The Ascending Influence
There’s a famous engineering story about the Citicorp Centre in New York City. Built in the 1970’s, it was viewed as an architectural marvel, noticeable by its slanted roof and the fact that it stood on four massive stilts. For its time, it looked incredibly futuristic.
(You can find a really good YouTube video about it on the channel Veritasium—Here’s the link).
But around a year after it was built, a student studying the design noticed something odd. The stilts on which the skyscraper stood weren’t at the corners of the building; they were on the middle of each side. He calculated that if a storm were to hit the building at a 45-degree angle, the load from storm-level winds would be too much. The joints would snap, and the entire building itself could potentially collapse.
The issue wasn’t the skyscrapers unusual slanted roof, its expensive windows, or the people working on the 50th floor. The issue was where the structure made contact with the ground.
If the connection to the ground is wrong, nothing above matters.
We understand this intuitively with buildings, yet we seem to completely ignore it with the most complex system we will ever own: our bodies.
As the British weather begins to turn milder and we head into running season, hundreds of thousands of individuals are about to go trainer shopping. Most will make a decision based on colour, a friend’s recommendation, or a vague loyalty to a brand they’ve always worn, or one that signals being part of the crowd. They treat shoes like an accessory.
But our choice is shoe is not an accessory. It’s a foundation. And just like the Citicorp Centre building, if the foundation is off by a few degrees, the stress doesn’t stay at the bottom. It travels up. It impacts the walls all the way up on the 50th floor.
For the last decade or so, I’ve privately recommended a specific document for any running clients looking for the answer to the question “What shoe should I buy?”… It’s the Hruska Clinic Shoe List. It’s not a list of “cool” shoes. It’s designed as a rigorous, biannually updated audit of structural integrity. It teaches us a lesson that applies as much to psychology as it does to physiology: You cannot fix a problem if you’re standing on unstable ground.
The Ascending Influence
There’s a concept in biomechanics called “ascending influence.”
Imagine you’re standing in a room. The floor underneath your left foot suddenly tilts forward, your ankle rolls to catch you. Then your shin rotates. Your knee caves inwards slightly to compensate. Your hip drops. Your spine curves to keep you upright. Finally, your neck tilts so your eyes stay level to the horizon.
A shift of only a few millimetres at the floor caused a kink all the way up in your neck. From the floor all the way to the cranium, everything is connected.
When you run, you hit the ground with two to three times your own bodyweight. If your shoe is unstable, your body has to spend the energy fighting that instability before it can even consider moving forward.
We often wonder why we have headaches, lower back pain, or tight shoulders. We stretch, we take painkillers, we buy ergonomic office chairs. We spend all our time trying to fix the roof, ignoring the fact that the floor underneath us has shifted.
The Psychology of the “Bad” Shoe
Why do we buy bad shoes?
I’m not saying anyone goes out with the deliberate intention to buy a bad running shoe, but we can look to behavioural science for a few simple cues as to why we end up doing so. One is Social Proof. If we see an elite-level marathon runner wearing essentially a carbon-plated neon slipper, we assume that’s what we need. We confuse the concept of performance with health.
An F1 car has tyres designed to go as fast as possible for an hour or so, then be thrown away. You wouldn’t put the same tyres on your Volkswagen Golf to drive the kids to school. Yet we buy “F1” shoes for our “VW” bodies and wonder why we break down.
Another is the Sunk Cost Fallacy of brand loyalty. “I’ve always worn “X” brand,” we say. But shoe companies are businesses first and foremost. We shouldn’t forget that. They change manufacturers, foams, and designs every year to save on costs or to chase emerging trends. A model that was perfect in 2024 might be structurally compromised in 2025.
I used to love recommending the New Balance 1080 back in its V10 days. Now at V15, I’m not even sure I could even call it the same shoe.
This is why the Hruska Shoe List has always been such a fascinating tool. It doesn’t pledge allegiance to a logo or brand. It looks at the shoe’s physics in the current moment, model to model. Sometimes a shoe has sat on the list for 3-5 years; sometimes it gets dropped because the new model has lost the integrity that the previous offered.
It treats shoes like an individual stock portfolio. Past performance is absolutely no guarantee of future results. You have to look at the fundamentals in the now.
The Non-Negotiables
The Hruska Clinic recommends shoes based on how they allow the body to sense the ground beneath it and maintain a “neutral” position. While “neutral” can be a loaded term in fitness, the criteria are deceptively simple.
Here are the three main things which you can test in-store in about ten seconds.
The Heel Counter (The Anchor): Squeeze the back of the shoe (the part that cups your heel). If should be stiff. It shouldn’t collapse under pressure. It should be even, without directional tilt.
If the heel is soft, your calcaneus (heel bone) will shift around. If your heel is shifting, your brain doesn’t know where the ground is beneath your. And if your brain doesn’t know where the ground is underneath you, it tightens things up (eg., muscles) to prevent you from falling.
The Flex Point (Natural Motion): Hold the shoe at the heel and toe, and push them together. The shoe should bend at the toe box—where your toes actually bend.
If it bends in the middle (at the arch), rethink your choice. A shoe than bends in the middle offer now leverage to move your through the required motion for normal gait (walking) mechanics.
Sensory Input (The Feedback Loop): This is often the most subtle and most human element. The list prioritises shoes that allow you to “sense” the ground underneath you through your heel, arch, and big toe. Shift your bodyweight to one side, pick up the other foot. Can you sense the ground through your heel, arch, and big toe? On both sides? Evenly?
We live in an era of “max cushioning.” We want to walk on clouds. But walking on clouds is a sensory deprivation tank for your feet. We feel nothing. When you can’t feel the floor, your body loses its sense of balance. You want a shoe that protects you from the miles spent pounding into concrete, but still keeps you aware that there’s something solid beneath you that you can push against.
Comfort is Honest
Having referenced the Hruska list for a decade and studied the science, there’s a line I’ve heard tens of times through the years, “Shoes should feel comfortable right away. You shouldn’t have to break them in.”
This is a profound life lesson essentially masquerading as shoe advice.
How often do we stick to things—jobs, relationships, diets—that feel painful, telling ourselves pretty much the same thing, that we just need to “break them in”? We equate suffering with progress. We think if it hurts, it must be working.
But the body knows. If a shoe fights against you in the shop, it will fight you on the pavement too. If you have to tie the laces so tight your foot goes numb just to keep your heel from shifting around, the geometry is off.
The Lesson Learned
The reason I’ve recommended this list for a decade or so at this point isn’t just because its choices may prevent shin splints. It’s because it forces a shift in perspective.
If forces you to stop looking at the flashy new upper mesh, or the recycled colour-way from a few years ago, and starts you looking at the boring rubber sole, the build of the shoe, how it directs the flow of movement through the foot. It forces you to prioritise function over fashion. It forces you to respect the ascending influence—to understand that small things at the bottom dictate the big things at the top.
In fitness, as in finance or relationships, we’re obsessed with the “cranium”—the visible results, the high returns, the glory. We very rarely think about the “floor”—the stance we’re in, the tiny daily habits that compound, the elements that keep us stable.
But you can’t fire a cannon from a canoe.
As we head towards a new running season, check your foundation. Find a shoe that holds your heel, bends where you bend, and lets you feel the ground beneath you. Respect the floor. The view from the top’s much better when you aren’t worried about the ground beneath you crumbling.
AK.