Two-Week Check-in #6: Walking vs Running

Yo! 👋

Say you just got into running and want a new pair of running shoes. You walk into Running Room, the sales associate tells you to walk 10 steps across a foot pressure plate or a foot scanner, and based on those 10 steps they determine the best shoe for you. So what's the point of Mylz? → That was a couple runners' first reaction when we told them what we're building this week.

Well, here's the thing: walking is not running. It's NOT the same movement at different speeds, it's an entirely different movement. We found that out with our own hardware, and the literature backs it up.

When you walk, you're basically a moving pendulum. One foot is always on the ground, and for about 20% of every step both feet are down at once. Think of it as vaulting over a stiff leg. (source: USPTO)

When you run, you're a bouncing spring. There's a flight phase where neither foot is touching the ground at all, and the leg loads and recoils like a spring instead of a pendulum. The muscles even fire in a different pattern. (source: American Physiological Society)

And the big one: walking lands you around bodyweight, running can spike vertical ground reaction forces up to ~3x bodyweight. Your foot strike often shifts too (heel when walking → mid/forefoot for a lot of runners). (source: Freedom Clinics)

So here's the punchline 🥁

When a store has you walk a few steps to "test" a shoe, they're measuring the wrong sport. A walk can't show the flight phase, can't show how you land at 3x bodyweight, can't show what your shoe does under actual running load.

It's like test-driving a Porsche 911 GTS by rolling it through a parking lot. You learn that it goes straight (no shit), it turns (it better), the brakes work (WOW!). You learn nothing about how it holds a line through a fast corner, whether the tires actually grip when you push them, or if it stays planted at top speed instead of getting twitchy under hard braking. Everything that defines the engineering, the stuff you actually bought it for, only shows up on the circuit, the sport that it's meant for. The parking lot hides every nuance that matters. A walk test does the exact same thing to a running shoe.

Which is why what we do is a bit more scientific than what Running Room does (oh, we competing 😏).

Taking it to the labs 🔬

Our goal is to provide the most accurate data within our hardware, with algorithms backed by science. So we've been reaching out to kinesiology profs across Canada to pressure-test our metrics against gold-standard lab equipment, and the response has been better than we hoped.

• York University (as seen above) got back to us fast and we had a great hour-long call. We've tentatively booked time in their motion-capture lab in August to collect ground-truth data we can tune our algorithms against.
• McGill hopped on a call and has already been generous with feedback, connecting us with their PhD students for support and steering us toward bilateral asymmetry as the metric to lead with. Which lines up perfectly with our two-tags-per-pair setup.
• U of T and U Calgary are scheduled for next week.

None of this is us claiming a stamp of approval (we're way too early for that). It's us doing what we know to make sure that when our product says "your left side is working 8% harder than your right," or "your shoe has degraded 5%," that number is backed by reality.

More soon. Go run outside, your gait will thank you.

Keep logging mylz, ✌️ Brian