About Push-up and Plank Coach

Push-up and Plank Coach counts your push-ups and times your planks from your camera, and checks them against clear, measurable rules. A push-up counts only on a complete down-then-up cycle: chest to the down line, arms to full lockout, straight body line. A plank banks good-form seconds only: the clock pauses whenever your line breaks. Nothing ever leaves your device.

How it works

• Your camera looks at you from the SIDE. The app tracks your body joints (shoulders, elbows, wrists, hips, knees, ankles, nose) with the MediaPipe Pose Landmarker, running entirely in your browser. No video is sent anywhere.
• Set your start position first. Hold the top plank position, straight line from head to heels, and press Set start position. The app measures your shoulder height, torso length and body length from that hold, and scales every threshold to your body and your distance from the camera. Re-measure any time in a lesson or in Settings.
• Each video frame is turned into a few numbers: how far your shoulders have dropped from the start height, your elbow angle, how far your hips sit from the shoulder-to-ankle line, and how far your nose sits below your shoulders. Those numbers are checked against the rules below.
• Feedback is one named hint at a time, within about a second: Go lower, Lock out at the top, Hips sagging, Hips piked, Head dropped. A rep with a fault in it counts but is not clean; a rep that never reaches the down line or never locks out is rejected with the named reason.
• The camera is only on while you are in a lesson. It turns off when you go back to the exercise list, press Turn off, or switch to another tab.

The rules

• Down: shoulders drop at least 35% of torso length from the start height, AND elbows bend to 140 degrees or less.
• Up (lockout): shoulders return to within 12% of torso length of the start height, AND elbows open to 160 degrees or more.
• Straight line: hips stay within 10% of body length of the shoulder-to-ankle line. More than 10% below the line is sagging; more than 10% above it is piked.
• Head: nose stays within 18% of torso length below the shoulders. Lower than that is a dropped head.
• Push-up counting: a rep counts only on a complete down-then-up cycle. Coming part-way down and back up is rejected as a half rep ("Go lower"). Coming all the way down and back up without straightening the arms is rejected as no lockout ("Lock out at the top").
• Plank timing: good-form seconds accumulate only while no form fault is present. Total elapsed time keeps running separately, so you can see how much of your hold was clean.
• Not seen, not counted: if the app cannot see your head, hips and ankles clearly, it says so instead of guessing.

Levels, workouts and quizzes

• Push-up levels: Knee push-ups (open), Standard (50 points), Wide (150 points), Decline (300 points). Every level uses the same down-and-lockout rule.
• Plank levels: Front plank (open), Side plank (150 points). Same straight-line rule, viewed from the side.
• Workouts: Push-up sets (3 x 8), a quick set of 10, Plank holds (3 x 20 good-form seconds), a 60-second hold. Only clean reps count toward a set.
• Quizzes: 5 clean push-ups, or a 20-second clean plank. Passing a quiz is +20 bonus points and the Quiz Passed badge.
• Points and levels: +10 per clean rep, +1 per good-form plank second. Levels: First Rep, Getting Strong, Solid Core, Plank Master. Badges: First Clean Rep, First Plank Hold, Perfect Set, Sixty Seconds, 7-Day Streak, Quiz Passed. Confetti and chimes celebrate wins and can be turned off in Settings.

What it cannot see

• The app needs a side view. From the front it cannot tell how low your chest goes, so it will not count reps.
• Loose clothing, poor light, a cluttered background, or another person in frame can confuse the pose tracker. If it cannot see you clearly, it says so.
• The app does not check hand placement, breathing, speed, or how the exercise feels. It does not know if you are injured, tired, or in pain. Stop if anything hurts.
• Pose tracking is approximate. A rep the app counts may not be perfect, and a rep it rejects may have been fine. The rules are the authority inside the app; a real instructor is the authority outside it.
• Fitness-instructor review sought: we are seeking review of this app by fitness instructors and PE teachers, in parallel with its release. Review is not a gate: the app is live while review is sought, and corrections will be folded in as they arrive.

Learn more

These links open other websites in a new tab. Push-up and Plank Coach is not affiliated with any of them and sends them nothing.

Privacy

• Your video never leaves your device. It is analysed in your browser frame by frame and immediately discarded. Nothing is recorded, uploaded or shared.
• No accounts, ads, cookies, analytics or trackers. The app loads nothing from other websites: the code is served from this site, and a security policy blocks connections anywhere else.
• Stored on your device only: which items you have tried, your points, badges, practice days and settings, your start-position calibration, and whether you have seen the welcome message, in your browser's local storage. Clear it any time in Settings → Clear progress, or with the Offline proof → Delete all my data button, or by clearing this site's data in your browser.
• Offline copy: after your first visit, your browser keeps a copy of the app so it works offline. Clearing site data removes it.
• The camera is only on while you are in a lesson. It turns off when you go back to the exercise list, press “Turn off”, or switch to another tab.
• Hosting: like any website, the server that delivers the app's files may keep standard technical logs (such as IP addresses) of those downloads. The app itself sends nothing.
• Reference links go to other websites, which have their own privacy policies.

Disclaimer

• This is a home practice tool, not a teacher, therapist or safety device. Everything runs on your device: no video, audio or images are sent anywhere. Feedback is automatic and can be wrong. For real instruction, learn from a qualified fitness instructor or PE teacher, linked on the Resources page.
• Not a fitness assessment. Stop if anything hurts. Follow school safety rules. Clear the floor around you, warm up first, and rest between sets. If you have a health condition, an injury, or pain, check with a doctor or qualified professional before exercising.
• The app is provided “as is”, without warranty of any kind.

Accessibility

• Everything works with a keyboard. Feedback is announced to screen readers, and animations follow your device's “reduce motion” setting. Sound and confetti can be turned off in Settings.
• The live check depends on a camera and on moving on the floor. If that does not work for you, the rules, levels, workout descriptions and reference links still work on their own.

Credits

• Pose tracking: MediaPipe Pose Landmarker (lite), Apache 2.0, bundled with the app. See THIRD_PARTY_NOTICES.md.
• The form rules (down depth, lockout, hip line, head line) are original to this app and documented above.
• Reference links: ACE Fitness and Wikipedia, linked, not embedded.
• Built with the on-device coach pattern from the Little Hands app.

Push-up and Plank Coach version 1.0.0