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31.
Cardiorespiratory fitness affords health benefits to youth. Among females, weight-relative fitness declines during puberty and is lower among African American (AA) than Caucasian girls. Data indicate racial differences in pubertal timing and tempo, yet the interactive influence of puberty and race on fitness, and the role of physical activity (PA) in these associations have not been examined. Thus, independent and interactive associations of race and pubertal development with fitness in adolescent girls, controlling for PA were examined. Girls in grades 5–8 (n = 1011; Caucasian = 25.2%, AA = 52.3%, Other Race group = 22.5%) completed the Pubertal Development Scale (pubertal stage assessment) and Fitnessgram® Progressive Aerobic Cardiovascular Endurance Run (PACER) test (cardiorespiratory fitness assessment). PA was assessed by accelerometry. Bivariate and multivariate analyses were used to examine associations among race, pubertal stage and fitness, controlling for vigorous PA, AA, and pubertally advanced girls demonstrated lower fitness than Caucasian and less mature counterparts. Puberty and race remained significantly associated with fitness after controlling for vigorous PA. The interaction effect of race and puberty on fitness was non-significant. The pubertal influence on fitness is observed among AA adolescents. Associations between fitness and race/puberty appear to be independent of each other and vigorous PA. Pubertally advanced AA girls represent a priority group for fitness interventions.  相似文献   
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The relationship between average daily step counts and age, body mass index (BMI), self-reported physical activity (PA) level, and perceived health was determined in 85 middle-aged and older adults who wore a pedometer for 7 consecutive days. Average daily steps were significantly (p < .05) correlated with BMI (r = -.26), age (r = -.44) and perceived health (r = .53) but not with self-reported PA level (r = .19). The adjusted percentage of participants classified as meeting the PA recommendation in < or = 5,000, 5,001-9,999, and > or = 10,000 steps/day categories ranged from 53 to 61%. These findings support previous evidence in younger populations suggesting that the recommended minimal level of health-related PA may be achieved despite not accumulating 10,000 steps/day.  相似文献   
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ABSTRACT

This study developed and evaluated machine learning algorithms to predict children’s physical activity category from raw accelerometer data collected at the hip. Fifty participants (mean age = 13.9 ± 3.0 y) completed 12 activity trials that were categorized into 5 categories: sedentary (SED), light household activities and games (LHHAG), moderate-vigorous games and sports (MVGS), walking (WALK), and running (RUN). Random Forest (RF) and Logistic Regression (LR) classifiers were trained with features extracted from the vector magnitude using 10?s non-overlapping windows. Classification accuracy was evaluated using leave-one-subject-out cross validation. Overall accuracy for the RF and LR classifiers was 95.7% and 94.3%, respectively. Classification accuracy was excellent for SED (96.3% – 98.1%), LHHAG (92.3% – 95.2%), WALK (94.5% – 97.1%), RUN (99.5% – 99.6%); and MVGS (87.5% – 92.7%). The results indicate that classifiers trained on features in the raw acceleration from the hip can be used for activity recognition in young people.

