title: Effect of Workplace- versus Home-Based Physical Exercise on Muscle Response to Sudden Trunk Perturbation among Healthcare Workers: A Cluster Randomized Controlled Trial.
abstract: OBJECTIVE
  The present study investigates the effect of workplace- versus home-based physical exercise on muscle reflex response to sudden trunk perturbation among healthcare workers.
  
  
  METHODS
  Two hundred female healthcare workers (age: 42 [SD 11], BMI: 24 [SD 4], and pain intensity: 3.1 [SD 2.2] on a scale of 0-10) from 18 departments at three hospitals were randomized at the cluster level to 10 weeks of (1) workplace physical exercise (WORK) performed in groups during working hours for 5 × 10 minutes per week and up to 5 group-based coaching sessions on motivation for regular physical exercise, or (2) home-based physical exercise (HOME) performed during leisure time for 5 × 10 minutes per week. Mechanical and neuromuscular (EMG) response to randomly assigned unloading and loading trunk perturbations and questions of fear avoidance were assessed at baseline and 10-week follow-up.
  
  
  RESULTS
  No group by time interaction for the mechanical trunk response and EMG latency time was seen following the ten weeks (P = 0.17-0.75). However, both groups demonstrated within-group changes (P < 0.05) in stopping time during the loading and unloading perturbation and in stopping distance during the loading perturbation. Furthermore, EMG preactivation of the erector spinae and fear avoidance were reduced more following WORK than HOME (95% CI -2.7--0.7 (P < 0.05) and -0.14 (-0.30 to 0.02) (P = 0.09)), respectively. WORK and HOME performed 2.2 (SD: 1.1) and 1.0 (SD: 1.2) training sessions per week, respectively.
  
  
  CONCLUSIONS
  Although training adherence was higher following WORK compared to HOME this additional training volume did not lead to significant between-group differences in the responses to sudden trunk perturbations. However, WORK led to reduced fear avoidance and reduced muscle preactivity prior to the perturbation onset, compared with HOME. This trial is registered with Clinicaltrials.gov (NCT01921764).
authors.affiliation: National Research Centre for the Working Environment, Lersø Parkallé 105, 2100 Copenhagen, Denmark ; Department of Sports Science and Clinical Biomechanics, SDU Muscle Research Cluster (SMRC), University of Southern Denmark, Campusvej 55, 5230 Odense, Denmark.
authors.forename: Markus D
authors.initials: MD
authors.lastname: Jakobsen
authors.affiliation: National Research Centre for the Working Environment, Lersø Parkallé 105, 2100 Copenhagen, Denmark ; Department of Sports Science and Clinical Biomechanics, SDU Muscle Research Cluster (SMRC), University of Southern Denmark, Campusvej 55, 5230 Odense, Denmark.
authors.forename: Emil
authors.initials: E
authors.lastname: Sundstrup
authors.affiliation: National Research Centre for the Working Environment, Lersø Parkallé 105, 2100 Copenhagen, Denmark ; Physical Activity and Human Performance Group, SMI, Department of Health Science and Technology, Aalborg University, Fredrik Bajers Vej 7, 9220 Aalborg, Denmark.
authors.forename: Mikkel
authors.initials: M
authors.lastname: Brandt
authors.affiliation: National Research Centre for the Working Environment, Lersø Parkallé 105, 2100 Copenhagen, Denmark ; Department of Sports Science and Clinical Biomechanics, SDU Muscle Research Cluster (SMRC), University of Southern Denmark, Campusvej 55, 5230 Odense, Denmark ; Electronics and Computer Science, Faculty of Physical and Applied Sciences, University of Southampton, University Road, Southampton SO17 1BJ, UK.
authors.forename: Kenneth
authors.initials: K
authors.lastname: Jay
authors.affiliation: Department of Sports Science and Clinical Biomechanics, SDU Muscle Research Cluster (SMRC), University of Southern Denmark, Campusvej 55, 5230 Odense, Denmark.
authors.forename: Per
authors.initials: P
authors.lastname: Aagaard
authors.affiliation: National Research Centre for the Working Environment, Lersø Parkallé 105, 2100 Copenhagen, Denmark ; Physical Activity and Human Performance Group, SMI, Department of Health Science and Technology, Aalborg University, Fredrik Bajers Vej 7, 9220 Aalborg, Denmark.
authors.forename: Lars L
authors.initials: LL
authors.lastname: Andersen
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D003718:Denmark; D004576:Electromyography; D015444:Exercise / Q000502:physiology*; D005081:Exercise Therapy / Q000379:methods*; D005260:Female; D006282:Health Personnel; D006801:Humans; D008297:Male; D008875:Middle Aged; D009132:Muscles / Q000502:physiology*; D059408:Pain Management; D017132:Workplace