"The background is the same the man is not. What a journey of self discipline, sacrifice and adjustment," he captioned the post.
Michael credited his personal trainer for helping him get into shape.
"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!"
Michael's trainer said the reality star was disciplined and worked hard to achieve his amazing results.
"We’re all so proud of our gym community in Bowden which you play a big part. It has been a tough positive journey," the trainer wrote.
Michael admitted he wanted to make changes in his lifestyle and diet so he could feel confident enough not to wear a rash shirt to the beach.
Michael has been training up to four hours a day ahead of his return to reality television on the upcoming season of Ex On The Beach.
"Michael is in the best shape he's been in his whole life. They've got big plans for him to go in there and flirt up a storm. He is planning to go wild," the friend told Daily Mail.
The company director's ex-girlfriend KC Osborne, who appeared on MAFS season seven with Michael, is also set to star on the reality dating show.
"KC is supposed to fly out to Colombia next month to start filming, and she was told she needed to make it clear she was single," a source said.
Earlier this month, KC confirmed that she and season eight groom Jason Engler had broken up after a brief romance.
"We just don't align with each other and that's that. I'm good. I'm happy," she revealed.