CurraNZ shines in first ever rugby-specific blackcurrant performance study

Supplementation with performance-enhancing CurraNZ has been found to improve speed and agility and rugby players

A study¹ has shown that anthocyanin-rich berry extract supplement can improve performance relating to dynamic speed and agility in Rugby Union players.

New Zealand blackcurrant extract is an ergogenic aid that has been shown to improve aerobic and anaerobic performance by up to 11% in endurance and running-based team sports.

This study shows for the first time how blackcurrant can improve dynamic performance tasks, but not strength or power, in a series of rugby-specific tests. The findings also have implications for other team-based running sports such as football, hockey and basketball.

Thirteen University and Club-level Rugby Union players were assessed following a week’s supplementation of 600mg CurraNZ blackcurrant extract, in a double-blind, placebo-controlled, randomised crossover study design.

The male participants executed a running-based anaerobic sprint test, the Illinois Agility test, seated medicine ball (3kg) throw and hand grip strength task.

Findings showed that blackcurrant:

• Improved average 35m sprint time 1.7%
• 9 out of 13 participants improved their sprint times by an average of 3.3%*
• Improved agility on an average 1.6%
• 9 out 13 participants had improved agility by an average of 3.1%*
• Did not improve handgrip strength or medicine ball throw distance

*Data from personal communication with Professor Willems.

Blackcurrant anthocyanins are linked with vasodilatory, anti-inflammatory and anti-oxidant properties. It seems that they postpone or reduce mechanisms of peripheral fatigue during high-intensity and sprint running, abilities that are important for Rugby Union players.

Mark Willems, Professor of Exercise Physiology at the University of Chichester (pictured, above), who led the study, says: “The data looks meaningful, with a real benefit for improving sprint times and agility in the individuals who responded to New Zealand blackcurrant extract. The study was slightly underpowered but we still saw moderate effect sizes in those who responded to the supplement.” 

This is the first rugby-specific study assessing whether blackcurrant could aid performance involving multiple subsequent performance tasks with limited recovery time.

Professor Willems adds: “It’s a very applied study design - we wanted to simulate the lack of recovery time that is experienced in sports settings where players go from one task to another in a game. 

“These individuals were subjected to a series of tests that would have created fatigue and yet there was still a demonstration of enhanced performance with blackcurrant.”

In repeated sprint tests, a performance improvement above 1.8% is considered a meaningful change.

Professor Willems adds: “This study showed that blackcurrant is also reducing slowing in sprint times. We’ve seen this in earlier projects, so it is nice to see this confirmed again.”

The Illinois Agility test assesses dynamic running performance involving accelerating/stopping and sudden changes in running direction, common in team-based running sports where high-intensity, repeated movements and horizontal change of body position are required. CurraNZ supplementation allowed Rugby Union players to turn in different directions with enhanced speed. 

Professor Willems says: “We’ve never previously undertaken a blackcurrant supplementation performance study that has tested dynamic agility. So, it is very nice to see that there was an effect, particularly when the participants would have been experiencing fatigue after completing the anaerobic sprint test, with only two minutes of recovery in between.” 

CurraNZ has previously been shown to reduce running fatigue by 12% in a single repeated anaerobic test involving academy-level youth footballers², and improved high-intensity, repeated running on average 11%³.

References

1. Effects of anthocyanin-rich New Zealand blackcurrant extract on Rugby Union specific tests, Sports August 2022, 10, 152. Burnett, M Willems https://doi.org/10.3390/sports10100152P.
2. Effect of New Zealand Blackcurrant Extract on Performance during the Running Based Anaerobic Sprint Test in Trained Youth and Recreationally Active Male Football Players. C Godwin, Matthew D. Cook and Mark E. T. Willems. Sports 2017, 5(3), 69; https://doi.org/10.3390/sports5030069
3. Effect of New Zealand blackcurrant extract on performance during the running based anaerobic sprint test in trained youth and recreationally active male football players. Sports 5, 69, 2017. doi:10.3390/sports5030069.