Greater lower limb flexion in gymnastic landings is associated with reduced landing force: a repeated measures study

High impact forces during gymnastic landings are thought to contribute to the high rate of injuries. Lower limb joint flexion is currently limited within gymnastic rules, yet might be an avenue for reduced force absorption. This study investigated whether lower limb flexion during three gymnastic landings was related to force. Differences between landings were also explored. Twenty-one elite women's artistic gymnasts performed three common gymnastic techniques: drop landing (DL), front and back somersaults. Ankle, knee, and hip angles, and vertical ground reaction force [(vGRF) magnitude and time to peak], were measured using three-dimensional motion analysis and force platform. The DL had significantly smaller peak vGRF, greater time to peak vGRF and larger lower limb flexion ranges than landing from either somersault. Peak vGRF and time to peak vGRF were inversely related. Peak vGRF was significantly reduced in gymnasts who landed with greater hip flexion, and time to peak was significantly increased with increasing ankle, knee, and hip flexion. Increased range of lower limb flexion should be encouraged during gymnastic landings to increase time to peak vGRF and reduce high impact force. For this purpose, judging criteria limitations on lower limb flexion should be reconsidered.     

Alterations in Body Size and Composition Consequent to Astro-Trimmer and Slim-Skins Training Programs

Tennis is an activity requiring both endurance and anaerobic components, which could have immunosuppressive effects postexercise.

Purpose

The purpose of this investigation was to determine the effect of a simulated tennis match on apoptotic and migratory markers on lymphocyte subsets.

Method

Male high school (n = 5) and college (n = 3) tennis players (M _age = 18.9 ± 3.3 years) completed 10 sets of a tennis protocol including serves, forehand strokes, and backhand groundstrokes with 1-min rest periods between sets. Apoptosis antigen 1 receptor (CD95) and chemokine receptor fractalkine (CX₃CR1) expression was analyzed on helper T lymphocytes (CD4+), cytotoxic T lymphocytes (CD8+), and B lymphocytes (CD19+) twice, at resting baseline and immediately after all 10 sets of the tennis protocol.

Results

An increase was observed in each lymphocyte subtype (p < .02, effect size = .41), and comparison of absolute changes revealed increases in CD4+/CD95+, CD8+/CD95+, and CD8+/CX₃CR1 lymphocytes following the tennis protocol (p < .01, effect size = .43), but not in CD19+ cells.

Conclusions

A simulated tennis match has adequate intensity to induce immune modulations in terms of increased cell death and cellular migration in T lymphocyte subsets. Lymphocytopenia following tennis play is influenced by both apoptotic and migratory mechanisms.     

Transforming engagement: a case study of building intrinsic motivation in a child with autism

This longitudinal case study of a 10‐year‐old girl with autism and severe communication impairment measures the impact of the MORE (Means, Opportunities, Reasons and Expectations) approach to enhancing engagement and communication. Through detailed observation of video data over a period of 28 months, engagement behaviours including interaction with adults and following adult directions increased, while resistant behaviours such as kicking, hitting and pushing adults away decreased. Fluctuation between different ‘states’ demonstrated that the frequency and duration of engagement was influenced by the MORE approach and an emphasis on developing intrinsic motivation. In order to enable further efficacy research, core features of the intervention and the changes in engagement over time are described.     

Relating deaf students' reading and language scores at college entry to their degree completion rates

Graduation patterns were examined for 905 deaf students (1990-1998) at the National Technical Institute for the Deaf. Students with higher reading and language skills had the best overall graduation percentage. Comparison of recipients of different degrees--bachelor of science (BS) versus fine arts (BFA); associate of applied science (AAS) versus occupational studies (AOS)--showed 92% of BS and 82% of AAS graduates reading at the 9th-grade level or above, versus 65% of BFA and 47% of AOS graduates. Interestingly, 80% of non-degree-earning students read at the 9th-12th grade levels; in absolute terms, they outnumbered graduates with similar reading skills in the AAS and BFA programs combined, and in the BS program. This indicates a need for improved counseling, placement, and retention strategies. Students performed similarly across degree categories, regardless of curriculum requirements and difficulty. Only non-degree-earning students had significantly lower grade averages.     

Scientific communication – on the brink of the next evolution?

Key points

• Publishing is fixated on the format of the scholarly article, and this is stifling innovation.
• Content should be presented in a way that adapts dynamically to the reader's needs.
• A lot of interdisciplinary research is needed to transform reading, writing, and publishing processes.

     

Teachers’ potential to promote students’ deeper learning in whole-class teaching: An observation study in Norwegian classrooms

Journal of Educational Change - Teachers worldwide are challenged to adjust their teaching to meet students’ needs for deeper learning. The lack of mutual understanding among researchers,...     

Respiration and Cognitive Synergy: Circulation in and Between Scientific Research Spheres

This article explores the crucial moments of scientists’ research activities when they decide to shift to a radical new domain or to perpetuate a project. We introduce what we have called the “respiration model” which describes and analyses key cognitive components which occur in this complex process. Respiration either privileges epistemic expectations which are rooted in socio-cognitive metrics of “concentration” or in a functionality-multiple horizon context which we refer to as “extension”. The respiration model accords particular attention to the elements curiosity and synergy in science.