Pushing and pulling, technique and load effects: an electromyographical study

Area of Science:

• Biomechanics
• Occupational Health
• Ergonomics

Background:

• Manual handling, including lifting, poses significant physical risks.
• Redesigned tasks often incorporate manual handling devices, increasing pushing and pulling.
• Limited research exists on muscle activity during pushing and pulling tasks.

Purpose of the Study:

• To investigate muscle activation responses during pushing and pulling.
• To enhance understanding of injury risk associated with these activities.
• To inform the development of effective ergonomics intervention strategies.

Main Methods:

• A laboratory study assessed muscle activation in nine upper and lower body muscles.
• Three distinct push/pull techniques and two load levels (250 kg and 500 kg) were evaluated.
• Unloaded walking served as a control for lower limb muscle activation analysis.

Main Results:

• Shoulder and upper extremity muscles showed greater responses to technique and load variations compared to lower limb muscles.
• High levels of erector spinae activation were consistently observed across all experimental conditions.
• Each push/pull technique resulted in a unique muscle activation pattern.

Conclusions:

• Alternating between different push/pull techniques may help mitigate early-onset muscle fatigue.
• Further research into muscle activation during pushing and pulling is crucial for injury prevention.
• Understanding these biomechanical responses can guide safer manual handling practices.