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Physical activity for people with a disability: a conceptual model.

The promotion of a physically active lifestyle has become an important issue in health policy in first-world countries. A physically active lifestyle is accompanied by several fitness and health benefits. Individuals with a disability can particularly benefit from an active lifestyle: not only does it reduce the risk for secondary health problems, but all levels of functioning can be influenced positively. The objective of this article is to propose a conceptual model that describes the relationships between physical activity behaviour, its determinants and functioning of people with a disability. The literature was systematically searched for articles considering physical activity and disability, and models relating both topics were looked for in particular. No models were found relating physical activity behaviour, its determinants and functioning in people with a disability. Consequently, a new model, the Physical Activity for people with a Disability (PAD) model, was constructed based on existing models of disability and models of determinants of physical activity behaviour. The starting point was the new WHO Model of Functioning and Disability, part of the International Classification of Functioning, Disability and Health (ICF), which describes the multidimensional aspects of functioning and disability. Physical activity behaviour and its determinants were integrated into the ICF model. The factors determining physical activity were based mainly on those used in the Attitude, Social influence and self-Efficacy (ASE) model. The proposed model can be used as a theoretical framework for future interventions and research on physical activity promotion in the population of people with a disability. The model currently forms the theoretical basis for a large physical activity promotion trial in ten Dutch rehabilitation centres.

Attitude↗

[The role of physical rehabilitation in the treatment of exudative pleurisy].

INTRODUCTION: Exudates are due to a variety of diseases, the major and most common ones being tuberculosis, nonspecific inflammation and malignancy. They are usually treated conservatively, sometimes combined with surgery and physical treatment. Physical therapy includes positional exercises, breathing exercises and biostimulation. AIM OF THE STUDY: The study was aimed to find out the following: 1) Is lung function improved by physical therapy; 2) Can adhesions be diminished and mobility of the affected hemidiaphragm improved by physical treatment; 3) Is there a direct positive correlation between physical treatment and obtained improvement, or the same can be achieved in patients receiving medicamentous treatment only; 4) What are the effects of some factors we cannot influence (sex, age, effusion level, position of adhesions) on lung function and diaphragm mobility improvement, that is on the efficiency of physical treatment; 5) How do the factors we can influence (the time interval before initiating the treatment and its duration) affect improvement of the same lung function parameters, that is treatment efficacy? MATERIAL AND METHODS: Physical treatment of patients with exudative pleurisy was accomplished at the Department of Rehabilitation in our Institute and it consisted of directed breathing exercises and laser biostimulation. Its effects were examined in a group of 175 patients, who received both conservative and physical treatment, and results were compared with the control group patients, treated only conservatively (with antibiotics, antituberculotics, corticosteroids). RESULTS: Comparative analysis confirmed a significant improvement of lung function parameters (VC, FEV1, PEF) as well as of hemidiaphragm mobility on the affected side of the thorax in favour of the examined group. The severity of the lung function and diaphragm mobility impairments have been found to be in correlation with the localization of adhesions, whereas the degree of improvement correlated with the time interval before the treatment initiation, as well as with its duration. DISCUSSION AND CONCLUSION: The applied physical therapy resulted in: 1) significant improvement of all examined lung function parameters in the examined group, which was not registered in the control group; 2) significant improvement of the diaphragm mobility in general; 3) factors such as sex, age and effusion level have no effects on the physical treatment results; 4) treatment results are affected by the time interval passed before the treatment initiation and its duration, as well as the localization of adhesions; anterior adhesions affected lung function and diaphragm mobility least, posterior ones more, while the influence of lateral adhesions was most significant. It is finally concluded that physical treatment should necessarily be included in the treatment of exudative pleurisy.

Adult↗

Beneficial associations of physical activity with 2-h but not fasting blood glucose in Australian adults: the AusDiab study.

