At some point in every HYROX race and every hard workout you hit that wall.
Your breathing turns shallow. Your legs burn. Your brain whispers, “Back off.”
That’s where the race truly starts.
Because from that moment on, it’s not about muscle it’s about mindset.
We call it the SISU mentality.
1. What Is SISU?
SISU is a Finnish word that doesn’t translate perfectly into English but it’s the best description of what separates those who finish strong from those who fade.
It means resilience, grit, determination, and inner strength when the tank is empty.
It’s not motivation. Motivation is what gets you to the start line. SISU is what gets you to the finish.
“When it hurts, that’s when SISU begins.” — Coach Grimmy
2. The Psychology of Pain in Performance
Pain in HYROX isn’t danger it’s data.
It’s your body’s way of saying this is new territory. The mistake most athletes make is trying to fight that feeling instead of working with it.
Here’s what experience teaches:
- Pain is temporary. Pride is permanent.
- When it hurts, your brain exaggerates the story don’t believe it.
- Your limits are usually 40% mental, not physical.
Learning to stay composed inside discomfort is the difference between surviving and performing.
Read “The Science of Mental Toughness” from Wellbeing Magazine
3. Training SISU — It’s a Skill
You don’t develop mental resilience by reading quotes. You develop it by doing hard things on purpose.
At SISU Fitness, we train discomfort safely and systematically.
That might mean:
- Finishing every interval even when the pace drops.
- Holding form under fatigue.
- Running the last kilometre when your legs are gone.
SISU is built rep by rep — just like strength.
4. The Power of Presence
When you’re deep in the pain cave, the key is focus.
Don’t think about the next 100 wall balls — think about the next rep.
Don’t panic about the last 3km — just run the next 200m well.
Break big challenges into small wins.
Every rep completed is proof you’re still in control.
Take on the 100 Wall Ball Rep Test
5. SISU in Life
The SISU mentality doesn’t stay in the gym — it spills into everything.
Work. Family. Health. Business.
Because once you’ve faced the voice that says “stop” and chosen to keep going, everyday problems don’t hit the same.
You’ve already proved you can do hard things — that’s real confidence.
SISU isn’t about perfection. It’s about showing up and staying in the fight, even when it hurts.
“You don’t rise to the occasion. You fall back to your level of training — and your mindset.” — Coach Grimmy
