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BackgroundAthletes tend to have better visuo-motor performance than do sedentary individuals. However, several basic visual-function and perceptual parameters remain unexplored to date. In this study, we investigated whether differences exist in visual function, performance, and processing between basketball players and individuals without a sport-involvement background.MethodsA total of 33 healthy men with no visual impairment or pathology were divided into 2 groups, depending on the involvement in sport (semi-professional basketball players and sedentary individuals). We tested their baseline heart-rate variability in the resting position apart from subjective questionnaires to determine their physical fitness level, and we checked their visual function, performance, and processing through an extended battery of optometric tests.ResultsThe 2 groups differed in resting heart-rate variability parameters (p < 0.001), confirming their dissimilarities in regular time practising sports per week. The basketball players showed a closer breakpoint and recovery nearpoint of convergence, a higher fusional-vergence rate, better discriminability halos, and better eye–hand coordination (all p values < 0.05).ConclusionThese results show evidence that athletes, basketball players in this case, exhibit better performance in several visual abilities in comparison to a group of individuals without sporting backgrounds, suggesting an improvement due to the systematic involvement of those skills during basketball practice.  相似文献   
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社会快速发展、生活日趋便捷背景下,医学生面临着生理和心理上的问题,且医学生由于专业特殊性,认知能力中记忆力的重要性被凸显出来。本文运用查阅文献资料、专家访谈、问卷调查、逻辑分析等研究方法,探究从运动处方角度出发的实验--"高强度间歇运动对医学生不同时长记忆力的影响"具有多方面重要性。同时建议医学院校应当跟据研究结果和实际情况,制定科学、合理的运动训练计划,为医学生生理和心理健康提供保障。  相似文献   
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运动作为防治疾病的一味"药",正迅速被越来越多的医生所认可,并走进了大众的日常生活。运动既然是"药",就不该是"多多益善",而应该是"量体裁衣"、个性化定制,也因此需要处方。文章旨在回顾运动处方过去和现在的发展与对未来发展需求的猜测,对这个方兴未艾的领域增进了解,并进行系统介绍。追溯运动处方的研究和发展历史,大致可以分为4个时期3个阶段,从认识到运动对健康的重要性到运动成为防病治病的良药以及运动处方的发展走过了近70年的历程。国外大量科学的研究(尤其是追踪研究)和数据是支持运动处方不断前进的基石。从运动处方科学发展中所学到的智慧将会对中国传统运动处方的建设、中国大众的健康促进作出积极贡献。  相似文献   
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Purpose: Brain-derived neurotrophic factor (BDNF) is well known for its potential to promote brain plasticity. It has been proposed that combining cognitive and physical exercise (CCPE) may have the potential to generate more synergistic benefits in cognitive function than either cognitive exercise (CE) or physical exercise (PE) alone. The purpose of this study was to examine acute responses of peripheral BDNF levels and cognitive performance to CE, PE, and CCPE.

Methods: Thirteen healthy adult men participated in four experimental sessions; a 30-min CE, a 30-min cycling PE at an intensity of 60% peak oxygen uptake, a 30-min CCPE at the same intensity as PE, and a 30-min session of complete rest. Plasma BDNF levels and cognitive performance were measured before and after each session.

Results: Both PE and CCPE significantly increased plasma BDNF levels (p?p?≥?.05), and there was no significant difference in peripheral BDNF levels between PE and CCPE (p?≥?.05). No session induced a significant change in cognitive performance (p?≥?.05).

Conclusions: Our study suggests that CE and PE have different responses of peripheral BDNF levels and that CCPE had no additional or synergistic effect on peripheral BDNF levels compared with PE alone. This study offers further insights into the potential mechanisms underlying the respective roles of CE, PE, and CCPE for peripheral BDNF levels and cognitive performance.  相似文献   
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ABSTRACT

