Effects of Surface Inclinations and Carrying Aid Types on Postural Stability During Posterior Load Carriage in Rural...

Area of Science:

• Biomechanics
• Ergonomics
• Human Factors Engineering

Background:

• Posterior load carriage (PLC) on inclined surfaces poses significant challenges to postural stability.
• Traditional carrying aids like fabric shawls are common, but their biomechanical effects are not fully understood.

Purpose of the Study:

• To investigate the impact of surface inclinations and carrying aids on postural stability and lower extremity posture during PLC.
• To compare the biomechanical effects of a fabric shawl versus a frame backpack during inclined PLC tasks.

Main Methods:

• Twelve participants performed static PLC tasks on three surface inclinations (-25º, 0º, 25º) using a fabric shawl and a frame backpack.
• Measurements included center of pressure (COP), joint angles, and subjective ratings of steadiness and discomfort.
• Data were analyzed using repeated measures ANOVA.

Main Results:

• Uphill PLC significantly reduced postural stability and increased postural deviations.
• Frame backpacks enhanced stability on inclines but led to greater ankle and knee joint deviations.
• Fabric shawls minimized postural deviations but were less effective in maintaining stability on uphill inclines.

Conclusions:

• Frame backpacks can improve stability during inclined PLC but may increase joint strain, indicating a need for ergonomic design optimization.
• The choice of carrying aid impacts postural stability and lower extremity biomechanics differently depending on the surface inclination.