世界优秀男子400m跑运动员速度分配新特点

运用献资料法和灰色关联分析法，对世界7名优秀男子400m跑运动员的速度分配特点进行了分析。找出了影响竞赛成绩的主要因素，提出了相应的建议。     

髋部肌群对跑速的作用研究

通过对髋部肌群工作时的生理机制的研究，着重从理论与实践上阐述髋部肌群在短跑中的重要作用。提出了为了改变我国短跑水平的落后面貌，必须重视髋部肌群的力量的观点。     

Relationship between the peak time of hamstring stretch and activation during sprinting

The purpose of this study was to investigate the time series relationships between the peak musculotendon length and electromyography (EMG) activation during overground sprinting to clarify the risk of muscle strain injury incidence in each hamstring muscle. Full-body kinematics and EMG of the right biceps femoris long head (BFlh) and semitendinosus (ST) muscles were recorded in 13 male sprinters during overground sprinting at maximum effort. The hamstring musculotendon lengths during sprinting were computed using a three-dimensional musculoskeletal model. The time of the peak musculotendon length, in terms of the percentage of the running gait cycle, was measured and compared with that of the peak EMG activity. The maximum length of the hamstring muscles was noted during the late swing phase of sprinting. The peak musculotendon length was synchronous with the peak EMG activation in the BFlh muscle, while the time of peak musculotendon length in the ST muscle occurred significantly later than the peak level of EMG activation (p < 0.05). These results suggest that the BFlh muscle is exposed to an instantaneous high tensile force during the late swing phase of sprinting, indicating a higher risk for muscle strain injury.     

浅析短跑放松技术特点和训练

在短跑项目中，良好的放松技术对短跑成绩有着极其重要的影响，它能最经济、最有效地发挥运动员自身的最大潜力，取得最好的成绩。本文运用文献资料法，从生理学、心理学、训练学等角度对短跑运动员的放松技术特点及影响因素进行分析，并提出了一些有效的放松技术训练方法。     

世界优秀短跑与跨栏运动员年度及小周期训练负荷控制特征的研究

运用文献资料、特征解析和数理统计等研究方法，对短跑与跨栏运动员的年度及小周期训练负荷控制特征进行研究。结果表明：在年度不同中周期训练过程中，准备期的速度力量训练负荷量约占年度速度力量训练总负荷量的41％-42％，赛前准备期的速度力量训练负荷量约占全年速度力量训练总负荷量的43％-44％，比赛期的速度力量训练负荷量约占全年速度力量训练总负荷量的6％-7％；而小周期运动负荷的控制特征，则表现为准备期中各小周期的训练内容是以改进技术动作作为提高竞技能力的核心，并以提高最大速度和速度耐力作为身体素质训练的主要内容，但最大力量、速度力量和有氧耐力训练仍是其重要内容之一。     

短跑和中长跑运动员跳深实验中支撑时间特征的研究

目的：从运动员选材角度探讨短跑和中长跑项目运动员在跳深实验中支撑时间的特征,为支撑时间应用于田径运动员选材提供依据。方法：以上海市一、二线短跑和中长跑共84名运动员为研究对象。所有研究对象均进行身高、体重、跳深实验测试,分组研究两项目运动员支撑时间特征。结果：短跑男子优秀组最快和平均支撑时间都快于一般组（P＜0.05）,女子优秀组最快和平均支撑时间也都快于一般组（P＞0.05）,中长跑组也表现基本一致的趋势;项目之间进行比较也基本表现出一致性趋势,也就是短跑组最快和平均支撑时间基本快于相同运动等级中长跑组（P＞0.05）。结论：支撑时间在短跑和中长跑项目中具有明显的项目特征和等级特征,可以应用于短跑或中长跑项目选材。     

No effect of acute and chronic supramaximal exercise on circulating levels of the myokine SPARC

