Outstanding CurraNZ breakthrough reveals never-seen-before effect on oxygen use in muscle tissue

IN recent years, CurraNZ research has put New Zealand blackcurrant extract on the international map as a leading performance-enhancer in cycling and running-based sports.

Now, British scientists have discovered two novel mechanisms that may help explain some of its actions.

A climbing study has revealed that the anthocyanin-rich berry extract can significantly increase the ability of muscle to extract oxygen.

The project, performed on forearm blood flow and muscle oxygenation in climbers, also showed that our berry accelerates muscle recovery.

After 7-days intake of 600mg daily CurraNZ blackcurrant extract, 12 intermediate-ability climbers performed isolated forearm contractions to exhaustion. 

Blood flow and muscle oxygen in the forearm were measured. Findings showed:

• On average, the time to half recovery of muscle oxygenation went from 42 seconds to 26 seconds – indicating muscle tissue reoxygenation rate improved on average 38%
• Tissue saturation index indicated that the muscle extracted 14% more oxygen from the blood
• There was no change to forearm blood flow (brachial artery)

 
Professor Mark Willems of the University of Chichester (left), who is co-author on the study, was very happy to have expert colleagues on board for the climbing study.

The University of Chichester researcher who led the study, Dr Julia Potter, says the findings are exciting.

She says: “Blackcurrant is allowing more oxygen to be removed from the blood’s oxygen transporter, haemoglobin, and deliver it to tissues. Then the muscle is using more of that oxygen during contraction.”

“Previously, we theorised that blackcurrant would dilate the brachial artery and enable greater blood flow to the region, but the changes we observed weren’t due to any change to the brachial artery, but are rather down to oxygen extraction by the tissue.

“It’s a fascinating new finding but it opens up many more questions about how New Zealand blackcurrant extract is doing something ‘more’ to the oxygen cascade.”

Dr Potter says this new insight on blackcurrant’s impact for rapid recovery goes beyond climbing. She says: “This finding has implications for many sports. There’s no limit to it.

“With blackcurrant supporting oxygen availability, you’re going to fatigue less, maintain decision making and it’ll make a difference to sporting outcomes – completely.”

University of Gloucestershire study co-author Dr Simon Fryer, an exercise physiologist and climbing specialist, is a leader in the field of non-invasive assessments of vascular function.

Dr Fryer and his research group previously discovered that delivery and use of oxygen to the forearm muscles is the primary determinant of performance in climbing. The idea that a supplement could aid performance in a sport defined by forearm performance is exciting.

Dr Fryer says: “This manuscript acts as a good starting point for some areas of future research. We can now design studies that assess oxygenation in different settings to see whether it can be used as a performance enhancer.

“I’m not aware of any other supplements that have shown changes at the level of the muscle in rock climbers. As such, it is surprising and interesting for future work.”

Climbing is one of the fastest-growing sports in the UK and will become a new Olympic sport at the Tokyo 2021 Games.

Professional climbing coach Jon Redshaw, one of the instigators behind the introduction of climbing at the Olympics, observes: “The importance of forearm blood flow for climbing performance, training and recovery can’t be stated enough. The research into CurraNZ is exciting and opens up the possibility of new performance gains for climbers. This is a supplement I would recommend to all serious climbers to try.”

New Zealand Blackcurrant Extract Enhances Forearm Muscle Oxygenation During and Following Isolated Exhaustive Forearm Exercise in Intermediate-Level Rock Climbers was published in the International Journal of Sport Nutrition and Exercise Metabolism, https://doi.org/10.1123/ijsnem.2019-0365