Event standardization of sit-to-stand movements.

Area of Science:

• Biomechanics
• Human Movement Analysis
• Kinesiology

Background:

• Standardized methods for analyzing sit-to-stand (STS) movements are lacking, unlike gait analysis.
• Previous STS studies often used varied methods and restricted natural movement.
• A simple method for observing natural STS movements is needed.

Purpose of the Study:

• To compare commonly performed STS movements.
• To propose a standard system for defining identifiable sequential events in STS.
• To establish a reliable method for assessing STS functionality.

Main Methods:

• Recorded ground reaction forces of 100 healthy adults (50 male, 50 female).
• Participants performed STS from a standard chair under four arm-use conditions: arms free, hands on knees, using armrests, and arms crossed.
• Identified 11 sequential events from vertical, fore-aft, and lateral force dimensions.

Main Results:

• Eleven distinct movement events were identified across all arm-use conditions for every participant.
• Using armrests resulted in significantly less average force during seat-off and peak force events compared to other conditions.
• The armrests condition showed a significantly longer time to reach vertical peak force.

Conclusions:

• The identified sequential events occurred consistently across all individuals and arm-use conditions.
• This simple, standardized method can assess and compare patient functionality in STS movements.
• The findings facilitate comparisons across different STS research studies and clinical assessments.