Association of intensity-based walking steps and incident falls: a population-based cohort study

Background: Falls are the leading cause of morbidity and mortality, yet they are largely preventable. While walking has well-established health benefits, its role in falls remains unclear. We aimed to examine the association between walking and fall risk. Methods: Walking steps were defined as purposeful walking steps (≥40 steps/min) and incidental walking steps (<40 steps/min), differentiated by walking intensity. We estimated hazard ratios (HRs) for incident falls using Cox proportional hazards models across the four walking step categories. Risk ratios (RRs) for the number of falls were estimated using Poisson regression. We also estimated the association between walking steps and the risk of incident hip fracture as the secondary outcome. Results: We included 94,422 participants aged 42-78 years from the UK Biobank, with a median follow-up of 6.87 years. We adjusted multivariable models for demographic, lifestyle, and clinical covariates. Compared with the lowest purposeful waking group (≤3999 steps/day), the second (HR = 0.75; 95% confidence interval (CI) = 0.60, 0.92), third (HR = 0.65; 95% CI = 0.52, 0.82), and fourth (HR = 0.68; 95% CI = 0.54, 0.86) group had lower risks of incident falls. Also, the RRs for the second (RR = 0.78; 95% CI = 0.68, 0.90), third (RR = 0.74; 95% CI = 0.64, 0.85), and fourth (RR = 0.72; 95% CI = 0.62, 0.84) group showed similar results. We also observed an inverse association between purposeful walking steps and hip fracture risk, while incidental walking steps showed no significant association. Conclusions: Higher purposeful walking steps were associated with a lower risk of incident falls, number of falls, and incident hip fracture, although residual confounding cannot be ruled out in this observational study. These findings may help inform future step-based recommendations for fall prevention.