‘A tribute to Dr J. Rogge’ aims to systematically review muscle activity and muscle fatigue during sustained submaximal quasi-isometric knee extension exercise (hiking) related to Olympic dinghy sailing as a tribute to Dr Rogge’s merits in the world of sports. Dr Jacques Rogge is not only the former President of the International Olympic Committee, he was also an orthopaedic surgeon and a keen sailor, competing at three Olympic Games. In 1972, in fulfilment of the requirements for the degree of Master in Sports Medicine, he was the first who studied a sailors’ muscle activity by means of invasive needle electromyography (EMG) during a specific sailing technique (hiking) on a self-constructed sailing ergometer. Hiking is a bilateral and multi-joint submaximal quasi-isometric movement which dinghy sailors use to optimize boat speed and to prevent the boat from capsizing. Large stresses are generated in the anterior muscles that cross the knee and hip joint, mainly employing the quadriceps at an intensity of 30–40% maximal voluntary contraction (MVC), sometimes exceeding 100% MVC. Better sailing level is partially determined by a lower rate of neuromuscular fatigue during hiking and for ≈60% predicted by a higher maximal isometric quadriceps strength. Although useful in exercise testing, prediction of hiking endurance capacity based on the changes in surface EMG in thigh and trunk muscles during a hiking maintenance task is not reliable. This could probably be explained by the varying exercise intensity and joint angles, and the great number of muscles and joints involved in hiking.Highlights
Dr Jacques Rogge, former president of the International Olympic Committee and Olympic Finn sailor, was the first to study muscle activity during sailing using invasive needle EMG to obtain his Master degree in Sports Medicine at the Ghent University.
Hiking is a critical bilateral and multi-joint movement during dinghy racing, accounting for >60% of the total upwind leg time. Hiking generates large stresses in the anterior muscles that cross the knee and hip joint.
Hiking is considered as a quasi-isometric bilateral knee extension exercise. Muscle activity measurements during sailing, recorded by means of EMG, show a mean contraction intensity of 30-40% maximal voluntary contraction with peaks exceeding 100%.
Hiking performance is strongly related to the development of neuromuscular fatigue in the quadriceps muscle. Since maximal strength is an important determinant of neuromuscular fatigue during hiking, combined strength and endurance training should be incorporated in the training program of dinghy sailors.
The majority of unserved and underserved handicapped children live in rural America (Sher, 1978). One obstacle to serving these children is a lack of qualified staff (Helge, 1981). The turnover rates for rural and urban school psychologists in Virginia were determined for the years 1977–78 through 1979–80: the rate for rurai school psychologists is four times the rate for urban school psychologists (p<.001). Rural school psychologists who terminated employment and rural school psychologists who remained were surveyed on selected background variables in 1981. School psychologists who remained were much more likely than those who left to have been raised in a nonurban community. Implications for training programs are discussed. 相似文献
Results of two case studies in which parents served as cotherapists in a social cognitive problem-solving program are presented. Larry, nine years old, was referred due to distractibility, immaturity, and impulsivity. Robert, eight years old, was referred for aggressive behaviors. Training occurred once a week for 50 minutes for 17 weeks for Larry and for 15 weeks for Robert. Parents were included in training in an effort to promote generalization and transfer of training outcomes. The parents' role included cognitive modeling, reinforcing, providing problem situations from the prior week, and extending training through generalization tasks at home. The following dependent measures were obtained in a pre-post design: Conners Teacher and Parent Rating Scales, Sociometric measures, WISC-R Mazes and Block Design, tests of consequential and means-end thinking, and observations of task-relevant and irrelevant self-verbalizations during Mazes and Block Design: Treatment effects were found for both boys on the parent and teacher versions of the Conners questionnaire. Larry improved in task relevant self-verbalizations, Mazes performance, and consequential and means-end thinking, but he did not improve on the sociometric measures. Robert improved on the sociometric measures, but not on task-relevant self-verbalizations, Mazes, Block Design, or consequential or means-end thinking. While these results are encouraging, limitations of the study limit generalizability of findings. Studies of the long-term benefits of training are needed to determine the cost effectiveness of incorporating parents as cotherapists in social cognitive problem-solving therapy. 相似文献
It is a rather safe statement to claim that the social dimensions of the scientific process are accepted in a fair share of studies in the philosophy of science. It is a somewhat safe statement to claim that the social dimensions are now seen as an essential element in the understanding of what human cognition is and how it functions. But it would be a rather unsafe statement to claim that the social is fully accepted in the philosophy of mathematics. And we are not quite sure what kind of statement it is to claim that the social dimensions in theories of mathematics education are becoming more prominent, compared to the psychological dimensions. In our contribution we will focus, after a brief presentation of the above claims, on this particular domain to understand the successes and failures of the development of theories of mathematics education that focus on the social and not primarily on the psychological. 相似文献
Abstract The incidence of aggression and violence in schools is approaching epidemic proportions. Unfortunately, few teacher education programs offer coursework designed to prepare school personnel to face the mounting challenge of student aggression. Drawing upon the accumulated literature, changes are discussed in the content of teacher education programs that would prepare teachers to effectively address student violence. Assertions are made that colleges of education must assume leadership roles in redefining professional boundaries to prepare all school personnel to combat student aggression. Lastly, arguments are presented for strengthening university and public school collaboration to promote programs designed to curb the rising tide of student aggression and violence. 相似文献
The analysis of longitudinal data in education is becoming more prevalent given the nature of testing systems constructed for No Child Left Behind Act (NCLB). However, constructing the longitudinal data files remains a significant challenge. Students move into new schools, but in many cases the unique identifiers (ID) that should remain constant for each student change. As a result, different students frequently share the same ID, and merging records for an ID that is erroneously assigned to different students clearly becomes problematic. In small data sets, quality assurance of the merge can proceed through human reviews of the data to ensure all merged records are properly joined. However, in data sets with hundreds of thousands of cases, quality assurance via human review is impossible. While the record linkage literature has many applications in other disciplines, the educational measurement literature lacks details of formal protocols that can be used for quality assurance procedures for longitudinal data files. This article presents an empirical quality assurance procedure that may be used to verify the integrity of the merges performed for longitudinal analysis. We also discuss possible extensions that would permit merges to occur even when unique identifiers are not available.相似文献
The article examines the theory and practice of focus groups in adult education research. Three theoretical positions are described: radical hermeneutic, moderate interpretative and pragmatic realistic position trying to bridge the gap with positivist research. This last position has been chosen as the departure point for a further analysis of the focus group elements, which relate to validity and reliability. The research examines four European research projects in the field of adult education. The most important and surprising data are presented with reference to both socio-psychological and technical problems in the use of this method. The results highlight the importance and dynamics of all the elements discussed. 相似文献
The WWW is increasingly used as a medium to support education and training. A course at the University of Twente in which groups of students collaborate in the design and production of multimedia instructional materials has now been supported by a website since 1995. Workflow was integrated with other components in the website to investigate whether workflow can help instructors and students to have a better overview of group progress. Our evaluation shows that the introduction of workflow does provide added value. Another outcome of the experiment is that the transfer of a business application (workflow) into the educational domain has highlighted some differences and similarities between educational and business processes. This article explores some of these issues as highlighted by the application of workflow in education. 相似文献