Power of What We Believe & How to Change It
This is the fourth post in a series about redefining what's possible after 40. Start from the beginning: What If Success and Failure Are the Wrong Metrics Entirely?
We've spent three posts looking at evidence.
The 70-year-olds at Hyrox finishing strong. The 40-something Olympians on podiums. The cultural stories we've absorbed about aging bodies and shrinking possibilities. The moment I laced up my shoes and made it 250 metres before stopping — and called it a starting point rather than a failure.
All of that is true. All of that matters.
But here's the question underneath all of it — the one that has to be answered if anything is actually going to change:
Why is it so hard to believe it's possible for us?
Not for them. For us.
That's the conversation this post is about.
We Each Create Our Reality By What We Agree to Believe
Ray Dodd, master belief coach and author of The Power of Belief, puts it plainly: we each create our reality simply by what we agree to believe. Not by what's objectively true. Not by what the evidence actually shows. But by what we have — consciously or not — agreed is true about ourselves and the world.
That's both a confronting and a liberating idea.
Confronting because it means the ceiling you've been bumping up against isn't necessarily a ceiling at all. It might be a belief you adopted so long ago you can't remember a time without it.
Liberating because beliefs, unlike facts, can be changed.
But first — how did they get there?
How Beliefs Are Built: The Neuroscience
Your brain is a story-making machine. It doesn't experience reality directly — it constructs a version of reality based on patterns it has learned to recognize, and it does this largely to keep you safe and conserve energy.
From the moment you were born, your brain was absorbing information from the world around you — from your caregivers, your culture, your early experiences, your successes and humiliations and everything in between. And every time a pattern repeated, your brain encoded it a little more deeply. Neurons that fire together wire together — this is the basic principle of neuroplasticity, and it applies as much to beliefs as it does to any other learned behaviour.
By the time you were seven or eight years old, the foundational architecture of your belief system was largely in place. Not because someone sat you down and said "here is what you should believe about yourself." But because your developing brain was doing exactly what it was designed to do — finding the patterns, learning the rules, building the map.
The problem is that the map is not the territory.
The beliefs you built as a child — about your body, your capabilities, your worth, what's possible for someone like you — were constructed by a child, with a child's limited perspective, in a specific context that no longer exists. And yet most of us are still navigating our adult lives using that original map.
How Beliefs Sustain Themselves
Here's where it gets interesting — and a little inconvenient.
Once a belief is established, your brain actively works to confirm it. This is called confirmation bias, and it's not a character flaw. It's a feature of how human perception works. Your brain filters incoming information through the lens of what it already believes, noticing evidence that confirms the story and quietly discarding evidence that doesn't.
If you believe you're not athletic, you notice every time movement feels hard and overlook every time it feels good. If you believe it's too late to change, you see the people who didn't make it and not the ones who did. If you believe your body is in decline, you interpret every ache as confirmation rather than information.
The belief feeds the perception. The perception reinforces the belief. The cycle continues — not because it's true, but because the brain is very, very good at finding what it's looking for.
This is also, by the way, why watching those 70-year-olds at Hyrox was such a disruption for me. My brain couldn't file it away as irrelevant. It was too concrete, too undeniable. It created a crack in the story I didn't know I was telling — and through that crack, a different possibility started to breathe.
Mindset: The Bridge Between Belief and Behaviour
Carol Dweck's research on mindset — the distinction between fixed and growth mindsets — is essentially a study in what beliefs do to human behaviour in real time.
A fixed mindset believes that qualities are carved in stone: you're either athletic or you're not, smart or you're not, capable of change or you're not. A growth mindset believes that qualities can be developed — that effort, learning, and experience can genuinely expand what's possible.
What's fascinating is that these aren't personality types. They're beliefs. And they function exactly the way all beliefs function — shaping what you reach for, how you interpret setbacks, what you're willing to try, and how long you persist when things get hard.
The woman with a fixed mindset about her body doesn't lace up her shoes because she already knows how that story ends. The woman with a growth mindset laces up anyway — not because she knows she'll succeed, but because she's genuinely curious about what might be possible.
Mindset is belief in action. Which means changing the mindset starts with examining the belief underneath it.
So How Do We Actually Change What We Believe?
This is the practical question — and it deserves a practical answer.
Dodd's framework, rooted in both Toltec wisdom and everyday psychology, starts with a deceptively simple premise: you cannot change a belief you haven't first made visible. The hidden belief is the powerful one. The one you've never questioned because it doesn't feel like a belief — it feels like the truth.
So the first step is awareness. Not judgment. Not a plan. Just the willingness to hold a belief up to the light and ask: is this actually true, or have I simply agreed to it?
A few ways to start doing this in practice:
Notice the language of limitation. "I could never..." "I'm just not the kind of person who..." "It's too late for me to..." These phrases are belief signatures. When you catch yourself saying or thinking them, get curious. Where did this come from? How old was I when I first agreed to this?
Look for evidence you've been ignoring. If your brain is confirmation-biased toward limitation, you need to actively seek counter-evidence. The 70-year-olds at Hyrox. The 42-year-old making her Olympic debut. The woman in your life who started something new at 55 and never looked back. Not to bypass your experience — but to genuinely widen the frame of what you consider possible.
Act before the belief catches up. This one is counterintuitive but powerful. You don't have to fully believe something is possible before you begin. You just have to act as if it might be — consistently, in small ways — and let the experience start to reshape the belief from the inside out. The 250 metres becomes 500. The 500 becomes a kilometre. The body provides evidence the mind slowly has to reckon with.
Question the source. Many of our most limiting beliefs weren't even formed from our own experiences — they were absorbed from the people around us. A parent's offhand comment. A teacher's assessment. A culture's story about what women's bodies are for and what happens to them after 40. When you find a limiting belief, ask: whose voice is this actually in? Is it even mine?
Be patient with the process. Beliefs that took decades to build don't dissolve in a weekend. Neuroplasticity is real — the brain genuinely can form new patterns at any age — but it requires repetition, consistency, and the willingness to stay with discomfort while the new story is still fragile and the old one is still loud.
What This Series Has Really Been About
We started by questioning whether success and failure were even the right metrics. We looked at what happens when 40-somethings refuse to accept the cultural story about aging. We sat with the honest question of whether our limitations are truth or excuse.
And now we're here — at the root of all of it.
What we believe shapes what we experience. What we experience reinforces what we believe. And the only way out of a loop that's too small for the life you're trying to live is to start questioning the beliefs that are running it.
Not from a place of shame or urgency. From a place of curiosity.
What if that's not actually true?
What if I simply never questioned it?
What if the map I've been using was drawn by a younger version of me who didn't yet know what was possible?
Those are the questions that change things.
Not immediately. Not dramatically. But consistently, quietly, one small act of defiance against the old story at a time.
That's how the becoming happens.
True North Co. exists for women in midlife who are ready to examine the beliefs that have been running the show — and to find out what becomes possible when they do. To Live Life (Mind)Fully.