OBJECTIVE: We examined the associations of physical activity with fasting plasma glucose (FPG) and with 2-h postload plasma glucose (2-h PG) in men and women with low, moderate, and high waist circumference. RESEARCH DESIGN AND METHODS: The Australian Diabetes, Obesity and Lifestyle (AusDiab) study provided data on a population-based cross-sectional sample of 4,108 men and 5,106 women aged >or=25 years without known diabetes or health conditions that could affect physical activity. FPG and 2-h PG were obtained from an oral glucose tolerance test. Self-reported physical activity level was defined according to the current public health guidelines as active (>or=150 min/week across five or more sessions) or inactive (<150 min/week and/or less than five sessions). Sex-specific quintiles of physical activity time were used to ascertain dose response. RESULTS: Being physically active and total physical activity time were independently and negatively associated with 2-h PG. When physical activity level was considered within each waist circumference category, 2-h PG was significantly lower in active high-waist circumference women (beta -0.30 [95% CI -0.59 to -0.01], P = 0.044) and active low-waist circumference men (beta -0.25 [-0.49 to -0.02], P = 0.036) compared with their inactive counterparts. Considered across physical activity and waist circumference categories, 2-h PG levels were not significantly different between active moderate-waist circumference participants and active low-waist circumference participants. Associations between physical activity and FPG were nonsignificant. CONCLUSIONS: There are important differences between 2-h PG and FPG related to physical activity. It appears that 2-h PG is more sensitive to the beneficial effects of physical activity, and these benefits occur across the waist circumference spectrum.

Adult↗

Psychosocial correlates to high school girls' leisure-time physical activity: a test of the theory of planned behavior.

This study was designed to test the efficacy of the theory of planned behavior in predicting intention to engage in leisure-time physical activity and leisure-time physical activity behavior of high school girls. Rating scales were used for assessing attitude to leisure-time physical activity, subjective norm, perceived control, and intention to engage in leisure-time physical activity among 129 ninth through twelfth graders. Leisure-time physical activity was obtained from 3-wk. diaries. The first hierarchical multiple regression indicated that perceived control added (R2 change = .033) to the contributions of attitude to leisure-time physical activity and subjective norm in accounting for 50.7% of the total variance of intention to engage in leisure-time physical activity. The second regression analysis indicated that almost 10% of the variance of leisure-time physical activity was explicated by intention to engage in leisure-time physical activity and perceived control, with perceived control contributing 6.4%. From both academic and theoretical standpoints, our findings support the theory of planned behavior, although quantitatively the variance of leisure-time physical activity was not well-accounted for. In addition, considering the small percentage increase in variance explained by the addition of perceived control explaining variance of intention to engage in leisure-time physical activity, the pragmatism of implementing the measure of perceived control is questionable for this population.

Adolescent↗

Evaluation of a community-based intervention to promote physical activity in youth: lessons from Active Winners.

PURPOSE: To test the effects of a community-based physical activity intervention designed to increase physical activity and to conduct an extensive process evaluation of the intervention. DESIGN: Quasi-experimental. SETTING: Two rural communities in South Carolina. One community received the intervention, and the other served as the comparison. SUBJECTS: Public school students who were in fifth grade at the start of the study (558 at baseline) were eligible to participate. A total of 436 students participated over the course of the study. INTERVENTION: The intervention included after-school and summer physical activity programs and home, school, and community components designed to increase physical activity in youth. The intervention took place over an 18-month period. MEASURES: Students reported after-school physical activity at three data collection points (prior to, during, and following the intervention) using the Previous Day Physical Activity Recall (PDPAR). They also completed a questionnaire designed to measure hypothesized psychosocial and environmental determinants of physical activity behavior. The process evaluation used meeting records, documentation of program activities, interviews, focus groups, and heart rate monitoring to evaluate the planning and implementation of the intervention. RESULTS: There were no significant differences in the physical activity variables and few significant differences in the psychosocial variables between the intervention and comparison groups. The process evaluation indicated that the after-school and summer physical activity component of the intervention was implemented as planned, but because of resource and time limitations, the home, school, and community components were not implemented as planned. CONCLUSIONS: The intervention did not have a significant effect on physical activity in the target population of children in the intervention community. This outcome is similar to that reported in other studies of community-based physical activity intervention.

Child↗

Physical symptoms and physician-experienced difficulty in the physician-patient relationship.

