226 research outputs found
The Effect of Physical Activity on Cognitive Performance in an Italian Elementary School: Insights From a Pilot Study Using Structural Equation Modeling
When compared to the previous generations, younger generations have become sedentary on a global level. Physical activity positively contributes to human growth and development, causing, indeed, both physiological and psychological benefits. The aim of the current study was examining the relationship between physical activity and school achievement in a sample of 80 Italian elementary (viz. primary) school last year responding children (11.0 ± 0.3 years, 1.46 ± 0.09 m, 39.5 ± 7.9 kg). Such an aim was fulfilled by investigating eventual correlations between physical tests results and school marks and by disclosing eventual mutual relationships between socio-demographics, family context, lifestyle (including physical activity), and school performance information using a structural modeling approach. Children were assessed for lower/upper limbs muscle strength and running/agility performance. Pearson’s correlation between physical tests and school performance was studied. We found that agility correlated with English, Italian, mathematics, music, and sport marks, whereas jump correlated with English, mathematics, sport, and technologies marks. Sprint correlated with mathematics, sport, and technologies marks. All correlation coefficients were moderate, except for correlations between sport marks and physical tests (strong correlation). From the structural model, we found that socio-demographics and lifestyle significantly impacted on school achievement. In particular, lifestyle was found to fully moderate the impact of the family context on school achievement. Schools and households represent important settings for improving children physical and psychological-cognitive health and status, offering physical activities opportunities
Braid Groups on Triangulated Surfaces and Singular Homology
Let denote the closed orientable surface of genus and fix an
arbitrary simplicial triangulation of . We construct and study a
natural surjective group homomorphism from the surface braid group on
strands on to the first singular homology group of with
integral coefficients. In particular, we show that the kernel of this
homomorphism is generated by canonical braids which arise from the
triangulation of . This provides a simple description of natural
subgroups of surface braid groups which are closely tied to the homology groups
of the surfaces
The influence of burpee on endurance and short-term memory of adolescents
Aim-The purpose of this study was to assess the effect of the Burpee exercise on the endurance and short-term memory of adolescents aged 15-16 years. Methods-The experiment was performed in a coeducational school in Kirov (Russia). The four-month study involved 52 adolescents of both genders. During the study period, 30 physical education lessons were held in each class. Adolescents from the control group were involved in a typical program (also aimed at improving endurance), and adolescents from the experimental group additionally performed the Burpee exercise. Endurance in adolescents was assessed by means of an "all-out" Running 2000 m test, and short-term memory was assessed by means of the Jacobs test (tests were performed before and after the programs). Results-An analysis of variance revealed an interaction effect (F = 28.733, ηp2 = 0.578 and p < 0.001, and F = 104.353, ηp2 = 0.676 and p < 0.001 for the Running 2000 m test and the Jacobs test, respectively). The control group improved by 1.9% (p > 0.05) in the Running 2000 m and by 5.5% (p > 0.05) in the Jacobs test. In the experimental group, both improved significantly by 8.6% (p < 0.05) in the Running 2000 m test and by 26.0% (p < 0.05) in the Jacobs test. Conclusion-The Burpee exercise could be included in physical education classes to improve endurance and short-term memory in 15-16-year-old
Did You See?
The Winter 1965 issue of Reading Research Quarterly published by the International Reading Association? It is devoted to a summary of investigations relating to reading compiled by Helen M. Robinson, Samuel Weintraub, and Helen K. Smith of the University of Chicago. In this review, the research is classified under six major topics: 1) Summaries of Specific Aspects of Reading Research; 2) Teacher Preparation and Practice; 3) The Sociology of Reading; 4) The Physiology and Psychology of Reading; 5) The Teaching of Reading; and 6) The Reading of Atypical Learners
Electromyographic analysis of riding posture during the bicycling start moment
Professional cyclists often adopt a competition-start standing posture, which has been shown to improve performance. The biomechanical basis of this is unclear, and might be due to a greater mechanical advantage or increased key muscle activity. Previous observations in steady state cycling showed greater activation of the tibialis anterior, erector spinae, and biceps brachii when adopting a standing vs. seated-riding posture. Little is known regarding the effect of riding posture on activation during a standing start. Eleven cyclists performed standing starts in seated and standing-postures using stationary-cycle and on the track. Electromyography of the gastrocnemius medialis, tibialis anterior, erector spinae, and biceps brachii was recorded during first and subsequent pedal strokes. Results showed that the gastrocnemius medialis did not modify activity. The tibialis anterior, erector spinae, and biceps brachii activity was increased during the standing posture compared to seated, only during the first pedal stroke. These increased activation intensities were accompanied by a corresponding 10% increase in bike speed during the first 5 meters following a standing start in the standing posture compared to the seated one. Adopting a standing posture during a standing start improves performance through greater initial acceleration
