The Development of Curricular Knowledge: A Case of Problematic Pedagogical Content Knowledge during Advanced Knowledge Acquisition

Abstract

The study examined, what and how 12 K-8 physical education teacher education (PETE) majors learned, about a movement approach that was discrepant from their experiences with physical education. This article describes one portion of the findings: what and, how PETE majors learned about a movement approach to game play/strategy and mechanisms of advanced knowledge acquisition that contributed to confusion about this topic. Analytic induction and constant comparison were used to analyze qualitative data from interviews, observations, and relevant documents. Eleven PETE majors initially maintained partial or inaccurate conceptions about a movement approach to game play/strategy or taught the content in ways that were inconsistent with their goals for physical education, their knowledge about learning and teaching game skills, and the information presented by faculty and cooperating teachers. Interacting with students' prior knowledge and what and how faculty taught, the following learning mechanisms contributed to confusion: (a) overgeneratizing a contrast between a movement and traditional approach, (b) forming associations prior to adequate differentiation, and (c) overrelying on bottom-up thinking when intially developing lesson/unit progressions.     

Epistemology and the Use of the .05 Level of Significance: A Rebuttal to Inductionism

In the first part of this study, the football potential of 67 football players was predicted from their scores on a football-potential test. The test battery consisted of motor ability items as well as football skill items. Substantial correlations were obtained between most test items and the test criterion, the sum of T scores. Size, as depicted by McCloy's classification index (C.I.), had a negative, nonsignificant correlation with the criterion. The discriminative power of the battery was evidenced by the highly significant correlation between the test criterion and the coaching staff's ranking of individual players (rho = .840). It was concluded that athletic potential in football can be predicted by testing. In the second part of the study, football teams from three different strata of competition were evaluated on the basis of the test battery. The battery substantiated a step-wise progression between the teams on most items, with significant differences being noted. The test showed validity, in that the test criterion (the sum of T scores) was significantly different between the teams.     

Teaching within a Curricular Zone of Safety: School Culture and the Situated Nature of Student Teachers' Pedagogical Content Knowledge

Abstract

The purpose of this paper is to continue the theoretical delineation of the nature of pedagogical content knowledge. Two student teachers were observed teaching an elementary games and high school sport unit and interviewed in depth about their lessons, biography, pedagogical content knowledge, and aspects of the school culture. Data were analyzed by constant comparison and analytic induction. Trustworthiness was established through member checks and triangulation. In the high school, both student teachers tried to use extending and refining tasks, as they had in the elementary school. But, when confronted with aspects of the high school culture, both retreated to a curricular zone of safety relying on application tasks. This zone, the defining aspect of their pedagogical content knowledge of teaching sports, emerged from and was constituted by the relations among goals, capabilities, teaching, inadequate pedagogical content knowledge, and aspects of the school culture. It is argued that situated and cultural orientations contribute to psychological orientations currently used to delineate pedagogical content knowledge. A curricular zone of safety is offered as a concept that helped account for the emergence and persistence of particular ways of knowing content.     

运动对血清瘦素水平的影响

采用文献资料等研究方法,对肥胖基因及其表达产物——瘦素（Leptin）的结构、功能及其作用机制,Leptin的分泌和调节,国内外有关瘦素的生理学作用,瘦素与运动关系的研究近况,不同强度和时间的运动对血清瘦素的影响进行综述,并对未来研究前景提出展望。结论表明：瘦素在运动训练中具有潜在的价值,可以用血液中的瘦素水平来监控运动训练,了解不同运动对瘦素的作用及机制,开．展瘦素与运动的关系及其相关的神经内分泌和免疫等方面的系统研究具有重要意义。     

