The high volume of tweets sent by fans watching a men's cycling road race at the Olympic Games on the weekend disrupted the electronic updates on racers' times and positions that broadcasters rely on to cover the race in real time, causing some to resort to their own watches to estimate times.
The BBC blamed Saturday's disruption on the Olympic Broadcasting Service, a subsidiary of the International Olympic Committee that provides feeds from Olympic events to broadcasters covering the Games.
But the IOC said spectators using Twitter and other location-based technologies overloaded the network that transmits GPS signals from racers' bicycles to the commentators reporting on the races. The signals from the satellite-based navigation system are transmitted over the same wireless networks used by mobile devices.
Without the GPS signal, BBC commentators were unable to keep viewers informed about the progress of hometown favourite and gold medal hopeful Mark Cavendish in the tense final stages of the race, prompting angry viewers to vent their frustrations on Twitter, likely adding to the congestion at the source of the problem.
One equally frustrated BBC commentator, Chris Boardman, ended up estimating cyclists' times using a watch.
Urgent updates only, IOC urges
The IOC told the Guardian newspaper and other media that fans tweeting or texting from the race and posting updates on Facebook congested GPS and data networks, inhibiting the transmission of real-time race information.
"We don't want to stop people engaging in this by social media, but perhaps they might consider only sending urgent updates," IOC communications director Mark Adams told the Guardian.
At a press conference on Sunday, Adams urged those attending what have been dubbed the first "social media Games" to cut back on the over-sharing.
"Of course, if you want to send something, we are not going to say 'Don't, you can't do it', and we would certainly never prevent people," he said. "It's just — if it's not an urgent, urgent one, please kind of take it easy."
The IOC said the problem was confined to one network and that it was working on spreading the load to other networks to ease congestion.
There were some, including London Mayor Boris Johnson, who warned ahead of the Games that the event would strain the city's mobile and data networks.
Several observers have pointed out in the wake of the weekend disruption that it is the satellite Olympic venues that are especially vulnerable to problems since they did not benefit from the communications upgrades that occurred at the main Olympic Park, which was outfitted with an extensive network of fibre optic cables, cellphone towers and Wi-Fi hotspots.