Myokines may play a role in the health benefits of regular physical activity. Secreted protein acidic rich in cysteine (SPARC) is a pleiotropic myokine that has been shown to be released into the bloodstream by skeletal muscle in response to aerobic exercise. As there is evidence suggesting that SPARC release may be linked to glycogen breakdown and activation of 5’ adenosine monophosphate-activated protein kinase, we hypothesised that brief supramaximal exercise may also be associated with increased serum SPARC levels. In the present study, 10 participants (3 women; mean?±?SD age: 21?±?3 y, body mass index (BMI): 22?±?3?kg?m^?2, and V˙O_2max: 39?±?6?mL?kg^?1?min^?1) performed an acute bout of supramaximal cycle exercise (20-s Wingate sprint against 7.5% of body mass, with a 1-min warm-up and a 3-min cool-down consisting of unloaded cycling). Serum SPARC levels were determined pre-exercise as well as 0, 15, and 60?min post-exercise and corrected for plasma volume change. To determine whether regular exercise affected the acute SPARC response, participants repeated the acute exercise protocol three times per week for four weeks, and serum SPARC response to supramaximal exercise was reassessed after this period. Acute supramaximal exercise significantly decreased plasma volume (?10%; p?<?.001), but was not associated with a significant change in serum SPARC levels at either the pre-training or post-training testing sessions. In conclusion, in contrast to aerobic exercise, a single brief supramaximal cycle sprint is not associated with an increase in serum SPARC levels, suggesting that SPARC release is not related to skeletal muscle glycogen breakdown.     

Light-load maximal lifting velocity full squat training program improves important physical and skill characteristics in futsal players

This study aimed to compare the effect of 6 weeks of resistance training or combined resistance training and change of direction exercises on physical performance and motor skills in futsal players. Thirty-four futsal players were divided into full squat group (SG, n = 12), combined full squat and change of direction exercises group (S+CDG, n = 12) and control group (CG, n = 10). The resistance training for SG consisted of full squat with low load (~45–58% 1RM) and low volume (4–6 repetitions), whereas the S+CDG performed the same resistance training program combined with loaded change of direction. Sprint time in 10 and 20 m, change of direction test, countermovement vertical jump (CMJ) height, maximal strength and force–velocity relationship in full squat exercise, kicking speed ball (BS_mean) and repeated sprint ability (RSA_mean) were selected as testing variables. Both experimental groups showed significant improvements for CMJ, BS_mean and all strength parameters. Only SG resulted in significant sprint gains, whereas S+CDG also achieved significant improvements in RSA_mean. The CG remained unchanged after training period. No significant differences were found between both experimental groups. These findings suggest that only 12 sessions of either lightweight resistance training alone, lifting the load at maximal intended velocity or combined with change of direction exercises is enough to improve several physical and skills capacities critical to futsal performance in adult players.     

Circadian rhythm effect on physical tennis performance in trained male players

To determine the effect of circadian rhythm on neuromuscular responses and kinematics related to physical tennis performance, after a standardised warm-up, 13 highly competitive male tennis players were tested twice for serve velocity/accuracy (SVA), countermovement vertical jump (CMJ), isometric handgrip strength (IS), agility T-test (AGIL) and a 10-m sprint (10-m RUN). In a randomised, counter-balance order, tennis players underwent the test battery twice, either in the morning (i.e., AM; 9:00 h) and in the afternoon (i.e., PM; 16:30 h). Paired t-tests were used to analyse differences due to time-of-day in performance variables. Comparison of morning versus afternoon testing revealed that SVA (168.5 ± 6.5 vs. 175.2 ± 6.1 km · h^?1; P = 0.003; effect size [ES] = 1.07), CMJ (32.2 ± 0.9 vs. 33.7 ± 1.1 cm; P = 0.018; ES = 1.46), AGIL (10.14 ± 0.1 vs. 9.91 ± 0.2 s; P = 0.007; ES = 1.23) and 10-m RUN time (1.74 ± 0.1 vs. 1.69 ± 0.1 s; P = 0.021; ES = 0.67) were significantly blunted during the morning testing. However, IS was not affected by time-of-day (P = 0.891). Thus, tennis performance may be reduced when competing in the morning in comparison to early evening. Therefore, coaches and tennis players should focus on schedule the SVA, power, speed and agility training sessions in the afternoon.     

江苏省女子短跑成绩实现突破的研究

对江苏省女子短跑成绩实现突破的原因进行研究。结果表明：合理的选材、科学化训练、科学的管理。决策、管理,训练三位一体的组织保障,围绕短跑项目特征及训练规律开展科学研究是提高短跑成绩的主要原因。