PUBLISHED: 19:55 EST, 25 April 2012 | UPDATED: 20:30 EST, 25 April 2012
It seems a most unlikely performance booster but new research suggests beetroot could be the secret to track success at this year’s Olympics.
Scientists have discovered athletes who eat baked beetroot before a race run faster than their rivals.
The purple root vegetable contains high levels of chemicals called nitrates, which have been shown to boost exercise performance.
Researchers at St Louis University in the US recruited 11 fit and healthy men and women and got them to twice run five kilometres on a treadmill.
Before the first run, the volunteers consumed a portion of baked beetroot just over an hour before hitting the treadmill.
Before the second run, they ate an equivalent amount of cranberry relish, chosen because it has a similar calorific content to beetroot but without the same nitrate levels.
The results, published in the Journal of the Academy of Nutrition and Dietetics, showed that after eating the cranberry relish, the runners averaged a speed of 11.9 kilometres per hour, or 7.3mph.
But after scoffing beetroot, their average speed went up to 12.3 kilometres per hour, around 7.6mph.
Researchers said runners appear to be able to maintain their speed for longer if they have eaten the vegetable.
In a report on their findings, they said: ‘During the last 1.1 miles of the run, speed was five per cent faster in the beetroot trial.
‘Consumption of nitrate-rich, whole beetroot improves running performance in healthy adults.’
The findings support earlier research, published in 2009, by British scientists which suggested drinking beetroot juice could have a powerful effect on stamina and endurance, as well as lower blood pressure.
The researchers, from the University of Exeter and the Peninsula Medical School, also in Exter, recruited eight healthy young men to complete a series of cycling tests.
They took them twice – after drinking beetroot juice once a day for six days and after drinking blackcurrant cordial.
When tasked with cycling at an easy pace, the men used less oxygen after drinking beetroot, suggesting their muscles were able to do the same amount of work while spending less energy.
When they were asked to cycle for as long as they could before stopping, the beetroot juice allowed them to pedal an extra minute-and-a-half before running out of energy.
This 16 per cent increase in endurance could mean someone who normally runs out of steam after jogging for an hour would be able to keep going for an extra ten minutes.
It is thought nitrates lead to the blood vessels widening, improving oxygen supply to the muscles.