🏋️‍♂️ Sport Exercise Tracker Widget #

A Flutter package that provides a ready-to-use camera-based exercise tracker widget.
It allows developers to integrate real-time exercise tracking using the camera 🎥 and provides automatic repetition counting with visual feedback 📊.

Perfect for fitness apps, personal trainer apps, or any app that wants to guide users through exercises safely and interactively.

✨ Features #

• 🎥 Real-time camera preview (front/back)
• 🤖 Pose detection using keypoints (shoulders, elbows, knees, hips…)
• 🔄 Automatic repetition counting using state machine architecture for mouvement sequence detection.
• 🎚️ Configurable difficulty levels (easy, medium, hard) and exercise types (squat, biceps curl, leg raise, lateral raise)
• 👀 Visual feedback: keypoints, connecting lines, angles, repetition counter
• 🎨 Adjustable UI styles (colors, line thickness, circle radius, angles text)
• 🚫 Works offline — no external servers required

🧠 How It Works (Algorithm & Logic) #

The widget uses pose keypoints & angle calculations to detect exercises accurately. Main workflow:

1. Pose Detection 🤳

   • Captures camera frames in real-time.
   • Detects keypoints for joints (shoulders, elbows, knees, hips, etc.).

2. Angle Calculation 📐

   • Calculates specific joint angles per exercise.
   • Examples:
     • Curl → elbow angle
     • Squat → knee & hip angles
   • Angles determine start & end positions of each repetition.

3. Difficulty Level Adjustment 🎯

   • Each level applies a threshold angle offset.
   • Higher difficulty → stricter angle requirement to count a repetition.

4. Timing Filter ⏱️

   • Ensures natural movement duration.
   • Prevents false positives from fast, jerky, or random movements.

5. Repetition Counting 🔢

   • Counts a rep when:
     1. Angle reaches start threshold (minRequiredAngle - Difficulty_Offset)
     2. Then reaches end threshold (minRequiredAngle + Difficulty_Offset)
     3. And timing constraints are satisfied
   • Sends real-time callback via onRepsRepetitionCount.

6. Visual Feedback 👁️

   • Draws keypoints on camera feed
   • Connects joints with lines for better guidance
   • Optional angle labels for user reference
   • Repetition counter shown on screen

🚀 Usage Example #

import 'package:sport_exercise_tracker_widget/camera_sport_exercise_tracker_widget.dart';

CameraSportExerciseTrackerWidget(
  cameraConfig: CameraConfig(cameraDirection: CameraLensDirection.front),
  exerciseName: ExerciseName.curl,
  enableExerciseRepsCounting: true,
  resetExerciseRepsCounting: false,
  difficultyLevel: ExerciseDifficultyLevel.medium,
  showKeypointCircles: true,
  showKeypointLines: true,
  showAnglesText: true,
  onRepsRepetitionCount: (reps) {
    print("Reps counted: $reps");
  },
);

🧩 Exercise Tracker Functional Diagram:

🎬 Check the video demo here Video Demo #

🔧 What’s Next / To Be Improved #

1. Separation of Concerns #

Currently, ExercisePosePainterWidget calculates angles and counts repetitions.

Planned improvement: move the calculation logic to a parent widget and inject only the calculated angles and rep counts into the painter. This will make the widget cleaner and easier to maintain.

2. Add More Exercises #

Currently, 4 exercises are implemented. You can easily add more exercises based on your needs.

To add an exercise:

1. Add the exercise in models/exercises.dart
2. In enums.dart, define its minRequiredAngle and offsetAngles
   And That’s it 😀, the new exercise will be available in the dropdown selector in the example code.