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Jorge Mota, Nuno Delgado, Mariana Almeida, José Carlos Ribeiro and Maria Paula Santos

Background:

The purpose of this study was 1) to compare physical activity levels according to body-mass index; 2) to determine which, if any, neighborhood perceived attributes were related to overweight.

Methods:

The sample comprised 610 girls age 14.7 ± 1.6 y. Girls were grouped into normal weight and overweight. Environmental variables and physical activity were assessed by questionnaire.

Results:

No significant differences were found in physical activity levels between normal weight and overweight girls. Logistic regression analysis revealed that girls who agreed that “there is so much traffic on the streets that it makes it unpleasant to walk in the neighborhood” were more likely to be overweight (OR = 1.78; 95% CI 1.10 to 2.89).

Conclusion:

The study found no relationship between perceptions of the environment and overweight among Portuguese girls, except for perceptions of security for walking in the neighborhood.

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Jorge Mota, Pedro Silva, Luísa Aires, Maria Paula Santos, José Oliveira and José C. Ribeiro

Background:

The purpose of this study was to examine whether there are differences in physical activity (PA) during specific periods of the day among active and less-active girls.

Methods:

The sample comprised 54 girls age 10 to 15 years. PA was assessed by accelerometry. Girls were grouped as less active, active, and highly active.

Results:

Total minutes of moderate-to-vigorous physical activity (MVPA) was significantly higher in more-active girls than in their less-active peers (113 and 72 min/d, respectively). The most-active groups were significantly more engaged in MVPA during the outside-of-school period than were less-active girls. Highly active girls spent a significantly higher amount of their MVPA time outside of school than did the less-active group, which spent a significantly higher proportion of MVPA time during late afternoon.

Conclusion:

Outside-of-school PA is a key point for MVPA engagement. Particularly for the less-active girls, however, schools might provide additional PA.

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Sofiya Alhassan and Thomas N. Robinson

Background:

Receiver operating characteristic (ROC) analysis is a common method used in diagnostic and screening tests to define thresholds levels of a factor that discriminates between 2 levels of another factor. The purpose of this analysis was to use ROC analysis to determine the optimal accelerometer-measured physical activity (PA) thresholds for predicting selective cardiovascular disease (CVD) risk factors.

Methods:

ROC was performed using data from Stanford Girls Health Enrichment Multisite Studies trial. PA was assessed for multiple days using accelerometers. CVD variables were overweight, elevated triglyceride, reduced HDL-C, hypertension, impaired fasting glucose, fasting insulin, and clustering of multiple CVD risk factors.

Results:

A sample of 261 girls participated, of which 208 had complete CVD risk measures (mean ± SD age = 9.4 ± 0.9yrs, BMI = 20.7 ± 4.8kg/m2). An average of ≥11.1 minutes/day at ≥2,600 counts/min was the maximally sensitive and specific threshold for discriminating girls who were overweight, ≥16.6 minutes/day at ≥2,000 counts/min for hyperinsulinemia or with ≥2 CVD risk factors. The Area Under the Curve for overweight, hyperinsulinemia, and ≥2 CVD risk factors was of 0.66, 0.58, and 0.60, respectively. The sensitivity and specificity associated with overweight, hyperinsulinemia, and ≥2 CVD risk factors were 60.3% and 72.9%, 53.3% and 83.9%, 44.0% and 84.7%, respectively.

Conclusion:

Empirically-derived thresholds of PA to optimally discriminate between girls with and without CVD risk were lower in this sample than generally recommended. This ROC approach should be repeated in other populations to determine optimal PA thresholds with clinical validity for research, surveillance and program evaluation.

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Phillip Post and Rebecca Palacios

United States are not meeting the recommended 60 min of daily MVPA, girls are at a greater risk of being inactive than boys. Girls are consistently less active than boys regardless of their race, income status, weight, or age ( Belcher et al., 2010 ; Troiano et al., 2008 ). Only about 35% of girls aged

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Sofiya Alhassan, John R. Sirard, Tirzah R. Spencer, Ann Varady and Thomas N. Robinson

Background:

The purpose of this study was to develop a data-driven approach for analyzing incomplete accelerometer data from field-base studies.

