75kg to 100kg — Triathlete to bodybuilder. My Story

No personal trainer, coach, training plan, strict diet, or weight gainers.
Just old-school training and eating.

Ironman Cairns (Left) — Bodybuilder (Right)

It’s taken two years, but the transition feels natural. I didn’t force anything, train like a madman, or try steroids. My biggest growth period has come in the past six months, and I’ll share the key factors at the end.

Here’s my story, split into three parts.

Part One: The Transition Period (Jun 22 — Oct 23)

Starting weight: 75kg
Training: BodyPump & mid-distance cardio
Diet: 50% fewer calories
Injuries: Plenty of them

I had just finished the Ironman Triathlon in Cairns, Australia, completing the course in under 10 hours. According to Google, that’s “exceptional athletic performance” — a time many strive for.

At the start line, I weighed 75kg. After 10 hours of racing in 30°C heat, I likely lost 5–10% of my body weight, mostly water but also muscle breakdown and glycogen depletion. I never weighed myself post-race, but from previous experiences, I know it’s easy to drop 5kg in those conditions. However, for accuracy, I’ll stick with 75kg as my starting weight, since that 5kg was easily…