Fitspan: The Real Measure of a Life Well-Lived

The Future You Don’t Want

You’re 68 years old, standing at the base of a cobblestone street in Lisbon.
It’s not long—maybe three blocks up—but it’s steep.

Your friends are already halfway to the café with the best view in the city.
You take a step forward. Your knees ache, your back twinges, and your lungs feel like they’re working at max before you’ve even reached the first landing.

You stop. Pretend you “just want to take in the view from here.”
Inside, you feel it—the sting of realizing you can’t.

The Alternative Future

Same age. Same street. Same friends.
This time, you’re laughing as you climb, your legs and lungs strong enough to make the hill feel like a warm-up. You get to the café, take in the view, and toast to the adventures still ahead.

That difference? It’s not luck. It’s not genetics. It’s your fitspan.

Lifespan, Healthspan… and Now, Fitspan

Peter Attia popularized the concept of healthspan—the years you live free from chronic disease and disability.
It’s a brilliant metric because it shifts the conversation from “How long can I live?” to “How long can I live well?”

But there’s a gap.

You can be healthy enough to go to work, cook dinner, and walk around the block…and still not be fit enough to do the things that make you feel most alive.

That’s where fitspan comes in:

Fitspan is the number of years you can still say yes to the adventures that require strength, stamina, and resilience.

It’s your capacity to hike to that alpine lake, bike along the Amalfi Coast, ski powder at 70, or climb the steps to your favorite lookout without gasping for air.

The Fitspan Gap

Here’s the hard truth: most people lose their fitspan years before they lose their healthspan.

You might have no diagnosed illness, but still be sidelined from the activities you love because:

• Your legs can’t handle the climb.

• Your grip can’t hold the paddle.

• Your lungs give out halfway up the hill.

That gap can be decades long.
I’ve seen people “healthy” enough to work but unable to carry their luggage up a flight of stairs by 55.

What Steals Your Fitspan Early

Fitspan doesn’t vanish overnight—it erodes slowly, from the moment you stop training like your future adventures matter.
The biggest thieves:

1. Strength Loss (Sarcopenia) – Muscle mass declines 3–5% per decade after 30 unless you train. This is the single biggest limiter of physical capacity in older age.

2. Cardio Drop-Off – Aerobic capacity can decline 10% per decade after 30. Lose it, and hills feel like mountains.

3. Mobility Restrictions – Stiff hips, tight shoulders, and poor balance don’t just make you move slower—they make some movements impossible.

4. Extra Weight – Even a modest weight gain changes your power-to-weight ratio, making every vertical foot harder.

How to Extend Your Fitspan

The formula is simple, but not easy:

1. Train Specifically for Adventure
   Don’t just “stay active”—train for the real-world demands of hiking, climbing, carrying, cycling, paddling.

2. Lift Heavy, Move Often
   Strength training is non-negotiable. Add frequent low-intensity movement to build your endurance base.

3. Work at Adventure-Level Intensity
   If your trips involve hours of movement, train hours of movement. Short gym sessions alone won’t cut it.

4. Maintain Mobility and Balance
   A body that can’t move freely is a body that says “no” more often than “yes.”

5. Protect Your Power-to-Weight Ratio
   Staying lean is about performance, not vanity. It’s the difference between scaling a trail and dreading it.

Fitspan Is a Choice

You can’t control the day your lifespan ends. You can’t guarantee perfect healthspan, but you can take deliberate action to ensure your fitspan stretches deep into your 60s, 70s, 80s, and maybe even 90s.

Train for the future version of you—the one who wants to keep saying yes to bucket-list adventures, family trips, and spontaneous challenges.

The real tragedy isn’t dying early it’s stopping the adventures while you’re still alive.