Distance running stride-to-stride variability for sagittal plane joint angles

Area of Science:

• Biomechanics
• Human Movement Science
• Sports Medicine

Background:

• Stride-to-stride variability (SSV) in distance running is linked to performance and injury risk.
• Prior research predominantly examined temporal and spatial stride characteristics.
• A gap exists in understanding SSV across different lower body joints and movement phases.

Purpose of the Study:

• To investigate differences in SSV among hip, knee, and ankle joints during stance and swing phases.
• To determine the correlation between SSV measures across different joints and phases.
• To identify which joints and phases contribute most to overall running stride variability.

Main Methods:

• Thirty recreational runners (39 ± 10 years) underwent motion capture (6 cameras, 200 Hz) during treadmill running.
• Kinematic data were analyzed for SSV in the sagittal plane for hip, knee, and ankle joints.
• A 2x3 repeated measures factorial ANOVA was employed to analyze differences in SSV.

Main Results:

• A significant interaction effect was found between joint and phase (p < 0.001).
• The knee joint during the swing phase demonstrated significantly higher SSV compared to all other conditions.
• Strong correlations (r = 0.80–0.88) were observed between stance and swing SSV for each joint.
• Moderate to strong correlations (r = 0.55–0.86) existed among the SSV of different joints.

Conclusions:

• The knee joint during the swing phase is a major contributor to overall stride-to-stride variability in runners.
• Despite joint-specific variations, runners exhibit consistent SSV patterns across multiple joints and movement phases.
• Understanding joint-specific SSV can provide insights into running mechanics, performance, and injury prevention strategies.