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61.
The present study aimed to investigate pre-sleep behaviours (including evening electronic device use) and sleep quantity in well-trained athletes. Seventy well-trained athletes (44 females, 26 males) aged 21 ± 4 y from a range of team and individual sports were asked to complete an online sleep diary for 7 days. The sleep diary included questions about pre-sleep behaviours (e.g. napping, caffeine intake), electronic device use in the 2 h prior to bedtime (e.g. type of device and duration of use) and sleep (e.g. time in bed, sleep onset latency). On average, athletes spent 8:20 ± 1:21 h in bed each night. Associations between age, time in bed and sleepiness suggested that younger athletes spent more time in bed (= -0.05, p = 0.001) but felt sleepier (r = -0.32, p < 0.01) than older athletes. On average, athletes mostly used electronic devices for 0–30 min prior to sleep. The use of multiple devices in the evening was associated with more perceived difficulty in falling asleep (= 0.22, p = 0.03), but no associations existed with other sleep variables. In summary, younger athletes may require later start times or improved sleep quality to resolve excessive sleepiness.  相似文献   
62.
The purpose of this study was to compare the validity and reliability of three short physical activity self-report instruments to determine their potential for use with university student populations. The participants (N = 155; 44.5% male; 22.9 ± 5.13 years) wore an accelerometer for 9 consecutive days and completed a single-item measure, the a brief two item measure and the International Physical Activity Questionnaire—Short Form questionnaires on day 1 and 9. Correlations between self-reported and accelerometer derived moderate-to-vigorous physical activity levels were moderate for the International Physical Activity Questionnaire—Short Form, while poor for the single-item measure and the a brief two item measure. The agreement level was high with the International Physical Activity Questionnaire—Short Form (77.4%) and moderate for both the single-item measure (45.2 %) and a brief two item measure (44.5 %). The intraclass correlations between the two administrations were moderate to strong across all measures (0.52–0.70) in 133 participants. The International Physical Activity Questionnaire—Short Form is the most suitable of these three self-report instruments for use with this population due to higher correlations and levels of agreement with accelerometry.  相似文献   
63.
This study compared markers of muscle damage and inflammation elevated by a matched-intensity interval running session on soft sand and grass surfaces. In a counterbalanced, repeated-measures and crossover design, 10 well-trained female athletes completed 2 interval-based running sessions 1 week apart on either a grass or a sand surface. Exercise heart rate (HR) was fixed at 83–88% of HR maximum. Venous blood samples were collected pre-, post- and 24?h post-exercise, and analysed for myoglobin (Mb) and C-reactive protein (CRP). Perceptual ratings of exertion (RPE) and muscle soreness (DOMS) were recorded immediately post- and 24?h post-exercise. A significant time effect showed that Mb increased from pre- to post-exercise on grass (p?=?.008) but not on sand (p?=?.611). Furthermore, there was a greater relative increase in Mb on grass compared with that on sand (p?=?.026). No differences in CRP were reported between surfaces (p?>?.05). The HR, RPE and DOMS scores were not significantly different between conditions (p > .05). These results suggest that in response to a matched-intensity exercise bout, markers of post-exercise muscle damage may be reduced by running on softer ground surfaces. Such training strategy may be used to minimize musculoskeletal strain while still incurring an equivalent cardiovascular training stimulus.  相似文献   
64.
With the rise of microfluidics for the past decade, there has come an ever more pressing need for a low-cost and rapid prototyping technology, especially for research and education purposes. In this article, we report a rapid prototyping process of chromed masks for various microfluidic applications. The process takes place out of a clean room, uses a commercially available video-projector, and can be completed in less than half an hour. We quantify the ranges of fields of view and of resolutions accessible through this video-projection system and report the fabrication of critical microfluidic components (junctions, straight channels, and curved channels). To exemplify the process, three common devices are produced using this method: a droplet generation device, a gradient generation device, and a neuro-engineering oriented device. The neuro-engineering oriented device is a compartmentalized microfluidic chip, and therefore, required the production and the precise alignment of two different masks.  相似文献   
65.
Editorial     
B. Sury 《Resonance》2017,22(5):431-432
  相似文献   
66.
Prospective application of serum cytokines, lipopolysaccharide (LPS), and heat shock proteins (eHSPs) requires reliable measurement of these biomarkers that can signify exercise-induced heat stress in hot conditions. To accomplish this, both short-term (7 day) reliability (at rest, n = 12) and the acute responsiveness of each biomarker to exercise in the heat (pre and post 60-min cycling, 34.5°C and 70% RH, n = 20) were evaluated. Serum was analysed for the concentration of C-reactive protein (CRP), interleukin-6 (IL-6), heat shock protein 72 (eHSP72), immunoglobulin M (IgM) and LPS. Test–retest reliability was determined as the coefficient of variation (CV). Biomarkers with the least short-term within-participant variation were IL-6 (19%, ±20%; CV, ±95% confidence limits (CL)) and LPS (23%, ±13%). Greater variability was observed for IgM, eHSP72 and CRP (CV range 28–38%). IL-6 exhibited the largest increase in response to acute exercise (95%, ±11%, P = < 0.001) and although CRP had a modest CV (12%, ±7%), it increased substantially post-exercise (P = 0.02, ES; 0.78). In contrast, eHSP72 and LPS exhibited trivial changes post-exercise. It appears variation of common inflammatory markers after exercise in the heat is not always discernible from short-term (weekly) variation.  相似文献   
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69.
This article describes a study that aimed to answer the following question: ‘Will a programme of professional development in the area of special and inclusive education be effective in achieving attitudinal shift in teachers?’ Forty‐eight teachers who were enrolled on a Master's programme in Special and Inclusive Education were surveyed via a questionnaire at the beginning and end of a ten‐week introductory module. The results indicated overall attitudinal shift and attitudinal shift for four categories of inclusion to suggest more positive attitudes at the end of the module, compared with at the beginning. The implications for providers of pre‐ and in‐service education and training courses for teachers are discussed.  相似文献   
70.
ABSTRACT

The aim of the present study was to investigate the existence of a relative age effect (RAE) on physical fitness of preschoolers. Anthropometry and physical fitness were assessed in 3147 children (3–5 years old) using the PREFIT battery. Based on the birth year, participants were divided into 3year groups (3-, 4- and 5-years). Within each year group, 4quarter groups were created: quarter 1, preschoolers born from January to March; quarter 2, from April to June; quarter 3, from July to September; quarter 4, from October to December. The MANCOVA analysis revealed a main effect of year group (Wilks’ λ = 0.383; F10,5996 = 369.64; p < 0.001, ηp 2 = 0.381) and of quarter (Wilks’ λ = 0.874; F15,8276.6 = 27.67; p < 0.001; ηp 2 = 0.044) over the whole battery of tests. To the best of our knowledge, this is the first study to report the existence of RAE at the preschool stage. In general, performance improved as the relative age increased (i.e., those born in quarter 1 performed better than those in the other quarters). Individualization strategies should be addressed within the same academic year not only in elementary or secondary years but also in preschoolers.  相似文献   
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