Effect of walking speed on inter-joint coordination differs between young and elderly adults

Area of Science:

• Biomechanics
• Neuroscience
• Gerontology

Background:

• Age-related changes in neuromuscular control significantly impact gait.
• Understanding inter-joint coordination across different walking speeds is crucial for assessing gait adaptability.
• Previous research has not fully elucidated age-specific strategies in gait adjustments.

Purpose of the Study:

• To investigate the effects of walking speed and age on inter-joint coordination patterns and variability.
• To compare how young and elderly adults adjust their gait coordination at preferred, faster, and slower speeds.
• To identify age-related differences in neuromuscular control strategies during gait modifications.

Main Methods:

• Gait analysis was performed on 10 young and 10 elderly adults at three self-selected walking speeds.
• Continuous relative phase (CRP) was calculated to assess inter-joint coordination between adjacent joints.
• Cross-correlation and root-mean-square (RMS) differences evaluated coordination pattern changes; deviation phase (DP) measured coordination variability.

Main Results:

• Young adults showed greater RMS differences in hip-knee CRP between slower and preferred speeds compared to faster speeds; elderly adults did not exhibit this difference.
• Significant group differences in RMS and cross-correlation were found for hip-knee CRP between slower and preferred speeds.
• No significant effects of walking speed or age were observed for knee-ankle CRP; hip-knee DP showed speed effects but no group differences.

Conclusions:

• Young and elderly adults employ different neuromuscular control strategies to adapt to changes in walking speed.
• Elderly adults may have a less adaptable hip-knee coordination pattern when altering walking speed compared to young adults.
• These findings highlight age-specific mechanisms in the neuromuscular control of gait adjustments.