Original research
Our data · 2
Illustration: FlappBike Position · 6 minKona Pros Don't Sit Higher. They Sit Further Forward.
We measured 31 pros and 68 age-groupers at the Ironman World Championship 2026. Their knees at the bottom of the stroke were the same. Their hips over the crank were not: the pros sit about 3° — 4–5 cm — further forward, men and women alike.
Photo: Scott Flathouse (@scottflathousephoto)Bike Aerodynamics · 8 minKona 2026: What 32 Pro Bike Positions Actually Measure
We measured thirty-two professional triathlon positions from the Ironman World Championship, men's and women's, and checked every joint point by hand. Hands are up, torsos are not as low as you think, and a closed shoulder is a choice. The numbers, and what an age-grouper should take from them.
Running form
Guides · 6
180?Étienne-Jules Marey, 1883 · public domainRunning Form · 8 minRunning Cadence: Why 180 Isn't a Magic Number
What running cadence actually is, how it changes the forces on your body, and how to raise it safely without wrecking your form — the evidence behind the '180 spm' rule of thumb.
Étienne-Jules Marey, 1883 · public domainRunning Form · 7 minTrunk Lean: Run Tall, Not Folded
How much your torso should lean when you run, why an upright trunk is more economical than folding at the waist, and where the lean should actually come from — the evidence behind good running posture.
Flapp footage · 60 fpsRunning Form · 9 minFoot Strike: Heel, Midfoot, Forefoot — and Why It's Not the Whole Story
The honest version of the foot-strike debate: what heel, midfoot, and forefoot landing actually change, why 'switch to forefoot' is bad advice on its own, and what your strike is really telling you about the rest of your form.
+0 · +50 · +100 · +150 · +200 msFlapp footage · 60 fpsRunning Economy · 7 minGround Contact Time: How Long Your Foot Stays Down — and Why It Matters
What ground contact time measures, why less time on the ground usually means more efficient running, and how it's really a mirror of your cadence and landing rather than something to train directly.
Flapp footage + Flapp overlayRunning Form · 8 minOverstriding: The Braking Force Hiding in Your Stride
What overstriding actually is, why a foot that lands ahead of your hips brakes you on every step, and the simple cadence-and-posture fixes that pull your landing back underneath you — with the biomechanics behind it.
Flapp footage · 7 framesRunning Economy · 7 minVertical Oscillation: The Bounce That Costs You Nothing to Fix
Why bouncing up and down wastes energy that could move you forward, how much vertical movement is normal, and the simple cue-and-cadence changes that flatten your stride — the evidence on running's most visible inefficiency.
Bike position and aero
Guides · 3
18852026É.-J. Marey, c. 1885 · National Gallery of Art, CC0 · Flapp footageBike Aerodynamics · 8 minAero Position: Where Your Speed Actually Hides
At racing speed most of what slows you down is your own body, not your bike. Here is what the wind-tunnel evidence says about torso angle, CdA and how much a better position is really worth.
Flapp footageBike Position · 10 minCleat Position: What the Research Actually Says
Fore-aft, rotation and stance width — a practical, evidence-based guide to setting up your cycling cleats. What the studies show about foot pain, economy and the triathlon myth, and how to change position without wrecking your fit.
165 mmFlapp footageBike Position · 9 minShort Cranks: Why the Pros Went 165 mm (and It Isn't About Your Legs)
The short-crank trend that swept the 2025-26 pro peloton isn't about leverage. It's a fit change that opens your hip angle, lets you get lower, and helps you breathe — here's the evidence and how to switch without wrecking your position.
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