1. Persons in wheelchairs often have overdeveloped anterior shoulder muscles (pectoralis major and minor, anterior deltoid) from pushing their chair (Lockette, 1995). This is usually accommodated by overstretched back musculature from chronic sitting. The fitness instructor should develop strength in the shoulder abductors, adductors, retractors, elevators and depressors, to assure greater 'balance' between the anterior and posterior musculature. Since there is greater likelihood that overloading the anterior muscle groups from wheeling the chair could result in an overuse injury, it is important to not overwork these muscle groups unless they are low in strength. Pain or soreness 24 to 48 hours after activity is an indication that the joint and muscle group may have been excessively loaded.
Overuse of certain muscle groups can also cause stress fractures or cumulative trauma disorders. Manual wheelchair users are particularly prone to rotator cuff tears, lateral epicondylitis, and carpal tunnel syndrome, which result from repetitive motions to small muscle groups as a result of propelling the wheelchair (Cooper et al., 1999).
2. Transfers and seated push-ups (used to prevent pressure sores) are essential movements that should be performed several times a day. Two important muscle groups that are needed to perform these tasks are the triceps and biceps brachii. The fitness instructor should make this a primary goal of the resistance training program. Improved strength in these muscle groups is also very important for getting up from the floor. Persons with balance impairments, such as cerebral palsy and multiple sclerosis have a higher incidence of falls and will occasionally have to lift themselves up from the floor.
3. Many individuals who use wheelchairs have poor trunk musculature (Rimmer, 1994). This often requires the person to wear some type of strap or harness to prevent them from falling out of the chair. The fitness instructor should evaluate upper trunk stability by having the person flex their spine while sitting in the chair and then returning to the straight-up position. If the individual has difficulty performing this task, it may be necessary for the client to wear a chest strap that attaches to the back of the wheelchair in order to maintain good trunk stability. These straps or belts can be purchased in most medical supply stores.
4. Persons who use wheelchairs will often exhibit poor sitting posture. It is important for the fitness instructor to remind the client not to slump in his or her chair. Emphasize good sitting posture while performing the resistance training program. Mirrors will often facilitate good body awareness and might assist the client in becoming more aware of his or her sitting posture. If the individual is unable to maintain good posture, it may be necessary to work with a physical therapist or physician in devising ways to improve posture. Sometimes it is necessary to facilitate improved sitting posture by having a rehabilitation engineer or assistive technology specialist design a seat cushion that supports the weak side of the body.
5. Establishing and maintaining optimal range of motion in the affected limbs is paramount. Wheelchair users often have limited range of motion from sitting in the chair for long periods of time and will therefore need a complementary flexibility program. It is important for the fitness instructor to understand the limitations in range of motion at certain joints resulting from wheelchair use (i.e., spasticity). Muscle groups that are severely shortened (contractures) may need to be strengthened using isometric exercise.
6. Some individuals with severe physical disabilities may have difficulty performing the correct breathing pattern during the resistance training program (exhaling while raising the weight and inhaling while lowering it). With certain progressive disorders, such as multiple sclerosis and post-polio syndrome, breathing may worsen at various stages in the person's life. During the initial training phase, teach the client the appropriate breathing technique with little or no resistance until the person becomes accustomed to performing it correctly. Because resistance training requires a substantial increase in breathing rate and volume, diaphragmatic and pursed lip breathing is recommended for clients who have difficulty maintaining a normal breathing pattern during the exercise regimen.
7. In order to use certain pieces of equipment, the fitness instructor may have to transfer individuals who are in wheelchairs to machines or the floor. Although one-person transfers are done routinely by rehabilitation professionals, they are difficult to perform and present a high risk of injury to both the instructor and client. Whenever possible, perform a two-person wheelchair transfer. Guidelines on how to transfer clients can be found in Baxter and Lockette (1995) or Rimmer (1994). General information on wheelchair safety is listed in Table 3.