Energy expenditure in professional flat jockeys using doubly labelled water during the racing season: Implications for body weight management     

George Wilson  Daloni Lucas  Catherine Hambly  John R. Speakman  James P. Morton 《European Journal of Sport Science》2018,18(2):235-242

To formulate individualized dietary strategies for jockeys, it is vital that energy requirements are quantified. We measured total energy expenditure (TEE) over two separate weeks in spring and summer using doubly labelled water in a group of male flat jockeys (n?=?8, 36.9?±?5.7 years, 164?±?8?cm, 54.6?±?2.5?kg). Total energy intake (TEI) was self-recorded, as were all riding and structured exercise activity. Mean daily TEE was 10.83 (±2.3) and 10.66 (±1.76) MJ, (p?=?.61) respectively. Self-reported TEI were 6.03 (±1.7) and 5.37 (±1.1) MJ (p?=?.40), respectively, and were significantly lower than TEE (p?=?.01). Mean race rides were 17 (±6) and 13 (±3; p?=?0.37) and horses ridden at morning exercise were 8 (±6) and 7 (±4; p?=?.77) respectively. Additional structured exercise was 76.25 (±95.1) and 52.5 (±80.9) min per week (p?=?.35), respectively. At the individual level, TEE was related to body mass and the level of non-racing physical activity, but not riding. Physical activity levels for TEE were 1.76 (±0.37) and 1.69 (±0.27; p?=?.59) and appear modest when compared with other athletes, and similar to age-matched non-athletes, suggesting that conventional sport-specific nutritional recommendations do not appear applicable. The large discrepancy between TEE and TEI suggests significant under reporting of dietary intake. These data now provide an appropriate framework from which to formulate jockey nutritional guidelines to promote the ability to achieve the daily weight target and improve athlete welfare.  相似文献   

Parasympathetic activity delayed after self-paced exercise     

Lucas Rosiello Trojbicz  Mayara Vieira Damasceno  Leonardo Alves Pasqua  Arthur Fernandes Gáspari  Adriano Eduardo Lima-Silva 《European Journal of Sport Science》2018,18(6):842-850

The main purpose of this study was to compare the effect of the constant load and self-paced exercise with similar total work on autonomic control after endurance exercise. Ten physically active men were submitted to (i) a maximal incremental exercise test, (ii) a 4-km cycling time trial (4-km TT), and (iii) a constant workload test with identical total external work performed at 4-km TT. Gas exchange was measured throughout the tests, while blood lactate, heart rate, and heart rate variability (HRV) were measured during the passive recovery. Power output measured at the last lap (i.e. 3600–4000?m) of 4-km TT (316?±?89?W) was statistically higher than power output measured at the end of the constant workload exercise (211?±?42?W). The 4-km TT produced higher values of blood lactate concentration (8.8?±?2.1?mmol?L^?1) than the constant workload test (7.8?±?2.1?mmol?L^?1). The heart rate recovery measured at 60?s (constant workload: 37?±?7?bpm; 4-km TT: 30?±?6) and 120?s (constant workload: 57?±?9?bpm; 4-km TT: 51?±?9?bpm) were higher in the constant workload than in the self-paced exercise. The HRV (i.e. RMSSD30s) was statistically higher in the constant load exercise measured at 120, 420, 450, 480, 540, and 570?s than the self-paced exercise. These findings suggest that the autonomic control responses were dependent of the endurance exercise modalities, with parasympathetic activity being delayed after self-paced exercise, as evidenced by post-exercise heart rate indices.  相似文献   

Development,construct validity and test–retest reliability of a field-based wheelchair mobility performance test for wheelchair basketball     

Annemarie M. H. de Witte  Marco J. M. Hoozemans  Monique A. M. Berger  Rienk M. A. van der Slikke  Lucas H. V. van der Woude  Dirkjan Veeger 《Journal of sports sciences》2018,36(1):23-32

The aim of this study was to develop and describe a wheelchair mobility performance test in wheelchair basketball and to assess its construct validity and reliability. To mimic mobility performance of wheelchair basketball matches in a standardised manner, a test was designed based on observation of wheelchair basketball matches and expert judgement.

Forty-six players performed the test to determine its validity and 23 players performed the test twice for reliability. Independent-samples t-tests were used to assess whether the times needed to complete the test were different for classifications, playing standards and sex. Intraclass correlation coefficients (ICC) were calculated to quantify reliability of performance times.

Males performed better than females (P < 0.001, effect size [ES] = ?1.26) and international men performed better than national men (P < 0.001, ES = ?1.62). Performance time of low (≤2.5) and high (≥3.0) classification players was borderline not significant with a moderate ES (P = 0.06, ES = 0.58). The reliability was excellent for overall performance time (ICC = 0.95).

