The 30-year-old shared a photo from his gym, writing, "The background is the same the man is not.
"What a journey of self-discipline, sacrifice and adjustment. I have the greatest trainer to thank Brad @bst.fitness."
He continued, "Sure, I went off tracks a few times along the way but he never gave up on me always on my case to push me to be my best!
"If I can do this, believe me hahaha... ANYONE CAN - If you want LIFE to change?? Then you have to apply change to your LIFE."
"Good on you!!! Huge achievement!" one follower wrote.
"Different mind different man," another said.
"Hard work pays off," a third added.
In February, Michael's trainer Brad from BST Fitness shared a post about the MAFS star wanting to make a change, he wrote, "The party is over and the hard work has begun for @mickygoonan. Michael called me because he wants to get fitter, healthier and lose some weight.
"He is a very hard worker and is willing to do what it takes to get the results he wants."
Brad added that Michael had previously lost 10kg with him four years ago in just 10 weeks and "got super fit".
"Over the next 12 weeks, we will be doing a mixture of personals and small group sessions consisting of weights, HIIT, boxing, functional, mobility, core and cross-training. Ensuring he enjoys the training whilst achieving his desired results."
Michael is rumoured to be appearing in the upcoming season of Ex On The Beach with ex-girlfriend KC Osborne.
According to the So Dramatic! podcast, the reality TV stars have been asked to join the series alongside Michael’s MAFS bride Stacey Hampton.
While Michael and KC weren’t paired together on season seven of the Channel Nine show, they dated for five months after filming wrapped.
It’s claimed that the Ex On The Beach producers are hoping for a ‘love triangle’ with the casting of KC, Michael and Stacey.
KC was most recently dating season eight star Jason Engler, before announcing their split earlier this month.
With reporting by Lachlan Guertin.
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