Force Exertion

Force is the amount of muscular effort expended to perform work. Exerting large amounts of force can result in fatigue and contribute to injury. The amount of force exerted depends on a combination of factors, including:

• The effort with which one strikes an object (e.g. pounding the keyboard).
• The shape and dimensions of an object you are working with.
• How you grip an object or tool.
• The preciseness of motion required doing the task.
• Duration of force applied by the muscles (e.g., the amount of time spent without a muscle-relaxation break).
• Awkward postures (over-reaching).

Manual material handling tasks such as pushing, pulling and lifting typically require forceful exertion. Such exertion may result in back pain or other musculoskeletal disorders. However, other tasks such as using hand tools and operating equipment can also require forceful exertions on a particular muscle or group of muscles. Ways to reduce forceful exertions include:

• Use mechanical assistance to move heavy loads when possible;
• Use power tools to avoid high forces;
• Reduce the weight of loads that need to be handled manually;
• Reduce the resistance that the worker must act against when pushing/pulling.