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The dimensions of running form and bike fit we measure on every video. Each page explains what we're looking at, why it matters, and how to fix it when it's off.

Want the full picture of how grading works? Read the methodology →

Running form

Posture & Lean

How forward (or backward) you lean from the ankles while running.

3–12° forward lean

Overstriding

Landing with your foot ahead of your hips creates a braking force every step.

<20% of frames landing ahead of hips

Vertical Oscillation

How much your body bounces up and down each step.

<6 cm bounce per stride

Hip Drop

The non-stance hip dropping below level — a sign of weak glute medius.

<2% left-right asymmetry

Arm Swing

Symmetric arm swing balances your stride and helps drive cadence.

>85% symmetry

Knee Mechanics

Knee flexion at stance — too straight means braking, too bent means quad-dominant.

140–165° average knee flexion

Foot Strike

Heel, midfoot, or forefoot — what part of your foot hits the ground first.

No fixed target — context for overstriding

Shank Angle at Contact

Whether your shin is vertical when the foot touches down — the clinical overstriding tell.

Within 5° of vertical at contact

Overstride Reach

How many centimeters ahead of your hips the foot lands at contact.

Under ~20 cm ahead of the hips

Knee Flexion at Contact

How much bend your knee has when the foot touches down (~20° is the clinical norm).

15–25° of knee bend at contact

Knee Flexion at Midstance

How deep the knee loads when your body passes over the planted foot (~40° is ideal).

35–45° of knee bend at midstance

Ankle Dorsiflexion

How far your shin travels forward over the planted foot at midstance.

15–25° of forward shin travel at midstance

Hip Extension at Toe-off

Whether your stride finishes behind your body — where propulsion actually comes from.

≥10° of thigh extension past vertical at toe-off

Ground Contact Time

How long each foot spends on the ground, and whether left and right match.

<280 ms at easy pace; 49-51% L/R balance

Cadence

Your step rate — the single most powerful lever over the rest of your form.

170–190 spm at easy-to-steady pace

Bike fit

Saddle Height

Your knee extension angle at the bottom of the stroke — the single most important fit measurement.

30–40° of knee bend at the bottom (knee extension angle)

Knee at Top

How tightly your knee compresses at the top of the pedal stroke.

~105–115° knee angle at the top of the stroke

Hip Angle

How open the angle between your torso and thigh is — the balance of power, comfort, and aero.

~45–55° torso-to-thigh angle (endurance)

Back Angle

How flat or upright your back is relative to horizontal.

~40–55° back angle from horizontal (endurance)

Elbow Angle

Whether your arms are softly bent (good) or locked out (harsh and twitchy).

~150–165° elbow angle (slight bend)

Hip Rock

How much your pelvis rocks side to side (vertically) on the saddle — the classic too-high tell.

<2 cm of vertical pelvis movement

Foot Angle (Power Phase)

Whether your foot is level when you're actually driving the pedal (3 o'clock).

0–12° toes-down in the power phase

Knee Over Pedal

Whether your knee stacks over the pedal spindle in the power phase — the fore/aft check.

Knee within ~2.5 cm of the forefoot at 3 o'clock

Get your grade across all 7

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