Conditions Associated with Physical Disabilities
Because of the extensive medical nature of many physical disabilities, it is important for the fitness instructor to understand the associated conditions that accommodate the disability. Since many persons with physical disabilities often have weakness or paralysis to a certain part of the body, it is important for the instructor to understand the terminology used to define movement limitations. A few of these terms are defined in Table 1.
- Some physical disabilities are classified as progressive in nature. This means that the condition will worsen over time. Some forms of multiple sclerosis and post-polio syndrome are considered progressive disorders, while other conditions, such as cerebral palsy and spinal cord injury are considered non-progressive. Progressive disorders will require more careful monitoring to assure that the resistance training program is not causing the condition to worsen, which is referred to as an exacerbation.
- Persons with physical disabilities often exhibit asymmetrical weakness. Many individuals with cerebral palsy or stroke have hemiplegia (weakness or paralysis on the right or left side of the body), which results in significant differences in strength between the stronger side and weaker sides of the body. It is important to improve the affected side as much as possible without neglecting the non-affected side. There may be circumstances in which the nerves controlling the affected side have been partially or completely damaged. When this occurs, the magnitude of improvement in the affected muscle groups will be greatly reduced. However, if there is still some nerve innervation on the weakened side, a resistance training program should result in some measurable improvement in strength. Having hemiplegia may require active-assistive resistance exercise on the affected side while using standard exercises on the non-affected side.
- Spasticity is a general term used to describe various types of rigid or hypertonic muscle tone. It results in an exaggerated contractile response to stretch. It is often seen in persons who have damage to their central nervous system, such as individuals with cerebral palsy, stroke, multiple sclerosis and spinal cord injury. The condition occurs in one of three ways: (a) loss of control from the damaged portion of the brain or spinal cord; (b) hypersensitivity of nerve receptors that are no longer being supplied with control after the injury; or (c) growth of new nerve pathways (Lockette & Keys, 1994, p. 95). The amount of spasticity that a person has could be mild, moderate or severe.
Spastic muscles are very rigid and are often accompanied by a 'clasped-knife' position, which refers to the arm or leg maintaining a flexed position. Some individuals will have severe spasticity, which often makes it difficult or impossible to extend the limb. Severe spasticity usually results from the muscle groups being placed in a fixed position for a significant period of time resulting in a contracture. Contractures can often be stretched except in severe cases where the muscle group is permanently shortened.
Since many individuals with physical disabilities will have some degree of spasticity (tightness), flexibility training should always be combined with resistance training. It is important for the instructor to identify the 'spastic' muscle groups and develop a long-range plan to increase range of motion. If the joint has been in a 'fixed' position for many years, or if the spasticity is severe, it may not be possible to fully extend the joint. The instructor should consult with a physical therapist, physician or appropriate medical professional to determine how to stretch a spastic muscle without causing injury. As with resistance training, use active-assistive stretching for certain muscle groups that are too weak (paresis) or tight (spasticity) to be moved independently. Additional guidelines for working with spasticity are noted in Table 2.
- Some individuals with physical disabilities develop contractures, which are shortened muscle groups and connective tissues surrounding the joint. The muscle tone is very high, which is referred to as hypertonicity. A contracture occurs when a body part (arm or leg) is placed in a flexed position over an extended period of time (weeks or months), usually resulting from spasticity. Sometimes this cannot be avoided due to the neurological involvement, while at other times it can be prevented by constantly stretching the muscle group. Contractures may be permanent or temporary depending on the severity of spasticity and the length of time that the joint has been placed in a 'fixed' position. Some muscle groups with contractures may be able to obtain minimal improvements in strength, while others will be unable to benefit from a resistance training program. The fitness instructor should consult with a physical therapist or qualified health professional to determine if contractures can be strengthened. Flexibility training should always be integrated in the exercise prescription for persons who have contractures, since the primary problem is shortening of muscle fibers and connective tissues surrounding the joint.
- On the other end of the spectrum are persons who have flaccid (loose) or hypotonic muscle tone. This condition is often seen in persons with post-polio syndrome and some individuals with spinal cord injury and cerebral palsy. Persons with hypotonic muscle tone may or may not have enough nerve innervation to obtain improvements in strength. If there is some nerve innervation, the hypotonic muscle groups will be very weak and will require a great amount of work.
- Some individuals with neurological conditions (i.e., multiple sclerosis, post-polio syndrome) get progressively weaker as they age. This may be related to the condition or could be associated with an inactive lifestyle compounded by the aging process. Consult with the client's physician if you are concerned about a noticeable decline in strength.
- At certain times in the person's life, it may be necessary to temporarily stop the training program because of an exacerbation. Exacerbations occur most often in persons with multiple sclerosis. These can occur frequently or infrequently depending on the amount of involvement. After an exacerbation, it will often be necessary to start out at a much lower resistance because of the complications that resulted from the exacerbation. Upon resuming activity, the fitness instructor should contact the client's physician to determine the appropriate training progression. Although the person may be unable to reach a prior level of strength before the exacerbation, it is important that the fitness instructor reassure the client that strength levels can be improved. Clients who have exacerbations should understand that they begin with a 'new slate' and that the goal is to always attain the highest strength level possible.
- Damage to sensory nerves occurs with many types of physical disabilities. This results in the inability to detect pressure against the skin, which, if left untreated, could result in a pressure sore (Baxter & Lockette, 1995). A pressure sore is an area of damage to the skin and underlying tissues resulting from unrelieved pressure and inadequate circulation (Constable & Pierce, 1977). Since many people with physical disabilities who wear braces or use wheelchairs have a high risk of incurring a pressure sore, it is extremely important that they frequently check all parts of their body for skin irritations that may result from a new resistive exercise or piece of equipment. These injuries often start with a small area of redness (about the size of a quarter) and then gradually get larger if untreated.
- Depending on the disability, muscle groups may be functional, partially functional (paresis), or nonfunctional (paralysis). The fitness instructor will need to obtain information on which muscle groups' fall into each category. There may also be some joint irregularity that needs to be considered in the exercise prescription. For example, individuals with cerebral palsy often have hip dislocations due to the strong pull of the adductor muscles. If there has been a history of hip displacement, the instructor would need to check with the client's physician to determine if modifications need to be made to the resistance training program.
- It is important to keep detailed records on each client. Since there are often several associated conditions that accommodate a physical disability (i.e., spasticity, hypertension, joint pain, exacerbations, pressure sores), the fitness instructor should maintain current records and note any new medical conditions that may develop during the training program.
- Progressive disorders will often result in a gradual loss of muscle mass and strength. When muscle soreness occurs in persons who have a progressive condition, it may be an indication that the overload or intensity was excessive. Although it has not been well established in the research literature, the general assumption is that this could lead to a permanent loss of strength (Lockette & Keys, 1994). Until more research is conducted, it is important for the instructor to be extremely cautious when working with individuals who have progressive disorders. Get approval and recommendations from the client's physician for the optimal training volume and specific resistance exercises that may prevent injury to the client.
- Individuals who have physical disabilities must overcome the physical and psychological challenges of living with a disability. This often results in bouts of depression, which is a common association condition in persons with physical disabilities. The fitness instructor must be aware of any signs of depression and contact the client's physician or health care provider if it becomes evident that the client is struggling with this condition. Occasionally, the person may drop out of the program because of the severity of the depression.