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Jenny Meggs, Mark Chen and Danielle Mounfield

Research has identified a correlation between prenatal markers of testosterone (2D4D) and sport performance. This relationship is thought to be explained by several important psychophysiological variables such as physical fitness and mental toughness. The current study sought to add to this body of research by examining the differences between high and low 2D4D, in measures of gender identity (Bem Sex Role Inventory) and mental toughness (the 48-item version of the Mental Toughness Questionnaire). A sample of 116 recreational (n = 59) and competitive netballers (n = 57) completed the psychological measures and provided right-hand scans from which 2D4D ratio measures were drawn. The key results included a large effect of low digit ratio on emotional control, life control, and interpersonal confidence. These findings suggest that 2D4D could provide a marker for sporting potential and mental toughness in female sport participants. However, future research may wish to establish the relative contribution of prenatal factors (e.g., 2D4D) and socialization factors (e.g., involvement in a sporting context) on sporting ability and related psychological variables.

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David J. Blakelock, Mark A. Chen and Tim Prescott

Elite adolescent soccer players may represent one athletic population that is vulnerable to developing psychological distress following deselection. This study examined the proportion of players experiencing clinical levels of psychological distress following selection procedures and whether player status (i.e., deselected vs. retained) had a significant effect on psychological distress. Data was collected from 91 players who completed the General Health Questionnaire -12 at three time points: 7–14 days before selection procedures, 7 days after and 21 days after. Although outcomes were heterogeneous, a sizable proportion of deselected players were found to experience clinical levels of psychological distress. A factorial ANOVA (p < .001) found that deselected players experienced higher levels of psychological distress than retained players at postselection time points. The research provides evidence that some deselected players are “at risk” of developing clinical levels of psychological distress. Clinical implications and recommendations for future research are discussed.

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J. Mark Davis, Catherine J. Carlstedt, Stephen Chen, Martin D. Carmichael and E. Angela Murphy

Quercetin, a natural polyphenolic flavonoid substance present in a variety of food plants, has been shown in vitro and in animal studies to have widespread health and performance benefits resulting from a combination of biological properties, including antioxidant and anti-inflammatory activity, as well as the ability to increase mitochondrial biogenesis. Little is known about these effects in humans, however, especially with respect to exercise performance. The authors determined whether quercetin ingestion would enhance maximal aerobic capacity and delay fatigue during prolonged exercise in healthy but untrained participants. Twelve volunteers were randomly assigned to 1 of 2 treatments: (a) 500 mg of quercetin twice daily dissolved in vitamin-enriched Tang or (b) a nondistinguishable placebo (Tang). Baseline VO2max and bike-ride times to fatigue were established. Treatments were administered for a period of 7 days using a randomized, double-blind, placebo-controlled, crossover study design. After treatment both VO2max and ride time to fatigue were determined. Seven days of quercetin feedings were associated with a modest increase in VO2max (3.9% vs. placebo; p < .05) along with a substantial (13.2%) increase in ride time to fatigue (p < .05). These data suggest that as little as 7 days of quercetin supplementation can increase endurance without exercise training in untrained participants. These benefits of quercetin may have important implications for enhancement of athletic and military performance. This apparent increase in fitness without exercise training may have implications beyond that of performance enhancement to health promotion and disease prevention.

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Salomé Aubert, Joel D. Barnes, Nicolas Aguilar-Farias, Greet Cardon, Chen-Kang Chang, Christine Delisle Nyström, Yolanda Demetriou, Lowri Edwards, Arunas Emeljanovas, Aleš Gába, Wendy Y. Huang, Izzeldin A.E. Ibrahim, Jaak Jürimäe, Peter T. Katzmarzyk, Agata Korcz, Yeon Soo Kim, Eun-Young Lee, Marie Löf, Tom Loney, Shawnda A. Morrison, Jorge Mota, John J. Reilly, Blanca Roman-Viñas, Natasha Schranz, John Scriven, Jan Seghers, Thomas Skovgaard, Melody Smith, Martyn Standage, Gregor Starc, Gareth Stratton, Tim Takken, Tuija Tammelin, Chiaki Tanaka, David Thivel, Richard Tyler, Alun Williams, Stephen H.S. Wong, Paweł Zembura and Mark S. Tremblay