BACKGROUND: The practice of medicine has many expected and accepted challenges, but all physicians experience some patients as difficult to a degree that transcends these expectations. Physician-experienced difficulty is associated with a syndrome of three characteristics: patient psychopathology, abrasive interpersonal styles, and multiple physical symptoms. OBJECTIVE: To assess the roles played by the number of physical symptoms and by specific symptoms in determining whether physician-experienced difficulty occurs. DESIGN: New analyses of epidemiologic survey data from the Primary Care Evaluation of Mental Disorders (PRIME-MD) 1000 Study. SETTING: Four primary care clinics. PARTICIPANTS: 627 ambulatory patients seen by 27 physicians. MEASUREMENTS: Physician-experienced difficulty was measured by using the 10-item Difficult Doctor Patient Relationship Questionnaire (DDPRQ-10); patient-reported physical symptoms and physician-assessed psychopathology and somatoform symptoms were evaluated by using the PRIME-MD; and physical illnesses were measured by using a physician questionnaire. RESULTS: The number of physical symptoms and the number of somatoform symptoms correlated with difficulty (r = 0.39 and r = 0.37, respectively; P < 0.001), and the correlations remained significant after adjustment for physical and mental disorders (r = 0.20 for both correlations; P < 0.001). Difficult patients were more likely to have each of 16 physical symptoms; the odds of being difficult were greater for patients with 1 of 5 particular symptoms (stomach pain, fainting, loose stools/diarrhea, palpitations, and sleep problems), even after adjustment for physical and mental disorders. All 10 items on the DDPRQ-10 were influenced by physical symptoms, particularly those items that asked about physician frustration and whether patients were manipulative and time consuming. CONCLUSIONS: The association between physical symptoms and difficulty is due in part to the association between physical symptoms and mental disorders, but symptoms also contribute independently to difficulty. The independent component of symptom-associated difficulty may be due to 1) differences between patient and physician in expectations about treatment and 2) the part that symptoms play in conferring the "sick role" on a patient.

Communication↗

[What are the associations between occupational physical activity and overweight?].

BACKGROUND: The increasing trend for obesity, together with reduced occupational physical activity in Norway, led us to study the association between work activity and body mass index. MATERIAL AND METHODS: We analysed data from population screenings in Norwegian counties 1974-97. Occupational physical activity was measured by a question with four alternative answers. RESULTS: Among women, sedentary or light physical work was associated with the lowest body mass indices and heavy physical work with the highest. Among men, occupational physical activity was associated with a slightly higher body mass index in general, but not in all counties and not in men who were physically inactive in their leisure time. In the survey in Nord-Trøndelag 1995-97 the body mass index in men was lower in those with physical work than in those with sedentary occupations. INTERPRETATION: The inverse association between physical work and overweight does not indicate an important role of physical work in weight control of women. In men, several explanations are possible. One interpretation is that physical work is of importance for weight control in some rural areas and in men with physical activity in their leisure time.

Adult↗

Biopsychological, affective and cognitive responses to acute physical activity.

BACKGROUND: To investigate, based on biopsychological arousal theory, the influence of physical activity intensity on biopsychological, affective and cognitive function. METHODS DESIGN: Repeated measures experiment involving one control and three treatment conditions. SETTING: Controlled laboratory environment. PARTICIPANTS: Twenty-one (of 27 volunteers) non-contraindicated females (55-65 years) recruited from general community and university populations completed the study. INTERVENTIONS: Data collection proceeded in four counterbalanced test-sessions including control (zero resistance), light (45%VO2max), moderate (60%VO2max), and high intensity (75%VO2max) cycle ergometer interventions. In all test sessions participants cycled at 25 W for 2 min (warm-up), followed by 10 min at the allocated intensity, and then 2 min at 25 W (cool-down). Blood pressure, heart rate and RPE were determined during test sessions. MEASURES: Energetic arousal (EA), tense arousal (TA), single dimension affect, and cognitive (reaction time-RT) responses were compared following physical activity. RESULTS: There was no significant difference in EA, TA, affect, or RT following zero resistance and light and moderate intensity physical activity or between light and moderate intensity physical activity. High intensity physical activity resulted in significantly lower levels of EA than light intensity physical activity, significantly higher levels of TA than zero resistance and light intensity physical activity, and significantly more negative levels of affect than either light or moderate intensity physical activity. There were no significant differences in reaction time between high intensity physical activity and any of the other intensities. CONCLUSIONS: There was partial support for the efficacy of biopsychological arousal theory in explaining the biopsychological and affective outcomes of physical activity, but no support for the influence of physical activity on cognitive function.

