Sarah is among a host of celebrities - including former TOWIE star Lucy Mecklenburgh - preparing to show off their gymnastic skills in the BBC One series.
Despite the blood, sweat and tears, Sarah actually looked in good spirits today (10 July) as she straddled a beam in the gym.
Wearing all-black and with her hair tied back off her face, the singer smiled at the camera as she took some time out from training.
The picture has since been shared on the official BBC One Twitter page, after the team visited Sarah and former Steps star Ian 'H' Watkins, who is also taking part.
The caption read: "We visited #Tumble stars @SarahNHarding and @Ianhwatkins to find out how tough their training regime is..."
H also posed for a picture - and we couldn't help but chuckle when we saw it! In the snap, the pop star is doing the box splits while holding a sign that reads: "In the middle of a pain reaction!"
The picture caption also said: "'It is the hardest thing I've ever done. I wish I'd learnt how to do a somersault in Tragedy.' - @Ianhwatkins."
The BBC has not yet revealed when the show will kick off but we hope it's soon. We can't wait!
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