Abbreviations: VM: Vector Magnitude; RF: Random Forest; LR: Logistic Regression; LOSO: Leave-One-Subject-Out  相似文献   
35.
Chronic illnesses and disabilities may impair the attainment of age-typical developmental tasks, such as forming relationships with peers and gaining autonomy. Based on a systematic search in electronic databases and cross-referencing, 447 quantitative empirical studies were included which compared the attainment of developmental tasks of adolescents with and without chronic physical illness or physical/sensory disability. Adolescents with chronic illness or disability had more problems than healthy/nondisabled peers with regard to autonomy, body acceptance, developing friendships and romantic relationships, gaining access to a peer-group, career preparation, preparing for family life and developing socially responsible behaviour. However, between-group differences were small. No between-group differences were found regarding gender role acquisition and identity development. Success in solving developmental tasks varied, in part, by disease group, visibility of the disease/disability, age, gender and representativeness of the sample. Interventions aimed at promoting the attainment of developmental tasks are recommended.  相似文献   
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The present study compared psychological adjustment of 158 adolescents with vision impairment and 158 sighted adolescents with a matched-pair design using the Strengths and Difficulties Questionnaire. Adolescent self-reports and teacher reports on emotional problems, peer problems, and total difficulties showed higher scores in students with vision impairment than in sighted students. However, the size of between-group differences was small, and adolescents who are blind and their peers with low vision showed similar levels of psychological adjustment. In addition, older students reported more emotional problems than younger students. Furthermore, differences between self-reported emotional problems of students with and without vision impairment were stronger in older participants. In both groups, girls showed more emotional problems and less conduct problems than boys. We conclude that most students with vision impairment are well adjusted but a minority may benefit from psychological interventions.  相似文献   
38.
The present study analyzed whether the perceived attainment of developmental goals differs by school type and between adolescents with visual impairments and sighted peers. We created a matched-pair design with 98 German students from the middle school track and 98 from the highest school track; half of the members of each group were visually impaired. Students from the middle school track reported a higher attainment of identity development, career choice, and gender role awareness than students from the highest school track. Furthermore, students with visual impairment were less progressed with peer-group integration and forming intimate relationships than sighted students, but they reported higher levels of attainment of skills that are important for their future profession. However, we did not find an overall interaction effect between school type and vision status on the perceived attainment of developmental goals. The observed school type differences can be explained by the fact that students from the middle school track face the transition from school to work earlier. Implications for practice are discussed.  相似文献   
39.
This study examined the internal consistency and validity of a new rating scale to identify gifted students, the Gifted Rating Scales-School Form (GRS-S). The study explored the effect of gender, race/ethnicity, age, and rater familiarity on GRS-S ratings. One hundred twenty-two students in first to eighth grade from elementary and middle schools in the southeastern United States participated in the investigation. Results indicated high internal consistency for the six GRS-S scales: Intellectual Ability, Academic Ability, Creativity, Artistic Talent, Leadership, and Motivation. Results revealed no effect of race/ethnicity, age, or rater familiarity with the student. There was no significant effect for gender, although a trend was noted for girls rated slightly higher than boys across all scales. This trend was consistent with analyses of the standardization data and with cross-cultural findings using translated versions of the GRS-S. The present findings provided support for the GRS-S as a valid gifted screening instrument.  相似文献   
40.
ABSTRACT

Purpose: Maximal heart rate (MHR) is an important physiologic tool for prescribing and monitoring exercise in both clinical and athletic settings. However, prediction equations developed in adults may have limited accuracy in youth. The purpose of this study was to systematically review and analyze the available evidence regarding the validity of commonly used age-based MHR prediction equations among children and adolescents. Methods: Included articles were peer-reviewed, published in English, and compared measured to predicted MHR in male and female participants <18 years old. The standardized mean difference effect size (ES) was used to quantify the accuracy of age-predicted MHR values and a priori moderators were examined to identify potential sources of variability. Results: The cumulative results of 20 effects obtained from seven articles revealed that prediction equations did not accurately estimate MHR (ES= 0.44, p < .05) by 6.3 bpm (bpm). Subgroup analyses indicated that the Fox equation (MHR = 220–age) overestimated MHR by 12.4 bpm (ES = 0.95, p < .05), whereas the Tanaka equation (MHR = 208–0.7*age) underestimated MHR by 2.7 bpm (ES = ?0.34, p < .05). Conclusions: Age-based MHR equations derived from adult populations are not applicable to children. However, if the use of age-based equations cannot be avoided, we recommend using the Tanaka equation, keeping in mind the range of error reported in this study. Future research should control for potential pubertal influences on sympathetic modulation during exercise to facilitate the development of more age-appropriate methods for prescribing exercise intensity.  相似文献   
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