A new study has revealed that a chemical present in baked beetroot can help improve an athlete's performance.
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 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.
"During the last 1.1 miles of the run, speed was five per cent faster in the beetroot trial," the Daily Mail quoted the researcher as saying.
"Consumption of nitrate-rich, whole beetroot improves running performance in healthy adults," they said.
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 study has been published in the Journal of the Academy of Nutrition and Dietetics.