Manual handling of loads is the practice carried out by workers during putting, lifting, holding, moving, pushing or pulling a load. Mechanical handling of loads affect the health of workers and can cause musculoskeletal system disorders, e.g. low back pain because the extra strain is experienced by body muscles and bones and the natural resonant frequency of lumbar spine is disturbed which is normally 4-5 Hz. Manual handling is practised in all most all the working environment, i.e. factories, building sites, farms, offices and hospitals etc. Heavyweight lifting practice had adverse effects on the whole body, but the most affected region is the lumbar region (lower back) because it is the part exposed to pulling, torsion, muscular stretch and postural instability.
Risk Factors Involved in Lifting Heavy Load
- The risk of spine injury increases if the load is heavy. A weight of 20-25 is considered heavy for most of the people.
- Muscle fatigue occurs if weight is too large because posture instability occurs greatly to carry a large weight.
- If the load is slippery, it can cause mechanical injury.
- Twisting and bending of trunk cause extra stretching and pull of muscles, thus the risk of backache increase.
- Bent or awkward posture, e. bent trunk, raised arms or overstretched neck causes cervical spine injuries, loss of normal curvature of spine and neck pain and stiffness.
There are some risk factors which are associated with the load. For example:
- Weight and size of the load.
- The distance of load from the body.
- The distance which has to be covered with the load.
- The height of the load in comparison to the height of lifter.
- The frequency and number of weightlifting practice.
The risk factors associated with work environment are:
- Congested space
- Intense vibrations
- Excessive heat or cold
- Slippery and dirty floor.
- Excessive noise in surroundings
- Poor lighting
- Strong air movements in surroundings
Individual and lifestyle factors which have hazards for potential workers are:
- Age of worker
- Medical history
- Physical ability to bear the strain
- Lack of work experience and training.
According to a survey carried out by EU-27 in 2015, 33% of the workers among them who carry a heavy load, have complaints related to health issues. The group who has the highest exposure rates is of high-skilled manual workers. According to studies, back pain is the third most common cause of visiting the doctor all over the world; the first two are flue and fever.
The Role of Your Spine in Lifting Weight
Our spine is composed of vertebrae and discs among them. It has 3 natural curvatures, 2 concaves forward and 1 convex forward. The strength and resilience of our back are due to these curvatures and the shock absorbing effect of intervertebral discs. Due to this ability, a man can lift very heavy weight even more than his own body weight. But it is observed that in professional heavyweight lifting workers, the resilience of the spine is gradually lost because frequent postural changes occur during their routine work and normal curvatures of the spine are lost during this practice. Intervertebral discs may be injured, and nerves are pressed. This causes pain and numbness not only in the back but also in the other body parts supplied by these nerves. So, it is mandatory for heavy weight lifting workers to adopt precautionary measures in order to maintain their good health.
Safe Lifting Tips
Heavy lifters should adopt the following habits to maintain their best state of health during their work routine.
- Always stand near the weight.
- Contract the muscles of the abdomen.
- Always keep the spine straight so that its normal curvatures are not lost. Bend on knees.
- Grasp the load strongly.
- The most frequently recommended strategy for heavy load lifting workers is the use of lumbar belts (back support belt) which has a good effect on their overall body health. It is the best preventive measure for a backache.
The back support belt causes redistribution of spinal forces during lifting which has a very beneficial effect. According to study, lumbar support belts help in preventing lumbar strain and overall body fatigue. The belt grips up your lumbar region which helps you maintains normal posture or curvatures of the spine while you lift load. It also increases lumbosacral support, thus decreases the erector spinae myoelectric activity. This also reduces strain, extra stress and fatigue during a lift.
It has been observed that lumbar belt is used as primordial prevention by many heavy lifters and cargo workers. Please click here to take a look at Backrack™ Back Support Belt – A Unique, Patented Technology to Support Lower Back.