Back muscle strength

Test 4 tests upper back muscle strength (Fig. 9-4) ... 

People vary in size, weight, strength, and physical condition. Physical condition includes general physical fitness, strength and conditioning of muscles, condition of joints, and other factors. Back muscles reacting to a lifted load compress the vertebrae of the spine. The intervertebral tissues have limits. Some studies have estimated the compressive load limits of spinal elements, but the capacity for an individual and particular spinal locations will vary. It is difficult to predict where and under what conditions an individual will experience pain, strain a muscle or experience some other form of injury. 

Where loads have to be lifted this can most effectively be carried out when standing provided that the correct lifting techniques are used (section 3.8.4). However, it should be noted that the size and weight of an item that can safely be handled will depend on the strength and physique of the individual. The ability to handle loads when seated is much less than when standing since the whole of the lifting load is taken by the back muscles in the lumbar region. 

Strengthening techniques can reverse aging s effects on muscles. A strong back, firm abdomen, lean arms, and sturdy legs help you function not only under normal conditions, but abnormal conditions as well—that is, when you need an extra burst of energy or strength in an emergency. 

Previous trauma or certain medical conditions involving bones, joints, muscles, tendons, nerves, and blood vessels can also contribute to back-related disorders. Psychological factors, such as stress, may influence the reporting of injuries, pain thresholds, and even the speed or degree of healing. Physically fit individuals tend to have fewer and less severe injuries. Remember to consult with a physician or physical therapist about which aerobic, strength, and flexibility exercises to do. This is especially important for those individuals who have preexisting injuries or medical conditions. 

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