Footstrike angle cut-off values to classify footstrike pattern in runners

Area of Science:

• Biomechanics
• Sports Science
• Running Mechanics

Background:

• Footstrike angle (FSA) is commonly used to classify footstrike patterns (FSP).
• Previous studies lack consistent FSA cut-off values for accurate FSP classification.
• Validated cut-off values are needed to standardize FSP analysis in runners.

Purpose of the Study:

• To validate footstrike angle (FSA) cut-off values for classifying footstrike patterns (FSP) in runners.
• To establish reliable criteria for differentiating between rearfoot, midfoot, and forefoot striking patterns.
• To provide standardized parameters for running gait analysis.

Main Methods:

• Participants included experienced runners, novice runners, and untrained individuals.
• Running data (FSA and Stride Index) were collected on an instrumented treadmill at preferred speeds.
• Receiver Operating Characteristic (ROC) curve analysis with Youden index determined optimal FSA cut-off values.

Main Results:

• Optimal FSA cut-off values were established: -0.8° for forefoot strike and -7.4° for rearfoot strike.
• Minor variations in cut-off values were observed across different running experience levels.
• A wider cut-off range for midfoot strikers was noted with a modified strike index.

Conclusions:

• This study successfully validated and established precise footstrike angle (FSA) cut-off values for runners' footstrike pattern (FSP) classification.
• The findings provide a standardized method for analyzing running gait and categorizing FSP.
• These validated cut-offs can enhance the consistency and accuracy of research and clinical assessments in running biomechanics.