Gender differences among sagittal plane knee kinematic and ground reaction force characteristics during a rapid sprint and cut maneuver

Women are more prone to anterior cruciate ligament (ACL) injury during cutting sports than men. The purpose of this study was to examine knee kinematic and ground reaction forces (GRF) differences between genders during cutting. Male and female athletes performed cutting trials while force platform and video data were recorded (180 Hz). Differences (p < . 05) were observed between groups for knee flexion at contact and GRF at maximum knee flexion. Women averaged 5.8 degrees less flexion at contact and 1.0 N. (kg x m x s(-1))(-1) greater GRF at maximum flexion. Knee range of motion and peak GRF variables were not significantly different, but women had greater values. Women exhibited technique characteristics believed to increase ACL injury risk, but men exhibiting similar characteristics were also observed and could also be at risk.     

Maximal-intensity isometric and dynamic exercise performance after eccentric muscle actions

A well-documented observation after eccentric exercise is a reduction in maximal voluntary force. However, little is known about the ability to maintain maximal isometric force or generate and maintain dynamic peak power. These aspects of muscle function were studied in seven participants (5 males, 2 females). Knee extensor isometric strength and rate of fatigue were assessed by a sustained 60 s maximal voluntary contraction at 80 degrees and 40 degrees knee flexion, corresponding to an optimal and a shortened muscle length, respectively. Dynamic peak power and rate of fatigue were assessed during a 30 s Wingate cycle test. Plasma creatine kinase was measured from a fingertip blood sample. These variables were measured before, 1 h after and 1, 2, 3 and 7 days after 100 repetitions of the eccentric phase of the barbell squat exercise (10 sets x 10 reps at 80% concentric one-repetition maximum). Eccentric exercise resulted in elevations in creatine kinase activity above baseline (274+/-109 U x l(-1); mean +/- s(x)) after 1 h (506+/-116 U x l(-1), P < 0.05) and 1 day (808+/-117 U x l(-1), P < 0.05). Isometric strength was reduced (P < 0.05) for 7 days (35% at 1 h, 5% at day 7) and the rate of fatigue was lower (P < 0.05) for 3 days at 80 degrees and for 1 day at 40 degrees. Wingate peak power was reduced to a lesser extent (P < 0.05) than isometric strength at 1 h (13%) and, although the time course of recovery was equal, the two variables differed in their pattern of recovery. Eccentrically exercised muscle was characterized by an inability to generate high force and power, but an improved ability to maintain force and power. Such functional outcomes are consistent with the proposition that type II fibres are selectively recruited or damaged during eccentric exercise.     

REPORT OF BIBLICAL INSTRUCTORS CONFERENCE*

This article examines the psychoanalytic concepts of object-relations theorist Christopher Bollas, applying them to a view of the Bible as “transformational object.” Emphasizing the connection between psychological process and religious experience, this article suggests that each person's innate ability to choose and use objects is a key factor in their ability to appropriate the Bible for constructive use. By offering religious objects with psychological awareness, religious educators may come to appreciate that silence, empathy, and open-ended lesson plans are important incubators of transformation; and that aggression has a potentially positive role in the healthy development of worship communities.     

Stress sensitivity and reading performance in Spanish: A study with children

This paper investigates the relationship between ability to detect changes in prosody and reading performance in Spanish. Participants were children aged 7–8 years. Their tasks consisted of reading words, reading non‐words, stressing non‐words and reproducing sequences of two, three or four non‐words by pressing the corresponding keys on the computer keyboard. Non‐word sequences were constructed with minimal non‐word pairs differing in a single phoneme (/kúpi/ ‐ /kúti/) or in the stress pattern (/mípa/ ‐ /mipá/). Results showed that performance on phoneme contrast sequences (e.g. /kúpi/ ‐ /kúti/) predicted word reading. In contrast, performance on stress contrast sequences (e.g. /mípa/ ‐ /mipá/) predicted non‐word reading, but only when two‐non‐word sequences were analysed. This suggests that stress sensitivity may be one of the factors related to reading fluency as most errors at reading non‐words consisted of false starts and pauses between syllables. Results also showed that stress sensitivity (scored in two non‐word sequences) predicted stress assignment, and that knowledge of stress rules predicted both word and non‐word reading. This suggests that stress sensitivity may help in learning stress rules, and that knowledge of stress rules is relevant for reading.