# Kinematic Analysis of Daily Activity of Touching Lateral Shoulder for Normal Subjects
## 3 Results
### Joint Angle for Different Groups
\begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Kinematic Variable/Age (SD)** & **20–29** & **30–39** & **40–49** & **50–59** \\ \hline
**Movement times (s)** & & & & & \\ Lifting & 0.8 (0.1) & 0.8 (0.1) & 0.6 (0.1) & 0.9 (0.1) \\ Resting & 0.5 (0.1) & 0.5 (0.1) & 0.5 (0.1) & 0.7 (0.2) \\ Returning & 0.8 (0.1) & 0.7 (0.1) & 0.7 (0.1) & 0.8 (0.0) \\ Total movement times & 2.1 (0.3) & 2.0 (0.2) & 1.8 (0.2) & 2.4 (0.2) \\ \hline
**Joint angle (\({}^{\circ}\))** & & & & \\ _Shoulder_ & & & & \\ Lifting (horizontal adduction) & 39 (1.9) & 36 (2.5) & 37 (1.3) & 45 (3.3) \\ Resting (cross-body adduction) & 49 (2.6) & 44 (3.6) & 40 (3.2) & 53 (3.6) \\ Returning (abduction neutral) & 34 (2.4) & 30 (1.3) & 29 (1.9) & 36 (3.3) \\ _Ellow_ & & & & \\ Lifting (minimum flexion) & 69 (2.9) & 64 (3.7) & 70 (2.9) & 79 (3.4) \\ Resting (flexion) & 55 (1.4) & 50 (4.7) & 56 (2.5) & 60 (2.6) \\ Returning (extension increase) & 72 (3.8) & 70 (4.7) & 74 (5.6) & 84 (4.3) \\ _Wrist_ & & & & \\ Lifting & 160 (1.7) & 155 (1.4) & 158 (0.6) & 154 (2.2) \\ Resting & 165 (0.9) & 166 (0.9) & 164 (1.5) & 164 (1.5) \\ Returning & 159 (2.0) & 153 (1.2) & 153 (0.8) & 154 (1.3) \\ \hline
**Peak velocity (PV) (m/s)** & & & & \\ _Elbow_ & & & & \\ PV for lifting & 0.45 (0.04) & 0.49 (0.09) & 0.44 (0.10) & 0.49 (0.05) \\ PV for returning & 0.38 (0.08) & 0.44 (0.19) & 0.40 (0.14) & 0.39 (0.06) \\ Time to PV in lifting (s) & 0.25 (0.09) & 0.25 (0.05) & 0.23 (0.04) & 0.31 (0.08) \\ Time to PV in lifting (\%) & 34.25 (7.75) & 37.61 (10.0) & 32.24 (7.46) & 38.19 (8.87) \\ \hline
**Joints Coordination** & & & & \\ _Pearson Correlation Coefficients_ & & & & \\ Lifting & 0.998 ** & 0.985 ** & 0.997 ** & 0.944 * \\ Returning & 0.997 ** & 0.967 ** & 0.986 ** & 0.950 * \\ \hline \hline \end{tabular}  
* \({}^{\blacksquare}\) Correlation is significant at the 0.01 level (2-tailed).
* \({}^{\blacksquare}\) Correlation is significant at the 0.05 level (2-tailed).  
\end{table} 
Table 3: Kinematic variables for normal subjects by age groups. differences existed for the mean angle of the shoulder joint for the whole task between the 30s and 40s age groups compared to the 20s and 50s age groups. Meanwhile, significant differences between the mean angle existed for the elbow joint during lifting between the 30s age group and the 50s age group. Post hoc tests for wrist joint mean angles showed a significant difference between the 20s age group and the 50s age group during the lifting and returning phases. This was due to the wrist joint angle producing little difference in wrist joint movements during the resting phase. Thus, the movements of the hand and arm segments were treated as one segment. Differences between the maximum and minimum for the shoulder and elbow joint angles were calculated as shown in Table 4. For the differences between maximum and minimum values of the shoulder joint angle, a significant difference of the mean angle was found between the 30s and 40s age group compared with the 50s age group. Meanwhile, for the difference between maximum and minimum values of the elbow joint angle, a  
Figure 4: Angles for shoulder and elbow during touching of contralateral shoulder for normal subject. significant difference was shown for the mean angle between the 20s and 40s age groups compared with the 50s age group.