The This Morning star took to the comments section on Rylan's post to compliment him, writing: "Wow," with the flexed bicep emoji.
Rylan's post showed a before and after of his back, following two weeks training with PT and founder of the Six Pack Revolution Scott Harrison. Rylan captioned it: "2 weeks in @iamscottharrison."
He sparked a huge response from his fans as several, much like Ruth, were keen to applaud him.
One wrote: "Good work," while another said: "Looking good Rylan," and a third added: "GO ON!" Others simply left the heart, flame or applaud emoji.
Rylan shared a before and after photo on Instagram
His fitness push coincides with the star making some major decisions following his split from husband Dan Neal, with him now dropping his hyphenated last name from his social media accounts.
Similarly, it seems the star also asked the BBC to remove his married name from the credits of Strictly: It Takes Two, which he hosts alongside Janette Manrara. While the dancer was listed by her full name, Rylan appeared by just his first name.
Rylan and Dan split in the summer
He was also seen without his wedding ring, which he had continued to wear for some time following the split.
Rylan and Dan, a police officer, started dating in 2013. They got engaged the following year during a trip to Paris and were married in November 2015.
Rylan confirmed the end of their marriage in June. He released a statement reading: "Following reports about Dan and I spending time apart, I feel I have to speak out - as the way it is being reported is unfair. I have made a number of mistakes which I deeply regret and have inevitably led to the breakdown of our marriage."
He continued: "I have taken time away from work as I am not in a good place at the moment and am seeking help. I am trying to take each day at a time and would like to thank everyone for their support and for respecting our privacy at this time."
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