A heart-healthy blackcurrant extract can make 5K runners go ‘impressively’ faster by 38 seconds and offers a cost-effective option versus £200+ performance ‘super shoes’.

The recent study [1] revealed that the berry boosts average 5K running times by a startling 38 seconds.

The berry extract improved performance to the same degree as many months of training – and within two hours of popping the pills.

With six million runners in Britain, the sport is the most popular form of fitness in the UK (Statista), because of its high accessibility, low cost and simplicity.

In recent years, there has been a flight to 5K in Britain, thanks to the hugely popular Parkrun and the NHS-designed-and-recommended fitness program, Couch to 5K. Experts favour the format as a way to promote healthy living through exercise, activity, and socialisation.

Blackcurrants are high in natural antioxidant-rich bioactives called anthocyanins that widen blood vessels [2-4], improve arterial function [5] and boost the blood pressure-lowering effects of exercise in recovery [6]. Blood flow is critical for working muscles and athletic performance.

In this study, the University of Chester tested trained recreational male runners and triathletes after they took three 300mg capsules of CurraNZ® blackcurrant extract—containing 315mg of anthocyanins—two hours before the 5km treadmill test.

In summary, the findings showed:

  • Faster completion times in 88% of respondents
  • Average improvements of 38 seconds, compared to placebo
  • Individual responses up to 5.7%

Dr Samantha Moss, Senior Lecturer in Physiology and Sports Sciences at the University of Chester, who led the CurraNZ study, said, “We were surprised to see the differences in running times between the conditions.

“The novelty is that New Zealand blackcurrant supplement can be used as a performance enhancing aid on an acute basis, which may suit a lot of recreational athletes preparing for a race.

“When added to a nutritious diet, race preparation could be optimised by taking one dose of three capsules of blackcurrant extract, offering athletes a simple approach to achieving meaningful performance improvements to 5km race times.”

Running expert Dr Stefanie Flippin, advisor to CurraNZ, emphasised the significance of these findings for athletes of all levels. “An average improvement of 38 seconds over 5km is enormous,” she remarked. “Faster completion times over shorter distances are harder to achieve and require months – sometimes years – of training. This scale of improvement is impressive.

“What’s great is this supplement is highly nutritious and vastly more affordable than wearing a super shoe, is loaded with other benefits and accessible to the everyday runner.”

Previous studies have shown that a seven-day intake of 1-2 capsules (300 mg-600 mg) of CurraNZ is required to improve cycling and running times. These improvements are linked to changes in cardiovascular and metabolic function. However, the faster running times in this study were achieved without significant changes to carbohydrate oxidation, fat oxidation, heart rate, blood lactate or rating of perceived exertion.

Dr Moss added, “Based on previous studies, we believe these changes might be due to an increase in blood flow, which can enhance lactate clearance. We measured lactate and saw slightly lower values in the blackcurrant condition, but the range of estimates was too big to say this could be one of the mechanisms responsible.

Doing more work to assess the role of blackcurrant extract anthocyanin metabolite profiles might be useful for future work, considering that metabolites in similar compounds have been identified as possible drivers in altering blood flow.”

CurraNZ® is derived from New Zealand blackcurrants, renowned for their exceptionally high levels of anthocyanins and polyphenols. These bioactive compounds, encapsulated in each 300mg capsule, provide a standardised dose of Enzans™, offering athletes a natural edge in their pursuit of excellence. CurraNZ® retails at £23.99 for a pack of 30 capsules.

References:

  • [1] Samantha L. Moss, Edward Brindley, Kevin Enright, Jamie Highton & Richard Bott. The effects of an acute dose of New Zealand blackcurrant extract on 5 km running performance Int J Sport Nutr Exerc Metab 2023 https://doi.org/10.1123/ijsnem.2023-0029
  • [2] Cardiovascular function during supine rest in endurance‑trained males with New Zealand blackcurrant: a dose-response study, Eur J Appl Physiology DOI 10.1007/s00421-016-3512-x
  • [3] Effect of Intake Duration of Anthocyanin-rich New Zealand Blackcurrant Extract on Cardiovascular Responses and Femoral Artery Diameter during Sustained Submaximal Isometric Contraction, Journal of Dietary Supplements, 2021, https://doi.org/10.1080/19390211.2021.1948943
  • [4] New Zealand Blackcurrant Alters Physiological Responses and Femoral Artery Diameter during Sustained Isometric Contraction. June 2017 Nutrients 2017, 9(6), 556; doi:10.3390/nu9060556
  • [5] Effects of blackcurrant extract on arterial functions in older adults: A randomised, double-blind, placebo-controlled crossover trial was published in the journal Clinical and Experimental Hypertension on May 13, 2020. https://doi.org/10.1080/10641963.2020.1764015
  • [6] New Zealand Blackcurrant Increases Post-Exercise Hypotension Following Sustained Moderate Intensity Exercise, International Journal of Sport Nutrition, Y Shan, M Cook, Int J Sport Nutr Exerc Metab. 2023 Jul 6;1-9. doi: 10.1123/ijsnem.2023-0014.