Impact of Anterior Load Carriage on Dynamic Sagittal Spinal Alignment: A Comparative Study Between Individuals Below and Above 65 Years.

OBJECTIVES: To examine the effects of anterior load carriage on dynamic sagittal spinal alignment during the gait cycle in younger (<65 y) and older (≥65 y) adults. DESIGN: Cross-sectional study of 47 participants aged 20-80 years categorized as young and older adults. Participants walked at self-selected speeds with and without a 4.5 kg anterior chest load. Whole-body kinematics were recorded using a 19-camera infrared motion capture system. Outcome measures included lumbar lordosis (LL), thoracic kyphosis (TK), trunk inclination (TI), sagittal trunk shift (STS), and pelvic tilt (PT). Gait-cycle-dependent differences were analyzed using statistical parametric mapping. RESULTS: The mean age was 41 years in young adults (n=28) and 70 years in older adults (n=19). Anterior load carriage increased LL during portions of the gait cycle and reduced TI throughout the entire gait cycle. Younger adults demonstrated greater LL and lower TI than older adults. A significant age-by-load interaction for TI was observed during portions of the gait cycle. CONCLUSIONS: Anterior load carriage alters spinal alignment by increasing LL and reducing TI during walking, with distinct age-related patterns. These results provide valuable reference data and a foundation for future studies on load management and ergonomic interventions across the adult lifespan.