Influence of Gender Differences on Range of Motion and Joint Angles During Eating in Young, Healthy Japanese Adults.

Objective: Eating is important in rehabilitation and is evaluated using joint angles that serve as kinematic information. Joint angles of the upper extremities during eating have been reported for men and for women; however, no study has investigated these joint angles in terms of gender differences. At present, no information is available on gender differences as individual factors of upper extremity joint angles during eating. Therefore, the present study investigated gender differences in upper limb joint angles during eating tasks involving a spoon or chopsticks.

Methods: We examined eating motions in 12 healthy Japanese men and 13 healthy Japanese women (aged 20-39 years) and compared the two groups. Motions were assessed using inertial sensors and three-dimensional motion analysis.

Results: We established, separately for men and women, the maximum angle and the range of motion (RoM) for each upper limb joint. Women generally had greater RoMs for all upper limb joints than men did. When subjects used a spoon, statistically significant differences and large effect sizes were observed for the maximum elbow joint flexion angle and the RoMs of the shoulder joint in abduction, flexion, and internal rotation. When subjects used chopsticks, statistically significant differences and large effect sizes were observed for maximum angles of shoulder joint internal rotation, elbow joint flexion, and wrist joint radial flexion and for the RoM of shoulder joint abduction.

Conclusions: We concluded that there are significant gender differences in upper limb joint angles during eating, and that these differences are influenced by numerous factors.