Shannon R. Siegel

Age at menarche in competitive figure skaters: variation by competency and discipline

We estimated age at menarche in a cross-sectional sample of 159 competitive figure skaters aged 11-22 years. The sample represented three standards (test stream, pre-elite, elite) and three disciplines (free skaters, pair skaters, dancers). The status quo (yes/no) and retrospective methods were used. Estimated age at menarche based on probit analysis of the status quo data was 14.2 - 0.5 years, with 95% confidence intervals of 13.2 to 15.2 years. Mean recalled age at menarche for 67 skaters aged 16 years or over was 13.6 - 1.2 years. Comparisons of skaters by standard and discipline were limited to skaters S 16 years. Menarche was, on average, significantly later ( P ≪ 0.01) in elite ( n = 36; 14.0 - 1.4 years) than in test stream ( n = 15; 12.9 - 0.8 years) skaters. Age at menarche in pre-elite skaters ( n = 16; 13.5 - 0.9 years) did not differ significantly from the other two groups. By discipline, menarche was, on average, significantly later ( P ≪ 0.01) in pair skaters ( n = 12; 14.5 - 1.3 years) than in both free skaters ( n = 38; 13.4 - 1.0 years) and dancers ( n = 17; 13.4 - 1.4 years). Early maturing girls (menarche ≪ 12.0 years; n = 2) were not represented in this sample of competitive figure skaters. Mean recalled age at menarche of mothers of skaters ( n = 84) was 13.7 - 1.3 years and the mother-daughter correlation ( n = 56 pairs) was 0.45 ( P ≪ 0.01). Later maturation was thus characteristic of competitive figure skaters, particularly in elite and more specialized pair skaters, and there was a significant familial resemblance.

Correlates of physical activity and inactivity in urban Mexican youth.

To evaluate correlates of physical activity in Mexico City school youth.

Measurement of Energy Expenditure while Playing Exergames at a Selfselected Intensity

Exergames have been suggested as a possible alternative to traditional exercise in the general population. The purpose of this study was to examine the heart rate (HR) and energy expenditure (EE) of young adults playing several different exergames, while self-selecting the component of the game to play and the intensity. A total of 117 participants, 18-35 years of age, were evaluated on one of four active video games. Participants were free to choose any component of the given game to play and they played at a self-selected intensity. The average HR and EE during the individual games were compared to resting conditions and to the American College of Sports Medicine (ACSM) guidelines. The HR and EE increased above resting conditions during each game (p<0.05). When the results of all games were combined, the HR was 125.4 ± 20.0 bpm and the average EE was 6.7 ± 2.1 kcal/min. This HR represents an average percent of heart rate reserve of 44.6 ± 14.1, high enough to be considered moderate intensity exercise. If performed for 30 minutes a day, five days per week, the average EE would be 1,005 kcals, enough to meet the ACSM recommendations for weekly EE. Therefore, at least some exergames could be a component of an exercise program.

Secular trends in established and novel cardiovascular risk factors in Welsh 12-13 year olds: A comparison between 2002 and 2007

Background: This study examines CVD risk factors trends in Welsh adolescents between 2002 and 2007. Participants and methods: CVD risk factor data was examined from two cross-sectional studies. The first study (73 participants; aged 12.9 ± 0.3 years) was completed in 2002. The second study (90 participants; aged 12.9 ± 0.4 years) was conducted in 2007. Measurements included body mass index (BMI), waist circumference (WC), total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglyceride, fibrinogen (Fg) and high-sensitivity C-reactive protein (hs-CRP). Results: In boys, mean BMI and WC were lower in 2007, although not significantly (p ≥ 0.05). In 2007, there were improvements in mean lipid, Fg and hs-CRP concentrations in both sexes (p < 0.05). In 2002, 42.8% of boys and 34.2% of girls were overweight or obese; in 2007, this was 23.7% and 28.9% for boys and girls, respectively. More adolescents in 2002 exceeded the recommended levels for lipids, Fg and hs-CRP. Conclusion: This is the only study to examine CVD risk factor trends in Welsh adolescents. Although overweight continues to be widespread in 12-13 year olds, this study did not identify significant mean changes in overweight and obesity between 2002 and 2007. Overall, the data presented a positive trend in lipid profile and inflammatory factors.

Participation in organized sport among urban mexican youth

Na medida em que todas as obras da UC Digitalis se encontram protegidas pelo Código do Direito de Autor e Direitos Conexos e demais legislação aplicável, toda a cópia, parcial ou total, deste documento, nos casos em que é legalmente admitida, deverá conter ou fazer-se acompanhar por este aviso. Participation in organized sport among urban mexican youth Autor(es): Siegel, Shannon R.; Peña Reyes, Maria e; Cárdenas Barahona, Eyra e; Malina, Robert M. Publicado por: Imprensa da Universidade de Coimbra URL persistente: URI:http://hdl.handle.net/10316.2/38866 DOI: DOI:http://dx.doi.org/10.14195/978-989-26-1171-6_3

Estimated physical activity and inactivity in urban mexican school youth

The purpose of this study is to compare estimates of physical activity and physical inactivity in urban Mexican school youth. A cross-sectional survey was conducted with 1085 school youth (525 males, 560 females), 9-18 years of age resident in Mexico City. Socioeconomic status (SES) was estimated. The Physical Activity Questionnaire (PAQ) was used to estimate activity over the past week. Television and video game time were noted. Height and weight were measured; the BMI was calculated. Youth were classified as normal weight, overweight or obese using international criteria. MANOVA was used to compare physical activity and inactivity by SES, age group (9-10, 11-13, and 14-18 years) within and between sexes, and by weight status. The most common non-sport physical activities are walking and jogging in girls and jogging, walking and bicycling in boys. Frequent (≥3 times per week) participation in sport activities is more common among boys than girls. Within each age group and sex, PAQ scores and screen time do not differ by SES, and boys are more physically active than girls. Boys spend more time playing video games than girls at all ages. Younger males and females have higher activity scores than the oldest group. Correlations between the BMI and the PAQ score are low. Estimated physical activity and screen time do not differ among youth by weight status. The majority of urban Mexican youth in this sample had insufficient physical activity and seemingly too much inactivity, both of which have negative implications on health status.