He then thanked his personal trainer, Brad, for helping him recover from his partying ways.
'A massive thanks to Brad my trainer for mentoring me through these last eight weeks - you truly reined me in and made me accountable for all my sins,' he wrote.
Before: Michael kept his fitness journey off social media until Wednesday. Pictured here in August 2020 in Brisbane
Michael kept his fitness journey off social media until Wednesday, but he did reveal earlier this month he'd been working out with fellow MAFS groom Seb Guilhaus at the BST Fitness gym in Adelaide.
In a photo uploaded on Instagram, Michael carried a shirtless Seb, 31, in his arms.