Power output of field-based downhill mountain biking

The purpose of this study was to assess the power output of field-based downhill mountain biking. Seventeen trained male downhill cyclists (age 27.1 +/- 5.1 years) competing nationally performed two timed runs of a measured downhill course. An SRM powermeter was used to simultaneously record power, cadence, and speed. Values were sampled at 1-s intervals. Heart rates were recorded at 5-s intervals using a Polar S710 heart rate monitor. Peak and mean power output were 834 +/- 129 W and 75 +/- 26 W respectively. Mean power accounted for only 9% of peak values. Paradoxically, mean heart rate was 168 +/- 9 beats x min(-1) (89% of age-predicted maximum heart rate). Mean cadence (27 +/- 5 rev x min(-1)) was significantly related to speed (r = 0.51; P < 0.01). Analysis revealed an average of 38 pedal actions per run, with average pedalling periods of 5 s. Power and cadence were not significantly related to run time or any other variable. Our results support the intermittent nature of downhill mountain biking. The poor relationships between power and run time and between cadence and run time suggest they are not essential pre-requisites to downhill mountain biking performance and indicate the importance of riding dynamics to overall performance.     

Computer use within a play-based early years curriculum

Early years curricula promote learning through play and in addition emphasise the development of computer literacy. Previous research, however, has described that teachers feel unprepared to integrate Information and Communication Technology (ICT) and play. Also, whereas research has suggested that effective computer use in the early years is associated with adult direction, further research suggests adult presence can inhibit play and reduce children's engagement. Focusing on 12 settings following the Welsh play-based Foundation Phase, this paper explores teachers' experiences of integrating computer use into classroom practice, children's levels of engagement with computer activities and how playful children perceive computer use to be. Teachers confidently delivered a variety of computing experiences. Children consistently rated these activities as play regardless of adult presence and demonstrated moderate to high levels of engagement. Findings and the features of observed practice are discussed in relation to the teachers' role as a play partner and the successful co-construction of the play-based curriculum.     

Student attitudes toward closed-circuit instructional television

Summary The objectives of this study were to examine (1) the relative effectiveness of closed-circuit television for classroom teaching compared to conventional teaching and (2) the acceptability of closed-circuit television teaching to the students. A course was offered both by closed-circuit television and by conventional teaching. Students within each group were asked to rate the course and other related concepts. In addition, their examination grades were obtained. No differences were found with respect to performance. The students taught via television rated the course and their instructors relatively lower than those who received conventional instruction. Howard M. Bobren is assistant to the director, Institute of Communications Research and Sheldon L. Siegel is research assistant, College of Education, both at the University of Illinois.