Affect↗

[Mortality associated with physical activity in leisure time, at work, in sports and cycling to work].

INTRODUCTION: Previous studies have shown that high levels of physical activity are associated with lower mortality in middle-aged men. Few studies have investigated this association in women and the independent effects of cycling to work and participation in sports. MATERIAL AND METHODS: The participants were 13,445 women and 17,441 men aged 20 to 93 years. Self-reported physical activity included general questions about leisure time physical activity and physical activity at work, sports participation, and cycling to work. Adjustment was made for blood pressure, total cholesterol, triglyceride, body mass index, smoking, and educational level. RESULTS: During 433,000 person-years of observation, 2738 women and 4672 men died. Physical inactivity during leisure time predicted mortality in both men and women in all age groups. In women and men, the most physically active in leisure time experienced only half the mortality of the sedentary. Even in the moderately and highly active persons, sports participants experienced only half the mortality of non-participants. Physical activity at work predicted mortality in women only. The men and women who rode a bicycle to work had a 39% lower risk of mortality after multivariate adjustment including leisure time physical activity. DISCUSSION: Leisure time physical activity was inversely associated with all-cause mortality in both men and women in all age groups. Benefit was found from moderate leisure time physical activity with further benefit from sports activity and bicycling as transportation. Benefit from physical activity at work was found in women only.

Adult↗

Physical impairment and disability: relationship to performance of activities of daily living in community-dwelling older men.

BACKGROUND AND PURPOSE: The decline of physical function of older adults, associated with loss of independent living status, is a major public health concern. The purpose of this study was to examine the relationship of physical impairment and disability to performance of activities of daily living (ADL) among community-dwelling older adults. SUBJECTS AND METHODS: Eighty-three community-dwelling older men who were referred to a comprehensive outpatient geriatric evaluation program (mean age=75.5 years, SD=7.0, range=64-97) were examined. Measurements of physical impairment (muscle force production, flexibility, and fitness) and physical disability (gait speed, stride length, risk for recurrent falls, and physical function) were recorded. RESULTS: A stepwise linear regression was used to determine the relationship of physical impairments and disability measures with ADL. The results indicated that walking speed, fall risk, and muscle force contributed independently to the characterization of the activities of daily living of the community-dwelling older men studied (adjusted R2=.68; F=56.81; df=3,80; P<.001). Using a principal components factor analysis, 4 domains were identified that explained 68.2% of the variance in performance of ADL: (1) mobility/fall risk=26.5%, (2) coordination=15%, (3) fitness=14.7%, and (4) flexibility=12.0%. DISCUSSION AND CONCLUSION: The identification of domains of physical function may be useful to physical therapists in the development of interventions targeted for physical impairments and disabilities that contribute to deficits in performance of ADL. Targeting interventions for physical impairments and disabilities related to function may improve the effectiveness of physical therapist interventions and reduce the loss of independence among community-dwelling older people.

Activities of Daily Living↗

Recreational physical activity and risk of prostate cancer in a large cohort of U.S. men.

Physical activity has been proposed as a modifiable risk factor for prostate cancer because of its potential effects on circulating hormones such as testosterone and insulin. We examined the association of various measures of physical activity with prostate cancer risk among men in the American Cancer Society Cancer Prevention Study II Nutrition Cohort, a large prospective study of U.S. adults. Information on recreational physical activity was obtained from a self-administered questionnaire completed at cohort enrollment in 1992/1993, as well as from a questionnaire completed as part of an earlier study in 1982. During the 9-year prospective follow-up, 5,503 incident prostate cancer cases were identified among 72,174 men who were cancer-free at enrollment. Cox proportional hazards modeling was used to compute hazard rate ratios (RR) for measures of recreational physical activity and to adjust for potential confounding factors. We observed no difference in risk of prostate cancer between men who engaged in the highest level of recreational physical activity (>35 metabolic equivalent-hours/wk) and those who reported no recreational physical activity at baseline (RR, 0.90; 95% confidence interval, 0.78-1.04; P for trend = 0.31). We also did not observe an association between prostate cancer and recalled physical activity at age 40 or exercise reported in 1982. However, the incidence of aggressive prostate cancer was inversely associated with >35 metabolic equivalent-hours/wk of recreational physical activity compared with that in men who reported no recreational physical activity (RR, 0.69; 95% confidence interval, 0.52-0.92; P for trend = 0.06). Our findings are consistent with most previous studies that found no association between recreational physical activity and overall prostate cancer risk but suggest physical activity may be associated with reduced risk of aggressive prostate cancer.

