Skip to main content

Table 4 Predictions of range of amplitude of trapezius muscle activity and range of motion shoulder, head, neck, and torso postures

From: Prediction of trapezius muscle activity and shoulder, head, neck, and torso postures during computer use: results of a field study

Range of Amplitude/Range of Motion Task-based predictions Expanded model predictions1
R2 RMS Relative RMS R2 RMS Relative RMS
Shoulder EMG (%MVC)       
Right Trapezius 0.00 4 18 0.40 3 10
Left Trapezius 0.00 4 16 0.43 4 13
Shoulder Posture (degrees)       
Right Abduction 0.02 9 16 0.36 8 13
Left Abduction 0.02 8 17 0.35 7 15
Right Flexion 0.02 8 16 0.39 7 14
Left Flexion 0.01 10 19 0.41 8 16
Right Internal Rotation 0.00 21 30 0.22 14 20
Left Internal Rotation 0.04 15 23 0.36 14 21
Head Posture (degrees)       
Tilt 0.00 10 14 0.41 7 9
Flexion 0.03 22 35 0.39 9 14
Neck Posture (degrees)       
Tilt 0.01 3 16 0.33 3 14
Flexion 0.05 7 16 0.42 6 13
Torso Posture (degrees)       
Tilt 0.01 16 42 0.34 4 10
Flexion 0.02 11 29 0.30 8 20
  1. 1R2, RMS, and Relative RMS are the average values from jackknifed calculations.
  2. Comparison of task-based and expanded model predictions based on R2 values, RMS errors, relative RMS errors.