At just 14 years of age, Von Moger began lifting and for years, had little knowledge about steroids.
"I didn't know what they were - I was just going to the gym and it was great," he explains in the video. "I trained naturally for at least 6 years before I even decided to take them.
"I remember training at the gym with my brothers and some other friends. One year, he (Calum's friend) got a lot bigger and stronger, a lot faster and I was like what the hell is going on, how did he do this? And then we learnt he was taking steroids.
"But I refused to take them, I was happy training natural and just seeing what i can do naturally. Also, it was so unavailable for me, where I grew up, where I was living...and it was illegal."
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But after early success competing in bodybuilding, he was encouraged to take steroids if he ever wanted to place well in the open age group.
"It wasn't until I did the ANB - Australian Natural Bodybuilding competition...I won the junior natural Mr Universe and then I was 20, turning 21 and I had a mentor - I had this hype about winning the universe ... and he said 'if you want a place in the top five, you have to take steroids.'"
After seeing what he was up against, he decided to he would take a cycle to prepare for competition. However, Von Moger says it was important to have the guidance of a coach.
And having been through the process, the Aussie has some sage advice for anyone considering using the supplement.
"Wait until five years of solid training before you even decide to take steroids," he advises.
"You want to see what your body, your potential, your genetics, what you can do naturally before you decide to get some extra help - see where your body can take it.
"Don't let anyone make the decision for you. If you decide you want to take, be responsible, know what you're doing and get them from a reliable source."
Watch Calum Von Moger train up the next generation...
Von Moger also encouraged viewers to make sure their motives behind steroid use weren't misguided.
"Have a real reason to take them, don't just take them because you want to grow muscles, or be ripped, or impress a girl or be in the biggest dude in the room or be bigger than you friends.
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"Do it for a competition, do it for a valid reason."
Lastly, the Victorian-born lifter dished the dirt on why people are still trying to hide their steroid use. Von Moger accepts that for many individuals, there are a magnitude of reasons why they try to hide their substance use - whether it be for family reasons or to do with their career. However, he also knows that there are athletes out there who are misleading their fans.
"You can be assured there are certain athletes and fitness people in this industry that say they don't take steroids and say they're natural, but they probably are taking something. You can usually tell how they look - their physique."
"I'm just trying to shed some light - don't let them pour water over your eyes - just because they say something, doesn't necessarily mean it's true. "