The length of telomeres is an objective measure of biologic ageing. This study evaluated the extent minutes of walking per week are associated with leukocyte telomere length (LTL) in a random sample of 5,823 U.S. adults. The investigation was cross-sectional and data were obtained from the National Health and Nutrition Examination Survey (NHANES). LTL was measured by the quantitative polymerase chain reaction method. Walking minutes was calculated from walking frequency and duration measures. Results showed that for each year of chronological age, telomeres were 15.6 base pairs shorter (P < 0.0001). With walking minutes and LTL treated as continuous variables, the relationship was quadratic, not linear (F = 11.2, P = 0.0023). With walking time divided into three categories, adults who performed ≥ 150 minutes of walking per week had longer telomeres than those who did no regular walking, and those who did some, but less than the recommendation (F = 5.0, P = 0.0137). Regular walkers were estimated to have a biologic ageing advantage associated with 6.5–7.6 years less biologic ageing compared to non-walkers, after adjusting for covariates. Additional investigations designed to study causality and the mechanisms associated with the walking and LTL relationship are needed.  相似文献   
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The purpose of this study was to identify which averaging methods most accurately measures peak cardiorespiratory fitness (CRF) parameters [peak O2 uptake (VO2), peak O2pulse and peak respiratory exchange ratio (RER)] in a sample of healthy children and adolescents. In this cross-sectional multicenter study, we recruited 278 healthy children aged 12–17 years. We compared the mean peak value of three CRF parameters using the recommended averaging methods (30-second block average) with alternative averaging methods such as moving averages or shorter smoothing periods. We also assessed averaging methods for accuracy by individually reviewing breath-by-breath scatter plots. The 30-second block average method resulted in a lower mean peak VO2 and in an increased proportion of underestimated peak values. Using a 30-second moving average significantly increased mean peak values which increased accuracy. Similar results were found for peak RER and peak O2pulse. In conclusion, the currently recommended averaging method (30-second block average) increased the risk of misinterpretation of peak CRF values in children. Using a moving average approach decreased misinterpretation and increased accuracy.  相似文献   
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[目的/意义]采用被引次数衡量学术论文影响力存在诸多弊端。本文认为学术论文影响力包括其传播的深度、速度和广度3个方面,熵可用于衡量学术论文影响力传播的广度。[方法/过程]选择1901-2017年生物医学领域的诺贝尔奖论文作为最具影响力的论文纳入实验组,并根据1:1配对原则设立对照组,比较两组论文发表后5年内其施引文献所属学科数量、熵以及熵与被引次数的相关性。[结果/结论]实验组中65%以上的论文施引文献学科数量高于对照组;实验组熵的均值介于0.552-0.772,对照组介于0.251-0.481,有显著性差异(P<0.05);两组论文的被引次数与熵的相关性较弱,均小于0.3。结果表明:①70%以上的高影响力论文在发表早期能够影响较多的学科;②采用熵对论文影响力广度进行识别具有可行性。  相似文献   
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Purpose: There is currently no standardized testing protocol for assessing clients’ fitness/health within the Australian fitness industry. This study examined the perceptions of the feasibility of using a standardized testing protocol among Australian fitness industry professionals. Method: In 2014, 1,206 registered fitness industry professionals (aged 17–69 years) completed an online survey. Perceived feasibility for using a standardized testing protocol was assessed based on responses to 6 items. Respondents were classified as having a high level of perceived feasibility if they reported all 6 items to be “definitely feasible.” A multivariate logistic regression analysis, adjusting for demographic and fitness industry-related factors (e.g., qualification/years of experience), assessed the likelihood of having a high level of perceived feasibility. Results: Overall, 25.5% (95% CI [23.1%, 28.0%]) of the sample perceived the use of a standardized testing protocol as highly feasible. Items ranked most often as “definitely feasible” were “undertaking training to use the protocol” (55%) and “conducting follow-up testing every 6 to 12 weeks” (52%). After adjustment for the effect of confounding factors, casually employed professionals (OR = 0.63; 95% CI [0.45, 0.90]) and group instructors (OR = 0.58; 95% CI [0.41, 0.82]) were less likely to perceive standardized testing protocols as highly feasible. Conclusions: Among a large sample of Australian fitness industry professionals, slightly more than a quarter perceived using a standardized testing protocol to be highly feasible. Group instructors and casual employees perceived lower feasibility. Further research should determine the barriers to implementing a standardized testing protocol across the fitness industry.  相似文献   
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