Individual pathways in the development of forceful throwing

Halverson, Roberton, and Langendorfer (1982) reported the development of children ages 6-13 years filmed longitudinally performing the forceful overarm throw. These authors described the children's progress through developmental sequences for trunk, humerus, and forearm actions; however, they did not study developmental relationships ("profiles") across these components. This paper reports how the profiles changed in the same children across trials within filming sessions and over time. The data revealed both common and individual developmental pathways. The frequencies of some pathways were not chance occurrences (p < or = .01), suggesting that within-person constraints eliminated certain movement relationships while encouraging others. The authors hypothesize that the kinematics of trunk rotation may serve as a control parameter for pattern change.     

Comparing the pre- and post-impact ball and racquet kinematics of elite tennis players' first and second serves: a preliminary study

The aim of this study was to compare the pre- and post-impact three-dimensional kinematics of the ball and racquet during first and second serves performed by elite tennis players. Data were collected from four male and four female right-handed professional players during competition using two high-speed cameras (200 Hz). For each player, one first serve and one second serve from the 'deuce' or right service court that landed within the specified target area were analysed. To test for significant differences between the first and second serves, Wilcoxon tests (P < or = 0.05) were performed on selected parameters. The results indicate that the ball travelled forward and to the left during the flight phase of the toss in all but one trial. The average pre-impact ball forward location for the first serve was significantly more in front and had a higher associated forward ball velocity than the corresponding values for the second serve. On average, the decrease in post-impact ball speed from the first to the second serve was 24.1%. No significant differences between the first and second serves were found in the pre-impact racquet head speed and orientation, which was represented as a unit vector perpendicular to the racquet face. The major adjustments made by the players when going from the first to second serve were a decrease in pre-impact ball forward location (P < or = 0.01) and an increase in the pre-impact racquet vertical and lateral velocities (both P < or = 0.05). This implies that the players tossed the ball closer to the body and imparted topspin and sidespin on the ball by changing the racquet vertical and lateral velocities when going from the first to the second serve.     

Physical activity,physiological, and psychomotor performance: a study of variously active older adult men

This research examined varying levels of physical activity and psychomotor and physiological function in variously active older men. Very active moderately active, and low active participants were tested on simple (SRT) and choice reaction time (CRT), coincidence-anticipation timing (CAT), and VO2max. No significant differences for age or height were found, although percentage of fat, and weight were statistically different. Active groups were leaner and lighter. VO2max was significantly different between groups, as physically active groups yielded geater values. SRT and CAT also yielded significantly different results with more active participants showing better performance. No between-groups significant differences resulted for CRT. Generally, increased levels of physical activity were related to superior physiological outcomes and improved psychomotor peformance.     

Chronic flexibility gains: effect of isometric contraction duration during proprioceptive neuromuscular facilitation stretching techniques

The aim of this study was to assess the effect of to isometic contraction durations during propiceptive neuromuscular facilitation stretching on gains inflexion at the hip. Forty-three women (M age = 20.0 years, SD = 1.3) were assigned to one of three groups: 5-s isometric contraction (5-IC), 10-IC, and control. Flexibility was assessed at baseline and Weeks 3 and 6. Analysis of covariance, controlling for pretest differences, showed a significant interaction, F(2, 33) = 44.1, p < .001. Flexibility was significant lower in the control group relative to the 5-IC and 10-IC groups and in the 5-IC group relative to the 10-IC group at 3 and 6 weeks (3 weeks = 101.2 +/- 1.4 degrees, 114.3 +/- 1.5 degrees, 120.5 +/- 1.3 degrees; 6 weeks = 103.0 +/- 1.4 degrees, 126.1 +/- 1.6 degrees, 133.3 +/- 1.4 degrees for control, 5-IC and 10-IC groups, respectively). A longer contraction time led to greater increases in flexibility.     

In pursuit of empowerment: Sensei Nellie Kleinsmidt, race and gender challenges in South Africa

This chapter traces the way in which Nellie Kleinsmidt, known as the grandmother of karate in Africa, has negotiated discriminatory practices and overcome race and gender-related struggles, including the struggle to free the female body, in pursuit of empowerment. It explores her expectations and the constraints and frustrations she experienced, as well as the many contributions she has made to women's karate in South Africa. Nellie Kleinsmidt's karate career, which began in 1965, coincided with the early developments of South African karate. As a woman of colour her life and karate career were significantly shaped by apartheid legislation. It divided the country into areas of occupancy and residency according to race and was designed to prevent contact between the people of the government defined race groups. Black karate-kas were prohibited by law from practising karate in white designated areas. Lack of facilities and qualified instructors in areas allocated to Kleinsmidt's race group meant that she received very little formal karate instruction between 1966 and 1973. Soon after, she met Johan Roux, a white male. He was to become her chief karate instructor and life-long companion. They defied the apartheid legislation and in 1978 set up home together. They organized defiance campaigns, resisting the pressures from government to close their dojo because of its non-racial policies. Freeing her body at the broader political level involved the abolition of the race categories and all other apartheid legislation which impacted on her life choices and experiences. Initially this struggle and that of freeing her body occurred simultaneously. In her ongoing struggle against gender discrimination in the sport, it was in karate that Nellie Kleinsmidt could strive for the personal empowerment she sought. She could however not translate this into freedom in South African society itself. The impact of apartheid legislation together with the imposition of a sports moratorium by the South African Council on Sports (SACOS), hindered the growth of Nellie Kleinsmidt's karate career, yet she managed to obtain her sixth Dan Black Belt in 1998. This was a remarkable achievement given the constraints she had to overcome. In karate, Kleinsmidt was often viewed as a female first. The problem of female access is exacerbated by the overwhelming number of male instructors perpetuating the notion that the martial arts are inherently male sports. Accessing the various levels of karate has involved claiming physical and symbolic space on the dojo floor as well as involvement in the decision-making arenas of karate. In 1992 with the unification of karate in South Africa, Sensei Nellie began to extend her involvement with the refereeing arena and jointly established a Women's Karate Forum in her province. She has subsequently become a South African national referee and has earned the status of continental judge with the Union of African Karate Federation (UFAK). Nellie Kleinsmidt is the first and only woman of colour to have been appointed to the Referee's Board of South Africa and the only woman of colour in Africa to have obtained a sixth Dan Black belt.     

