Many post-polio patients probably had significant weakness from their initial poliomyelitis illness of which they were unaware. The average post-polio patient with normal muscle strength, as determined by manual muscle testing, had a 50% deficit in strength when measured quantitatively using isokinetic equipment. (17)

Strength and endurance testing by Agre (18) revealed that an unstable post-polio group had significant deficits in strength, isometric work capacity, and ability to recover strength after exhausting activity. On average the unstable group, defined as having more severe initial poliomyelitis as evidenced by a much greater length of hospitalization, had one-half the strength and work capacity of the normal subjects. The subjective time to recover completely from the fatiguing exercise was found to be much longer than in the stable and control groups, taking 2-3 days to recover from the fatiguing activity.

The conclusion of study done by Kilfoil and Pierre, (19) demonstrates that serial isokinetic strength assessment is a reliable method for measurement of muscular performance in subjects with PPS. However, it is recommended that a sufficient number of test sessions be conducted to establish a stable baseline of performance on this particular patient sample in order to examine the effect of a therapeutic intervention. It is proposed that a Cybex II isokinetic device, if used appropriately, can measure clinical change and may be used to examine the effect of various treatment interventions to ameliorate strength in persons with PPS.

Endurance or aerobic exercises have increased cardiopulmonary performance in postpolio subjects as evidenced by significant increases in aerobic capacity, VO2 max. Following 60 minutes exercise sessions 2 times per week for 22 weeks a cardiovascular training effect was seen in most subjects, as the heart rate at a submaximal workload decreased after training. (20) The conclusions from this study indicate that postpolio subjects may benefit from an endurance training program and that there appears to be no harmful short-term effects in the muscle. The program used, emphasized submaximal resistance exercises, which may be one of the explanations for the limited training effect on muscle strength. In this study the exercise programs lasted for 60 minutes and consisted of 5 minutes of general warm-up followed by low-resistance, high-repitition exercise for all major muscle groups in both upper and lower extremities as well as the trunk. After 1 month of training, 5 minutes of exercise on a bicycle was included at approximately 60% to 80% of maximal heart rate. The amount of time on the bike remained at 5 minutes at each session A 5 minute cool-down period followed at the end of each session.

The recent studies have shown that exercise can improve muscle strength, cardiorespiratory fitness, and the efficiency of ambulation in PPS patients. It may also add to the patients sense of well-being. The benefits appear to occur when the patients stay within reasonable bounds while exercising in order to avoid overuse problems. In particular, the patients should be instructed to avoid activities that cause increasing muscle or joint pain or excessive fatigue, either during or after their exercise program. The literature indicates that exercise within these constraints leads to a number of beneficial physiologic and psychologic adaptations in patients with postpolio syndrome. Judicious exercise should be viewed as an important adjuvant in the overall therapeutic program of the patient. (17)

Compliance with clinical recommendations is a concern with any patient. In a two year follow up study of PPS patients, Peach and Olejnik, (21) looked at the compliance to prescribe items of orthotic use, lifestyle changes, weight loss, decrease in work hours, and aerobic exercise. The compliers noted an improvement or resolution to their complaints of weakness, fatigue, and muscle pain. At the two year follow-up they had no loss in strength. The other two groups were rated as either partial or noncompliers. The partial compliers had a strength loss over the two years of an average of 1.3% annually, and the noncompliers decreased at an annual average rate of 2%. It was concluded that compliance with clinical recommendations significantly reduced symptomatology in PPS patients and also appeared to reduce the rate of loss in strength over time.

Patients with PPS have unique problems which need to be considered when prescribing an exercise program for an individual patient. Because of the variability in which the motor nurons to different muscle groups may have been affected and the scattered weakness that may be present. The challenge in prescribing exercise for the patient with PPS comes in recognizing these unique factors in each patient and modifying the prescription accordingly. One must protect muscles and joints experiencing the adverse effects of overuse or body areas with very significant chronic weakness while exercising those body areas experiencing the deleterious effects of disuse. (17)

Moderation of daily activities also appears to be prudent. Interspersing intervals of activity with short intervals of rest to avoid excessive fatigue appears to be very beneficial for these patients. (17) Work capacity and strength recovery were increased and local muscle fatigue was decreased with pacing. (22) Excessive fatigue is to be avoided due to the increased difficulty recovering from exhausting activity.

In the research and completion of this project, I have learned that patients with PPS have unique problems which need to be considered when prescribing an exercise program for an individual patient. The challenge in prescribing exercise for the patient with PPS comes in recognizing the unique factors in each patient and modifying the prescription accordingly. I have also learned that you can not believe all of the reports that have been made and some of the invalidated information that is out there. This includes the previous ideas or thoughts on treatment for PPS patients which were to decrease all activity, avoid any exercise and to conserve their energy. These patients are already weaker to begin with (up to 60% compared to normal) and disuse will continue to contribute to their decline in strength. Research has shown the exercise programs allow these patients to have strength gains and to be able to avoid the steady decline in function as they age and their bodies continue to deal with the effects of having been infected with the poliomyelitis virus.