网球比赛分析的几个关键点

许多运动队将全程比赛分析作为教练员的指导工具,研究己方和对方运动员的类型、战术和技术特点.网球项目中,拥有个人分析师的运动员并不多见,大部分运动员和教练员使用分析设备和程序提供的客观、可靠的反馈信息,自己进行赛前及赛后分析.很多教练员采用其他教练员的有效训练模式,因为不是所有人都有时间去分析1000h的大满贯录像来找出战术差异,但可利用他人的分析结果.赛事录像记录的客观数据提供了充足的反馈信息,教练员可根据这些反馈信息调整技战术,进行针对性的训练.     

Factors influencing the decision to administer psychoeducational tests

Ninety-nine NASP members participated in a study designed to investigate bias in the early stages of the referral process (i.e., in the decision to administer psychological tests). Each school psychologist received one of eight case studies, which described a child referred for academic learning problems. The case studies included typical referral information and varied student race (Black, White), socioeconomic status (higher, lower), and group achievement test scores (average, below average). The decision to administer individual psychoeducational tests was not influenced by the student's race or socioeconomic status. School psychologists were influenced by the group achievement test data. Students who showed lower achievement test results were more likely to be recommended for testing than were those who showed average performance levels. Thus, these school psychologists were not biased by knowledge of a child's race or socioeconomic status, but were influenced by instructionally relevant data (i.e., achievement test scores). In addition, when objective test data indicated average achievement levels, the psychologists did not generally recommend subsequent individual psychoeducational testing. The findings suggested that, under certain conditions, testing may not automatically follow receipt of a referral.     

Correlations between the stanford-binet: Fourth edition and the WISC-R with a learning disabled population

The Fourth Edition of the Stanford-Binet and the WISC-R were compared as instruments for assessing the intellectual strengths and weaknesses of students classified as learning disabled in the primary and secondary grades. Results found only a 3.28-point difference (p≥.0001) between the S-B Composite score and the WISC-R Full Scale score. Correlations between the four broad areas of the S-B and the three scales of the WISC-R ranged from .494 (S-B Abstract/Visual Reasoning with WISC-R Verbal) to .920 (S-B Composite with WISC-R Full Scale). All correlations were found to be significant. Implications of the research findings were discussed.     

Differential contribution of personality to the explanation of variance in achievement in the first language and mathematics at high school level

This study assessed the differential contribution of personality to the explanation of variance in achievement in the mother tongue and mathematics at the high school level. The results indicated that personality, as measured by the HSPQ, aided the explication of variance in achievement in the mother tongue significantly, but had little influence on mathematics. Personality contributed as much to the explanation of variance in the mother tongue as did the composite cognitive variable. The influence of personality on achievement in mathematics was shown to be negligible. Some practical implications for the teaching of the first language are drawn.     

Intrachild variabilities: Will curtailment of testing harm minority children?

Compared intrachild variability of five-year-old children (49 black, 34 white) on the Primary Mental Abilities Test when subjects reached their fifth birthday after completing at least two years of preschool enrichment. Conclusions, although qualified on the basis of limited sample size, revealed wider intrachild variability with minority children. This suggests that abandonment of testing may increase instructional problems and possibly lower the quality of instruction provided minority and poor children.     

Differences in activation patterns between eccentric and concentric quadriceps contractions.

Previous studies analysing electromyograms (EMGs) from indwelling electrodes have indicated that fast-twitch motor units are selectively recruited for low-intensity eccentric contractions. The aim of this study was to compare the frequency content of surface EMGs from quadriceps muscles during eccentric and concentric contractions at various contraction intensities. Electromyograms were recorded from the rectus femoris, vastus lateralis and vastus medialis muscles of 10 men during isokinetic (1.05 rad x s(-1)) eccentric and concentric knee extension contractions at 25%, 50%, 75% and 100% of maximal voluntary contraction (MVC) for each contraction mode. Additionally, isometric contractions (70 degrees) were performed at each intensity. The mean frequency and root mean square (RMS) of the surface EMG were computed. Mean frequency was higher for eccentric than concentric contractions at 25% (P < 0.01), 50% (P < 0.01) and 75% (P < 0.05) but not at 100% MVC. It increased with increasing contraction intensity for isometric (P < 0.001) and concentric (P < 0.01) contractions but not for eccentric contractions (P = 0.27). The EMG amplitude (RMS) increased with increasing contraction intensity similarly in each contraction mode (P < 0.0001). Higher mean frequencies for eccentric than concentric contractions at submaximal contraction intensities is consistent with more fast-twitch motor units being active during eccentric contractions.