Changes in postural stability induced by a ball-and-board game designed from a systems perspective

Area of Science:

• Biomechanics
• Systems Neuroscience
• Rehabilitation Science

Background:

• Postural behavior emerges from complex agent-environment interactions, with variability enabling adaptive balance solutions.
• Lower limb rehabilitation should adopt a systems perspective for assessment and intervention.
• A novel ball-and-board game was designed to foster lower limb and inter-agent interactions.

Purpose of the Study:

• To investigate the impact of a systems-designed ball-and-board game on postural stability.
• To assess changes in postural stability using variability measures derived from a systems perspective.

Main Methods:

• Twenty-four novice participants formed twelve dyads, playing a joint-action ball-and-board game on an unstable surface (BOSU).
• Three-dimensional body and ball movements were captured using an 8-camera motion system.
• Postural stability was evaluated using linear and nonlinear variability measures of center of mass kinematics.

Main Results:

• Practice led to significant postural changes, notably in the anteroposterior plane, with decreased standard deviation and increased sample entropy of oscillations.
• Higher-performing participants exhibited greater complexity (sample entropy) in postural oscillations, enhancing their ability to resist perturbations.
• Postural pathways were heterogeneous, suggesting diverse adaptive strategies.

Conclusions:

• The game induced heterogeneous evolution of postural oscillation variability, indicating broad exploration of postural solutions and enhanced adaptability.
• Increased adaptability to balance perturbations was particularly evident in high-performing individuals with more complex postural variability.
• The game promoted postural reorganization, suggesting its potential for clinical application in rehabilitation settings.