Reliability of power and velocity variables collected during the traditional and ballistic bench press exercise

This study aimed to examine the reliability of different power and velocity variables during the Smith machine bench press (BP) and bench press throw (BPT) exercises. Twenty-two healthy men conducted four testing sessions after a preliminary BP one-repetition maximum (1RM) test. In a counterbalanced order, participants performed two sessions of BP in one week and two sessions of BPT in another week. Mean propulsive power, peak power, mean propulsive velocity, and peak velocity at each tenth percentile (20–70% of 1RM) were recorded by a linear transducer. The within-participants coefficient of variation (CV) was higher for the load–power relationship compared to the load–velocity relationship in both the BP (5.3% vs. 4.1%; CV ratio = 1.29) and BPT (4.7% vs. 3.4%; CV ratio = 1.38). Mean propulsive variables showed lower reliability than peak variables in both the BP (5.4% vs. 4.0%, CV ratio = 1.35) and BPT (4.8% vs. 3.3%, CV ratio = 1.45). All variables were deemed reliable, with the peak velocity demonstrating the lowest within-participants CV. Based upon these findings, the peak velocity should be chosen for the accurate assessment of BP and BPT performance.     

Larger strength losses and muscle activation deficits in plantar flexors induced by backward downhill in reference to distance-matched forward uphill treadmill walk

We tested the hypothesis that backward downhill walking (eccentric component) impairs both voluntary activation and muscle contractile properties in the plantar flexors and delays recovery as compared to a gradient and distance-matched uphill walk. Fourteen males performed two 30-min walking exercises (velocity: 1?m/?s; grade: 25%; load: 12% of body weight), one downhill (DW) and one uphill (UP), in a counterbalanced order, separated by 6?weeks. Neuromuscular test sessions were performed before, after, 24-, 48- and 72-h post-exercise, including motor nerve stimulations during brief (5?s) and sustained (1?min) maximal isometric voluntary contractions of the plantar flexors. DW (?18.1?±?11.1%, P?P?=.15), decreased torque production during brief contractions for at least three days post-exercise (P?P?P?=?.024) and DW (?25.6?±?10.3%, P?P?=?.001) was lower in DW than UP. Peak twitch torque and maximum rates of torque development and relaxation were equally reduced after UP and DW (P?P?P?>?.05). Using a direct comparison, the capacity to drive the plantar flexors during sustained contractions remains sub-optimal during the three-day recovery period in response to non-exhaustive, downhill backward walking in reference to an uphill exercise matched for distance covered.     

The effect of sex and localised fatigue on triceps surae musculoarticular stiffness

Purpose: The main purpose of this study was to investigate the influence of fatigue on musculoarticular stiffness (MAS) of the ankle joint across sexes. Methods: Twenty-seven males and 26 females participated in the study. After baseline assessment of MAS and related variables, localised fatigue was induced in triceps surae using the standing heel-rise test during which the subjects were instructed to lift and drop the heel at a frequency of 0.5?Hz. When subjects were unable to continue due to exhaustion the test was terminated and another MAS test was performed soon after. Results: Significant higher triceps surae MAS was found in men compared to women (p?p??1 and from 14.5 to 13.9?KN?m^?1 in men and women, respectively. Percentage changes revealed, however, that in relative terms the changes in all the variables evaluated were similar (p?>?.01) between sexes, with MAS less than 5%. Conclusion: Despite the sex-related differences at baseline, fatigue seems to affect biomechanical properties of the ankle joint similarly in men and women.     

The “Species” Concept as a Gateway to Nature of Science

The nature of science (NOS) is a primary goal in school science. Most teachers are not well-prepared for teaching NOS, but a sophisticated and in-depth understanding of NOS is necessary for effective teaching. Some authors emphasize the need for teaching NOS in context. Species, a central concept in biology, is proposed in this article as a concrete example of a means for achieving increased understanding of NOS. Although species are commonly presented in textbooks as fixed entities with a single definition, the concept of species is a highly discussed one in the science and the philosophy of biology. A multitude of species concepts exist, reflecting both the views and interests of researchers and their utility in different organism groups. The present study serves to address the following questions: How do textbooks in Norwegian primary and lower secondary schools present the concept of species? Can inquiries into the concept of “species” serve to highlight aspects of NOS? A review of the available literature on species and species concepts in school is also performed. In the schoolbooks, the biological species concept is commonly used as the main definition, whereas the morphological species concept is represented by additional remarks of similarity. The potential and pitfalls of using the species concept for teaching NOS are discussed, with NOS being discussed both as a family resemblance concept and as a consensus list. Teacher education is proposed as a starting point for inducing a more sophisticated view of biology into schools.     