Methods:

Multiple days of accelerometer data from the Stanford Girls health Enrichment Multi-site Studies (N = 294 African American girls) were summed across each minute of each day to produce a composite weekday and weekend day. Composite method estimates of physical activity were compared with those derived from methods typically described in the literature (comparison methods).

Results:

The composite method retained 99.7% and 100% of participants in weekday and weekend-day analysis, respectively, versus 84.7% to 94.2% and 28.6% to 99.0% for the comparison methods. Average wearing times for the composite method for weekday and weekend day were 99.6% and 98.6%, respectively, 91.7% to 93.9% and 82.3% to 95.4% for the comparison methods. Composite-method physical activity estimates were similar to comparison-methods estimates.

Conclusion:

The composite method used more available accelerometer data than standard approaches, reducing the need to exclude periods within a day, entire days, and participants from analysis.

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Olivier Hue, Sophie Antoine-Jonville, Olivier Galy and Stephen Blonc

The authors investigated the anthropometric and physiological characteristics of young Guadeloupian competitive swimmers in relation to swimming performance and compared the abilities of these children with those of the young white swimmers reported in the literature. All 2004 competitive swimmers between 10 and 14 y old (126 children, 61 boys and 65 girls, 12.0 ± 1.3 y) from Guadeloupe underwent anthropometric measurements and physiological and performance testing. Six boys on the French national swimming team are referred to hereafter as the 2011 elite subgroup. Anthropometric parameters, a jump-and-reach test, glide, and estimated aerobic power (eVO2max) were assessed in terms of swimming-performance analysis through a 400-m test. This study demonstrated that the Guadeloupian swimmers had more body fat than most age-matched white swimmers but had very poor hydrostatic lift; they had higher peak jump height and they swam as well as their white counterparts. The variability in 400-m performance between subjects was best described by glide, age, and eVO2max. Compared with the group of boys with the same age, the 2011 elite subgroup was significantly better for arm span, peak jump height, glide, and 400-m and 15-m performances. Further research is needed to investigate motor organization and energy cost of swimming in Afro-Caribbean swimmers.

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Shara Crookston

Studies that cite the positive outcomes of girls participating in sports are well documented ( Janssen & Leblac, 2010 ; Women’s Sports Foundation, 2016 ) and include girls reporting higher levels of confidence and self-esteem and lower levels of depression. Girls who play sports are less likely to

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Maureen R. Weiss, Lindsay E. Kipp, Alison Phillips Reichter, Sarah M. Espinoza and Nicole D. Bolter

This manuscript introduces our comprehensive project evaluating the effectiveness of Girls on the Run , a physical activity-based youth development program. Considerable evidence reveals the many health benefits of regular physical activity for children and youth, including cardiorespiratory

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Lennart Raudsepp and Kristi Vink

participation is at its highest level, especially in girls. 9 In a recent longitudinal study, Trilk et al 10 found that the number of sedentary minutes per day increased approximately 11% from sixth to eighth grade across different sedentary behaviors. According to behavioral economic theory 11 and findings

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Stephen Heung-Sang Wong and Feng-Hua Sun

The purpose of the current study was to examine the effect of flavor on voluntary drinking and thermoregulatory responses in Chinese boys and girls exercising intermittently in a hot environment. Fourteen boys and girls (9 to 11 years old) performed four 3-hour intermittent exercise sessions (20-min walking sessions at 50% VO2peak followed by a 25-minute rest period) in a hot and humid environment (~30 °C ambient temperature and ~70% relative humidity). The participants consumed 1 of 4 beverages ad libitum in a randomized sequence by using a Latin-square principle: unflavored water (W), orange-flavored water (OF), lemon-flavored water (LF), and grape-flavored water (GF). No differences were observed in the total fluid intake (W vs. OF vs. LF vs. GF: Boys, 441 ± 114 vs. 493 ± 106 vs. 387 ± 83 vs. 568 ± 146 ml; Girls, 613 ± 131 vs. 923 ± 204 vs. 825 ± 157 vs. 790 ± 166 ml), urine and sweat output, and physiological perceptual variables among trials and between sexes. The results suggested that Chinese children can maintain body fluid balance while exercising moderately in a hot and humid environment by ad libitum drinking. The flavor of the beverages had no impact on the voluntary drinking and the state of hydration in the current study.