Effects of turf and cleat footwear on plantar load distributions in adolescent American football players during resisted pushing

Metatarsal and midfoot injuries are common in American football. Footwear design may influence injury rates by altering plantar foot loading patterns in these regions. The purpose of this study was to determine the effect of cleat design on in-shoe plantar foot loading during a football-specific, resisted pushing task. Twenty competitive football players (age 14.7 ± 1.8 years, height 1.72 ± 0.10 m, and mass 71.8 ± 26.9 kg) completed three trials of pushing a weighted sled at maximal effort in a standard shoe (CLEAT) and artificial turf-specific shoe (TURF), with flexible in-shoe force measuring insoles. Repeated measures ANOVAs identified mean differences in maximum force and relative load under all regions of the foot. Results showed higher forces in the CLEAT under the medial (p < 0.001) and lateral (p = 0.004) midfoot, central (p = 0.007) and lateral (p < 0.001) forefoot, and lesser toes (p = 0.01), but lower forces in the hallux (p = 0.02) compared to the TURF shoe. Additionally, relative loading was higher in the CLEAT under the medial (p < 0.001) and lateral (p = 0.002) midfoot and lateral (p < 0.001) forefoot, but lower in the medial forefoot (p = 0.006) and hallux (p < 0.001) compared to the TURF shoe. The two shoes elicited distinct plantar loading profiles and may influence shoe selection decisions during injury prevention or rehabilitation practices.     

铅球投掷滑步技术的力学分析

铅球投掷滑步的作用不仅使铅球获得一定的预先运行速度，而且将人体处于推铅球前最良好的准备状态(精神高度集中，超越器械和拉紧有关肌群)，从而使投掷在利用滑步惯性的基础上充分发挥机体的能力对铅球进行最后的加速。     

体词性偏正组合及“的”字形式

在考查大量偏正组合的基础上,对其规律性进行描写,并试图运用音步、长度、隐形关系、配价等等从韵律、结构和语义上加以解释.指出了“的“形式的大体使用环境.此项研究无法进行穷尽式统计,对组合灵活、无特殊规律者未作介绍.     

"两步走"与"三步走"发展战略比较

实现国家现代化既是一历史课题,也是一时代性课题."两步走"与"三步走"发展战略有共同的远大的目标和阶段性发展的构想,却有着不同的探索、和解读.其间的经验和教训,对推进新时期现代化建设具有启迪和借鉴的作用.     

篮球裁判员处理带球走时应注意的几个问题

持球队员是否带球走的依据是中枢脚在持球时是否有移动，因此确定队员的中枢脚是判断持球队员是否有带球走的关越．一脚抬起的一刹那，另一脚就变成中枢脚．明确球、手、脚之间的关系，队员只有球在手上，才有可能发生带球走违例．     

中国服装品牌命名现象分析

品牌命名不仅是营销中的一个重要环节，同时也是语言文字应用的一个重要领域。这里选取服装作为研究对象，对其品牌命名现象作详细的分析，并从各个角度全面把握其特点，在此基础上总结归纳命名原则。     

Initiating running barefoot: Effects on muscle activation and impact accelerations in habitually rearfoot shod runners

Runners tend to shift from a rearfoot to a forefoot strike pattern when running barefoot. However, it is unclear how the first attempts at running barefoot affect habitually rearfoot shod runners. Due to the inconsistency of their recently adopted barefoot technique, a number of new barefoot-related running injuries are emerging among novice barefoot runners. The aim of this study was therefore to analyse the influence of three running conditions (natural barefoot [BF], barefoot with a forced rearfoot strike [BRS], and shod [SH]) on muscle activity and impact accelerations in habitually rearfoot shod runners. Twenty-two participants ran at 60% of their maximal aerobic speed while foot strike, tibial and head impact accelerations, and tibialis anterior (TA), peroneus longus (PL), gastrocnemius medialis (GM) and gastrocnemius lateralis (GL) muscle activity were registered. Only 68% of the runners adopted a non-rearfoot strike pattern during BF. Running BF led to a reduction of TA activity as well as to an increase of GL and GM activity compared to BRS and SH. Furthermore, BRS increased tibial peak acceleration, tibial magnitude and tibial acceleration rate compared to SH and BF. In conclusion, 32% of our runners showed a rearfoot strike pattern at the first attempts at running barefoot, which corresponds to a running style (BRS) that led to increased muscle activation and impact accelerations and thereby to a potentially higher risk of injury compared to running shod.     

以旧创新--论弗罗斯特诗中的"带意义的语调"

弗罗斯特在华兹华斯诗歌语言传统的基础上创造性地提出了“带意义的语调”的概念，形成自己独特的作诗法，文章对他的“带意义的语调”进行了深入分析，运用详实的例子说明了它在表情达意方面不可忽视的作用。     

足部按摩与运动员疲劳恢复

借助中医理论、循环理论和运动生理学理论,探讨了足部按摩的特殊功效,结合运动训练和体育竞赛过程中运动员产生疲劳的机理,阐明了利用足部按摩手段促进运动员疲劳恢复的方法,进而为丰富运动员疲劳恢复方法,提高运动员的训练和比赛适应能力,创造更有益的成绩做有益的探索。     

跑步中足底各区域温度状态变化初步研究

运动时,人体足部鞋腔内的环境主要包括温度与湿度两个重要方面。然而,目前对鞋内温湿度的研究相对比较少,研究方法主要为足部散热模型建立与实验验证相结合,模型主要考虑不同足部组织的热传导系数、动静脉血液热传递、汗液挥发等因素,通过与足部接触的温湿度传感器或红外摄像仪进行温度数据采集。