Learning relay start strategies in swimming: What feedback is best?

In the past, studies and book recommendations on relay starts in swimming have been predominantly focused on the change-over time (COT) as a performance criterion. Aside from the circular backswing start with parallel foot placement, few studies have analysed differences in the take-off movement including step approaches as well. Although trends could be identified, the results remained still somewhat inconclusive. In contrast, no study has examined as has examined whether a reduction of COT in between wall contact of the income swimmer and the take-off of the outgoing swimmer is an optimal relay start strategy, as advocated by various swimming experts. Therefore, the purpose of this study was to compare two different relay start strategies: offensive strategy minimizing COT and conservative strategy to maximize horizontal peak force (HPF). In this regard, a learning intervention with 24 elite-level swimmers (12 females, 12 male) was conducted to compare both strategies regarding relay start time, HPF and COT. Subjects were randomly assigned to two feedback groups: COT versus HPF at take-off. The results of this study showed a clear advantage for HPF feedback for relay start performance measured by wall contact of the incoming swimmer and head passage at 7.5?m of the outgoing swimmer. In addition, similar reductions in COTs were found in both training groups. In conclusion, swimmers should focus on force production rather than minimizing COT. For the latter, deteriorating consequences for force production must be considered.     

Analysis of anticipation by 3D motion capturing – a new method presented in karate kumite

Anticipation is an important performance factor in karate kumite. A new approach analysing anticipation in realistic combat situations by motion capturing with a high temporal resolution is presented. The advantage of this approach is that both karate athletes interacting sports specific can be recorded synchronously; thus, the presented method has the potential to analyse visual information pickup due to coordination pattern of interaction between real athletes. The aim is to demonstrate the usability of the current method for anticipation research and to investigate if the distance between two athletes and their attacking technique play a role in the reaction of the defending athlete. Furthermore, relevant cues lying within each attacking technique and little individual differences are shown. Four male karate athletes took part in this study. Logistic regression indicated that both factors (distance × attacking technique) play a significant role in reaction. However, a correlation between these factors shows that only the attacking technique is a good predictor for reaction. Results show that the attacking technique jabbing punch (jap. Kizami-Zuki) was easier to anticipate than the attacking techniques reverse punch (jap. Gyaku-Zuki) and the round kick (jap. Mawashi-Geri).     

Four weeks of high cadence training alter brain cortical activity in cyclists

ABSTRACT

Exercise at different cadences might serve as potential stimulus for functional adaptations of the brain, because cortical activation is sensitive to frequency of movement. Therefore, we investigated the effects of high (HCT) and low cadence training (LCT) on brain cortical activity during exercise as well as endurance performance.

Cyclists were randomly assigned to low and high cadence training. Over the 4-week training period, participants performed 4 h of basic endurance training as well as four additional cadence-specific exercise sessions, 60 min weekly. At baseline and after 4 weeks, participants completed an incremental exercise test with spirometry and exercise at constant load with registration of electroencephalogram (EEG).

Compared with LCT, a greater increase of frontal alpha/beta ratio was confirmed in HCT. This was based on a lower level of beta activity during exercise. Both groups showed similar improvements in maximal oxygen consumption and power at the individual anaerobic threshold.

Whereas HCT and LCT elicit similar benefits on aerobic performance, cycling at high pedalling frequencies enables participants to perform an exercise bout with less cortical activation.     

Development of raw acceleration cut-points for wrist and hip accelerometers to assess sedentary behaviour and physical activity in 5–7-year-old children

ABSTRACT

This study validated sedentary behaviour (SB), moderate-to-vigorous physical activity (MVPA) and vigorous physical activity (VPA) accelerometer cut-points in 5–7-year-old children. Participants (n = 49, 55% girls) wore an ActiGraph GT9X accelerometer, recording data at 100 Hz downloaded in 1 s epochs, on both wrists and the right hip during a standardised protocol and recess. Cut-points were generated using ROC analysis with direct observation as a criterion. Subsequently, cut-points were optimised using Confidence intervals equivalency analysis and then cross-validated in a cross-validation group. SB cut-points were 36 mg (Sensitivity (Sn) = 79.8%, Specificity (Sp) = 56.8%) for non-dominant wrist, 39 mg (Sn = 75.4%, Sp = 70.2%) for dominant wrist and 20 mg (Sn = 78%, Sp = 50.1%) for hip. MVPA cut-points were 189 mg (Sn = 82.6%, Sp = 78%) for non-dominant wrist, 181 mg (Sn = 79.1%, Sp = 76%) for dominant wrist and 95 mg (Sn = 79.3%, Sp = 75.6%) for hip. VPA cut-points were 536 mg (Sn = 75.1%, Sp = 68.7%) for non-dominant wrist, 534 mg (Sn = 67.6%, Sp = 95.6%) for dominant wrist and 325 mg (Sn = 78.2%, Sp = 96.1%) for hip. All placements demonstrated adequate levels of accuracy for SB and PA assessment.     

