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The people's sport? : popular sport and fans in the later years of the German Democratic Republic
(2009)
In this paper the psychometric quality of the sport-specific Volitional Components Questionnaire (VKS) is examined. After an item analysis, a factor analysis was undertaken resulted in the four factors self optimization, lack of activation, loss of focus, and self impediment. The questionnaire exhibits satisfactory internal consistency (Cronbach's alpha) and retest reliability. In line with theory (Kuhl, 2001), correlations with the general questionnaire VCQ II (Kuhl & Fuhrmann, 1998) and sport-specific action orientation as measured with the HOSP questionnaire (Beckmann, 2003) indcate construct validity. Validity can also be shown by correlations with the external criterion of expert rating by coaches. In addition, the VKS is able to differentiate between athletes who perform well and those who perforin poorly.
During experiments involving ischemic nerve block, we noticed that the short-latency response (SLR) of evoked stretches in m. soleus decreased immediately following inflation of a pneumatic cuff surrounding the lower leg. The present study aimed to investigate this short-term effect of pressure application in more detail. Fifty-eight healthy subjects were divided into seven protocols. Unilateral stretches were applied to the calf muscles to elicit a SLR, and bilateral stretches to evoke a subsequent medium-latency response (MLR). Furthermore, H-reflexes and sensory nerve action potentials (SNAPs) were recorded. Additionally, stretches were applied with different velocities and amplitudes. Finally, the SLR was investigated during hopping and in two protocols that modified the ability of the muscle-tendon complex distal to the cuff to stretch. All measurements were performed with deflated and inflated cuff. Results of the protocols were as follows: 1) inflation of the cuff reduced the SLR but not the MLR; 2) the H-reflex, the M-wave, and, 3) SNAPs of n. tibialis remained unchanged with deflated and inflated cuff; 4) the SLR was dependent on the stretch velocity with deflated and also inflated cuff; 5 and 6) the reduction of the SLR by the cuff was dependent on the elastic properties of the muscle-tendon complex distal to the cuff; and 7) the cuff reduced the SLR during hopping. The present results suggest that the cuff did not affect the reflex arc per se. It is proposed that inflation restricted stretch of the muscles underlying the cuff so that most of the length change occurred in the muscle-tendon complex distal to the cuff. As a consequence, the muscle spindles lying within the muscle may be less excited, resulting in a reduced SLR. Due to its applicability in functional tasks, the introduced method can be a useful tool to study afferent feedback in motor control.
School can be regarded as a context for a variety of leisure activities. Especially in all-day schools an increasing amount of young adolescents is spending more time in extracurricular activities. Therefore, all-day schools hold the potential to produce an "educational surplus" because it is argued that these activities contribute to the psychosocial development of adolescents. However, prior to the quest for possible developmental outcomes which could be related to extracurricular activities, another fundamental question must be responded to: Which groups of these young people do actually participate in such after-school programs? While analysing the socio-economic structure of participants for different school-organised activities, the article follows this query. For reasons of comparability, two other leisure contexts are examined: Clubs and volunteer associations as organised contexts on the one hand and a variety of informal and unstructured leisure activities on the other hand. The results reveal that extracurricular activities in schools succeed in including socially disadvantaged adolescents. The study is based on a secondary analysis of the German PISA 2000 data set.
Age-related processes in the neuromuscular and the somatosensory system are responsible for decreases in maximal and explosive force production capacity and deficits in postural control. Thus, the objectives of this study were to investigate the effects of resistance training on strength performance and on postural control in seniors. Forty healthy seniors (67 +/- 1 yrs) participated in this study. Subjects were randomly assigned to a resistance training (n = 20) and a control group (n = 20). Resistance training for the lower extremities lasted for 13 weeks at 80% of the one repetition maximum. Pre and post tests included the measurement of maximal isometric leg extension force with special emphasis on the early part of the force-time-curve and the assessment of static (functional reach test) and dynamic (tandem walk test, platform perturbation) postural control. Resistance training resulted I in an enhanced strength performance with increases I in explosive force exceeding those in maximal strength. Improved performances in the functional reach and in the tandem walk test were observed. Resistance training did not have an effect: on the compensation of platform perturbations. Increases in strength performance can primarily be explained by an improved neural drive of the agonist muscles. The inconsistent effect of resistance training on postural control may be explained by heterogeneity of testing methodology or by the incapability of isolated resisiance training to improve postural control.
Objective: Questionnaires are often applied in sports psychology to measure a person's trait or state. However, the extent to which the questionnaire captures differences because of trait or state influences is often unclear. The latent state-trait (LST) theory offers the opportunity to separate both variance sources. This separation allows estimating specific reliability coefficients. Design: The present paper gives a theoretical introduction to LST and its basic ideas. Using a real data set with N = 156 athletes we exemplify the steps necessary to derive the LST coefficients. All athletes filled out a comprehensive inventory assessing competitive anxiety on two occasions. Method: The data are analysed with structural equation models based on LST principles. Results: The results confirm the questionnaire's trait saturation. Conclusion: Finally, results are discussed in light of practical and theoretical implications.