The immune response to short-duration exercise in trained,eumenorrhoeic women

Few studies have characterised the immune response to exercise of different intensities and durations in women. In those that have, baseline hormone levels and training status were not always adequately controlled for. Here, leucocyte and cytokine profiles of 11 aerobically trained, eumenorrhoeic females (33 ± 5 years) in the early follicular phase of the menstrual cycle were characterised after 30-min exercise at 3 intensities: 90% lactate threshold (LT), LT, and 110% LT. Proposed cytokine response mediators were quantified: plasma lactate and basal oestradiol concentrations. Intensity-dependent increases occurred in total white blood cells and lymphocyte counts (P < 0.001). Elevated plasma IL-6 and IL-1ra concentrations post-exercise [F = 12.38, P < 0.01 and F = 7.65, P < 0.05, respectively] were not intensity-dependent, indicating that cytokine release may be better associated with exercise duration than intensity in trained women. Changes in plasma IL-1ra and basal oestradiol (ρ = ?0.893, P < 0.01) were correlated at intensities above LT only. These findings suggest a role for plasma sex hormones in moderating the exercise-induced immune response in women. However, the associations observed did not account for the magnitude of the cytokine response observed, and future studies should explore contributions of other potential mediators following short-duration exercise.     

Age and Cardiovascular Response to Submaximal Treadmill Exercise in Males

Abstract

The primary purpose of this investigation was to determine the relative importance of the attributes that student–athletes use when determining their choice of a university. A second purpose was to compare previous athletic institutional choice studies with the results of this study to determine if the most important attributes were similar and to compare and contrast methodologies. Six hundred five Division I student–athletes (344 baseball players and 261 softball players) from all eight national geographic regions of the NCAA participated in this study. The experimental procedure was based on Information Integration Theory and a 2¹⁰ fractional factorial design that resulted in 32 “choice sets.” These choice sets were composed of universities described by 10 attributes. This framework required that the student–athletes choose from among three university profiles, thereby realistically simulating the decision process. The results for the aggregate sample show that the “Amount of Scholarship” attribute was the most important factor in the institutional choice process. Many demographic variables were analyzed (sex, race, amount of scholarship received as a freshman, amount of perceived financial need, self-reported grade-point average, questionnaire completion procedures, in-state/out-of-state status, NCAA region, and rank in high school) in conjunction with the choice set data in a post-hoc framework. The results for a subset of these variables are reported in this paper; differences (in the order of importance of the attributes) were found among groups. A primary finding of this study is that a student–athlete's perceived financial need has a critical impact on the institutional choice process. A second important finding is that, although “Amount of Scholarship” was determined to be the most important attribute, this result stands in stark contrast to previous studies that have investigated the institutional choice process of student–athletes.     

女子中长跑运动员肌氧含量与个体乳酸阈关系的探讨

为解决运动训练中生物医学参数的在体、无损、实时监测，利用基于光漫射理论的三波长近红外肌氧监测系统，对受试在功率自行车上做等级性递增负荷运动时局部骨骼肌组织中的肌氧含量的相对变化进行了在体、连续、实时监测与分析，并与血乳酸浓度、运动强度和“个体乳酸阈”等进行对比研究。结果表明：肌氧含量的相对变化与血乳酸浓度、“个体乳酸阈”和运动强度具有密切的关系。为用无损监测肌氧含量的相对变化取代有损监测血乳酸提供了实践依据，为运动员的生理机能评定和运动训练效果的生理学评价引入新的生物学测试技术和方法。     

