Abstract
Although work-related musculoskeletal disorders (MSDs) are now well recognized and documented, tests to diagnose and quantify these disorders are not well developed. Late presentation of MSDs is believed to equate to poor outcomes, and lack of reliable monitoring of treatment may lead to an inappropriate return to work. The authors report on a study to quantify “normal” muscle activity in volunteers. Subjects were randomly divided into control and intervention (exercise) groups. Using sonography, the authors measured the diameters of the selected soft tissue twice daily over a period of a week, with an extra measurement after exercise in the intervention group. Results indicated that there was no statistically significant difference between the intervention and control groups over any of the time frames or in dominant and nondominant sides. However, results indicated there was a day-to-day and diurnal difference in muscle size, indicating that muscles do not remain static in size.