Group-based exercise at workplace: short-term effects of neck and shoulder resistance training in video display unit workers with work-related chronic neck pain-a pilot randomized trial.

Effectiveness of exercise therapy in video display unit (VDU) workers with work-related chronic neck pain (W-RCNP) is unclear. The aim of the study was to assess the efficacy of group-based neck-shoulder resistance exercises on symptoms and muscular function in VDU workers with W-RCNP. Thirty-five employees with CNP were randomly assigned to neck-shoulder resistance exercise (NSRE) group or to conventional stretching and postural exercise (SPE) group. Participants trained 45 min, twice a week for 7 weeks. Primary outcomes were pain intensity (0-10 numeric rating scale, NRS) and pain-related disability (Vernon Neck Disability Index, NDI). Secondary outcomes were cervical active range of motion (AROM), endurance of neck flexors, strength of shoulder abductors, and health-related quality of life (SF-36). Post-treatment, pain and disability decreased 2.5 and 5 points in NSRE (p = 0.001) and 5 and 8 points in SPE (p = 0.002), with no significant differences between groups. AROM improved significantly in both groups; between-group differences were not significant. Neck flexors endurance and shoulder abductors strength improved by 59.6 and 34.2% (p = 0.001) in the NSRE group and by 27.6% (p = 0.009) and 2.3% (p = 0.002) in the SPE group; between-group differences were significant (p = 0.016 and p < 0.001, respectively). SF-36 score remained unchanged. NSRE and SPE are feasible and equally effective in reducing pain and pain-related disability as group exercises in W-RCNP. NSRE may provide some advantage in improving strength and endurance in neck muscles. Further, larger studies should confirm these findings and assess whether a better muscle function confers long-term clinical advantages.