Evaluation of the teaching delivery methods on muscle activity

The purpose of this Ergonomic study was to evaluate different teaching delivery methods on muscle activity. The research was conducted on 30 subjects with 15 males and 15 females, none of them smoke and no one had undergone any surgery that limited their capability to perform the tasks. The subjects were evaluated while performing text writing, picture drawing and wiping on the blackboard, text writing and picture drawing on the easel and on the overhead transparency. A questionnaire was utilized to obtain the demographic and personal characteristics of the subject. A body discomfort survey was conducted before and after working with the above mentioned equipment. Body discomfort scores for different anatomical locations were recorded on a scale of 0-10, where 0 indicated no discomfort and 10 indicated severe discomfort. Working postures of the subjects were evaluated using the Rapid Upper Limb Assessment (RULA). The muscle activity of the subjects while performing the tasks was also recorded using an Electromyogram (EMG). From the data collected by EMG, mean values of the Root mean square (RMS) results were considered. From the data collected. Every task was evaluated and compared to other tasks. Correlation results concluded, that there is a significant relation between the Flexor muscle activity to the time taken for the task (r=0.67) but no significant correlation was established between demographics and RMS values or RULA scores (-0.6 > r < 0.6). ANOVA results of EMG data, RULA and body discomfort concluded that there is significant difference in the variances of different tasks for different muscle groups. Results of ANOVA revealed the blackboard is more strenuous for writing and drawing compared to the easel and the overhead transparency. The mean RMS values and ANOVA suggested wiping is more strenuous compared to writing and drawing on the blackboard. It was also concluded from ANOVA results that for any teaching delivery method, writing is more strenuous than drawing. Results obtained from descriptive statistics and ANOVA of EMG data concluded that performance on the blackboard can severely affect trapezius, anterior deltoid, lateral deltoid, posterior deltoid, flexors and extensors especially for wiping and text writing. Recommendations to alleviate these stresses were discussed.