Research Latest: CurraNZ 'Supercharges the Fuel Tank' for Muscles

World-first findings reveal how CurraNZ is a powerful catalyst for muscle adaptation and energy metabolism 

A pioneering study (1) has shown that our proprietary blackcurrant extract CurraNZ®, supercharges the “petrol tank”, by increasing the fuel supply in muscles, potentially offering athletes a significant advantage when it matters most.

In practical terms, taking two capsules (600mg) of CurraNZ for just seven days enables muscles to start with significantly greater reserves of glycogen, which is the body’s critical and limiting fuel source during exercise.

The study also found that, alongside boosting starting glycogen levels, CurraNZ promoted fat burning, with users experiencing a 24% increase in fat utilisation compared to placebo.

For any trained athlete, this means starting a session with a far bigger “petrol tank” and significantly boosting performance potential, without any negative side effects. This was borne out in the trial, with CurraNZ boosting athletes’ exercise capacity by 39%.

This new research, utilizing trained male athletes, was published in the European Journal of Applied Physiology. These results are extremely exciting for athletes and highly active populations seeking a genuine performance edge. 

Why muscle glycogen is critical

Muscle glycogen is widely acknowledged as a limiting factor for endurance and high-intensity performance; athletes who store more muscle glycogen have the capacity to go harder for longer - and finish stronger.

Having greater stores of glycogen is like holding an insurance policy for the unknown - ensuring athletes have the extra “fuel in the tank” when it matters most. 

9 out of 10 athletes improved their exercise capacity

There was a trend toward improved performance at the end of endurance exercise, as 9 out of 10 athletes improved their time at the end of the test - meaning athletes not only “go longer” but are more likely to have that crucial finishing kick at the end of a race.

Dr. Sam Shepherd, the study’s lead author (right), explains: “These results show that CurraNZ offers a science-backed advantage to enhance fuelling, by boosting the body’s ability to refill muscle energy stores, recover more quickly and burn more fat during training.

“The performance measure wasn’t the main aim of the study - and it wasn’t powered sufficiently to truly test this - but the data is interesting and shows that 9 out of 10 people had better performance with CurraNZ.

"The performance test itself mimicked a 3-4 minute effort at the end of endurance exercise, for example, trying to break away from a group over the final 1-2 km of a bike race or triathlon.”

As a co-nutrient for carbohydrate re-feeding after hard efforts, CurraNZ can support athletes to recover their glycogen stores more quickly.

'CurraNZ offers a practical advantage for athletes to recover energy stores'

Dr Shepherd says: “Anecdotally, it seems many athletes struggle to meet the recommendations for carbohydrate intake on a day-to-day basis – particularly females and larger men.

“Even professionals get this surprisingly wrong - it’s a common basic error that athletes often do not eat enough carbs to recover sufficiently from their training.”

Dr Shepherd adds, “CurraNZ offers a practical advantage for athletes, to supplement in conjunction with moderate consumption levels of carbohydrate after intense, prolonged or exhaustive exercise bouts, which will lead to faster and higher recovery of muscle glycogen stores.

“There’s a real application for endurance athletes and high-intensity performance, particularly for people who train twice a day or do multi-day races, where there’s short recovery periods between sessions.”

Study provides mechanistic insight for performance and recovery

This latest study is also the first mechanistic analysis showing exactly how CurraNZ works on optimising muscle machinery, deepening and explaining the findings of 34 earlier clinical trials and case studies demonstrating the supplement’s performance, recovery and metabolic effects. Those studies covered a range of individuals, from less fit people to elites, and consistently demonstrated CurraNZ’s powerful fat burning, exercise performance and muscle recovery properties.

A Powerful Co-Nutrient for Fuelling:

Bigger “Fuel Tank”: Seven days’ use measurably increases muscle glycogen and starting energy reserves, with athletes demonstrating a 39% increase in exercise capacity, deserving of follow-up studies.

Faster Recovery: Glycogen restoration after hard sessions is accelerated, reducing recovery time between intense workouts.

Greater Fat Burning: Enhanced fat breakdown during endurance activity supports metabolic health and weight goals for everyone - from recreational athletes to pros – and demonstrated in previous studies.

Stronger Race Finish: A trend for improved sprint ability post-endurance exercise highlights real-world competition advantage.

Trusted Track Record: Prior studies confirm benefits not only in the highly trained, but also less fit individuals seeking improved fat metabolism.

Unique Quality and Science – The Enzans® Factor

The health and sports benefits of CurraNZ® are characterized by Enzans®, key identifiers of the high-potency New Zealand blackcurrant bioactives that deliver the unique, proven, broad-spectrum properties of the supplement.

Only the CurraNZ® Enzans® have been proven in an international program of peer-reviewed health and sports research, making our proprietary formulation the most researched and trusted blackcurrant extract supplement in the world.

With adulterated blackcurrant products on the rise and many claiming false equivalence with CurraNZ, consumers must look for the CurraNZ® and Enzans® trademarks to ensure they are choosing the authentic, science-backed supplements.

Awarded the Nutra Ingredients Asia Sports Nutrition Product of the Year Award in September, no other polyphenol matches our specific, proprietary extract’s unique versatility as a natural metabolic enhancer, nor the repeatability of these results across so many different groups.

Reference

1. New Zealand blackcurrant extract augments muscle glycogen storage at rest and enhances intramuscular triglyceride degradation during prolonged exercise, European Journal of Applied Physiology, October, 2025

About CurraNZ

CurraNZ® is a ten-time award-winning, naturally sourced sports and health superfood supplement made from specific varieties of New Zealand blackcurrants.

Each 300mg capsule delivers 105mg of Enzans™, a proprietary, standardised dose of the bioactive anthocyanins and polyphenols dietetically captured in CurraNZ.

Over 60 CurraNZ-specific published clinical studies have demonstrated the product’s spectrum of fast-acting fitness benefits, including improved running performance of up to 11%, three-times faster muscle recovery and +45% enhanced blood flow during exercise.