Background: To better understand the childhood physical inactivity crisis, Report Cards on physical activity of children and youth were prepared concurrently in 30 very high Human Development Index countries. The aim of this article was to present, describe, and compare the findings from these Report Cards. Methods: The Report Cards were developed using a harmonized process for data gathering, assessing, and assigning grades to 10 common physical activity indicators. Descriptive statistics were calculated after converting letter grades to interval variables, and correlational analyses between the 10 common indicators were performed using Spearman’s rank correlation coefficients. Results: A matrix of 300 grades was obtained with substantial variations within and between countries. Low grades were observed for behavioral indicators, and higher grades were observed for sources of influence indicators, indicating a disconnect between supports and desired behaviors. Conclusion: This analysis summarizes the level and context of the physical activity of children and youth among very high Human Development Index countries, and provides additional evidence that the situation regarding physical activity in children and youth is very concerning. Unless a major shift to a more active lifestyle happens soon, a high rate of noncommunicable diseases can be anticipated when this generation of children reaches adulthood.

Open access

Salomé Aubert, Joel D. Barnes, Chalchisa Abdeta, Patrick Abi Nader, Ade F. Adeniyi, Nicolas Aguilar-Farias, Dolores S. Andrade Tenesaca, Jasmin Bhawra, Javier Brazo-Sayavera, Greet Cardon, Chen-Kang Chang, Christine Delisle Nyström, Yolanda Demetriou, Catherine E. Draper, Lowri Edwards, Arunas Emeljanovas, Aleš Gába, Karla I. Galaviz, Silvia A. González, Marianella Herrera-Cuenca, Wendy Y. Huang, Izzeldin A.E. Ibrahim, Jaak Jürimäe, Katariina Kämppi, Tarun R. Katapally, Piyawat Katewongsa, Peter T. Katzmarzyk, Asaduzzaman Khan, Agata Korcz, Yeon Soo Kim, Estelle Lambert, Eun-Young Lee, Marie Löf, Tom Loney, Juan López-Taylor, Yang Liu, Daga Makaza, Taru Manyanga, Bilyana Mileva, Shawnda A. Morrison, Jorge Mota, Vida K. Nyawornota, Reginald Ocansey, John J. Reilly, Blanca Roman-Viñas, Diego Augusto Santos Silva, Pairoj Saonuam, John Scriven, Jan Seghers, Natasha Schranz, Thomas Skovgaard, Melody Smith, Martyn Standage, Gregor Starc, Gareth Stratton, Narayan Subedi, Tim Takken, Tuija Tammelin, Chiaki Tanaka, David Thivel, Dawn Tladi, Richard Tyler, Riaz Uddin, Alun Williams, Stephen H.S. Wong, Ching-Lin Wu, Paweł Zembura and Mark S. Tremblay

Background: Accumulating sufficient moderate to vigorous physical activity is recognized as a key determinant of physical, physiological, developmental, mental, cognitive, and social health among children and youth (aged 5–17 y). The Global Matrix 3.0 of Report Card grades on physical activity was developed to achieve a better understanding of the global variation in child and youth physical activity and associated supports. Methods: Work groups from 49 countries followed harmonized procedures to develop their Report Cards by grading 10 common indicators using the best available data. The participating countries were divided into 3 categories using the United Nations’ human development index (HDI) classification (low or medium, high, and very high HDI). Results: A total of 490 grades, including 369 letter grades and 121 incomplete grades, were assigned by the 49 work groups. Overall, an average grade of “C-,” “D+,” and “C-” was obtained for the low and medium HDI countries, high HDI countries, and very high HDI countries, respectively. Conclusions: The present study provides rich new evidence showing that the situation regarding the physical activity of children and youth is a concern worldwide. Strategic public investments to implement effective interventions to increase physical activity opportunities are needed.