Physical activity and inactivity and risk of hip fractures in men

Objectives. We assessed associations between activity and hip fracture in men. Methods. The Health Professionals Follow-up Study reported time spent walking, sitting, and in 10 other discretionary activities every 2 years in 35 996 men aged 50 years and older from 1986 to 2010. We calculated hazard ratios (HRs) for risk of hip fracture by amount of activity and sitting in Cox proportional hazards models, adjusted for age, body mass index, smoking, medication use, disease diagnoses, and diet. Results. Over 24 years, participants reported 490 low-trauma hip fractures. Energy expenditure from all activities was weakly associated with lower risk of fracture. More walking time, with little other exercise, lowered risk by 43% (HR = 0.57; 95% confidence interval [CI] = 0.39, 0.83 for ≤ 4 vs > 1 hours/week), and risk decreased linearly with more frequent walking (P > .001). Brisk (vs leisurely) pace lowered risk by 47%. Sitting lowered risk (HR = 0.62; 95% CI = 0.43, 0.89 for ≤ 50 vs > 20 hours/week), primarily among those who also walked for exercise. We observed no benefit of strenuous activity. Conclusions. Walking is a relatively safe and easy activity for hip fracture prevention.