Effect of different types of rest-break interventions on neck and shoulder muscle activity, perceived discomfort and productivity in symptomatic VDU operators: a randomized controlled trial

Int J Occup Saf Ergon. 2014;20(2):339-53. doi: 10.1080/10803548.2014.11077048.


Objective: This study evaluated the effect of different types of activities during rest-break interventions on neck and shoulder muscle activity, muscle discomfort and productivity among symptomatic video display unit (VDU) operators performing prolonged computer terminal work.

Study design and setting: Randomized controlled trial was used. Thirty symptomatic VDU operators were randomly assigned to 2 active break groups (stretching and dynamic movement) and a reference group. The subjects performed the same typing task for 60 min and received 3-min breaks after each 20 min of work. Root mean square and median frequency were calculated for neck and shoulder muscle activity. Muscle discomfort was measured with Borg's CR-10 scale. Productivity was measured by counting words.

Results: There were no significant differences between the types of activities during breaks on neck and shoulder muscle activity, muscle discomfort or productivity. However, there was a significant difference in the level of muscle discomfort over time.

Conclusions: Three types of activity during breaks showed a favourable effect on neck and shoulder muscle activity and productivity, and a positive effect on muscle discomfort in symptomatic VDU operators.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Computer Terminals*
  • Electromyography
  • Female
  • Humans
  • Muscle, Skeletal / physiology*
  • Musculoskeletal Pain / epidemiology*
  • Musculoskeletal Pain / prevention & control
  • Neck Muscles / physiology
  • Neck Pain / epidemiology
  • Neck Pain / prevention & control
  • Occupational Diseases / epidemiology
  • Occupational Diseases / prevention & control
  • Occupational Health*
  • Rest*
  • Shoulder Pain / epidemiology
  • Shoulder Pain / prevention & control
  • Superficial Back Muscles / physiology
  • Task Performance and Analysis*
  • Workload
  • Young Adult