Adult↗

[Unexplained physical symptoms: a widespread problem but still low-profile in training programs and guidelines].

Unexplained physical symptoms or functional somatic syndromes that cannot be explained in terms of a defined medical disease are common. If persistent, they can cause significant distress and disability, and lead to absenteeism and social isolation as well as major health-care costs. Unexplained physical symptoms form a spectrum from transient unexplained mild physical symptoms to chronic severe somatoform disorders. Various functional somatic syndromes overlap one another substantially in symptomatology and are often resistant to conventional medical therapy. The 'Vereniging Nederlands Tijdschrift voor Geneeskunde' (Dutch Journal of Medicine Association) recently held a special conference on unexplained physical symptoms. The conclusions were: (a) patients are reluctant to accept the diagnosis of unexplained physical symptoms, because physicians do not have sufficient knowledge, expertise, and skill to diagnose and treat them, (b) patients with unexplained physical symptoms do not necessarily need to be treated by a psychiatrist except in cases of chronic and serious somatoform disorder. Patients with unexplained physical symptoms, who often have multiple and complex problems, are best treated by a team of physicians and allied paramedical professionals; (c) patients with unexplained physical symptoms can be treated effectively by specialists using cognitive behaviour therapy. Different cognitive models are available; the 're-attribution model' focuses on the re-establishment of a liveable life, while 'the consequence model' is directed at reducing the consequences of the unexplained physical symptoms. Management using the attribution model may be followed up by the consequence model approach; (d) the development of a practice guideline for the diagnosis and treatment of patients with both acute and chronic unexplained physical symptoms would improve the quality of patient care, reduce disability, increase the possibility of reintegration, and stimulate scientific research; (e) both theoretical and practical training in the diagnosing and managing of unexplained physical symptoms is inadequate in both university curriculums and postgraduate training programmes for medical specialists. Scientific research for the development of an evidence-based practice guideline is urgently needed.

Cognitive Behavioral Therapy↗

[Occupational and leisure time physical activity: trend in the Italian population].

BACKGROUND: Over the last decades a change in physical activity habits of the Italian population has been observed. The aim of this study was to compare occupational and leisure-time physical activity, to assess the relationship between physical activity and cardiovascular risk factors and the variation in cardiovascular risk profile measured 20 years apart in the Italian population. METHODS: In two populations aged 35-69 years (MATISS 1984-1987: 2041 men, 2424 women; OEC 1998-2002: 4214 men, 4206 women) gender-specific levels of occupational (occupational physical activity [OPA]-light, OPA-moderate, OPA-heavy) and leisure-time (leisure-time physical activity [LTPA]-low, LTPA-moderate, LTPA-high) physical activity were compared. Relationship between physical activity and cardiovascular risk factors was evaluated in the two samples using logistic regression models adjusted for age, heart rate, educational level and other possible confounding variables in men and women separately. The 10-year cardiovascular risk was assessed in the two periods and in different physical activity strata using the Progetto CUORE risk score. RESULTS: Comparing the two studies, prevalence of OPA-low had decreased, whereas the prevalence of LTPA-low had increased. With increasing LTPA blood pressure, heart rate and glycemia decreased, whereas high-density lipoprotein-cholesterol increased with a positive effect on obesity, smoking habit and cardiovascular risk. CONCLUSIONS: Over the last 20 years, physical activity apparently changed: currently men and women dedicate more time to physical activity during leisure-time, and are less active at work. More active people have lower levels of major cardiovascular risk factors. Societal efforts are needed to increase physical activity levels in the population.

