A man has sparked backlash on social media after he locked himself in a plane bathroom to “run 5k” during an eight-hour flight.

In a viral Instagram video shared last week, the man, named Dom, set his camera up on the ceiling of the small bathroom before running in tiny circles and repeatedly stepping up onto the closed toilet lid.

The fitness influencer logged his three-mile “run” on the Strava tracking app and shared the data, revealing he had spent a total of two hours and four minutes in the bathroom to cover a total “distance” of 5.27km.

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“Eight-hour flight to Boston, but 5k on your plan (running an Ultra tomorrow),” Dom added in the caption.

Shockingly, it isn’t the first time Dom has pulled the stunt, having shared a similar video in February of him hogging the bathroom for just under an hour during an 11-hour plane journey.

His videos have gone viral, leaving many social media users gobsmacked by his “inconsiderate” behaviour.

“Did you just block the toilet for one hour?” one Instagrammer asked, while another scolded: “You’re the Karen blocking the toilet for one hour to do this!”

“This sort of nonsense shouldn’t be encouraged. Guy could have held up the bathroom for an hour for Instagram clout. What a dork,” fumed a third.

Meanwhile, a flight attendant chimed in to say there’s “no way” staff on the plane would have allowed him to do it.

“I’m crew, and there’s NO WAY I’d let someone be in the lavatory for more than 20 minutes,” they began.

“There’s a reason the lavatory can be opened from the outside. This guy would fly right out, and if he would resist, he’d be treated as a disruptive passenger.”

Another echoed: “Cabin crew are supposed to check the lavatories every 15 minutes, there’s no way they’d let you stay in there for an hour lol.”

A fellow runner even criticised him, saying he would be “so angry” if he were left waiting to use the bathroom for this reason.

“I hope this was while everyone was sleeping, and if so, easier in the aisles,” they commented.

“You’re gonna be the reason when there are no running signs in the toilet,” one more person joked.

Nevertheless, some people were more complimentary about Dom’s videos and praised his dedication to his training plan.

“Peak content, admire this,” one person wrote, while another branded the footage “awesome”.