An Investigation of Torso Muscle Fatigue and Its Relation to Discomfort during Vertical Vibration Exposure

Author

Nathan H. Hodges

Date of Award

3-2024

Document Type

Thesis

Degree Name

Master of Science in Systems Engineering

Department

Department of Systems Engineering and Management

First Advisor

Michael E. Miller, PhD

Abstract

Military and civilian helicopter pilots often experience back pain attributed to vibration exposure during flight and sustained poor posture, known as the "helicopter hunch." This study investigated torso muscle activation using surface electromyography (EMG) to assess the relationship between discomfort and muscle fatigue. Eight subjects were exposed to different vibration frequencies over two-hour periods, with EMG data collected every five minutes. Significant differences in muscle activation were observed before and after vibration exposure, suggesting increased muscle activation during vibration compared to prolonged seating alone. Discomfort surveys indicated higher discomfort during vibration.

AFIT Designator

AFIT-ENV-MS-24-M-127

Comments

A 12-month embargo was observed for posting this work on AFIT Scholar.

Distribution Statement A, Approved for Public Release. PA case number on file.

Recommended Citation

Hodges, Nathan H., "An Investigation of Torso Muscle Fatigue and Its Relation to Discomfort during Vertical Vibration Exposure" (2024). Theses and Dissertations. 7795.
https://scholar.afit.edu/etd/7795