Eccentric loading and range of knee joint motion effects on performance enhancement in vertical jumping

The aim of the study was to determine the effects of variations in eccentric loading and knee joint range of motion on performance enhancement associated with the stretch-shortening cycle in vertical jumping. Seventeen male elite volleyball players performed three variations of the vertical jump which served as the research model: the squat jump (SJ), countermovement jump (CMJ) and drop jump from a height of 30 cm (DJ30). Knee joint angle (70 degrees and 90 degrees of flexion) at the commencement of the propulsive phase for each jump type was experimentally controlled, with the trunk kept as erect as possible. Force and motion data were recorded for each performance and used to compute a range of kinematic and kinetic variables, including hip, knee and ankle angles, angular velocities, work done, net joint moments and a number of temporal variables. The average of 12 trials for each participant was used in a series of repeated measures ANOVA's (jump xk nee, alpha=.05). From both knee joint angles, an increase in eccentric loading resulted in a significant increase in jump height (DJ30>CMJ>SJ; p<.05). These enhancements were significantly greater (p<.05) for 70 degrees in comparison to 90 degrees of knee flexion. From 70 degrees of knee flexion, these enhancements were due to significant increases in work done at all three joints; while from 90 degrees of knee flexion, only the hip and ankle joints appeared to contribute (p<.05). The amount of enhancement associated with employing the SSC in jumping is dependent upon the interaction of the magnitude of eccentric loading and the range of motion used.     

Conceptions of Research Methods Learning Among Psychology Undergraduates: A Q Methodology Study*

Abstract

A range of conceptions held about research methods learning have previously been identified. This study aimed to examine in-depth shared conceptions among undergraduate psychology students. Utilizing Q methodology, which links both quantitative and qualitative methodologies to uncover the subjective viewpoints that a group of individuals hold toward a particular domain, participants ranked statements reflecting different conceptions of research methods learning. Ranks were then factor analyzed and four distinct profiles of student conceptions were identified, labelled, and described in qualitative detail: research methods as integral to psychology, research methods as a digression from psychology, research methods as disconnected from psychology, and research methods as beneficial to psychology. Some of the perspectives displayed a clear understanding about the reasons for undertaking research and learning about research methods in psychology, whereas other standpoints saw research as being something that was difficult to relate to the practice of psychology. Findings are considered in terms of how some conceptions appear to be more beneficial or problematic to hold than others and recommendations are made to educators about how they could support students to change their views.     

War and poverty

Philosophical Studies - Because the poorest people tend to die from easily preventable diseases, addressing poverty is a relatively cheap way to save lives. War, by contrast, is extremely...     

Assessing metacognitive skills in waking and sleep: a psychometric analysis of the Metacognitive, Affective, Cognitive Experience (MACE) questionnaire

The Metacognitive, Affective, Cognitive Experience (MACE) questionnaire was designed to assess metacognition across sleep and waking (Kahan & LaBerge, 1996). The present research evaluates the psychometric properties of the MACE. Data from two recent studies (N=185) were used to assess the inter-item consistency, test-retest reliability, and factorial, convergent, and discriminant validity of the MACE. Results show that the MACE is a reliable measure with good construct validity. Exploratory factor analyses revealed one self-regulation and two monitoring factors. One monitoring factor emphasized monitoring internal conditions; the other emphasized monitoring external conditions. This factor structure is consistent with the Metacognitive Model (Nelson & Narens, 1990). Tests of convergent and discriminant validity suggest that the MACE is assessing metacognition and is appropriately related to similar constructs such as mindfulness and self-consciousness. The implication of these findings as well as suggestions for research and clinical applications of the MACE are discussed.     

Personal Genomic Testing as Part of the Complete Breast Cancer Risk Assessment: A Case Report

Patient access and utilization of personal genomic testing is becoming increasingly common. We present a case of a patient's personal genomic screening results leading to early detection of infiltrating breast ductal cell carcinoma via MRI scan. This case exemplifies the successful integration of personal genomic testing into the primary care setting, with the guidance and support of genetic counseling services. We discuss the scientific basis of the patient's genome scan results and risk assessment, and how this informed her decision-making and subsequent screening. We also expound upon the role of personal genomic testing as compared to other screening tests in the complete breast cancer risk assessment.     

What is a reason to act?

Argues for a conception of reasons as premises of practical reasoning. This conception is applied to questions about ignorance, advice, enabling conditions, “ought,” and evidence.