Behind The Research, part 3: 'The evidence for recovery is mounting with blackcurrants'

In part 3 of our ‘Behind The Research’ series, we look at a key pilot study on blackcurrant extract that started to challenge conventional wisdom regarding the use of antioxidants for muscle recovery.

The study

Consumption of anthocyanin-rich extract made from New Zealand Blackcurrants prior to exercise may assist recovery from oxidative stress and maintains circulating neutrophil function: A Pilot Study, (Published in Frontiers in Nutrition, 2019 doi: 10.3389/fnut.2019.00073)

What was study about?

To assess the potential role of New Zealand blackcurrant antioxidants for promoting recovery, immunity and adaptations to exercise. The project assessed several dosing levels and timing of intake.

The dose:

150mg (1/2 capsule), 300mg (1 capsule) and 600mg (2 capsules) of CurraNZ, based on a person weighing 65kg.

Why was this meaningful?

Whether you’re a recreational exerciser or an athlete, there’s a fine line between achieving the maximum health benefits of exercise and suffering the negative effects of oxidative stress, which are harmful substances that are generated by intense training.

Antioxidants help your body cope with the stress of exercise by either directly fighting off these harmful substances or by preventing them from causing damage.

Unfortunately, studies have shown that Vitamin C and E antioxidants impair adaptive benefits from exercise, by blocking oxidative stress, making them a questionable strategy in high doses for muscle recovery.

This study delved into important early-stage questions about blackcurrant's efficacy for recovery and dosing - and whether our berry antioxidants acted in a different manner to its Vitamin counterparts.

What we found:

• One dose of 300mg and 600mg extract taken an hour before exercise had a positive effect on recovery
• Improved first line defences against infections
• Blackcurrant's antioxidant mechanisms behaved differently to Vitamins C and E, by increasing the body's natural defensive pathways and not directly neutralising oxidative stress

What the scientists said about the findings-

“The growing body of research suggests that consumption of New Zealand blackcurrants may have real benefits for those living an active lifestyle,” said Dr Roger Hurst, Biomedical Scientist who led study at Plant & Food Research in New Zealand.

"The benefits are unlikely to be attributable to the antioxidant properties of the extract and due to the blackcurrant extract activating adaptive defensive pathways in cells and tissues. 

"We found that consumption of blackcurrant extract one hour prior to exercise preserved circulating neutrophil function.

“We know functional foods can deliver specific health benefits.

"This is a significant finding that could benefit active people wanting to maintain performance and avoid decreased immune function that can accompany training. 

“Blackcurrant is speeding recovery, upregulating recovery processes and managing the antioxidant defence pathways to stress. It doesn’t suppress but is highly complementary in the exercise recovery process.

“The evidence is now mounting that New Zealand blackcurrants could help people have a more active lifestyle”.

What have we discovered since then?

• Polyphenols act differently to Vitamin C and E antioxidants.
• Antioxidants can be divided into two groups with different modes of action: RONS-sequestrants (like Vitamins C and E that grab onto reactive oxygen and nitrogen species (RONS) to prevent them from causing damage) and Nrf-2 activators (such as blackcurrant polyphenols), which instead donate hydrogen atoms to fight off reactive oxygen species (ROS).
• Blackcurrant’s polyphenols are ‘Nrf-2 activators’ - they regulate antioxidant defences, inflammation, cell function and muscle physiology. These contribute to improved exercise performance, better recovery and overall health benefits associated with physical activity.
• Blackcurrant supports recovery and is complementary for building fitness and amplifying the benefits of exercise.

In case you missed it:

Part 1 - Researchers find CurraNZ effect on blood flow during exercise

Part 2 - CurraNZ shines in muscle recovery study