The Athlete's Plant-Based Power-Up
For over a decade, elite and amateur athletes alike have been spotted downing shots of deep red beetroot juice before big events. Initially, the buzz was centered almost exclusively on endurance sports like cycling and marathon running. Studies showed
that the naturally occurring compounds in beets could help athletes go farther and longer. The core ingredient of interest is dietary nitrate, which is abundant in beetroot as well as other leafy green vegetables like spinach and arugula. While our bodies can produce their own supply of the molecule that nitrate helps create, research has shown that supplementing with a food-based source like beetroot can significantly boost its availability, offering a natural and legal way to enhance performance.
How a Vegetable Boosts Your Blood Flow
The science behind beetroot's power lies in a simple but elegant biological pathway. When you consume dietary nitrate, bacteria on your tongue convert it into nitrite. This nitrite then circulates in your bloodstream. In areas of the body where oxygen is low, such as in muscles working hard during a sprint, this nitrite is converted into nitric oxide (NO). Nitric oxide is a potent vasodilator, which means it signals the smooth muscles in your blood vessel walls to relax, causing the vessels to widen. This process increases blood flow, allowing more oxygen and nutrients to be delivered to your hardworking muscles precisely when they need it most. The result is improved efficiency; your muscles can produce the same amount of power with less oxygen, delaying fatigue and potentially improving your overall output.
From Marathon Stamina to Sprint Speed
While the benefits for endurance have been well-documented, the scientific focus has recently expanded to include high-intensity, short-duration exercise like sprinting. The results have been nuanced but promising. Some studies show that nitrate supplementation can significantly improve repeated-sprint performance, which is crucial in team sports like football or rugby. Other research highlights its potential to increase peak power output and reduce the time it takes to generate maximum force, giving sprinters a more explosive start. However, the evidence is not universally positive; some studies focusing on single, all-out sprints like the 100-meter dash have found little to no improvement from an acute dose. This suggests the benefits might be more pronounced in scenarios involving repeated bursts of power or in helping athletes maintain force as they begin to fatigue.
The 'Micro-Dosing' Strategy
The term "micro-dosing" in this context doesn't refer to a one-time tiny amount. Instead, it describes a strategy of consistent, smaller daily doses rather than loading up with a single large amount right before a competition. While many studies use an acute protocol—a dose of around 6-8 millimoles (mmol) of nitrate taken two to three hours before exercise—another effective method is a loading phase of three to seven days. This daily supplementation, or 'micro-dosing', aims to keep plasma nitrate levels consistently elevated. The theory is that this approach may not only prepare the body for peak performance on race day but could also enhance the quality of daily training sessions by improving oxygen delivery and muscle efficiency over time. This sustained elevation of nitric oxide could lead to better long-term adaptations in muscle function and power.
Safety and Practical Considerations
For most healthy athletes, beetroot supplementation is considered safe. One common and harmless side effect is beeturia—a temporary pink or red colouration of urine and stools which can be alarming but is not a cause for concern. However, there are more significant factors to consider. Beetroots are high in compounds called oxalates, which can contribute to the formation of kidney stones in susceptible individuals. The most important consideration is beetroot's effect on blood pressure. Because nitric oxide is a vasodilator, it naturally lowers blood pressure. For athletes with low blood pressure (hypotension) or those taking medication for hypertension, adding beetroot nitrate could cause dizziness or fainting. Similarly, it should be avoided by anyone taking other nitrate-based medications for heart conditions or PDE-5 inhibitors.
