Performance-enhancing vegetable

A shot of beetroot juice could be a natural performance enhancer for elite athletes, according to Australian researchers.

A joint study from The University of Western Australia, the Western Australian Institute of Sport and the Australian Institute of Sport has examined the influence nitrate-rich beetroot supplements had on physiological and performance outcomes in elite kayakers.

Six national-level male and five international-level female kayakers took part in a two-part study overseen by scientists including Dr Peter Peeling from UWA’s School of Sport Science, Exercise and Health.

“We looked at the difference that the use of a commercially available 70 mL beetroot shot made to the time-trial performance and paddling economy of the athletes involved,” Dr Peeling said.

“In laboratory-based four-minute ergometer tests, the beetroot supplement had a small effect on the distance covered, but was effective in improving the task economy of the male kayakers. When we used a greater volume of beetroot juice (140 mL) among our female participants during a field-based 500 m kayaking time trial, we found there was a meaningful performance improvement of 1.7%.

“Given that the margin between gold and silver medals in the Men’s K1-1000 m and the Women’s K1-500 m races at the 2012 London Olympic Games was 0.3% and 1.0% respectively, the relatively small performance changes that we recorded are clearly relevant.”

Dr Peeling said the nitrate in beetroot juice has been shown to improve “the efficiency of processes that occur in the mitochondria, which are the cell’s energy factory”.

“This means ATP, the molecule known as a cell’s energy currency, can be spared during muscular activity, resulting in a decreased oxygen cost for a given task.

“If you can find a way of reducing the oxygen cost of a given activity, you might improve the ability to withstand the exercise intensity for a greater period of time, or you find a greater level of output for the original oxygen cost,” he said.

Beetroot juice is known to improve explosive power and activate fast-twitch muscle fibres, although current research has not established why. Dr Peeling said it was becoming increasingly common to see an athlete with red, beetroot-stained lips at an endurance event.

The study was published in the International Journal of Sport Nutrition and Exercise Metabolism.

Caption: UWA Engineering Graduate Reece Baker, who took part in the beetroot trials.