Kenneth H. Pitetti

Physical Activity for the Chronically Ill and Disabled

Exercise prescription principles for persons without chronic disease and/or disability are based on well developed scientific information. While there are varied objectives for being physically active, including enhancing physical fitness, promoting health by reducing the risk for chronic disease and ensuring safety during exercise participation, the essence of the exercise prescription is based on individual interests, health needs and clinical status, and therefore the aforementioned goals do not always carry equal weight. In the same manner, the principles of exercise prescription for persons with chronic disease and/or disability should place more emphasis on the patient’s clinical status and, as a result, the exercise mode, intensity, frequency and duration are usually modified according to their clinical condition. Presently, these exercise prescription principles have been scientifically defined for clients with coronary heart disease. However, other diseases and/or disabilities have been studied less (e.g. renal failure, cancer, chronic fatigue syndrome, cerebral palsy). This article reviews these issues with specific reference to persons with chronic diseases and disabilities.

Promotion of Physical Fitness and Prevention of Secondary Conditions for Children With Cerebral Palsy: Section on Pediatrics Research Summit Proceedings

Inadequate physical fitness is a major problem affecting the function and health of children with cerebral palsy (CP). Lack of optimal physical activity may contribute to the development of secondary conditions associated with CP such as chronic pain, fatigue, and osteoporosis. The purpose of this article is to highlight the content and recommendations of a Pediatrics Research Summit developed to foster collaborative research in this area. Two components of physical fitness—muscle strength and cardiorespiratory fitness—were emphasized. Although there is evidence to support the use of physical fitness interventions, there are many gaps in our current knowledge. Additional research of higher quality and rigor is needed in order to make definitive recommendations regarding the mode, intensity, frequency, and duration of exercise. Outcome measurements have focused on the body functions and structures level of the International Classification of Functioning, Disability and Health (ICF), and much less is known about effects at the activities and participation levels. Additionally, the influence of nutritional and growth factors on physical fitness has not been studied in this population, in which poor growth and skeletal fragility have been identified as serious health issues. Current intervention protocols and outcome measurements were critically evaluated, and recommendations were made for future research.

Research on physical activity and disability: an emerging national priority.

Despite the voluminous amount of research that has been published in the field of exercise science over the past three decades, there remains a paucity of information on the activity patterns and physiological responses to exercise in persons with disabilities. In an era when physical activity has grown to new heights in terms of its importance in promoting health and preventing disease, many questions pertaining to how it affects the lives of individuals with physical disabilities remain unanswered. The purpose of this paper is to review the prevalence of disability in the United States and to present recommendations for future research on physical activity and disability. A related objective of this paper is to encourage exercise scientists to undertake research on this increasingly significant group of American citizens.

Physical fitness and adults with mental retardation. An overview of current research and future directions

SummaryThe deinstitutionalisation movement of the past 25 years has focused on the placement of people with mental retardation into community-based settings. There is a need for exercise- and health-related professionals to demonstrate a thorough understanding of the term mental retardation and all of the intellectual and behavioural ramifications that coexist with this condition before addressing the ‘how to’ of fitness evaluation. Therefore, the article outlines the range of intellectual and behavioural characteristics of this population, based on the level of retardation.Many researchers investigating body composition have reported that a disproportionate number of adults with mental retardation carry a percentage of body fat that would be considered unhealthy (e.g. it increases the risk of early onset of such diseases as hypertension and adult onset diabetes mellitus). Living arrangements (i.e. institution vs smaller residences) play a role in the prevalence of obesity. Many attempts of researchers to control weight in adults with mental retardation through caloric restriction, exercise, and a combination of diet and exercise, have had a varied outcome.Cardiovascular capacity is considered by most exercise physiologists as the major physiological indicator for overall fitness. The majority of researchers who have evaluated the cardiovascular fitness levels of adults with mental retardation have reported fitness levels representative of a very sedentary population. Therefore, one would expect a keen sense of urgency among researchers to develop training regimens targeted specifically for people with mental retardation. Many have been developed, but to date only 2 cardiovascular training regimens have been reported that specifically describe the necessary components of an exercise programme (i.e. frequency, duration, intensity) that would allow for reproducibility — a stationary bicycle routine using the Schwinn ‘Air-Dyne’ ergometer and a run/walk programme. Of these, only the programme using the Schwinn ‘Air-Dyne’ ergometer reported significant improvements in cardiopulmonary fitness.Researchers have demonstrated that: (1) body strength is valuable for recreation activities and activities of daily living; (2) competence in upper body muscular skills is a prerequisite for many available vocational opportunities; and (3) positive correlations have been established between muscular strength and industrial work performance in people with mental retardation. Therefore, there is a need for appropriate evaluation procedures for determining the muscular strength and endurance of people with mental retardation.The future directions for researchers and professionals concerned with the fitness status of people with mental retardation includes answering question such as: What will be the effect of obesity on general health status? Can high risk profiles for cardiovascular and metabolic diseases because of poor fitness and high incidences of obesity be altered through lifestyle modifications in this population? These and other questions are raised in the hope that future research will address these issues that are important not only for the general welfare of people with mental retardation, but also for the professionals who care for this population.

Mentally retarded individuals--a population at risk?

When comparing the aging process of mentally retarded (MR) persons with the nondisabled population, researchers have established an earlier lower limit for the onset of old age for MR persons and a higher mortality rate. The reason for early senescence has not been successfully resolved, but the finding that cardiovascular disorders are the most prevalent form of disease among elderly MR persons suggests a relationship between lifestyles and higher mortality rate. Indeed, studies that evaluated the cardiovascular fitness (CVF) of MR individuals demonstrated substandard levels of fitness. The results of these studies, however, are not conclusive due to variation in test methodologies, motivational factors, and issues of test validity and reliability. Training studies which have purported to determine trainability of this population have also shown confusing results, perhaps attributed to the same protocol inconsistencies. Therefore, the purposes of this article are 1) to review previous methods of evaluating CVF of MR adults and determine whether testing methodologies invalidate the results of these studies, 2) to review training studies involving adult MR individuals and determine whether this population is capable of improving their CVF, and 3) to identify areas where further research is needed to fully describe the functional cardiovascular characteristics of MR adults.

