Estresse físico e psicofisiológico na desossa em frigoríficos bovinos e a macro pausa de descanso durante atividade

Abstract

Introduction: Muscle fatigue is a functional impairment caused by increased intensity of effort to perform a task, its causes may be related to different mechanisms within a work environment. To better understand the factors that directly influence the health of employees in the work environment, quantitative functional evaluation methods were used . Among the used methods, deserves spotlight the use of electromyography ( EMG ) surface and the examination of blood lactate level for the assessment of muscle fatigue . Another way to evaluate a fatigue was the analysis of workers psychophysiological characteristics, utilizing a questionnaire. Objective: The objective of this study was to analyze the physical and psychological stress on workers of deboning sector and observe whether the pause macro is sufficient to recover the worker. Material and Methods: Were evaluated eighteen male volunteers, aged 22 to 27 years, mean 24.4 ± 2.3 years, of the boning sector. The chosen muscle, for the analysis, was the extender cuff on the right upper limb. Data from electromyography, samples of blood lactate and bipolar fatigue questionnaire were collected during the normal routine of work of each participant at the beginning of the work week, on a Monday. Data were collected at three different points: the first collection was made at the beginning of the workday (A1), the second after three hours of work (A2) and the third was performed after 30 minutes of macro break of 90 minutes for lunch (A3). The interpretation of the questionnaire was based on a quantitative criterion, checking the numerical value of the difference between the beginning , middle and end of the working day for each item evaluated . For the examination of electromyography was analyzed the median frequency and for the lactate was analyzed the concentration levels between intervals. Results: All three tests showed the onset of labor fatigue. The electromyography showed a decrease in the median frequency from the first sample. There was a significant difference in the median frequency of EMG between each time interval, was also found a progressive increase in lactate levels. It was observed a significant increase in practically all variables in the questionnaire between periods of A1 and A2. Only the variables: nervousness, pain in thighs, leg pain and foot pain were not significantly different. The two variables that showed greater differences were fatigue (154.54%) and arm pain (178,57%). Conclusions: Meatpacking workers develop physical and psychological stress during activities. The macro break interval for rest was not enough for physical and psychological recovery during activities. These activities can lead to occupational diseases, since it is known that their etiological principles, the fatigue, acts as initial marker.