Occupation, participation, inclusion, work role postural control in different load handling tasks.

Area of Science:

• Biomechanics
• Ergonomics
• Human Factors Engineering

Background:

• Manual material handling is a primary cause of musculoskeletal injuries.
• Worker postural stability is affected by load handling methods, duration, and weight.
• Key factors include balance, center of pressure, and electromyography.

Purpose of the Study:

• To assess postural balance in female volunteers performing manual material handling tasks.
• To compare five common load handling techniques.
• To identify how different load positions influence postural control.

Main Methods:

• Ten female subjects performed manual material handling tasks with a 9 kg load.
• Five lifting methods were tested: upfront, on head, sideways (left/right), and at the back.
• Postural control was measured using normalized electromyography (EMG) of back and leg muscles and center of pressure (COP) displacements.

Main Results:

• Increased medio-lateral and anterio-posterior COP displacements were observed when lifting loads directionally.
• Elevated activity in back muscles was reported with directional lifting.
• Load position significantly influenced COP displacements and muscle activity.

Conclusions:

• The position of the load has a significant impact on postural stability during manual material handling.
• Understanding these effects is crucial for designing safer manual handling tasks and preventing injuries.