The father of a 20-year-old “gamer” – who died after playing a marathon session on his Xbox – has launched a campaign to raise awareness about the health risks of playing video games for extended periods of time.

An autopsy revealed that 20-year-old Chris Staniforth from the U.K. was killed by a pulmonary embolism, which is a condition that occurs when one or more arteries in your lungs become blocked.

In most cases this happens when a blood clot travels to your lungs from another part of the body – most commonly the deep veins of your legs. This is called deep vein thrombosis or DVT, according to the Mayo Clinic.

This is a condition that can occur in otherwise healthy people, just like Staniforth.

Risk factors include long periods of bed rest and sitting in a cramped position for an extended period of time. That’s why people are told to get up and walk around and stretch their legs when they’re on long flights.

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Professor Brian Colvin – an expert on blood-related conditions – said it’s "unhealthy" for kids to spend long periods in front of their consoles.

"There's anxiety about obesity and children not doing anything other than looking at computer screens," he told The Sun.

Colvin and other medical experts are now urging kids to take regular breaks when they spend hours in front of their video consoles.

Staniforth’s father, David, is hoping this new campaign to warn parents about the dangers of these marathon video-gaming sessions will sink-in after the death of his son.

"Games are fun, and once you've started playing it's hard to stop,” he told the newspaper. “Kids all over the country are playing these games for long periods — they don't realize it could kill them.”

Staniforth, who had no underlying medical conditions, was complaining of a low heart rate before he collapsed. His father said his son would spent up to 12 hours a day playing his Xbox.

This isn’t the first death related to “gaming.” In 2005, a South Korean died after playing online games for three days without taking a break.

Microsoft – the manufacturer of the Xbox – said it "recommend gamers take breaks to exercise as well as make time for other pursuits."