I’m writing this from the middle of a bit of an American tour. We started in San Francisco, we’re heading into Yosemite and the Sequoia National Forest, and we’ll finish up in Monterey.

On Monday I decided to run 7 miles out to the Golden Gate Bridge. I really enjoyed it. There’s something about seeing a landmark like that in all its glory, not through a car window or from a viewing platform, but by running right up to it under your own steam. And somewhere in those miles it got me thinking.

Because I’m fit enough to do these things, I’ve seen some amazing things. I’ve run in -19 through forests in Canada. I’ve run up mountains and through deserts. I’ve run along the canals of Venice. I’ve seen wildlife and sights that most people never get to see. None of that happened because I’m special. It happened because my body was able to take me there.

That’s what this whole project is about. A capable body.

It was never about the six pack

When most people think about fitness, they think about one of two things. Big events, or looking a certain way. Marathons and medals, or six packs and bulging muscles. And look, there’s nothing wrong with either. I do both. I run the events, and I care about how I look like anyone does. Muscles are great, as long as they actually work for you.

But neither of those sit at the top of my list.

The day we landed in San Francisco, my son was shattered. He’s nearly six now, he weighs over 20kg, and he’s too old for a pram. The jet lag had completely floored him. So I carried him on my shoulders for a couple of hours.

That’s it. That’s the reason I train. That’s the reason I write these blogs.

It’s underestimated and it’s under talked about. Being strong enough and fit enough to just live your life fully, to say yes to the run to the bridge, to carry your kid when he can’t walk another step, to climb, explore, play and keep up.

Train to be able to move. To run, to jump, to climb. To move at 40 like you did at 20, and to move at 60 like you did at 30.

Use it, or your body decides you don’t need it

Ageing doesn’t have to mean losing capacity or capability. Yes, our bodies start to slow down. But that just makes it even more important to train them, not less.

They say that after 30 we start losing muscle, gradually, decade by decade. Do you know how you slow that down? You tell your body it still needs that muscle. You train it, you use it, you load it, you ask things of it.

Your body is incredibly efficient. Muscle is expensive to keep, so when it stops being asked to do anything, it starts letting it go. As we age that natural pull gets stronger, and if we’re also moving less, the body takes the hint. There’s more to it than that of course, hormones, recovery, joints, all of it plays a part. But in essence it shows exactly why training matters more as we get older, not less. You train to stay fit, to stay able, to stay capable.

You don’t have to slow right down. That’s a myth.

So much of it is in our heads

Yes, there are physiological changes as we age. I’m not pretending otherwise. But they’re part of the story, not the full story.

A lot of the problems we blame on age actually come from something else. We move less. We do less. We stop running for the bus, stop getting down on the floor, stop lifting anything heavier than the shopping. And bit by bit, we tell our bodies they don’t need to be capable anymore. So they listen.

Forget withering. Forget “getting old” as something that just happens to you. A lot of it is a decision we make without realising we’re making it.

I said it in my first blog and I’ll say it again here. I can’t tell you training will add more years to your life. But I can say for certain it will add more life to your years.

At 41 I can keep up with guys half my age in most things. Not because I’m great, or gifted, or particularly talented. It’s because I didn’t give up. Because I kept training in a way that keeps me able to move.

Don’t let the old man in

Clint Eastwood famously said it. Don’t let the old man in. He’s 96 now. At 91 he was still starring in and directing his own films, and he kept directing well into his nineties. An age most people never see, let alone spend on a film set.

That’s the secret. It’s not a supplement or a hack or a perfect programme. It’s refusing to let the old man (or woman) move in and take over just because the number on your birthday cake has gone up.

Why I actually do this

I didn’t start this project because I’ve got loads of spare time. Far from it. And I didn’t start it for any kind of fame or notoriety, I couldn’t care less about that. If I did, I’d share these blogs far more than I do and I’d post a lot more on socials.

I started it because everywhere I look, I see people around my age giving up. Slowing down before they need to. Deciding that this is just what happens now. And honestly, it breaks my heart.

It doesn’t need to be that way.

We can stay capable well into our later years. We can run, jump, crawl, lift weights, do pull ups, play, and keep up with our kids, and one day our grandkids. But it doesn’t happen by accident. We have to plan for it, train for it, and make it a priority.

So that’s my ask. Whatever age you are right now, start telling your body it still needs to be capable. Go for the run. Get down on the floor. Hang from the bar. Carry the kid.

Don’t let the old man in.