The Mediating Influence of Physical Activity on Work Ability among Nurses Suffering from Low Back Pain: A Multidimensional Study of Pain Intensity and Quality of Life

Background: Low back pain (LBP) represents a substantial occupational burden for nursing professionals, frequently precipitating diminished work ability and premature professional attrition. Although the clinical manifestations of LBP are well-documented, the collective influence of physical activity (PA), pain intensity (PI), and health-related quality of life (HRQoL) on the functional capacity of nurses in Sub-Saharan Africa remains insufficiently characterized. This study investigated the predictive utility of these multidimensional variables regarding the work ability of nurses with mechanical LBP in North-Eastern Nigeria. Methods: A cross-sectional investigation was conducted among 188 nursing professionals at the Federal Teaching Hospital, Gombe, Nigeria. Participants were recruited via consecutive sampling. Standardized instrumentation included the International Physical Activity Questionnaire (IPAQ), the Numeric Pain Rating Scale (NPRS), the RAND-36 Health Survey, and the Work Ability Index (WAI). Multiple linear regression analysis was utilized to determine the extent to which PA, PI, and HRQoL predicted work ability. The level of statistical significance was established at $ < 0.05. Results: The study cohort exhibited a mean age of 34.6 -8.7 years, with a predominant female representation (60.1%). The regression model demonstrated statistical significance, F(3, 184) = 12.525, p = .001, accounting for 21.5% of the variance in work ability scores (R ² = .215). Among the evaluated predictors, physical activity emerged as the most robust positive contributor ($\beta = .435, p = .002). While HRQoL manifested a significant positive correlation (r = .388) and pain intensity a significant negative correlation (r = -.312) with work ability, physical activity remained the primary determinant of functional capacity within the combined model. Conclusions: Physical activity is a paramount predictor of work ability among nurses with LBP, exerting a greater influence on professional functionality than subjective pain intensity. These findings advocate for a strategic shift in occupational health policy from reactive symptom management toward proactive functional preservation. Institutionalizing workplace-based exercise interventions and ergonomic support is recommended to bolster the professional longevity and productivity of the nursing workforce in resource-constrained environments.