Effects of muscular endurance training on musculoskeletal disorders in teachers

Resumo

Introduction: Physical exercise is indicated to reduce the incidence of musculoskeletal symptoms in teachers. Objective: To evaluate the effects of muscular endurance training on muscle strength and musculoskeletal symptoms related to the lower limbs of public elementary school teachers. Materials and methods: Thirtyone female teachers were divided into two groups: control (CG, n = 15) and muscular endurance training (TG, n = 16). The training consisted of two sets of 15 repetitions of exercises for quadriceps and hamstring muscle groups, twice a week, for 7 weeks, which were conducted with 50% of 10 repetition maximum(10RM) (first to fourth week) and 60% of 10 RM (fifth to seventh week). Musculoskeletal symptoms (Nordic Musculoskeletal Questionnaire), isometric peak torque (Load cell) and muscle strength (10RM) were assessed before and after intervention. ANOVA for repeated measures and Tukey post hoc were used to analyse strength and peak torque of quadriceps and hamstrings and Chi-square goodness-of-fit test were used to analyse the frequency of occurrence of osteomuscular symptoms. Results: The highest incidence of symptoms was found in the lumbar region in both groups. Training caused increased muscle strength of the quadriceps and hamstrings, but there were no significant differences in either the peak torque in the quadriceps and hamstrings or in the reduction of musculoskeletal symptoms. Conclusion: The exercise program performed in this study increased the dynamic strength in the TG in relation to the CG, but did not alter the incidence of symptoms in the lumbar region and lower limbs in neither of the groups. Thus, results suggest that the duration of intervention may not have been enough to increase peak torque and decrease musculoskeletal symptoms.