These results show that the test can be used as a standardised mobility performance test to validly and reliably assess the capacity in mobility performance of elite wheelchair basketball athletes. Furthermore, the described methodology of development is recommended for use in other sports to develop sport-specific tests.  相似文献   

Residual force enhancement in human skeletal muscles: A systematic review and meta-analysis     

Daiani de Campos  Lucas B.R.Orssatto  Gabriel S.Trajano  Walter Herzog  Heiliane de Brito Fontana 《运动与健康科学(英文)》2022,11(1):94-103

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Model-based reasoning in a year 10 classroom     

Sally-Anne Stephens  Campbell J. McRobbie  Keith B. Lucas 《Research in Science Education》1999,29(2):189-208

Studies have shown that secondary school students experience difficulties making scientific models meaningful, yet explanatory models are central to the development of scientific understanding. This study investigated the extent and nature of students' model-based reasoning in a laboratory investigation. It was an interpretive study involving a single Year 10 Science class investigating the influence of six factors on electrical resistance. Before commencing their practical investigations students were re-familiarised with the “electron drift” model of metals. Data sources included videotapes of classroom interactions, audiotaped interviews with students, student workbooks showing their experimental procedures and results, and explanations of those results. The research suggests that spontaneous use of the model in explanations increased over the duration of the task but that the explanations were restricted mainly to model-based reasoning with lower order relational mapping. Even after further formal instruction on the model after the initial experimental investigations, many students were still unable to use the model effectively, displaying mainly the same level of reasoning. As model-based reasoning is an important part of learning some aspects of science, it is imperative that science educators take appropriate steps to facilitate the development of such reasoning in appropriate contexts.  相似文献   

The advising system: An alternative model related to the evaluation of self-directed learning     

James T. Decker Ph.D.  John R. Redhorse Ph.D.  Gerald R. Lucas Ph.D. 《Innovative Higher Education》1978,3(2):68-74

The proposed advising model focuses on creative learning. To operationalize such a model, there must be not only structural but behavioral changes in the existing system. This requires that professional educators have special concern for the quality of relationships between faculty and students. In a program which focuses on creative learning, most students need assistance in developing the understanding and skill necessary for creative learning. An alternative advising model is proposed, therefore, which enhances the behavioral requirements. The alternative model views the advising function as a teaching-consulting function with a priority goal of helping the student learn the art of self-evaluation as a prerequisite to life-long learning.  相似文献   

Testing Role Models’ Differential Effect on Use of Aggressive Compliance Gaining Strategies     

Kristen Eis Cvancara  Lucas Youngvorst  Virginia Otto  Christopher Brown 《Communication quarterly》2016,64(1):36-54

Using a repeated measures design, this empirical study confirmed that a differential relationship exists between significant role models’ use of aggressive compliance gaining strategies (ACGS) and an individual’s use of the same in romantic and non-romantic interactions. As expected, peer use was found to have the strongest relationship to individual use of ACGS with romantic partners. Unexpected was the similarity in strength of parent and peer use to individual use of ACGS with non-romantic partners. Relevance and opportunity are mechanisms used to explain role model impact as an antecedent variable of ACGS use. Future studies to advance theory regarding aggressive communication are discussed.  相似文献   

Student teachers' attitudes toward science and science teaching     

Keith B. Lucas  John H. Dooley 《科学教学研究杂志》1982,19(9):805-809

Attitudes toward science and science teaching are the subject of a mounting body of research on teachers. A widely used instrument developed by researchers in the United States appears to be relevant to the Australian context and was considered appropriate for measuring attitudes of preservice student teachers attending a College of Advanced Education in Brisbane. The findings suggest that much more effort needs to be concentrated on fostering desirable attitudes toward science and the teaching of science among future primary school teachers.  相似文献   

The effectiveness of orienting students to the physical features of a science museum prior to visitation     

David Anderson  Keith B. Lucas 《Research in Science Education》1997,27(4):485-495

This paper reports on a study in the area of informal science education in the contexts of science museums. The research focused upon two areas: first, perceived novelty and its effect on cognitive learning in year eight students visiting an interactive science museum; second, the links between exhibits which were most frequently recalled and exhibits which students later recalled as being interesting and puzzling. Results on a post-test of cognitive learning of concepts and principles associated with the exhibits suggested that students who underwent novelty reducing pre-orientation to the physical environment and had prior visitation experience learned more than their counterparts. Gender did not influence learning when perceived novelty level and prior exposure were considered. Furthermore, the most frequently recalled exhibits shared a combination of characteristics such as large physical size, prominence in the exhibit galleries, and the diversity of sensory modes that they employed. Finally, it appears that cognitive learning is likely to occur for exhibits which are most memorable.  相似文献   

Factors of success: building and sustaining teaching professional development opportunities for doctoral students and postdocs     

Lucas B. Hill  Ann E. Austin  Bipana Bantawa  Julia N. Savoy 《高等教育研究与发展》2019,38(6):1168-1182

ABSTRACT

This paper examines the key issues and elements to consider in developing and sustaining teaching development programs for doctoral students and postdoctoral scholars in connection to a large multi-institutional, higher education reform network. Based on interviews with 47 participants at eight member institutions and the central administration of the Center for the Integration of Research, Teaching, and Learning (CIRTL), we found five major components: campus culture, the program’s organizational placement, program leadership, program logistics, and the benefits acquired from adopting and adapting network ideas, knowledge, and resources.  相似文献