Gender influence on the adaptation of atrial performance to training

Background: High-intensity training has been associated with atrial remodelling and arrhythmias in men. Our purpose was to analyse atrial performance in female endurance athletes, compared to male athletes and controls. Methods: This was a cross-sectional study. We included four groups: female athletes, females controls, male athletes and male controls. Left (LA) and right atrial (RA) volumes and function were assessed using 2D and speckle-tracking echocardiography to determine peak atrial strain-rate at atrial (SRa) and ventricular contraction (SRs), as surrogates of atrial contractile and reservoir function, respectively. ANOVA and Bonferroni’s statistical tests were used to compare variables among groups. Results: We included 82 subjects, 39 women (19 endurance athletes, 20 controls) and 43 men (22 endurance athletes, 21 controls). Mean age was similar between groups (36.6?±?5.6 years). Athletes had larger bi-atrial volumes, compared to controls (women, LA 27.1 vs. 15.8?ml/m², p?<?0.001; RA 22.31 vs. 14.2?ml/m², p?=?0.009; men, LA: 25.0 vs. 18.5?ml/m², p?=?0.003; RA 30.8 vs. 21.9?ml/m², p?<?0.001) and lower strain-rate (women, LASRa ?1.60 vs. ?2.18?s^?1, p?<?0.001; RASRa ?1.89 vs. ?2.38?s^?1, p?=?0.009; men, LASRa ?1.21 vs. ?1.44?s^?1, p?=?1; RASRa ?1.44 vs. ?1.60?s^?1, p?=?1). However, RA indexed size was lower and bi-atrial deformation greater in female athletes, compared to male athletes. Conclusions: The atria of both male and female athletes shows specific remodelling, compared to sedentary subjects, with larger size and less deformation at rest, particularly for the RA. Despite a similar extent of remodelling, the pattern in women had greater bi-atrial myocardial deformation and smaller RA size.     

Response of brain-derived neurotrophic factor to combining cognitive and physical exercise

Purpose: Brain-derived neurotrophic factor (BDNF) is well known for its potential to promote brain plasticity. It has been proposed that combining cognitive and physical exercise (CCPE) may have the potential to generate more synergistic benefits in cognitive function than either cognitive exercise (CE) or physical exercise (PE) alone. The purpose of this study was to examine acute responses of peripheral BDNF levels and cognitive performance to CE, PE, and CCPE.

Methods: Thirteen healthy adult men participated in four experimental sessions; a 30-min CE, a 30-min cycling PE at an intensity of 60% peak oxygen uptake, a 30-min CCPE at the same intensity as PE, and a 30-min session of complete rest. Plasma BDNF levels and cognitive performance were measured before and after each session.

Results: Both PE and CCPE significantly increased plasma BDNF levels (p?p?≥?.05), and there was no significant difference in peripheral BDNF levels between PE and CCPE (p?≥?.05). No session induced a significant change in cognitive performance (p?≥?.05).

Conclusions: Our study suggests that CE and PE have different responses of peripheral BDNF levels and that CCPE had no additional or synergistic effect on peripheral BDNF levels compared with PE alone. This study offers further insights into the potential mechanisms underlying the respective roles of CE, PE, and CCPE for peripheral BDNF levels and cognitive performance.     

内容与方法: 内隐自尊的探索与问题

目的：观察以高脂膳食诱导的C57BL／6J小鼠脂肪肝和血脂的变化以及有氧运动对它们的改善作用。方法：以高脂膳食诱导的脂肪肝小鼠为模型．分析有氧运动20周后脂肪肝及血清TC，TG，HDL—c，LDL-c和VLDL—c水平的变化。结果：H组血清TC、TG、LDL—c水平显著高于其他各组，而VLDL-c显著降低：RE组血清TG、TC、LDL-c的水平显著降低，且与N组没有显著差异；RS组TG、TC、LDL—c有降低的趋势，但显著高于正常对照组；N组血清HDL-c显著低于HS、RS和RE组（P〈0．05），而HS、RS与RE组之间无显著差异；肝脏中脂滴数高脂膳食组（H组）显著高于其他各组，恢复正常膳食不运动组（RS组）显著高于恢复正常膳食结合运动组（RE组），正常对照组（N组）与RE组间无显著差异；脂肪肝的病变程度与TC、TG、LDL-c呈显著正相关，与VLDL—c呈显著负相关，与HDL—c呈正相关，但无显著性。结论：运动与改善膳食结构相结合，对高脂所致的高脂血症和脂肪肝．比单纯的改善膳食结构具有更明显的治疗效果。     

Effects of plyometric jump training in female soccer player’s vertical jump height: A systematic review with meta-analysis