Adult↗

Identifying supports and barriers to physical activity in patients at risk for diabetes.

INTRODUCTION: Recent clinical trials have demonstrated that increasing physical activity among patients at risk for diabetes can prevent or delay the onset of type 2 diabetes. In this study, we surveyed primary care patients at risk for diabetes to 1) describe physical activity habits, supports, and barriers; 2) identify characteristics associated with increased physical activity; and 3) develop and assess the psychometric properties of an instrument that measures influences on physical activity. METHODS: A cross-sectional sample of 522 high-risk adults who attended 14 North Carolina primary care family practices were mailed a survey about physical activity and supports of and barriers to physical activity. Risk status was determined by the American Diabetes Association's diabetes risk test. Exploratory principal components factor analyses were conducted on the influences on physical activity instrument. Predictive logistic regression models were used for the dichotomous outcome, meeting recommended Healthy People 2010 activity levels. RESULTS: Of the 258 respondents (56% response rate), 56% reported at least 150 minutes of moderate or vigorous activity per week. Higher education remained a significant demographic predictor of activity (odds ratio [OR], 1.72; 95% confidence interval [CI], 1.08-2.75). Participants were less likely to be physically active if they reported that activity is a low priority (OR, 0.45; 95% CI, 0.23-0.89), were worried about injury (OR, 0.42; 95% CI, 0.25-0.69), or had difficulty finding time for activity (OR, 0.38; 95% CI, 0.17-0.87). CONCLUSION: Participants at risk for diabetes who prioritize physical activity, make time for activity, and are less worried about injury have higher odds of being physically active. Primary care practice and community interventions should consider targeting these areas of success to increase physical activity in sedentary individuals at risk for diabetes.

Adolescent↗

The relationship among television watching, physical activity, and body composition of young children.

PURPOSE: Television watching has been reported to be associated with obesity, resting energy expenditure, and lower daily physical activity among both children and adolescents. However, most of these studies were based on self report or data collected in laboratory settings. This study examined the relationship among observed time of television watching, observed physical activity level and body composition among 3- or 4-year-old children. METHODS: African-American (41.4%), Mexican-American (23%), and Anglo-American (35.6%) children (N = 191, males = 90) from the Texas site of the Studies of Child Activity and Nutrition program were observed from 6 to 12 hours per day up to 4 days over 1 year. Activity level each minute of the day was measured with the Children's Activity Rating Scale (interobserver reliability = .84 +/- .001). The interobserver reliability of time of television watching was .96 +/- .08. RESULTS: The median of the longest number of consecutive minutes of television watching was 15 (range = 1 to 79). The median percent of minutes of television watching of total observed minutes was 14.8% (0% to 58%) and the median percent of minutes of inside minutes was 17.9% (0% to 80.9%). There were no gender or ethnic differences in time watching television or physical activity during television watching. Physical activity during television watching was lowest during the longest bout of television watching (mean = 1.48 +/- .28) compared to outside minutes (mean = 2.38 +/- .21), inside non-television minutes (mean = 1.96 +/- .13) and inside television minutes (mean = 1.65 +/- .18). The level of physical activity during television-watching times was highest (P < .0031) during October and November and lowest during March, April, June, and July. Longest bout of television watching and percent of minutes watching television to total observed minutes were inversely associated with mean physical activity, percent of minutes of physical activity levels 3, 4, or 5, and percent of physical activity levels 4 or 5. Percent of television watching to inside minutes was negatively correlated with physical activity levels 4 or 5. Television-watching behavior was not associated with body composition. CONCLUSIONS: Television watching was weakly negatively correlated with physical activity levels, and physical activity was lower during television-watching than non-television-watching time in this sample of children. Television viewing behavior was not associated with body composition.

Black or African American↗

Effects of a life skills intervention for increasing physical activity in adolescent girls.

