Physical performance, pain and pool exercise in individuals with late effects of polio

Abstract

The overall purpose of the studies was to obtain knowledge about physical performance and related factors in individuals with late effects of polio. The specific aims were to provide a description of pain and how it is related to the effects of polio and the physical activity of the individual; to evaluate physical performance, the effect of reduced muscle strength on walking performance, and to study the impact of pool exercise. The subjects included in the studies comprised 234 individuals, 146 women and 88 men. They had all been to a first visit at the polio unit at Sahlgrenska University Hospital. The overall inclusion criteria were experience of the late effects of polio and being a walker with or without devices.Study I: Presence and intensity of pain and pain characteristics were assessed in thirty-two individuals, and were correlated to the level of physical exertion, muscle strength in the knee extensors during 30 m walking, and to the level of distress as measured by the Nottingham Health Profile (NHP). Pain was most common due to physical activity during leisure time. Cramping pain was the most common type of pain in the lower limbs regardless of polio affection or not. In the trunk and upper limbs aching was most marked. The level of pain intensity correlated positively to the level of physical exertion, to walking speed and to five of six dimensions in NHP, but not to the degree of muscle weakness. Study II: Another 32 individuals were recruited for this study. An exercise test on a bicycle ergometer was performed, and isokinetic muscle strength in knee extensors and knee flexors were measured. A strong correlation was found between the muscle measurements with peak workload and peak oxygen uptake from the exercise test. Individuals with weak muscles and low peak heart rate would benefit from peripheral muscle endurance training, and those with relatively stronger muscles from a general aerobic exercise program.Study III: The 234 individuals with late effects of polio were included and 143 clinically healthy subjects were used for comparison. The values from eight strength measurements were transformed into an index. The index was used together with spontaneous and maximal walking speed from 30 m walking, to develop a model for analysis of non-linear regression. A specific strength threshold could not be identified, but rather a gradual flattening of the curve. The asymptote for maximal walking was higher in the healthy group than in the group with late effects of polio, but it occurred at approximately the same strength index. A high BMI lowered the asymptote for both groups. In the polio-group those walking with assistive devices were slower walkers.Study IV: A general dynamic five months exercise program in heated water was studied. There were no differences in peak workload, peak VO2, and peak heart rate after training compared to a control group. At the same workload after training, the heart rate was significantly lowered for the training group compared to the controls. A reduction of pain experience was seen in the training group. No negative effects were seen.Study V: To gain an understanding of the participants experiences of the training in water an interview study was carried out and analysed according to the phenomenographic approach. Fourteen different categories appeared focusing on three different aspects of exercising in water: the self, the training situation and the world around. The self includes the body, the mind or the body related to the mind. The training situation includes the group, the water or the leader and the world around situations outside the training situation.Conclusions: The experience of pain was related to physical activity in daily life. Decreased muscle function was a major factor negatively influencing physical performance as shown in the ergometer test and in walking capacity. Evidence was provided for a non-linear relationship between walking speed and muscle strength in both healthy subjects and in persons with late effects of polio. Exercise training in water resulted in a lower heart rate at submaximal workload and less experience of pain. The training was experienced as being good for the body, but also influenced both self-confidence and sociality.