The rail operator has launched an online ad by M&C Saatchi that features Dai Greene, the Olympic gold medal hopeful, taking a shortcut across the railway line.
It has been designed to highlight the dangers of trepassing on railway lines.
The ad, called "track tests", features Greene running across the tracks while a train approaches at 80 mph, giving him just 5.5 seconds to cross.
The scenario is repeated another three times, with the addition of more rain and trip hazards.
On Greene's third attempt he does not make it across in time and the voiceover says, "game over".
According to Network Rail, nearly 50 people were killed last year after trespassing across the railway tracks.
In the past 10-years, 88% of people killed while tresspassing were men aged 16-25.
The video has been seeded across various sites, including Facebook and YouTube and will run for four weeks.
Display ads will also run online and on mobile and a Facebook page has launched that acts as the campaign's hub.
M&C Saatchi handled the media.
Dyan Crowther, Network Rail director, operational services, said: "Dai is one of the most fit and agile athletes in the world, someone that we know young men admire, particularly with the 2012 Games so close.
"His message and ours is simple – if he can't survive the shortcut, you won't either."
Network Rail's last safety campaign ran in March last year ran on TV and radio to warn people about the dangers of level crossings.
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