BACKGROUND: Although adolescence is a time when physical activity levels decline, few interventions have targeted high school-aged girls in the school setting. OBJECTIVE: To evaluate the effects of a life skills-oriented physical activity intervention for increasing overall physical activity in high school-aged girls. DESIGN: Randomized controlled trial. SETTING: Baltimore magnet high school. PARTICIPANTS: A total of 221 ninth-grade girls, 83.0% of whom were African American. Intervention Participants were randomized to an 8-month physical intervention conducted in physical education class or to a standard physical education class (control). MAIN OUTCOME MEASURES: Self-reported estimated daily energy expenditure (physical activity), self-reported sedentary activities (television viewing and computer or Internet use), cardiorespiratory fitness, and selected cardiovascular disease risk factors. RESULTS: Intervention classes spent 46.9% of physical education class time in moderate to vigorous activity compared with 30.5% of time for control classes (P<.001). There were no significant between-treatment group differences for mean daily energy expenditure (P = .93), moderate-intensity energy expenditure (P = .77), or hard to very hard energy expenditure (P = .69). The proportion of participants who spent 3 or more hours viewing television during school days declined from 22.3% to 17.0% in the intervention group, but remained at 26.7% for the control group (P = .03). Both groups improved their cardiorespiratory fitness (P<.001). CONCLUSION: A life skills-oriented physical education curriculum may need to be combined with other approaches to increase the magnitude of effects on physical activity behavior in predominantly African American high school-aged girls.

Adolescent↗

Effects of recombinant human erythropoietin injections on physical self in endurance athletes.

This study examined the time course of mean self-esteem and physical self scores in three groups: male endurance athletes treated with recombinant human erythropoietin (rHuEPO group, n = 6), a placebo group (n = 5) injected with a sodium chloride solution and a control group who did not receive any injection (n = 6). Each participant completed the Physical Self Inventory twice a day (between 07.00 and 09.00 h and between 19.00 and 21.00 h). Using a 10 cm visual analog scale, the participants assessed global self-esteem, physical self-worth and the sub-domains of physical condition, sport competence, attractive body and physical strength (Fox & Corbin, 1989). This was conducted over three consecutive periods: in the 2 weeks before the course of injections, during the 6 weeks of injections and for 4 weeks after the injections. Aerobic capacity was assessed before and after 4 weeks of treatment. The results showed a significant increase in aerobic physical fitness in the rHuEPO group and a significant increase in perceived physical condition and physical strength scores at the end of treatment. The main psychological result was that endurance athletes were highly sensitive to the effects of rHuEPO on physical fitness. The perception of increased physical condition may lead to a stronger commitment to training. The rHuEPO injections presented a dangerous hedonic effect linked to endurance training. These results confirm the need to tackle rHuEPO abuse at any time during the training season.

Adult↗

Levels of physical activity and inactivity in children and adults in the United States: current evidence and research issues.

PURPOSE: The purpose was to describe current levels of physical activity and inactivity among adults and young people in the United States. METHODS: Estimates of participation in regular physical activity were derived from three national surveys for adults (National Health Interview Survey, National Health and Nutrition Examination Survey, and the Behavioral Risk Factor Surveillance System) and from the Youth Risk Behavior Survey for high school students. RESULTS: Overall, 63.8% of high school students surveyed on the 1997 YRBS reported participating in vigorous physical activity for at least 20 min on 3 or more days per week. Participation in vigorous activity was higher for boys (72.3%) than girls (53.5%), whites (66.8%) compared with blacks (53.9%) and Hispanics (60.4%), and decreased with advancing grade. Among adults, 27.7% meet recommended levels of either moderate or vigorous physical activity, whereas 29.2% report no regular physical activity outside of their work. Gender differences in participation in physical activity are less pronounced than in youth, and age-related patterns were complex. Whites are more active than blacks and Hispanics, and persons with higher family incomes and more education report being more physically active. There have been only minor changes in reported participation in leisure time physical activity over the past 15 yr. CONCLUSION: National estimates of physical activity appear to be reliable and valid for adults but may be less so for adolescents and are poor measures for children. Research is needed to determine the role that objective monitoring with accelerometers may play in surveillance. Reliable and valid measures of occupational, household, and transportation-related physical activity and sedentary behaviors are needed to better characterize the range of activity that is associated with health.

Adult↗