The role of upper torso and pelvis rotation in driving performance during the golf swing

While the role of the upper torso and pelvis in driving performance is anecdotally appreciated by golf instructors, their actual biomechanical role is unclear. The aims of this study were to describe upper torso and pelvis rotation and velocity during the golf swing and determine their role in ball velocity. One hundred recreational golfers underwent a biomechanical golf swing analysis using their own driver. Upper torso and pelvic rotation and velocity, and torso-pelvic separation and velocity, were measured for each swing. Ball velocity was assessed with a golf launch monitor. Group differences (groups based on ball velocity) and moderate relationships (r > or = 0.50; P < 0.001) were observed between an increase in ball velocity and the following variables: increased torso-pelvic separation at the top of the swing, maximum torso-pelvic separation, maximum upper torso rotation velocity, upper torso rotational velocity at lead arm parallel and last 40 ms before impact, maximum torso-pelvic separation velocity and torso-pelvic separation velocity at both lead arm parallel and at the last 40 ms before impact. Torso-pelvic separation contributes to greater upper torso rotation velocity and torso-pelvic separation velocity during the downswing, ultimately contributing to greater ball velocity. Golf instructors can consider increasing ball velocity by maximizing separation between the upper torso and pelvis at the top of and initiation of the downswing.     

A comparison of WISC-R and stanford-binet intelligence scale classifications of developmentally disabled children

WISC-Rs and Stanford-Binets were administered to 50 children with developmental disabilities referred for comprehensive evaluations. Although the two IQs correlated highly and significantly, it was found that 54% of the children received different classifications using the two instruments. Thus, testers should be aware that different classifications of intellectual level may be derived for the same child depending upon which test is used.     

Assessment of attention in school children: teachers' ratings related to tests of attention

The paper provides (1) a teacher-administered rating instrument for inattention without confounding the rating with hyperactivity and conduct disorder, and (2) evidence that the ratings correlate with the scores obtained from cognitive tests of attention. In Study I, the first objective was to investigate the construct validity and the inter-rater reliability of the Attention Checklist (ACL) by factor analysing the teacher ratings of 110 Grade 4 children, obtained by using the ACL. The second objective was to investigate the predictive validity of the ACL by examining the relationship between the scores obtained for the participants from teachers' ratings using the ACL and the scores obtained by participants in the lab-type attention tests. The results of factor analysis showed that a single factor labelled ‘inattention’ underlies the 12 items in the ACL. Examining the differences in performance on attention tests, the ‘low attention’ children as rated by the teachers on the ACL scored lower than the ‘high attention’ children on the objective tests of attention. These findings were replicated in Study II, which was conducted to test further the construct validity and predictive validity of the ACL. This time, only those two tests (Auditory Attention and Visual Attention) that had shown relatively poor discrimination between the high and low attention groups in Study I were, again, administered to another cohort of 97 Grade 4 children, as it was our intention to further challenge the reliability of the ACL. Overall, the results of both studies suggest that comprehensive assessment of attention skills should include both ACL and objective measures of selective attention.     

Making Sense in Education: Pretense (Including No Child Left Behind) and Realities in Rhetoric and Policy About Schools and Schooling

One wrong assumption about reality is sufficient to ensure the failure of education policy. For a variety of reasons, too many people have ignored realities in policies such as the No Child Left Behind Act. Individuals who are serious about reforming or improving education, general or special, must confront realities in at least the following areas: measurement, statistical distributions, measurement error, labels, special services, teacher responsibilities, and teacher training. Enacting or supporting education policy that is known to be seriously flawed is unacceptable and tantamount to the criminal conduct of someone who markets goods with known safety defects or harmful effects or of someone who ignores critical realities in the conduct of business.     

Politics,Civil Rights,and Disproportional Identification of Students with Emotional and Behavioral Disorders

The civil rights movements involving skin tone, gender or gender orientation, disability, and other physiognomic features remain important in securing the legal rights of individuals to equal treatment and equal opportunities regardless of their personal characteristics of color, origin, gender, and so on. Unfortunately, these welcome civil rights movements have led to a misunderstanding of unfairness in another group of individuals whose rights and opportunities have often been abridged—students with disabilities. Individual rights and opportunities must be insured, but doing so requires the discrimination of differences among differences. That is, not all differences require the same remedy to insure equal rights and opportunities. Misunderstanding of differences and their implications have led to political concerns about disproportional representation, particularly of students with emotional or behavioral disorders, which place unwarranted constraints on special education services.     

Differences in activation patterns between eccentric and concentric quadriceps contractions.

Previous studies analysing electromyograms (EMGs) from indwelling electrodes have indicated that fast-twitch motor units are selectively recruited for low-intensity eccentric contractions. The aim of this study was to compare the frequency content of surface EMGs from quadriceps muscles during eccentric and concentric contractions at various contraction intensities. Electromyograms were recorded from the rectus femoris, vastus lateralis and vastus medialis muscles of 10 men during isokinetic (1.05 rad x s(-1)) eccentric and concentric knee extension contractions at 25%, 50%, 75% and 100% of maximal voluntary contraction (MVC) for each contraction mode. Additionally, isometric contractions (70 degrees) were performed at each intensity. The mean frequency and root mean square (RMS) of the surface EMG were computed. Mean frequency was higher for eccentric than concentric contractions at 25% (P < 0.01), 50% (P < 0.01) and 75% (P < 0.05) but not at 100% MVC. It increased with increasing contraction intensity for isometric (P < 0.001) and concentric (P < 0.01) contractions but not for eccentric contractions (P = 0.27). The EMG amplitude (RMS) increased with increasing contraction intensity similarly in each contraction mode (P < 0.0001). Higher mean frequencies for eccentric than concentric contractions at submaximal contraction intensities is consistent with more fast-twitch motor units being active during eccentric contractions.