Bloodflow, fatigue, Rio, performance, blackcurrants

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Curranz blackcurrant extract capsulesWho needs a title when you can just put 5 random words? Well, of course, they’re not really random and those words spring out from the latest research from Prof. Willems @Chichester Uni into blackcurrant supplementation for endurance athletes.

His double-blind, randomized, crossover study, entitled “Blackcurrant Alters Physiological Responses and Femoral Artery Diameter during Sustained Isometric Contraction”, was published in the open-access journal “Nutrients” and can also be found (here).

The study demonstrated that the “Intake of NZBC extract for 7-days altered cardiovascular responses, muscle oxygen saturation, muscle activity and femoral artery diameter during a 120-s 30%iMVC of the quadriceps.”

So essentially we are looking at:

  • More bloodflow means more oxygen giving enhanced performance and reduced fatigue; and
  • More bloodflow can aid recovery by greater nutrient delivery.

curranz Previous research showed similar and other benefits. For example some of the blackcurrant research (as above) shows vasodilatory effects – beet-it shows similar vasodilatory effects but do the two work together? or just do the same thing? I think the jury is out on that question BUT curranz has still been shown to increase fat oxidation as an energy source when exercising – so that is a different and further positive effect.

Let’s finish by saying that members of the GB Olympic team (eg Tom Farrell) use the curranz product.

I don’t get paid for writing any of this by the manufacturers but I do get the odd free sample from time-to-time. And I only get them because I use them because I think they work.

Source: Can also be found (here).

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Would be interesting to see research into whether curranz and beet it do work well together for endurance athletes.


When you say that these supplements may be good for endurance runners, does that also include 5K and up to 10K or are these distances too short for any benefits. I haf tried the beet juice and I see no improvement as far as I can see although there may be. Inquiring minds want to know.

Jacob Riis

Is it ok just to drink black currant “juice” ? I Denmark we call saft or saftevand. I don’t know why there is no word for it in English. Apparently you call it “fruit drink concentrate” You don’t need to spend money on pills but will get a lovely drink …

The Ribena brand is quite popular and this drink has a volume of 30% of concentrated black currant. Would that also work?

It’s hard to believe that only the New Zealand black currants will do the work…