Does Parent–Child Discussion of Peer Provocations Reduce Young Children's Hostile Attributional Bias?

Two studies investigated whether parent–child discussion of peer provocations reduces young children's hostile attributional bias. Study 1 (N = 109, age 4–7)—an observational study—showed that parent–child discussion of nonhostile attributions (when reading a picture book) predicted reductions in children's hostile attributional bias from pre‐ to postdiscussion. Study 2 (N = 160, age 4–6)—an experimental study—showed that stimulating parents to discuss either nonhostile attributions or normative beliefs (vs. a control condition) reduced children's hostile attributional bias in response to hypothetical vignettes, but not in response to a staged peer provocation. These findings suggest that by framing social situations, parents may help their children perceive less hostility in their social worlds.     

Engagement,passivity and detachment: 16‐year‐old students’ conceptions of politics and the relationship between people and politics

While there is a wealth of literature on young people and politics, most studies have examined their interest, trust and participation in politics as well as their attitudes toward and knowledge about formal politics. Little is known, however, about young people and the concept of politics. This article investigates 16‐year‐old students’ perceptions of the concept of politics and their conceptions of the relationship between people and politics. This knowledge is valuable for citizenship and social studies education, as an increasingly polarised political climate poses challenges to democratic politics and, consequently, to young people's political engagement and participation. In this study, semi‐structured interviews were conducted with nine students at five Norwegian upper secondary schools. The students varied in their interest and involvement in politics. A main finding is that the students perceived politics as processes related to shaping society, as decisions and activities related to ruling a country, and as the activities of discussion and debate. Three conceptions of the relationship between people and politics are presented: engagement, passivity, and detachment. In addition, while the 16‐year‐olds participated in political discussions privately and at school, they stated that they did not participate in political discussions in social media. Implications for citizenship and social studies education include the need to strengthen the bottom‐up perspective on politics and focus on in‐depth understanding of political processes and tools and methods of social‐scientific enquiry, as well as providing students with opportunities for and practice with handling opposition in political discussions online.     

The moderating role of resilience in the relationship between academic burnout and the perception of psychological health in nursing students

Abstract

The objective of this study was to analyse the role of resilience in the dimensions of academic burnout syndrome and psychological health in a sample of nursing students. A battery of questionnaires was administered to 218 nursing students, all of whom were in the second year of their degree at the University of Murcia (Spain). The applied protocol used the CD-RISC 10 scale for the measurement of resilience, the burnout scale MBI, and the GHQ-12 questionnaire to assess psychological health. The findings showed a significant relationship between resilience and burnout, emotional exhaustion, and self-efficacy, as well as with psychological health. Moreover, three burnout dimensions were found to be significantly linked to psychological health in the way we had predicted. Regression analysis indicated the moderating role of resilience on psychological health in emotionally exhausting situations. We conclude that the psychological characteristic resilience moderated the effect of emotional exhaustion on the psychological health of the students. The practical implications of the results are discussed in order to introduce measures for the proper training of nursing students for professional practice; we also make several suggestions for future research in this field.     

A comparison of reading aloud,silent reading and follower reading. Which is best for comprehension? / Una comparación de lectura en voz alta,lectura en silencio y lectura de seguimiento. ¿Cuál es mejor para la comprensión?

When reading in the classroom, teachers may use different methods. We examined the impact of different reading conditions on comprehension. Reading aloud involved reading the text aloud for an audience. Silent reading required the students to read the text silently. Follower reading involved listening to another student read the text aloud while having the text available for individual reading. Thirty-six fifth- and sixth-grade students read texts under the three conditions and then took comprehension tests. The students performed equally well under reading aloud and silent reading. Follower reading resulted in worse comprehension. The data suggest that the follower readers focused on their individual reading, making an effort not to listen to the student reading out loud, which consumed cognitive resources. Since reading aloud in the classroom involves not only one loud reader but also a lot of follower readers, silent reading might be the smartest choice.