Evaluating plantar biomechanics while descending a single step with different heights

Area of Science:

• Biomechanics
• Human Movement Analysis
• Sports Medicine

Background:

• Understanding the biomechanics of stair descent is crucial for injury prevention.
• Transition steps present unique challenges compared to level walking or standard stair negotiation.
• Limited research exists on the specific plantar pressure adaptations during single transition step descents from varying heights.

Purpose of the Study:

• To investigate the plantar biomechanics of healthy young males during single transition step descents.
• To analyze the effects of varying step heights (5, 15, 25, 35 cm) on plantar pressure distribution and foot landing strategies.
• To examine the influence of dominant versus non-dominant foot leading on biomechanical parameters.

Main Methods:

• Thirty healthy young males participated in the study.
• Plantar pressure data were collected using the F-scan insole system.
• Participants performed single transition step descents from four different step heights, leading with either their dominant or non-dominant foot.

Main Results:

• Landing strategy shifted from rearfoot to forefoot contact as step height increased from 15 cm to 25 cm.
• Center of plantar pressure (COP) parameters for the leading foot were significantly larger and increased with step height.
• Vertical ground reaction forces decreased with increasing step height, with altered load distribution between leading/trailing and dominant/non-dominant feet.

Conclusions:

• Altered foot landing strategies, changing COP, and uneven force distribution during step descent compromise biomechanical stability.
• These changes challenge the ability to control motion and respond adaptively, increasing the risk of dynamic balance loss.
• This heightened risk is associated with an increased likelihood of ankle sprains and falls.