Initially, you presume this has to be some video trickery, then you see that it's been posted by the official Twitter account of the Australian sevens team.
The video was originally posted to the Instagram account of Ed Jenkins - captain of the Aussie sevens side aiming for Olympic glory later this year.
It features Jenkins showing some immense core and hamstring strength, lowering himself towards the mat, holding momentarily and then bringing himself back up.
Jenkins does have some assistance, as he notes on Instagram. One of his coaches is aiding him by holding down his feet.
No rest for the wicked, back at training working on strength and speed with these Nordics. Thanks @willstuart for the assistance/dead weight.
How about the hamstring strength from #Aussie7s skipper @EdJenkins86!?!
Tag a mate who should try this!https://t.co/lSXvcHgFje
— Aussie 7s (@Aussie7s) March 16, 2016
