title: Physical workload, trapezius muscle activity, and neck pain in nurses' night and day shifts: a physiological evaluation.
abstract: The purpose of this study was to compare physical workload, electromyography (EMG) of the trapezius muscle, neck pain and mental well-being at work between night and day shifts in twenty Swiss nurses. Work pulse (average increase of heart rate over resting heart rate) was lower during night (27 bpm) compared to day shifts (34 bpm; p < 0.01). Relative arm acceleration also indicated less physical activity during night (82% of average) compared to day shifts (110%; p < 0.01). Rest periods were significantly longer during night shifts. Trapezius muscle rest time was longer during night (13% of shift duration) than day shifts (7%; p < 0.01) and the 50th percentile of EMG activity was smaller (p = 0.02), indicating more opportunities for muscle relaxation during night shifts. Neck pain and mental well-being at work were similar between shifts. Subjective perception of burden was similar between shifts despite less physical burden at night, suggesting there are other contributing factors.
authors.affiliation: Department of Health Sciences and Technology, ETH Zurich, Sensory-Motor Systems Lab, 8092 Zurich, Switzerland; Exercise Physiology Lab, Institute of Human Movement Sciences and Sport, ETH Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland. Electronic address: corinne.nicoletti@hest.ethz.ch.
authors.forename: Corinne
authors.initials: C
authors.lastname: Nicoletti
authors.affiliation: Exercise Physiology Lab, Institute of Human Movement Sciences and Sport, ETH Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland; Zurich Center for Integrative Human Physiology (ZIHP), University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland. Electronic address: christina.spengler@hest.ethz.ch.
authors.forename: Christina M
authors.initials: CM
authors.lastname: Spengler
authors.affiliation: Department of Health Sciences and Technology, ETH Zurich, Sensory-Motor Systems Lab, 8092 Zurich, Switzerland; Holistics Prosthetics Research Center, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku 606-8585, Japan. Electronic address: tlaeubli@ethz.ch.
authors.forename: Thomas
authors.initials: T
authors.lastname: Läubli
mesh_terms: D000328:Adult; D004576:Electromyography; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D009043:Motor Activity / Q000502:physiology; D019547:Neck Pain / Q000209:etiology*; D009726:Nurses / Q000706:statistics & numerical data*; D009784:Occupational Diseases / Q000209:etiology*; D013312:Stress, Physiological / Q000502:physiology; D064171:Superficial Back Muscles / Q000502:physiology*; D014940:Work Schedule Tolerance / Q000502:physiology; D016526:Workload
keywords: Electromyography; Shift work; Stress