for blood pressure, consult a healthcare professional.
Comparison of Beet Forms for Athletes
| Feature | Beetroot Juice | Beetroot Concentrate/Shot | Beetroot Powder | Whole Beets |
|---|---|---|---|---|
| Nitrate Level | Variable, requires large volume (~500ml) | High and standardized (e.g., 400mg in 70ml) | Can be negligible depending on processing | Variable depending on soil and cooking |
| Convenience | Low, requires large volume and refrigeration | High, portable, and quick to consume | High, easy to mix into other foods/drinks | Low, requires cooking and preparation time |
| Digestion | Potential for mild digestive upset from large volume | Higher nitrate load in smaller volume may reduce some issues | Less studied, depends on dosage and formula | High fiber content may affect some individuals |
| Key Benefit | Natural source of dietary nitrates | Consistent, tested, and concentrated nitrate dose | Versatile addition to diet and smoothies | Part of a whole-foods-based nitrate strategy |
| Cost | Varies widely by brand and format | Generally higher cost per serving for guaranteed dose | Varies by brand and quality | Relatively low if purchased fresh |
Conclusion
The compelling reason why beets make you run faster is the conversion of their dietary nitrates into nitric oxide. This natural biological process results in wider blood vessels and improved muscular efficiency, allowing your body to transport and use oxygen more effectively during exercise. For endurance and high-intensity performance, this translates to delayed fatigue and potentially faster times, especially in the final stretches of a race. For athletes seeking a natural and scientifically supported performance edge, incorporating beets or a high-quality beetroot supplement into their nutrition plan, timed correctly, is a valid and beneficial strategy. While not a magic bullet, the documented physiological benefits make beets a worthwhile addition to any serious runner's toolkit.
Visit the US Anti-Doping Agency (USADA) for more information on approved supplements and nutrition.
