There's an equation every athlete eventually faces: how far can I go? UTMB, Marathon des Sables, sub-10 Ironman, channel swim… Society glorifies the extreme, social media amplifies feats, and the line between pushing limits and recklessness blurs.
In the SAFE PACE episode, Mathieu Blanchard (UTMB podiums, Diagonale des Fous) and Conrad Colman (unassisted Vendée Globe) dialogue on that frontier. What I take from it is more useful than any training plan: the limit isn't physical, it's decisional.
Physiological limit vs acceptable limit
Blanchard puts it beautifully: a trained human body can run 170 km in the mountains. The question is never "am I capable". The question is "at what cost". Immediate cost (injury, hospitalization), medium-term cost (overtraining, immunosuppression), long-term cost (cardiac damage, chronic fatigue).
Colman adds a decisive dimension: the acceptable limit changes with your life. Single at 25, taking 5% mortal risk is a different equation than at 42 with two kids. It's neither better nor worse — it's different. Maturity is knowing it and integrating it.
The 4 warning signs I give my athletes
When ambition becomes risk
- Chronically short sleep (under 6h). The body no longer recovers. Any additional load is net debt.
- HRV in free fall for 3 straight weeks. Autonomic nervous system is dysregulated. You're running on nerves, not on form.
- Loss of morning drive. Motivation is a physiological signal before it's psychological. Its prolonged disappearance is a red light.
- Recurring family or professional conflict around sport. If your circle warns you, listen. Blind spots on your own health are a classic.
The concept of "calculated risk" per Colman
In offshore racing, we accept 0.3% mortal risk per circumnavigation. Not 5%, not 10%. Any risk must be documented, measured, with a withdrawal plan. Otherwise it's not adventure anymore — it's roulette.
— Conrad Colman, SAFE PACE episode
This framework transfers to extreme amateur sport. Before committing to a major objective (first ultra, first Ironman, crossing), ask these three questions:
- What's the abandonment scenario? At what precise point do I stop, no negotiation, no guilt?
- What's my safety net? Who extracts me if I can no longer decide?
- What's my post-race protocol? How do I manage the 7 days after, medically and psychologically?
Ego dressed as passion
Blanchard is lucid: part of the ultra scene confuses passion and escape. Sport over-investment can mask professional, marital or identity avoidance. When extreme effort becomes the only space where you feel alive, it's worth questioning.
What I see in the leaders I coach: the chase for extreme is often correlated with a crisis of meaning at work. The body looks in sport for what the mind no longer finds elsewhere. It's not a judgment — it's a signal to hear.
Pushing the limit — the right way
There's a healthy way to move your limits: progression over 3 to 5 years, not 6 months. That's the trajectory of athletes who last. Blanchard didn't become a UTMB contender in two seasons. Colman didn't finish the Vendée Globe by chance.
In practice, this progression is planned: volume, vertical gain and load/recovery blocks fit together week after week without breaking the body — exactly what I break down in my trail training plan.
Mental preparation is ultra-trail's real playing field — far more than the legs. As a coach, I regularly work through managing limits, fear and risk on extreme formats with my athletes, to give them as many keys to succeed as possible.