
Journal · Training
The Biggest Mistake
I Made As A
Young Endurance
Athlete.
Why strength training became one of the most important sessions in my week—and why every Col de Sud athlete does it.
If I could go back twenty years and give my younger self one piece of advice, it wouldn't be about running more kilometres, riding harder intervals or buying better equipment.
It would be simple.
Start strength training earlier.
Like many endurance athletes, I grew up believing that lifting weights would make me slower, heavier and more prone to injury. It wasn't just something I assumed—it was something I was told.
For years I stayed away from the gym because I genuinely believed it would compromise my performance.
Looking back now, I realise that was probably the biggest mistake I made in my athletic development.
Strength training has become one of the biggest contributors to my running and cycling—not because it makes me a better lifter, but because it makes me a more resilient athlete.
Strength Isn't About Building Muscle
When people hear strength training, they often picture bodybuilders chasing bigger arms and heavier bench presses.
That's not what we're trying to achieve.
For endurance athletes, strength training is about improving movement quality, producing more force with less effort, maintaining good posture when fatigue sets in and building a body that can handle consistent training week after week.
The goal isn't to become heavier.
The goal is to become stronger where it matters.
Performance Starts Before Race Day
Running and cycling place thousands of repetitive loads through your body.
Strong glutes improve hip stability.
Strong hamstrings protect the knees.
A resilient core helps maintain posture when fatigue creeps in during the final kilometres.
When your body moves efficiently, you waste less energy.
That's free performance.
Not because you've suddenly become fitter overnight, but because you've built a body that can better tolerate training.

Strength Is Also About Longevity
One of the biggest reasons I continue strength training has nothing to do with racing.
Research consistently shows resistance training helps maintain muscle mass, improve bone density and reduce injury risk as we age.
I don't just want to perform well this season.
I want to be running, riding and exploring mountains twenty years from now.
Strength training gives me the best chance of doing exactly that.
Why Every Col de Sud Athlete Strength Trains
Every athlete I coach completes two strength sessions each week.
Sometimes that's in a commercial gym.
Sometimes it's in a garage.
Sometimes it's at home with minimal equipment.
The location doesn't matter.
Consistency does.
I also spend a lot of time reading current research, testing new exercises myself and refining programmes before asking my athletes to do them.
If something improves performance, reduces injury risk or helps athletes enjoy training for longer, it's worth including.

"Train for performance.
Train for longevity."

Final Thoughts
Strength training isn't something you do because you're injured.
It's something you do so you stay healthy enough to keep chasing the adventures that matter.
I wish someone had taught me that twenty years ago.
Now it's one of the first lessons I share with every athlete I coach.
Train for performance.
Train for longevity.
Every athlete has a mountain.
Find your path.
— Phillipe Cossey
Founder · Col de Sud — Ara Maunga

— About the author
Phillipe Cossey
Runner. Cyclist. Triathlete. Founder of Col de Sud.
I believe endurance sport isn't just about racing faster.
It's about becoming stronger through the process.
I've spent years training for endurance events, learning through experience, embracing consistency and discovering that every athlete has their own mountain to climb.
The Col de Sud Journal is where I share those lessons to help others enjoy the journey.
— Your next step
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your mountain?
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