Differently structured advance organizers lead to different initial schemata and learning outcomes

Does the specific structure of advance organizers influence learning outcomes? In the first experiment, 48 psychology students were randomly assigned to three differently structured advance organizers: a well-structured, a well-structured and key-concept emphasizing, and a less structured advance organizer. These were followed by a sorting task, a text study phase, and a posttest. The results indicated that differently structured advance organizers lead to different proto-schemata before and different learning outcomes after the text study phase. The second experiment replicated and extended these findings with 53 mathematics students. As in experiment 1, three differently structured advance organizers were used; but to rule out alternative explanations, the sorting task between the advance organizer and the text study phase was omitted. The results showed strong beneficial effects of well-structured advance organizers on near and far transfer tasks. Taken together, both experiments support the claim that the structure of advance organizers has an effect on preliminary schemata and learning outcomes. On a general level, the results indicate that advance organizers can support the generation of proto-schemata and thus can be more than the activation of “existing” concepts in long-term memory. With regard to education, this implies that educators should not only think about whether prior domain-specific knowledge is present, but also about how to scaffold the generation of proto-schemata at the beginning of instruction.     

Gender Effects in Assessment of Economic Knowledge and Understanding: Differences Among Undergraduate Business and Economics Students in Germany,Japan, and the United States

Gender effects in large-scale assessments have become an increasingly important research area within and across countries. Yet few studies have linked differences in assessment results of male and female students in higher education to construct-relevant features of the target construct. This paper examines gender effects on students’ economic content knowledge with a focus on construct-relevant explanations. Moreover, we compare gender effects cross-nationally between Germany, Japan, and the United States. To assess economic content knowledge of higher education students, we used translated, adapted, and validated versions of the Test of Understanding in College Economics (TUCE, 4th ed.), an instrument that is commonly used internationally. We found gender effects on test scores in all three countries; effects were larger in Germany and the United States than in Japan. Gender effects were generally more pronounced on the numeracy subscale than on the literacy subscale, that is, male students had a greater edge over female students when items required calculations. In our conclusion, we discuss how numeracy and literacy items may tap different abilities.     

Children learning to read later catch up to children reading earlier

Two studies from English-speaking samples investigated the methodologically difficult question of whether the later reading achievement of children learning to read earlier or later differs. Children (n = 287) from predominantly state-funded schools were selected and they differed in whether the reading instruction age (RIA) was either five or seven years. Study 1 covered the first six years of school following three cohorts across a two-year design. Analyses accounted for receptive vocabulary, reported parental income and education, school-community affluence, classroom instruction, home literacy environment, reading self-concept, and age. The earlier RIA group had initially superior letter naming, non-word, word, and passage reading but this difference in reading skill disappeared by age 11. In Study 2, the decoding, fluency, and reading comprehension performance of 83 additional middle school-age children was compared. The two groups exhibited similar reading fluency, but the later RIA had generally greater reading comprehension. Given that the design was non-experimental, we urge further research to better understand developmental patterns and influences arising from different RIAs.     

The effect of school inspections on school improvement

This study uses a school-level longitudinal control-group design to examine how teachers and principals of inspected versus uninspected schools perceive school improvement at their schools. During the phasing in of school inspections in the states of Berlin and Brandenburg (Germany), both inspected and uninspected schools were surveyed with respect to school improvement activities over a 1-year period. The main finding is that principals’ and teachers’ perceptions of school quality were highly stable, irrespective of the introduction of school inspections. The results show school inspections had a comparatively low impact on the aspects of school quality measured here.