Running form & gait analysis glossary

How many steps you take per minute while running.

Cadence is the number of foot contacts per minute (spm). Recreational runners typically sit between 160–180 spm at easy pace; elites tend to be 180+ at race pace. Higher cadence usually shortens stride length, reducing braking forces and overstride.

Distance covered between two consecutive contacts of the same foot.

Stride length is one half of the speed equation (speed = cadence × stride length). Reaching for stride length by overextending the lead leg causes overstriding; the better path is to lengthen the back side of the stride through hip extension.

Milliseconds the foot is in contact with the ground per step.

Recreational runners average 240–280 ms of ground contact at easy pace; elites are often below 200 ms at race pace. Shorter contact time correlates with better running economy and elastic energy return from the Achilles tendon.

Milliseconds both feet are airborne between contacts.

Flight time plus contact time defines the gait cycle. Excessive flight time relative to contact time often signals high vertical oscillation — bouncing instead of moving forward.

Ratio of ground contact time to total stride time.

Duty factor (GCT ÷ stride time) typically falls between 0.35 and 0.45 in distance runners. Lower values indicate a springier, more elastic stride; higher values indicate a grounded, shuffling stride.

Up-and-down movement of the center of mass per stride, in cm.

Healthy range is roughly 6–10 cm, or about 5–10% of body height. High oscillation wastes energy and increases impact loading. Raising cadence is the fastest fix.

Vertical oscillation divided by stride length, as a percentage.

A Garmin Running Dynamics metric that normalizes bounce against stride length. Lower is more efficient; sub-6% is considered very economical.

Which part of the foot first contacts the ground.

Roughly 75% of recreational runners are heel strikers. Foot-strike pattern alone does not predict injury — overstride relative to the hip does. See our deep dive on heel vs midfoot vs forefoot.

Landing with the foot well ahead of the body's center of mass.

Overstriding produces a braking impulse, raises vertical loading rate, and is the strongest modifiable risk factor for tibial stress fracture and patellofemoral pain syndrome.

Inward rolling of the foot through stance phase.

Some pronation is normal and helps absorb shock. Excessive pronation (overpronation) and insufficient pronation (supination) are gait deviations that should be assessed alongside hip drop and knee valgus, not in isolation.

Downward tilt of the swing-side pelvis during stance.

More than ~5° of pelvic drop in single-leg stance indicates weak gluteus medius. It is a top predictor of IT band syndrome and runner's knee, and is corrected with hip abductor strengthening.

Inward collapse of the knee during stance phase.

Knee valgus is driven by hip abductor weakness and ankle stiffness. It increases patellofemoral compression and is treated with hip and glute strengthening rather than knee-focused work.

Angle at the knee joint at the moment of foot contact.

A bent knee (around 140–155°) at strike absorbs impact. A near-straight knee (>165°) signals overstride and a high vertical loading rate.

How far the thigh travels behind the body in late stance.

Limited hip extension forces compensation through the lumbar spine or the opposite arm. Couch stretches and split-squat work restore range and add stride length without overstriding.

Angle of the torso from vertical at midstance.

A whole-body forward lean from the ankles of about 5–10° is associated with reduced knee loading. Lean from the waist (hinging) is a fault — it loads the lumbar spine and reduces hip extension.

How evenly the left and right arms swing through the gait cycle.

Asymmetric arm swing is usually a downstream marker of thoracic stiffness or hip flexor tightness. A symmetry score above 90 is excellent; below 70 warrants mobility work.

One full sequence from foot strike to the next strike of the same foot.

The gait cycle has a stance phase (foot on ground: initial contact, midstance, toe-off) and a swing phase (foot airborne: early swing, midswing, terminal swing). Running differs from walking by adding a flight phase with no foot in contact.

Computer vision technique that locates body joints in each video frame.

FormStride uses TensorFlow.js MoveNet to track 17 body keypoints (ankles, knees, hips, shoulders, elbows, wrists, ears, eyes, nose) per frame, then derives biomechanical metrics from their trajectories.

How quickly impact force builds at foot strike.

Vertical loading rate is associated with tibial stress fracture risk. Increasing cadence by 5–10% typically lowers loading rate without requiring a foot-strike change.

Oxygen cost of running at a given submaximal pace.

Better economy means less oxygen consumed at the same speed. Cadence, vertical oscillation, ground contact time, and elastic tendon return all influence economy.