Effect of three technical arms swings on the elevation of the center of mass during a standing back somersault
Arms swing during standing back somersaults relates to three different “gymnastics schools”, each is considered “optimal” by its adepts. In the three cases, technical performance, elevation and safety differ. Therefore, the aim of this study was to compare the mechanical variables of three different arms swing techniques in the performance of a standing back tucked somersault. Five high-level male gymnasts (age: 23.17±1.61 yrs; body height: 1.65±0.05 m; body mass: 56.80±7.66 kg) randomly performed standing somersaults under three conditions, each following a different arms’ swing technical angle (270°, 180° and 90°). A force plate synchronized with a three dimensional movement analysis system was used to collect kinetic and kinematic data. Significant differences were observed between somersaults’ performance. The back somersault performed with 270° arms swing showed the best vertical displacement (up to 13.73%), while the back somersaults performed with 180° arms swing showed a decrease in power (up to 22.20%). The back somersault with 90° arms swing showed the highest force (up to 19.46%). Considering that the higher elevation of the centre of mass during the flight phase would allow best performance and lower the risk of falls, this study demonstrated that optimal arms’ swing technique prior to back tucked somersault was 270°
Editorial: Structural and mechanistic determinants of endurance performance
[no abstract available
Corrigendum: Leg Press vs. Smith Machine: Quadriceps Activation and Overall Perceived Effort Profiles
Selected components of physical fitness in rhythmic and artistic youth gymnast
Abstract
Purpose
Rhythmic (RG) and artistic gymnastics (AG) are very popular female sports. These two disciplines share some common points but, at the same time, they display some relevant differences in terms of physical and technical characteristics. The aim of this study was as follows: (1) to clarify how gymnastic training background over the years could lead to the development and motor learning of the motor skills and (2) to highlight differences of conditional skills achieved by RG and AG athletes.
Methods
For these aims, 45 athletes were selected, belonging to three balanced groups: promotional (PG, n = 15), RG (n = 15), and AG (n = 15). Participants were tested for joints mobility, balance, explosive strength, speed, and endurance tests.
Results
Statistical analysis showed a good test–retest reliability of the measurements (ICC > 0.870) and some significant differences between PG, RG, and AG. RG showed higher values in joint mobility tests (coxo-femoral mobility, 166.7 ± 6.3°; sit and reach, 20.5 ± 1.9 cm; and scapulo-humeral mobility, 45.5 ± 4.4 cm) with respect to AG, while AG showed higher values in endurance (1626.7 ± 7.4 m), balance (4.33 ± 1.35 n/60 s), and explosive strength (164.1 ± 11.6 cm) compared to RG (p < 0.05).
Conclusion
RG and AG seem to be effective in enhancing different and sport-specific physical fitness and conditioning. RG enables, indeed, to develop more joints mobility whereas AG improves more strength, balance, and endurance. However, given the small sample size employed, these results should be replicated by further studies utilizing larger samples
Effects of acute and chronic exercise on immunological parameters in the elderly aged: can physical activity counteract the effects of aging?
Immunosenescence is characterized by deterioration of the immune system caused by aging which induces changes to innate and adaptive immunity. Immunosenescence affects function and phenotype of immune cells, such as expression and function of receptors for immune cells which contributes to loss of immune function (chemotaxis, intracellular killing). Moreover, these alterations decrease the response to pathogens, which leads to several age-related diseases including cardiovascular disease, Alzheimer's disease, and diabetes in older individuals. Furthermore, increased risk of autoimmune disease and chronic infection is increased with an aging immune system, which is characterized by a pro-inflammatory environment, ultimately leading to accelerated biological aging. During the last century, sedentarism rose dramatically, with a concomitant increase in certain type of cancers (such as breast cancer, colon, or prostate cancer), and autoimmune disease. Numerous studies on physical activity and immunity, with focus on special populations (i.e., people with diabetes, HIV patients) demonstrate that chronic exercise enhances immunity. However, the majority of previous work has focused on either a pathological population or healthy young adults whilst research in elderly populations is scarce. Research conducted to date has primarily focused on aerobic and resistance exercise training and its effect on immunity. This review focuses on the potential for exercise training to affect the aging immune system. The concept is that some lifestyle strategies such as high-intensity exercise training may prevent disease through the attenuation of immunosenescence. In this context, we take a top-down approach and review the effect of exercise and training on immunological parameters in elderly at rest and during exercise in humans, and how they respond to different modes of training. We highlight the impact of these different exercise modes on immunological parameters, such as cytokine and lymphocyte concentration in elderly individuals
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