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91.
Ying Gao Nina Nevala Neil J. Cronin Taija Finni 《European Journal of Sport Science》2016,16(6):747-754
Sit–stand workstations offer a potential strategy to reduce prolonged occupational sitting. This controlled intervention study examined the effects of an environmental intervention on occupational sedentary time, musculoskeletal comfort and work ability, and the usability of sit–stand workstations in office work via a self-reported questionnaire. The intervention group (n?=?24) used sit–stand workstations during the 6-month intervention period, and the control group (n?=?21) used traditional sitting workstations. The results showed that working at sit–stand workstations can reduce sitting time significantly compared to control workstations (?6.7% vs. 5.0%, p?=?.019), which is reallocated mostly to standing (r?=??0.719, p?.001). Sit–stand workstations improved perceived musculoskeletal comfort in the neck and shoulders (p?=?.028), as well as work ability (p?=?.022). The majority of intervention subjects rated sit–stand workstation adjustability as good (83.3%), and 75.0% were satisfied with the workstation. About 41.7% of the intervention participants, who were exclusively female, used the sit–stand function on a daily basis. While the environmental change alone was effective, it is likely that promoting the daily use of sit–stand workstations with counselling would lead to even more substantial positive effects. 相似文献
92.
Elmar Weltin Albert Gollhofer Guillaume Mornieux 《European Journal of Sport Science》2016,16(2):182-189
In lateral reactive movements, core stability may influence knee and hip joint kinematics and kinetics. Insufficient core stabilisation is discussed as a major risk factor for anterior cruciate ligament (ACL) injuries. Due to the higher probability of ACL injuries in women, this study concentrates on how gender influences trunk, pelvis and leg kinematics during lateral reactive jumps (LRJs). Perturbations were investigated in 12 men and 12 women performing LRJs under three different landing conditions: a movable landing platform was programmed to slide, resist or counteract upon landing. Potential group effects on three-dimensional trunk, pelvic, hip and knee kinematics were analysed for initial contact (IC) and the time of peak pelvic medial tilt (PPT). Regardless of landing conditions, the joint excursions in the entire lower limb joints were gender-specific. Women exhibited higher trunk left axial rotation at PPT (women: 4.0 ± 7.5°, men: ?3.1 ± 8.2°; p = 0.011) and higher hip external rotation at both IC and PPT (p < 0.01). But women demonstrated higher knee abduction compared to men. Men demonstrated more medial pelvic tilt at IC and especially PPT (men: –5.8 ± 4.9°, women: 0.3 ± 6.3°; p = 0.015). Strategies for maintaining trunk, pelvis and lower limb alignment during lateral reactive movements were gender-specific; the trunk and hip rotations displayed by the women were associated with the higher knee abduction amplitudes and therefore might reflect a movement strategy which is associated with higher injury risk. However, training interventions are needed to fully understand how gender-specific core stability strategies are related to performance and knee injury. 相似文献
93.
Martin Weiss Alexandra Newman Ceri Whitmore Stephan Weiss 《European Journal of Sport Science》2016,16(4):393-401
Sprint and distance running have experienced remarkable performance improvements over the past century. Attempts to forecast running performances share an almost similarly long history but have relied so far on relatively short data series. Here, we compile a comprehensive set of season-best performances for eight Olympically contested running events. With this data set, we conduct (1) an exponential time series analysis and (2) a power-law experience curve analysis to quantify the rate of past performance improvements and to forecast future performances until the year 2100. We find that the sprint and distance running performances of women and men improve exponentially with time and converge at yearly rates of 4% ± 3% and 2% ± 2%, respectively, towards their asymptotic limits. Running performances can also be modelled with the experience curve approach, yielding learning rates of 3% ± 1% and 6% ± 2% for the women's and men's events, respectively. Long-term trends suggest that: (1) women will continue to run 10–20% slower than men, (2) 9.50 s over 100 m dash may only be broken at the end of this century and (3) several middle- and long-distance records may be broken within the next two to three decades. The prospects of witnessing a sub-2 hour marathon before 2100 remain inconclusive. Our results should be interpreted cautiously as forecasting human behaviour is intrinsically uncertain. The future season-best sprint and distance running performances will continue to scatter around the trends identified here and may yield unexpected improvements of standing world records. 相似文献
94.
周绍平 《江苏广播电视大学学报》2005,16(6):58-60
单片机开发应用中经常用到延时控制,延时控制的基本方法有纯软件、纯硬件及软硬件结合方法,它们都有各自的特点及应用范围,以1秒延时为例给出用三种方法实现的过程,并介绍了软硬件结合延时的应用实例。 相似文献
95.
李建栋 《阜阳师范学院学报(社会科学版)》2006,(3):1-3
文章通过对《文馆词林》所存两篇残敕的文本进行分析,并将其与历史资料对照验证,得出此二敕的作者均为唐太宗,此二敕的写作时间分别为贞观二年(528)正月、三月。 相似文献
96.
易丙兰 《唐山师范学院学报》2007,29(6):77-80
华盛顿会议前后,民众通过组织国民外交团体、联合派遣国民外交代表等形式,表达自身在外交活动中的意愿和诉求,使国民外交运动在独立自主、联合发展方面有了进一步的发展。华盛顿会议后期,民众外交上的诉求未得到满足,国民外交运动由外转内,斗争目标指向北京政府。这种转变,推动了国内政局的变化,也导致了国民外交运动的分裂。 相似文献
97.
林存藩 《福建工程学院学报》2003,1(3):37-39
基于量子力学和混沌理论,补充了经典力学适用于宏观物体的数学表示式H h,并提出了经典力学第三条适用范围,即适用于不出现混沌运动的物体,其数学表示式为λ<0。 相似文献
98.
99.
李萍 《黄河科技大学学报》2003,5(2):124-126
网络时代,高校师生的学习方式和生活方式发生了深刻变化。互联网在促进教育发展和人才培养的同时,对学生的消极影响不容忽视。要多方面加强思想政治工作,如开辟网上“思想政治教育课堂”、设置“网上德育阵地”、建立信息监控等。 相似文献
100.
任彩红 《赣南师范学院学报》2004,25(1):100-104
本文主要通过对20世纪初年女子国民捐运动的考察,来探讨这一时期女子国民意识尤其是女子"义务意识"的觉醒及其发展。本文分三个部分:"女国民"意识的觉醒;女子国民捐运动的概况;女子国民捐运动的分析及其意义。 相似文献