Stabilisation times after transitions to standing from different working postures.

Area of Science:

• Occupational Health
• Biomechanics
• Ergonomics

Background:

• Maintaining non-erect working postures is common in many job tasks.
• Transitioning to a standing position from these postures can lead to instability and increase fall risk.

Purpose of the Study:

• To quantify the degree of postural imbalance during transitions to standing.
• To evaluate the impact of different working postures and their durations on stabilisation time.

Main Methods:

• Forty-five male participants adopted four working postures (bent at waist, squat, forward kneel, reclined kneel) for three durations.
• Participants transitioned to quiet standing at a self-selected pace.
• Stabilisation time, measured by centre of pressure velocity, was used as the primary metric.

Main Results:

• Working posture significantly affected stabilisation time, but duration within posture did not.
• Transitions from a bent-at-waist posture exhibited the longest stabilisation times.
• Kneeling postures resulted in the shortest stabilisation times, indicating quicker stabilisation.

Conclusions:

• Working posture is a critical factor influencing postural control during transitions to standing.
• Findings suggest potential for task redesign in high-risk occupations like construction to mitigate imbalance and falls.
• Kneeling postures may offer better short-term stability upon standing compared to bent-at-waist or squatting postures.