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    New Zealand blackcurrant extract reduces post-exercise oxidative stress and maintains the body's first line defences

    on April 26, 2021

    New Zealand researchers have found that blackcurrant extract significantly reduces post-exercise oxidative stress markers and maintains the body's first-line defences against infection.

    They also found the resulting attenuation of oxidative stress is unlikely due to blackcurrant's antioxidant properties.

    Published in Frontiers in Nutrition, the study was performed across two trials involving 32 individuals who undertook a 30-minute rowing test at 70%VO2Max.

    Blood was collected during the trial for oxidative, antioxidant, inflammatory and circulating neutrophil status. Bioavailability, timing and dosing were assessed. Participants were administered the berry extract with total anthocyanins doses ranging from 0.8, 1.6 or 3.2mg/kg bodyweight and performed the exercise test an hour later. 

    Results showed:

    • Consumption of blackcurrant extract facilitated recovery from exercise-induced oxidative stress
    • Post-exercise plasma oxidative capacity decreased by 34% (two hours of recovery)
    • Post-exercise protein carbonyls decreased by 32% (two hours of recovery)
    • Timed consumption of the extract offset a decline in neutrophil activity 6 hours post-exercise 
    • Blackcurrant supported an increase in circulating neutrophils during recovery
    • Blackcurrant had no impact on overall plasma antioxidant capacity prior to, or during recovery from, 30 mins rowing

    Circulating neutrophils are the first line of defence against infection and are required for co-ordinating acute inflammatory, tissue repair and appropriate adaptive immune responses. The study found that blackcurrant effectively maintained circulating neutrophils and preserved immune defences.

    Blackcurrant stimulating endogenous antioxidant systems

    The study's observation, that blackcurrant did not alter baseline antioxidant plasma levels, indicates that the berry's effect on exercise-induced oxidative stress is unlikely to be due to the inherent antioxidant properties of the anthocyanin extract.

    Researchers believe that blackcurrant anthocyanins are activating cellular redox-sensitive mechanisms and improving the body's adaptive responses in cells and tissues.

    Nutritional intervention with high-strength antioxidants such as Vitamins C and E have been shown to prevent the adaptive action of ROS/RNS and should be avoided as a post-exercise recovery strategy.

    However, several studies (Myburgh et al 2014, Hurst et al 2012, Trinity et al 2014) on dietary polyphenolics have shown they attentuate exercise-induced oxidative stress independent of their direct antioxidant properties. 

    The researchers concluded that timed consumption of New Zealand blackcurrant anthocyanins can support exercise recovery and maintain natural immune defences, independent of the berry's antioxidant properties.

    Consumption of an 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 Front. Nutr., 29 May 2019 |

    *The 1.6mg/kg and 3.2mg/kg doses in the study are equivalent to the dosing ranges found in one and two capsules of CurraNZ.
    * CurraNZ is a 35% anthocyanin extract made from New Zealand blackcurrants, as used in the study
    *The research supports the functional benefits of CurraNZ, which is backed by a 100% money-back guarantee for muscle recovery