Effects of workplace upper extremity resistance exercises on function and symptoms of workers at a tertiary hospital: a randomized controlled trial protocol.

Background: Work-related musculoskeletal disorders (WRMDs) are often caused by inadequate use of the musculoskeletal system during work. Evidence suggests that multimodal intervention through exercises, massage, education, and ergonomic guidelines reduces pain and symptoms in the neck and upper extremities and help to prevent musculoskeletal disorders. The purpose of this study will be to assess the additive effectiveness of a specific and individualized workplace strengthening exercise program to an ergonomic guidance in reducing fatigue, pain and discomfort in the upper extremities and neck perceived by workers.

Methods: This trial was designed according to the Consolidated Standards of Reporting Trials - CONSORT guidelines. Participants will be employees of a tertiary hospital, with any complaints of pain or discomfort in the upper extremities during the past 12 months, without clinical musculoskeletal diagnosis. 166 participants will be randomized into parallels groups as control and workplace exercises. The primary outcomes will be Numerical Pain Scale, isokinetic muscle strength of abduction and isometric handgrip strength. Secondary outcomes on discomfort, fatigue, work capacity and dysfunction will be assessed by QuickDASH, Patient Specific Functional Scale, Neck Disability Index, Need for recovery, Work Ability Index self-report questionnaires and FIT-HANSA performance test. The Ergonomic Work Analysis will be done by Quick Expose Check, RULA, REBA, RARME, ROSA and HARM risk assessment ergonomic tools. We will analyze the difference between baseline and 12 weeks of intervention by T test of independent samples (95% confidence interval, p < 0.05). Clinical significance will be analyzed by the minimum clinically important difference and effect size by Cohen index. The association between the variables will be analyzed by construct validity with the hypothesis of correlations between pain and muscle strength, strength and functionality and strength and fatigue.

Discussion: Although studies have shown promise outcomes for workplace exercises as an available therapeutic resource used to minimize complaints of pain and discomfort related to work, the results of this study aim to bring evidence about the benefit of a specific resistance exercise as an effective modality to facilitate mechanisms of neuromuscular adaptations, with gradual and posterior hypertrophy in the later phases.

Trial Registration: (NCT04047056, https://clinicaltrials.gov/ct2/show/NCT04047056?term=NCT04047056&draw=2&rank=1 ) on Dec 03, 2020.