ABSTRACT

To assess the effects of plyometric jump training (PJT) in female soccer player’s vertical jump height, a review was conducted using the data sources PubMed, MEDLINE, Web Of Science and SCOPUS. Only peer-review articles were included. To qualify for inclusion in the meta-analysis, studies must have included (i) a PJT programme of at least 2 weeks, (ii) cohorts of healthy female soccer players with no restriction for age, (iii) a control group, (iv) a measure of countermovement jump (CMJ). The inverse variance random-effects model for meta-analyses was used. From 7,136 records initially identified through database searching, 8 were eligible for meta-analysis, comprising 9 training groups (n = 99) and 9 control groups (n = 94). The magnitude of the main effect was moderate (ES = 1.01 [95%CI = 0.36–1.66], Z = 3.04, p = 0.002). Sub-group analyses were performed (i.e., PJT frequency, duration and total number of sessions), revealing no significant subgroup differences (p = 0.34–0.96). Among the studies included in this review, none reported injury or other adverse effects. In conclusion, PJT is effective in female soccer players for the improvement of vertical jump height. In future, research must identify specific dose–response relationships following PJT, particularly in the long term.     

不同锻炼方法对中老年妇女身体形态与机能影响的探析

采用测量法与对比评价研究的方法 ,分析了体育锻炼 (传统健身锻炼、长跑、跳舞 )对中老年妇女身体形态与机能状况的影响。证实体育锻炼能增强中老年妇女的体质及心肺功能 ,具有既健身又健美的作用。健身舞蹈是中老年妇女值得选择的一种效果理想的健身锻炼方法     

女大学生心血管功能对健身运动处方锻炼的应答

近1 0年对大学生体质健康的研究表明:大学生心功能有下降的趋势。因此,重视大学生心血管功能锻炼已刻不容缓。研制不同内容的健身运动处方,对女大学生进行课外体育锻炼实验,观察心血管功能对不同内容健身运动处方锻炼的应答。结果表明,女大学生的心血管功能对制定的健身运动处方产生不同程度的良性应答。其中,全面锻炼(1组)使用的健身运动处方对改善血管功能效果最明显。     

Multidisciplinary predictors of adherence to contemporary dance training: findings from the UK Centres for Advanced Training

Little is known about the predictors of adherence in a dance context. The aim of this study was to investigate adherence to a dance talent programme using a multidisciplinary set of variables representing psychological correlates of adherence, maturation and physical factors relating to dance talent. Psychological (passion, motivational climate perceptions, eating attitudes), physical competence (vertical jump height, handgrip strength, hamstring flexibility, external hip rotation, aerobic fitness), and maturation-related (age of menarche) variables were gathered from female students enrolled on a dance talent programme. Participation behaviour (adherence/dropout) was collected from the talent programme’s records approximately two years later. Logistic regression analysis of 287 participants revealed that greater levels of harmonious passion predicted greater likelihood of adherence to the programme, and greater ego-involving motivational climate perceptions predicted less likelihood of adherence. Neither measures of physical competence nor maturation distinguished adhering from dropout participants. Overall, the results of this study indicate that psychological factors are more important than physical competence and maturation in the participation behaviour of young talented dancers.     

应用低氧运动时动脉血症和通气反应指标预测急性高原反应的探索研究

目的:通过测试运动时低氧血症和低氧通气指标的变化来探索预测急性高原反应(actue mountain sickness,AMS)的可行性指标,为降低高原旅居人群罹患AMS的风险和提高其生活质量提供参考.方法:23名普通男性大学生于低氧舱(～4400 m,F1O2 11.8％～11.6％)暴露6h,分别于低氧暴露第0.5h、2h、4h和6h评测受试者急性高原反应(LLS量表),有头痛症状且LLS评分≥3者,定为AMS组.受试者进舱休息30 min后进行30 min运动心肺功能测试:于卧式功率车上安静5min后以80 W恒定负荷(60 rpm)仰卧蹬车20min,恢复5min.每5min末记录RPE、HR、SpO2、BP和低氧通气反应相关指标.据测试指标计算AMS组和nonAMS组低氧通气指数和低氧心功能指数差异.取有显著性差异的指标作为自变量与LLS评分拟合得出预测方程.结果:急性低氧暴露结束时AMS发生率为27％.低氧安静时AMS组与nonAMS组RPE、HR、SpO2、VE、Vr和fR无显著性差异.低氧运动时AMS组SpO2显著低于nonAMS组(P＜0.05),运动5min时达最低点.低氧运动5min时AMS组V3显著低于nonAMS组(分别为41.4±4.61/min和46.7±4.61/min,P＜0.05).低氧运动时SpO2和VE预测LLS评分的非线性方程分别为:LLS=0.0295(SpO2)2-4.5269(SpO2) +174.34(R2 =0.7473,P＜0.001)和LLS=0.0352(VE)2 -3.4987(VE)+87.729(R2=0.307,P=0.053);SpO2与VE呈中度相关(R=0.394,P＜0.05).结论:低氧运动时动脉血症指标SpO2和通气指标VE可作为预测AMS的有效指标,SpO2的预测准确性高于VE,运动时SpO2与VE呈中度相关.从测试的简便、可靠角度考虑,运动时SpO2的变化具有较好的应用前景.     