Visions of a cure. Visualization, clinical trials, and controversies in cardiac therapeutics, 1968-1998

In the early 1970s physicians engaged in fierce debates over the most appropriate method of evaluating the efficacy of coronary artery bypass grafting (CABG). With millions of patients and billions of dollars at stake, CABG sparked fierce controversy. Skeptics demanded that randomized controlled trials (RCTs) be performed, while enthusiasts argued that they already had visual proof of CABG's efficacy. When RCTs appeared, they did not settle the controversy. Participants simply reasserted their preconceptions, defending a trial's strengths or exploiting its flaws. The debate centered on standards of knowledge for the evaluation of therapeutic efficacy. Specifically, cardiologists and cardiac surgeons struggled to assess the relevance of different measures of therapeutic success: physiological or clinical, visual or statistical. Many factors contributed to participants' decisions, including disciplinary affiliation, traditions of research, personal experience with angiography, and assessments of the history of cardiac therapeutics. Physicians had to decide whether angiography provided a meaningful representation of the disease and its treatment or whether demonstrations of therapeutic success could come only from long-term statistical evaluation of mortality data.     

The initiation of distance learning at Thomas Jefferson University: the library as integral partner

In 1998 Thomas Jefferson University offered its first entirely online course. Librarians and library staff were integral in the development, support, evaluation, and refinement of this course. While staff members may have taken non-traditional roles in this effort, their roles generally fell within the broad guidelines of assisting University faculty with information and knowledge management. The development and support of distance course offerings will continue to be a focus at Scott Memorial Library.     

The effect of two different 18-week walking programmes on aerobic fitness, selected blood lipids and factor XIIa

Forty-nine previously sedentary or low active individuals aged 40-71 years were allocated to three groups. The long walking group participated in an 18-week walking programme which consisted of walks lasting 20-40 min; the repetitive short walking group completed walks of between 10 and 15 min, up to three times a day, with no less than 120 min between each walk; and the control group maintained their low level of activity. Both walking programmes began at a prescribed 60 min x week(-1), which increased steadily up to 200 min x week(-1) by week 12. During the study, the long walking group walked for an estimated 2514 min (139 min x week(-1)), expending an estimated 67.5 MJ (3.72 MJ x week(-1)) at an estimated 73% of their age-predicted maximum heart rate and 68% of their estimated VO2max. The repetitive short walking group walked for an estimated 2476 min (135 min x week(-1)), expending an estimated 58.5 MJ (3.17 MJ x week(-1)) at an estimated 71% of their age-predicted maximum heart rate and 65% of their estimated VO2max. The results showed a statistically significant reduction in heart rate during a standardized step test (pre- vs post-intervention) in both walking groups, indicating an improvement in aerobic fitness, although the control group showed a higher average heart rate during the post-intervention test, indicating reduced fitness. When compared with the male subjects pre-intervention, the females possessed more favourable levels of high-density lipoprotein (HDL) cholesterol (P< 0.001), apolipoprotein (apo) AI (P < 0.001) and ratios of total cholesterol:HDL cholesterol (P< 0.02) and low-density lipoprotein (LDL) cholesterol: HDL cholesterol (P< 0.02). Compared with the controls post-intervention, the walking groups showed no statistically significant changes in total cholesterol, LDL cholesterol, HDL cholesterol, apo AI, apo AII, apo B, or the ratios of total cholesterol: HDL cholesterol, LDL cholesterol: HDL cholesterol, apo AI: apo B or apo AI: apo AII (P > 0.05). Relative to the walking groups, factor XIIa increased in the control group (P < 0.05). We conclude that, although both walking programmes appeared to improve aerobic fitness, there was no evidence of improvements in the blood lipids or associated apolipoproteins of the walking groups. Further analysis indicated that this apparent lack of change may have been related to the subjects' relatively good pre-intervention blood lipid profiles, which restricted the potential for change. The implications of the observed changes in the coagulation/fibrinolytic factors remain unclear.