Banned running coach Alberto Salazar's links with cycling cheat Lance Armstrong have been revealed

Salazar was so excited about a performance-enhancing supplement he was testing on his runners that he sent an email to Armstrong, asking him to get in touch ASAP.

He was preparing to have the supplement L-carnitine infused into his athletes' systems so it could take effect before the London Olympics.

It was part of a series of doping experiments being bankrolled and supported by Nike.

Some athletes expressed concerns to the US Anti-Doping Agency, sparking a six-year investigation that culminated on Tuesday with a four-year ban.