The former reality star went on to say it's the first time he's "enjoyed training" rather than "focusing on how (he) look(s)".
"Anyway I didn't plan on posting this (hence the lush sticks face mask, which is awesome btw thanks @_samuellevi 😂) But I just thought f**k it, hopefully it kicks someone into gear to take the first step, whatever that may be. You'll feel so much better for it."
Darvid also included a picture from his final year of high school, which is what inspired him to kickstart his fitness journey.
"Oh and the last picture is of me in the last year of school where when I saw that photo I woke up the next day and changed everything, losing 25kg over 6 months 😅," he ended the post.
The candid confession received plenty of praise from his followers, as well as fellow bachie alumni.
"👏👏👏 Awesome work mate," penned the most recent Bachelor Jimmy Nicholson.
Former SAS Australia star and Australian Rules footballer Sabrina Frederick also shared her support, writing: "Yes brother 🙌🏾."
Darvid first hit our screens on Brooke Blurton's season of The Bachelorette, going on to win the season and her heart.
But the relationship was to be short-lived after they announced their split after less than three months together.
At the time of the breakup, Brooke was blindsided when Darvid shared the news publicly on Instagram.
The reality star told NITV that she was left with "no choice" in the break up being made so public, and wished Darvid would have waited to announce it.
"I feel like it was just to humiliate me, have one over me. What else did I have to do? I was silenced, I was defenceless, I just had to cop it," she said.
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