Gender,age, and sport differences in relative age effects among US Masters swimming and track and field athletes

Abstract

The aim of the present study was to examine elbow joint extension power-load characteristics with and without a countermovement. Eight male participants performed maximal elbow extensions with and without a countermovement against different loads (0, 2.5, 5.0, 7.5, 10.0, 12.5, and 15.0 kg). Electromyographic activity of the lateral and long heads of the triceps brachii and the biceps brachii muscles was recorded. The average joint power in the concentric phase was significantly enhanced in the countermovement condition at all loads except for 0 kg. The optimal load for the maximal joint power was greater in the countermovement (7.5 kg) than in the no countermovement condition (5.0 kg). Electromyographic activity was unchanged over the intensities and conditions. Our results suggest that the optimal load for the maximal joint power depends on the type of action (i.e. with or without a counter-movement), and that the enhanced joint power in the countermovement condition is due primarily to the storage and utilization of elastic energy.     

Examining relative age effects on performance achievement and participation rates in Masters athletes

Abstract

Although the relative age effect has been widely observed in youth sports (Musch & Grondin, 2001 Musch, J. and Grondin, S. 2001. Unequal competition as an impediment to personal development: A review of the relative age effect in sport. Developmental Review, 21: 147–167. [Crossref], [Web of Science ®] , [Google Scholar]), it is unclear whether it generalizes across the lifespan. The purpose of this study was to examine the relative age effect among a population of Masters athletes using archived data. Two successive studies examined the frequency of record-setting achievements (Study 1) and the frequency of participation entries (Study 2) at the US Masters track-and-field and swimming championships as a function of an individual's constituent year within any 5-year age category. Results of Study 1 indicated that the probability of setting a record increased if Masters athletes were in the first year, and decreased if they were in the third, fourth or fifth year, of an age category. Results of Study 2 indicated that the likelihood of participating in the National championships increased if Masters athletes were in the first or second year, and decreased if they were in the fourth or fifth year, of an age category. We highlight and discuss potential advantages afforded to Masters athletes who are relatively younger than their peers in the same 5-year age category.     

Trends in No Leisure-Time Physical Activity—United States, 1988–2010

Purpose: The aim of this study was to examine trends in the prevalence of no leisure-time physical activity (LTPA) from 1988 to 2010. Method: Using the Behavioral Risk Factor Surveillance System data, 35 states and the District of Columbia reported information on no LTPA from 1988 to 1994; all states reported no LTPA from 1996 to 2010. Results: No LTPA significantly declined over two decades. Prevalence for all states declined on an average of 0.6% per year from 29.1% in 1996 to 24.1% in 2004 and stabilized from 2005 to 2010, ranging from 24.0% to 25.4%. Prevalence declined for both sexes and all racial/ethnic groups. Conclusion: While the no LTPA trends improved over two decades, one in four U.S. adults still report they do not engage in LTPA.     

Learning commons: Bridging the academic and student affairs divide to enhance learning across campus

The University of Guelph Learning Commons brings student affairs professionals and librarians together to offer students a coherent and integrated approach to learning, writing, research, and technology support. It is distinguished by three characteristics: (1) a partnership model between academic and student affairs; (2) a solid foundation of theoretical perspectives to guide program development; and (3) a conceptual model to frame services. These characteristics have placed the Learning Commons in a position to play a leadership role in facilitating and enhancing learning across the university. This article describes the Learning Commons, as well as the theoretical perspectives and conceptual framework upon which the programs and services are based.