Blackcurrants, glycogen & going further: new podcast episode

Blackcurrants are having a real “where have you been all my life?” moment - and this new episode of The Physiology of Endurance Running shows why.

Why this episode matters

In “Blackcurrants, the unknown super-supplement?,” exercise physiologist and marathoner Dan Nash talks to Dr Sam Shepherd (left) about a discovery that is changing how athletes think about fuelling: New Zealand blackcurrant extract (CurraNZ) can increase how much glycogen your muscles store before exercise, while helping you burn more fat once you get going.

In simple terms, it gives you a bigger “fuel tank” of carbohydrate on the start line and teaches your body to lean more on fat during long efforts – a double win for anyone racing from 5 km up to ultra distance.

What they unpack together

Across the episode, Sam explains how his lab showed that just 7 days of CurraNZ (600 mg per day) raised starting muscle glycogen and boosted fat use by around a quarter in trained runners, without changing diet or training.

Dan keeps bringing it back to the real world: what this could mean for those final miles when legs usually feel empty, how it might support back-to-back sessions, and why this is so rare to see in already well-trained athletes.

The bigger CurraNZ story

This episode sits on top of a growing stack of more than 60 papers showing CurraNZ can enhance endurance performance, increase fat oxidation and support repeat-day efforts in real athletes, not just lab novices. For runners who like their supplements to be proven, not hyped, it is a rare chance to hear the lead researcher talk through the data in plain language.

Listen in

If you want to understand how a simple purple berry capsule can help you go further before you “hit the wall,” this conversation is well worth an hour on your next easy run.

🎧 Listen here: Blackcurrants, the unknown super-supplement? – with Dr Sam Shepherd.