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The purpose was to assess the specificity of muscular fatigue and changes in the stretch-evoked forces and integrated surface electromyographic (EMG) activity of the vastus lateralis and biceps femoris muscles in 12 endurance and 12 power athletes. On each of four separate days, fatigue was induced with 49 repetitions of isometric, shortening, and lengthening knee extension and with 1-min continuous vertical jumping. Before and after fatigue, testing included 5-s isometric knee extension with a superimposed stretch, shortening, and lengthening knee extension. Endurance and power athletes produced significantly greater lengthening and stretch forces compared to isometric and shortening forces. Within each group, lengthening and stretch forces were not different. Isometric force was significantly greater than shortening force in power but not in endurance athletes. Power athletes averaged 57.4% stronger than endurance athletes for the three measures of knee extension strength. Power athletes produced significantly more integrated EMG during isometric, shortening, and lengthening knee extension than endurance athletes, but there were no between-group differences in the integrated EMG of the biceps femoris. Endurance athletes showed significantly less stretch-evoked force potentiation (10.4 N x 10) than power athletes (14.4 N x 10). Expressed as a percentage of isometric force, the superimposed stretch increased force production by 20% in endurance and 15% in power athletes. The integrated EMG due to the stretch increased by 37.6 and 21.7 $\mu$V$\cdot$s or 23% and 15% in power and in endurance athletes. Based on the stretch-evoked force-to-EMG ratios, endurance athletes used approximately twice as much neural drive to potentiate the same amount of force as power athletes. Endurance athletes showed significantly less force fatigue ($\sim$7%) than power athletes (26%) for isometric, shortening, and lengthening knee extension exercise. Muscular fatigue was the greatest with lengthening exercise in power but not in endurance athletes, 5 of whom increased lengthening force by the 49th repetition. Fatigue in the endurance athletes was the greatest after the 1-min vertical jumping protocol (-6.4%). The average decline in the integrated EMG of the vastus lateralis was 17% and 22% in endurance and power athletes. Stretch-evoked force did not change with fatigue, while EMG potentiation significantly declined after the four fatigue protocols in both groups. For the endurance and power athletes, there was no indication for specificity of force or EMG fatigue. Thus, the current data suggest that in two groups of athletes, muscular fatigue was general in terms of force loss and EMG activity assessed by three test modes and four fatigue protocols.

The primary purpose of this study was to further the understanding of how people learn to teach. The central research question focused on differences in teaching knowledge that may be associated with training and experience. Eight teachers were selected to participate in this study. They represented a wide range of teaching experience, formal training, professional certification and sport participation. The common criterion for selection was previous experience in the teaching of volleyball. Data were collected from both questionnaires and transcribed interviews which followed the viewing of a twenty-minute videotaped volleyball lesson. Results indicated differences among the participating teachers in content knowledge (the skills of playing volleyball), pedagogical knowledge (general teaching principles), and pedagogical content knowledge (content-specific teaching knowledge). The comments of trained teachers displayed a greater awareness of and concern for general teaching principles. In contrast, untrained teachers devoted most of their comments to lesson content. Experienced teachers, whether trained or untrained, demonstrated a superior understanding of the relationship between the nature of content and the needs of learners at different levels of skill development. In that regard, they had a more elaborately developed sense of pedagogical content knowledge. Untrained teachers cited their experience as students and athletes as major sources of information about teaching, while trained teachers pointed to experiences associated with their formal training. Members from both group indicated that they had learned from role models and early teaching experiences. Among trained and untrained teachers the sources for the differences in knowledge, and how that knowledge was processed, included the following: varied teaching contexts such as public high schools and university classes, the extent of teaching experience which ranged from one to eighteen years, and views about teaching that were influenced by previous experience in either coaching or teaching roles. Implications for teacher education and staff development include a need for training experiences that will integrate various forms of teaching knowledge. In addition, it is clear that teacher preparation programs must deal much more explicitly with the differences between coaching and teaching contexts.

The purpose of this study was to investigate the phenomenon of public school physical education teachers holding multiple jobs. Data were collected through interviews in which 17 secondary physical education teachers described their motives and perceptions concerning the combination of teaching with other forms of employment. Each teacher was interviewed twice. In the first, unstructured interview, participants were encouraged to identify what they regarded as the realities of moonlighting, the purpose being to identify questions, problems, and issues not previously encountered or understood. Prior to the second interview, participants were asked to read through an abbreviated transcript of the first interview which documented primary areas of interest and items which required amplification or exploration. Profiles developed from the participants' own words provide a description of their moonlighting experiences and the impact of multiple employment on personal and professional lives. The profiles make clear that moonlighting is a highly individual phenomenon. Nevertheless, analysis of the transcripts served to yield a number of themes which were common to most of the participants' career patterns. Three particular themes appear to be both common and powerful in the professional lives of physical education teachers: (1) dissatisfactions with teaching and conditions in the school workplace often push teachers out into second jobs, (2) certain kinds of second jobs are regarded as part of professional responsibility, (3) some teachers spend more time in second jobs because limited time commitments in their personal lives leave a surplus of uncommitted time. For some teachers moonlighting simply is an economic necessity. Gender, marital status and age-related life cycle factors all serve to shape the importance of supplementing teaching income through additional employment. Finally, teachers hold mixed views concerning the impact of holding second jobs on their ability to function effectively in the school.