Validation of cardiovascular fitness field tests in children with mental retardation

The validity of the 600-yard walk/run, the 20-m shuttle run, and a modified 16-m shuttle run was determined to measure aerobic capacity (VO2peak) in children with mild and moderate mental retardation. Practice sessions for all tests were conducted. All field tests were very reliable, and VO2peak was significantly related to them all. A stepwise multiple regression showed that field test performance, body mass index (BMI), and gender, but not age, were also significant predictors of VO2peak. All field tests were valid and reliable indicators of aerobic capacity, suggesting that these tests can be used to predict VO2max in children with mild and moderate mental retardation.

Peak Torque, average power, and hamstring/quadriceps ratios in nondisabled adults and adults with mental retardation

OBJECTIVE To compare isokinetic hamstring and quadriceps peak torque (Nm), average power (watts), and corresponding hamstring/quadriceps (HQ) ratios (as percentages) of adult men with Down syndrome(DS), with mental retardation without Down syndrome (NDS), and nondisabled sedentary controls (SC). DESIGN Repeated measures analysis of variance. SETTING Subjects were tested at a university exercise science laboratory. SUBJECTS Volunteer sample of 35 subjects: SC(n=13), DS(n=9), and NDS (n=13). INTERVENTION Subjects performed isokinetic strength tests at 60 degrees /sec and 90 degrees/sec using gravity effected torque procedures. Subjects with DS and NDS performed the test on two separate days with best results selected for statistical comparisons. Sedentary controls performed the test once. MAIN OUTCOME MEASURES Isokinetic hamstring and quadriceps peak torque and average power, and corresponding HQ ratios on a Cybex 340 isokinetic dynamometer. RESULTS In all isokinetic parameters measured, sedentary controls demonstrated significantly higher scores than subjects with DS and NDS. There was no significant difference between subjects with DS and NDS, although mean peak torque and average power scores were greater in subjects with NDS. Finally, there were no significant differences in peak torque and average power HQ ratios across groups (p> .01), although group mean peak torque HQ ratios were greatest for sedentary controls (range=61% to 63%) and approximated accepted HQ ratio norms, and lowest for subjects with DS(range=40% to 46%). CONCLUSIONS Individuals with mental retardation are in need of progressive resistance exercise programs to improve hamstring and quadriceps strength and normalize HQ strength and power ratios.

Effects of Traditional Treatment and Partial Body Weight Treadmill Training on the Motor Skills of Children With Spastic Cerebral Palsy A Pilot Study

Purpose: This study was designed to examine the effects of intensive traditional physical therapy treatment methods combined with partial body weight treadmill training (PBWTT) on motor and ambulatory skills of children with cerebral palsy. Methods: Five children (2.3 to 9.7 years) with cerebral palsy participated in a therapy program for four weeks, three to four sessions per week, for two hours per session. Outcomes were measured using the Gross Motor Function Measure, Pediatric Evaluation of Disability Inventory, pedographs, and the Timed 10-Meter Walk Test. Results: Wilcoxon paired-sample tests and percent changes showed a significant (p < 0.05) decrease in mean step length differences. Results indicate improvements in motor and ambulatory skills of individual children indicating positive measurable outcomes of intensive physical therapy with partial body weight treadmill training. Conclusions: An intensive episode of physical therapy of reasonable frequency and duration that includes partial body weight treadmill training may be effective in improving motor skills of children with spastic CP.

Effects of an Aerobic Rowing Training Regimen in Young Adults With Down Syndrome

Effects of a rowing exercise regimen on cardiovascular fitness of young adults with Down syndrome were examined. Sixteen young males with trisomy 21 (mean age 21.3, mean IQ 38.8) were randomly assigned to either a control or exercise group. All participants performed pre- and posttraining graded exercise tests on a treadmill and rowing ergometer. The exercise group performed a 16-week rowing ergometry training regimen. Following training, no changes in cardiovascular fitness had occurred for this group. However, they reached significantly higher levels of work performance for both treadmill and rowing ergometer posttraining tests. Results show that an exercise training regimen did not improve the cardiovascular fitness of young adults with Down syndrome but did improve exercise endurance and work capacity.

Effects of a minimally supervised exercise program for mentally retarded adults.

Previous exercise studies that attempted to improve the cardiovascular fitness (CVF) of mentally retarded (MR) adults were flawed with methodological shortcomings that prevented conclusive results. At issue in these training studies were fitness test validity and reliability, exactness of duration and intensity of training, and an inordinate amount of supervision. Therefore, we sought to determine whether moderately MR adults (seven males, five females; IQ = 61 +/- 3, age = 25 +/- 3 yr) could improve their CVF through a minimally supervised 16-wk training program. Each subject repeated exercise tests twice on two different modes of exercise, the treadmill (TM) and Schwinn Air-Dyne ergometer (SAE), before training to ensure validity and reliability of initial CVF levels. Intensity and frequency of exercise were closely monitored. An observer was present during the training bouts, but, following initial instructions, no additional encouragement or instructions were given. Although the training program significantly increased peak VO2 (29.2 +/- 8 to 33.5 +/- 9 ml.kg-1.min-1) and peak ventilation (73 +/- 26 to 81 +/- 231.min-1) when assessed on the TM, significant changes in these same parameters were not seen when assessed on the SAE. The importance of these results was discussed.