学校体育对学生在应对公共突发事件时的心理素质锻炼模式研究

随着突发公共事件的不断发生,我们的校园和学生都受到了严重的影响。那么面对突发情况,我们的学校体育如何锻炼和提高学生应急心理素质已经越来越被人们重视。本文主要采用文献资料、专家访谈法和实验法,对学生在应对突发事件时的心理素质进行剖析,通过学校体育的教学手段、方法和内容等方面探讨锻炼学生应急避险的心理素质锻炼模式,以供老师和学生进行参考。     

Heart Rate Holter Monitoring of 6- and 7-Year Old Children with Insulin Dependent Diabetes Mellitus Cardiovascular and Short Term Metabolic Response to Exercise: A Pilot Study

Abstract

This study examined whether gender and/or training were related to the exercise-induced changes in plasma concentrations of growth hormone (GH), prolactin (PRL), triiodothyronine (T₃), and thyroxine (T₄). Twenty subjects (male and female 10-km runners; untrained males and females) ran on a treadmill for 30 win at 80% of previously determined maximum heart rate. Blood samples were taken through an indwelling catheter from an antecubital vein at ?30, 0, +15, +30 min of the test and 30 min of recovery. Reded temperature rose significantly (p < .01) at +15 and +30 min with concomitant rise in GH concentration, but PRL, T₃, and T₄ were not affected by the exercise. We concluded that a 30-min run at 80% of maximum heart rate is associated with higher concentrations of GH but not of PRL, T₃, and T₄ Neither training state nor gender affected the aforementioned results.     

Oxygen uptake during mini trampoline exercise in normal-weight,endurance-trained adults and in overweight-obese,inactive adults: A proof-of-concept study

Objectives: To examine cardiorespiratory exertion during mini trampoline exercises of different intensities in both endurance-trained athletes and overweight-obese adults. Methods: Physically healthy participants (Group A: normal-weight, endurance-trained athletes; Group B: inactive, overweight-obese adults) participated in two measurement appointments and three training sessions in between appointments, in which participants familiarized themselves with the use of the mini trampoline and the execution of the exercises. The primary outcome was the ?O_2peak for each of the six mini trampoline exercises relative to the ?O_2peak as established during an all-out exercise test on a bike ergometer during the first measurement appointment. Secondary outcomes were average ?O₂ as well as maximum and average heart rate. Results: The six mini trampoline exercises generated ?O_2peak values between 42% and 81% in the endurance-trained athletes and between 58% and 87% in the overweight-obese participants, both in relation to the bike ergometer ?O_2peak. Average ?O₂ values ranged from 35% to 69% (endurance-trained athletes) and from 48% to 71% (overweight-obese participants), depending on exercise. Average heart rate likewise lay in a range that can be categorized as moderate-to-vigorous aerobic exercise for both groups. A moderate-to-strong correlation (0.658 to 0.875, depending on exercise) between bike ergometer ?O_2peak and mini trampoline ?O_2peak was found for all six exercises. Conclusions: Mini trampoline exercise has the potential to produce training intensities that concur with established exercise guidelines. The exercise intensity is self-adjusting and allows for an effective and safe workout for different users with a wide range of fitness levels.