Chris Hemsworth Training Hard for 'Men In Black' Spinoff

Chris Hemsworth is getting in even better shape for his new movie and his training session is getting us really pumped to watch him fight off aliens.

The Australian hunk, who's arguably the hottest guy in Hollywood, shared footage of his outdoor sweat session in London for his upcoming film, "Men In Black." Showing off his bulging muscles, Hemsworth is completely shirtless and looks in even better shape than earlier this summer when he was spotted on the beach with Matt Damon.

Jabbing with his sparring partner, the 34-year-old is seen putting all his strength into every blow ... even throwing in a kick at the end that doesn't go as planned.

"Outdoor session in London for MIB!! Cheers to @zocobodypro for posing as an alien and letting me beat up on him," Hemsworth wrote. "Sorry for the boot in the face ?? #MenInBlack."

The actor was first linked to the untitled spinoff in February and fans went nuts when he was spotted on set earlier this month. Details surrounding the film remain somewhat a mystery, one thing's for certain ... while Will Smith and Tommy Lee-Jones are said not to make an appearance, Hemsworth is going to give these aliens a run for their money!