Blackcurrant — a natural, legal performance enhancer?

There are a multitude of options available to rehydrate thirsty athletes, from tap water to expensive brand names that spend millions on endorsements and promotion at major sporting events.

A closer look at the labels of some big-name drinks will reveal that they can be packed with sugar, rather than health-boosting nutrients. But are there options that do more than simply rehydrate?

One fruit that has been popular as a drink ingredient for generations could provide amateur and professional athletes with a safe, scientifically proven and legal boost to their performance, as well as basic rehydration.

The common blackcurrant (Ribes nigrum) has been made into wine, jam and cordials for generations, but more recently the fruit of this woody shrub has been appearing in sports drinks.

However, the use of blackcurrant in sports nutrition is more than just marketing, it has a solid basis in published peer-reviewed science.

Papers published in a range of medical journals have shown that athletes can improve their performance, as well as their overall long-term health, by switching to a blackcurrant sports drink.

 In 2015, a paper that appeared in the International Journal of Sports Nutrition and Exercise Metabolism¹ reported that when cyclists were given 6 g/day of blackcurrant powder for seven days before an endurance test, the production of the metabolic waste lactic acid was reduced by 14% and they had greater strength. Blackcurrant was found to increase the amount of blood that was pumped by each heartbeat and there was less resistance to peripheral circulation.

Another study published in the European Journal of Applied Physiology² looked at the effect of blackcurrant on cyclists. It reported that blackcurrant improved peripheral blood flow by expanding blood vessels so that more blood could flow through with less resistance, and with lower blood pressure. The study also found that blackcurrant increased the ability of the body to burn fat.

Perhaps of most interest to athletes, the study found that the performance of cyclists who consumed blackcurrant improved by 2.4% during a 16.1 km time trial.

A third study published in the International Journal of Sport Nutrition and Exercise Metabolism³ investigated the benefit of blackcurrant consumption by runners. The authors found that runners who consumed blackcurrant performed better in sprints and were able to cover greater distances during set times. Blackcurrant also appeared to help the body get rid of lactic acid faster.

In 2014, the European Journal of Sport Science⁴ published a study that looked at the performance of female runners who had consumed a blackcurrant sports drink. They found that the performance of the runners who consumed blackcurrant improved by 1.9%, on average.

An earlier study, published in 2009 by the American Journal of Physiology⁵, reported that blackcurrant consumption reduced the damage caused by oxygen free radicals, metabolic by-products that are created during exercise.

The antioxidant action of blackcurrant was attributed to the pigments — anthocyanins — that give the black fruit its colour. The authors concluded that blackcurrant would also support an athlete’s immune system.

This body of published science on the benefits of blackcurrant consumption by athletes may encourage sportspeople to drink up. It should be noted, however, that the blackcurrant extracts that are used in sports beverages can vary greatly in the range of compounds retained from the fresh fruit matrix, and thus vary in their nutritional value and potential range of applications.

Fruit processing company Iprona AG uses a membrane ultrafiltration technology to produce a blackcurrant powder that concentrates the original fruit compounds, while also retaining taste and aroma. Iprona suggests that its methods offer the benefits that could be achieved from consuming the fresh fruits. This powder offers applications in sports and nutrition, beyond what can be achieved with powders produced using chemical solvent extraction.

References

1. Willems, ME, Myers, SD, Gault, ML & Cook, MD 2015, Beneficial physiological effects with blackcurrant intake in endurance athletes, International Journal of Sports Nutrition and Exercise Metabolism, vol. 25, no. 4, pp. 367-374. Available from: http://www.ncbi.nlm.nih.gov/pubmed/25811286

2. Cook, MD, Myers, SD, Blacker, SD & Willems, ME 2015, New Zealand blackcurrant extract improves cycling performance and fat oxidation in cyclists, European Journal of Applied Physiology. Available from: http://www.ncbi.nlm.nih.gov/pubmed/26175097

3. Perkins, IC, Vine, SA, Blacker, SD & Willems, ME 2015, New Zealand blackcurrant extract improves high-intensity intermittent running, International Journal of Sport Nutrition and Exercise Metabolism. Available from: http://www.ncbi.nlm.nih.gov/pubmed/25812064#

4. Braakhuis, AJ, Hopkins, WG & Lowe, TE 2014, Effects of dietary antioxidants on training and performance in female runners, European Journal of Sport Science, vol. 14, no. 2, pp. 160-168. Available from: http://www.ncbi.nlm.nih.gov/pubmed/?term=Braakhuis+2014+dietary+antioxidants

5. Lyall, KA, Hurst, SM, Cooney, J, Jensen D, Lo, K, Hurst, RD & Stevenson, LM 2009, Short-term blackcurrant extract consumption modulates exercise-induced oxidative stress and lipopolysaccharide-stimulated inflammatory responses, American Journal of Physiology, vol. 297, no. 1, pp. R70-81. Available from: http://www.ncbi.nlm.nih.gov/pubmed/?term=Hurst+2009+blackcurrant

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