Table 4 Motion trajectory deviation analysis.
From: Fitness exercise evaluation system based on improved DTW algorithm
Movement type | Joints | Standard X-direction trajectory | User X-direction trajectory | X-direction deviation analysis | Standard Y-direction trajectory | User Y-direction trajectory | Y-direction deviation analysis |
|---|---|---|---|---|---|---|---|
Push-up | Elbow joint | Parallel arm movements | Outward or inward deviation of the elbow | May be caused by the imbalance of the pectoral muscles and shoulders, easy to increase the burden on the shoulders, affecting the stability of the movement | Vertical straight line push down vs. push up | Excessive bending or insufficient rise | Tends to increase stress on shoulders and elbows, leading to risk of injury |
Knee | Knees parallel to each other, avoiding internal and external rolls | Knee valgus or buckle | Affects the stability of the legs and increases the Figureure on the knees | Hold up | Too much bending | Affects core stability and reduces exercise effectiveness | |
Hip joint | Hip stabilizing movements from side to side | Hip has a side-to-side offset | Causes the body’s center of gravity to become unbalanced, affecting the overall trajectory of movement and increasing stress on the lower back | Maintaining a stable pelvic position | Hip instability from side to side | Causes excessive back flexion or hip instability that interferes with the natural curvature of the spine | |
Squat | Hip joint | Hip stabilizing movements from side to side | Excessive abduction or adduction of the hip | Affects the stability of the deep squat, resulting in an imbalance of force on the knee and ankle joints | Up-and-down stabilization | Forward leaning or excessive rise | Increased stress on knees, back |
Knee | Knees parallel to each other, avoiding internal and external rolls | Knee valgus or buckle | Uneven pressure on the knee joint, increasing the risk of injury | Vertical Squat and Rise | Hyperextension or hyperflexion | Strain or excessive compression of the knee | |
Chin-up | Shoulder joint | Knee valgus or buckle | One side rises too high or is offset | Excessive pulling up of one shoulder with incomplete cooperation of the other shoulder | Rising and stabilizing | Asymmetry in left and right shoulder motion | Shoulder asymmetry, affecting stability and efficiency of movement |
Elbow joint | Double Elbow Parallel Track | Excessive eversion or inversion on one side | Excessive valgus or valgus on one side of the elbow, resulting in asymmetric exertion | Uniformity of trajectory | Inconsistent left and right elbow offsets | Elbows turned out or in, affecting fluidity of movement |
