The greatness of Radiolab knows no limits. Hosts Jad and Robert ask,

How much can you jam into a human brain? How far can you push yourself past feelings of exhaustion?

To answer this they explore….

…the moment the muscle cells in the legs of an ironman competitor give out, the voice in your head telling you for a change, to not to stop, but to keep going, an athlete’s grasp on reality in an insane no-sleep cross country bike race, the Central Governor Circuit in your brain hoarding your body’s secret energy stash, a journey into the infinitely vast minds of the world’s greatest memory champions, and the greatest case of Not Showing Your Work in the math equation having it royally bite you in the ass.

As if I need to say it, a fascinating listen.