Evaluation of shoulder overload during acrobatic flight: Analysis of pilot’s self-report and surface electromyography (SEMG).

Background and Objectives: The physical injuries caused by +Gz include skeletal-muscle overloads. This study has aimed at demonstrating ergonomic conditions of the pilots from the Brazilian Air Force’s Aerial Demonstration Squadron (BAFADS) during flight.
Methods: All the 13 pilots from the BAFADS were evaluated through an interview. Surface electromyography (SEMG) was employed during the flight manoeuvre simulation (under normal and overload conditions).
Results: The report analyses showed perception of discomfort in the right shoulder related to +Gz. The SEMG showed moderate levels of shoulder muscles activation for normal contractions (± 25%). During vigorous contraction, levels of recruitment were high: upper trapezius fibres (± 105%), middle trapezius fibres (± 90%) and posterior deltoid fibres (± 95%). The great demand from the deltoid muscles (posterior fibres) infers a very high level of recruitment from the rotator cuff muscle, which may explain the discomfort in the pilots’ shoulder during the flight manoeuvre.
Conclusion: The mutual analysis of both methods not only does it demonstrate a correlation between symptoms and muscle recruitment, but also provides data to implement intervention measures for pilots’ physical training in order to minimise the discomfort symptoms during flights.