Electromyographic analysis of postural overload caused by bulletproof vests on public security professionals

Abstract

Introduction: Military police activity individuals performing operational activity remain 12 hours using mandatory safety equipment. This work aimed to verify the electromyographic response in operational military police officers before and after a cycle of two working days. Methods: Forty-four male individuals were evaluated, with an average age of 34.59 ± 8.05. The used protocol consisted in the evaluation of paravertebral muscles and rectus abdominis muscles in a maximum isometric voluntary contraction test (MVC) during trunk extension movements, starting from the sitting position. Moreover, the Roland-Morris functional evaluation questionnaire and the Corlett and Manenica diagram for painful areas were used. An electromyograph with 16 pre-set channels was used. Signals were processed in time (EMG ME ) and spectral (EMG MF ) domains, using the MatLab  program. The Shapiro-Wilk test and Wilcoxon Signed Ranks Test were applied. Statistical analyses were performed through the SPSS v21.0 software and Microsoft Office Excel 2010, considering p < 0.05 as significance level. Results: Results showed statistical differences in the post-working day for time analysis, an EMG ME decrease in the right rectus abdominis muscle (p = 0.016) and in the age-stratified sample, with individuals over 31 years old (p = 0.016); in the spectral analysis, EMG MF reduction in the right iliocostalis (p = 0.027) and right and left side in the stratified sample, in individuals over 31 years old and with more than 10 years of service. Conclusion: The used protocol highlighted a decrease in the amplitude of the electromyographic signal, as well as possible muscle fatigue on the right side where officers usually carry their weapons.

Importance of Ability-Based Training for Law Enforcement Recruits

“…Abdominal muscular endurance and lumbo-pelvic stability are also an important consideration for law enforcement recruits, and were included in the example program (Table 4). This is especially important considering the load carriage demands that recruits will encounter when they graduate academy and become officers (16). As sit-ups are a staple within law enforcement fitness testing (7,9,10,12,15,35,37,39,46,59), they are often performed during academy.…”