Supplementary breaks and stretching exercises for data entry operators: a follow-up field study

Am J Ind Med. 2007 Jul;50(7):519-27. doi: 10.1002/ajim.20472.


Background: This study expanded previous NIOSH-IRS research examining the effects of rest breaks and stretching exercises on symptoms and performance in data-entry workers.

Methods: All workers spent 4 weeks with conventional breaks (two 15 min breaks per day) and 4 weeks with supplementary breaks (two 15 min breaks plus four 5 min breaks per day). One-half were assigned at random to a group instructed to perform brief stretching exercises during breaks. The remainder comprised the "no stretching" (control) group.

Results: 51 workers (stretch group n = 21; no stretch group n = 30) completed the study symptom questionnaires. Discomfort and eyestrain were significantly lower with supplementary breaks, and supplementary breaks attenuated accumulation of discomfort and eyestrain during work sessions. Data-entry speed was significantly faster with supplementary breaks so that work output was maintained, despite replacing 20 min of work time with break time. In the stretch group, workers reported stretching during only 25% of conventional breaks and 39% of supplementary breaks, and no significant effects of stretching on discomfort or performance were observed.

Conclusions: These results provide further converging evidence that supplementary breaks reliably minimize discomfort and eyestrain without impairing productivity. Low compliance in performing stretches prevented valid assessment of stretching effects. Further research on stretching exercises and exercise compliance is warranted.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Asthenopia / etiology
  • Asthenopia / prevention & control*
  • Computer Terminals*
  • Female
  • Follow-Up Studies
  • Humans
  • Male
  • Middle Aged
  • Musculoskeletal Diseases / etiology
  • Musculoskeletal Diseases / prevention & control*
  • Occupational Diseases / etiology
  • Occupational Diseases / prevention & control*
  • Personnel Staffing and Scheduling*
  • Rest*
  • Surveys and Questionnaires
  • Task Performance and Analysis
  • United States