What a video gait analysis tells you
A gait analysis looks at how a runner moves from head to toe. It helps you spot the habits that waste energy or put extra stress on the body, often before they turn into an injury.
At full speed, most of those habits are invisible. A foot that lands too far ahead of the body or a hip that drops on every stride happens in a fraction of a second. Video lets you pause on the exact frame and show the runner what you’re seeing.
This guide walks coaches and physical therapists through a video gait analysis step by step. It starts with filming and then moves through what to look for from each angle.
If a runner has pain, a gait analysis is a starting point, not a diagnosis. Refer them to a physical therapist or sports medicine provider.
Step 1. Set up your cameras
A good analysis depends on good footage. If the setup changes every session, you can’t compare one video to the next.
Treadmill or outdoors. A treadmill keeps the runner in one spot, so it’s easier to film several strides from a fixed camera. Running outside on a track or path is more natural, but you’ll need a longer stretch and a wider frame. Many coaches use the treadmill for a detailed look and outdoor runs to confirm what they saw.
Camera angles. Film from the side, the front and the back. The side view shows foot strike and posture. The front and back views show what the knees and hips are doing. Filming all angles at once with more than one camera saves time and keeps every view in sync.
Camera height and distance. Set each camera at about hip height, square to the runner. Pull back far enough to keep the whole body in frame, head to feet, for several strides in a row.
Frame rate. Film at 120 or 240 frames per second.
Before you record. Have the runner warm up for a few minutes so you see their normal stride. Ask them to wear fitted clothing so you can see the hips and knees. Then film at their easy pace and, if it matters for their goals, at race pace too.
Step 2. Break the stride into phases
A running stride repeats the same moments over and over. Pausing on the same moment each time makes faults easier to spot and easier to compare later.
- Initial contact. The first frame where the foot touches the ground. Check where the foot lands relative to the body and which part of the foot hits first.
- Midstance. The point where the body passes over the foot and takes the most load. This is where knee collapse and hip drop usually show up.
- Toe-off. The last frame before the foot leaves the ground. Look at how far the hip extends behind the body.
- Swing. The leg travels forward to the next step. Watch the path of the foot and whether it swings out to the side.
Use frame-by-frame playback to find each moment. Then save or screenshot that frame so you can compare it in the next session.
Step 3. What to check from the side
The side view is where most of the big-picture issues show up. Start here.
Foot strike. At initial contact, note whether the runner lands on the heel, midfoot or forefoot. No single pattern is right for everyone. What matters more is where the foot lands.
Overstriding. Draw a vertical line up from the point where the foot touches down. If the foot lands well ahead of the knee and hips, the runner is overstriding. This acts like a brake on every step and puts more load on the knee and shin.
Knee bend at midstance. A soft, bent knee absorbs the landing. A knee that stays nearly straight sends more of the impact up the leg.
Posture. Look for a slight forward lean from the ankles, with the head and torso stacked. Bending at the waist or leaning back are both worth noting.
Arm swing. The arms should swing forward and back from the shoulders, with the elbows bent. Arms that cross the body or barely move can throw off balance.
Bounce. Watch the head against a fixed point in the background. A lot of up-and-down movement often means energy is going up instead of forward.
Step 4. What to check from the front and back
The front and back views show side-to-side movement you can’t see from the side. Small differences between the left and right leg matter here, so check both.
Knee alignment. At midstance, draw a line from the hip down through the knee to the ankle. A knee that collapses inward is called valgus. A knee that bows outward is called varus. Either one changes how load moves through the joint.
Hip drop. From behind, watch the pelvis while one foot is on the ground. If the hip on the opposite side dips, it often points to weak hip muscles on the standing leg. A horizontal line across the hips makes this easy to see.
Crossover. Watch where each foot lands. If the feet land on or across the center line, like running on a tightrope, the runner is crossing over.
Foot and ankle. From behind, look at how much the ankle rolls inward after landing. Some rolling is normal. A lot of it, or a big difference between feet, is worth a closer look.
Shoulders and arms. Check that the shoulders stay level and both arms swing the same way. Uneven arm swing can point to an imbalance lower in the body.
Step 5. Measure and compare over time
One video shows you where a runner is today. A series of videos shows whether your coaching is working.
Count cadence. Count how many times one foot hits the ground in 30 seconds, then multiply by four to get steps per minute. Many coaches use roughly 170 to 180 as a loose guide, but the right number depends on the runner’s height and speed. A low cadence often goes hand in hand with overstriding.
Measure key angles. Use an angle tool on the same frame each session, such as knee bend at midstance or shin angle at contact. A number gives you and the runner something concrete to track.
Compare side by side. Put two videos next to each other to see change. Common comparisons include:
- Before and after a block of training, to show progress
- Shoes on and barefoot, to see how footwear changes the stride
- The runner next to an experienced runner with a similar build, to set a clear target
- Left leg next to right leg, to spot an imbalance
Film from the same spots each time. Otherwise, a change in the video might just be a change in the camera.
Common gait faults at a glance
Use this as a checklist while you step through the video.
| Fault | What you’ll see | Best view | When to pause |
|---|---|---|---|
| Overstriding | Foot lands well ahead of the knee and hips | Side | Initial contact |
| Straight-knee landing | Little knee bend as the foot takes load | Side | Midstance |
| Too much bounce | Head moves up and down a lot | Side | Whole stride |
| Knee collapse (valgus) | Knee drifts inward past the hip-to-ankle line | Front | Midstance |
| Hip drop | Opposite hip dips while one foot is down | Back | Midstance |
| Crossover | Feet land on or across the center line | Front or back | Initial contact |
| Excess ankle roll | Ankle rolls far inward after landing | Back | Midstance |
| Arm crossing | Hands swing across the center of the body | Front | Whole stride |
Tools that make video gait analysis easier
You can do a basic gait analysis with any phone camera. The right app makes it faster and gives you more to work with.
Skeleton tracking. Onform’s skeleton tool lays a joint overlay on the runner, so you can follow knee and hip angles through the whole stride without drawing them by hand. Our skeleton tracking guide shows how it works.
Drawing tools. Ten drawing tools let you mark up the frame itself. Use them to draw the hip-to-ankle line or measure knee bend at midstance.
Frame-by-frame playback. Step through a stride one frame at a time to find initial contact and midstance exactly.
Multi-cam recording. Film the side and back views at the same time, so every angle lines up with the same stride.
Side-by-side comparison. Put two videos next to each other to show progress or compare left and right.
Frequently asked questions
Can you do a gait analysis with a phone?
Yes. Most modern phones film in slow motion, which is enough for a useful gait analysis. A tripod and a consistent setup matter more than the camera itself.
Should I film on a treadmill or outside?
Both work. A treadmill makes it easier to film many strides from a fixed spot. Running outside shows the runner’s natural stride. If you can, start on the treadmill and confirm what you find with an outdoor run.
What’s the difference between a walking and a running gait analysis?
The process is the same, but the details change. Running has a moment where both feet are off the ground, and the landing forces are much higher. Physical therapists often look at walking gait for rehab, while coaches usually focus on running.
How often should you repeat a gait analysis?
A good rhythm is every four to eight weeks during a training block, or after a change in shoes or training load. Film the same way each time so you can compare the videos.
Start your first video gait analysis
A phone on a tripod and the checkpoints above are enough to get started. Film from the same spots each session, and you’ll build a clear record of how each runner changes over time.
To try it with Onform, download the app and start a free 14-day trial. No credit card required. Or schedule a demo and we’ll show you how coaches and physical therapists use it for gait analysis.