Pinch us: Are we dreaming? Or did One Direction trainer Mark Jarvis actually get Niall Horan, Liam Payne, Calum Hood and Ashton Irwin to all work out together on video? We can't even handle this.

One Direction and 5 Seconds of Summer have been on the road on 1D's Where We Are tour for months. We already freaked when 5SOS sang their appreciation for the guys of One Direction, so you can only imagine our reaction to a video of the bands gettin' their buff on together. Sigh!

In the vid above, Niall, Liam, Calum and Ashton are all working up a sweat by doing jumping jack after jumping jack (or "starjumps," as they are apparently called in England). While jumping jacks aren't as difficult as, say, pumping some iron, they can seriously tire you out -- just ask Ashton.

"When do we stop?" he pants, laughing, towards the end of the video.

If it were up to us, NEVER.

Watch the guys work out together in the video above!

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