The effects of static stretching on speed and agility: One or multiple repetition protocols?     

Alexandra Avloniti  Ioannis G. Fatouros  Maria Protopapa  Ioannis Athanailidis  Christina Avloniti 《European Journal of Sport Science》2016,16(4):402-408

Although static stretching (SS) is utilized during warm-up before training and competition, the results about its effects on performance remain controversial. We examined whether performing a stretch of short-to-moderate duration (<60 sec) in a single repetition produces a similar or different effect on speed and agility performance from the effect which is produced while performing the same stretch in multiple repetitions of the same total duration. According to a repeated measurement design, 40 trained males were randomly assigned to either (1) a single repetition group or (2) a multiple repetition group. The participants in each group performed five trials: a control trial (no stretches were performed) and four experimental trials of SS protocols consisting of five exercises performed at either 20 sec (2 × 10 in the second group), 30 sec (3 × 10 in the second group), 40 sec (4 × 10 in the second group) or 60 sec (6 × 10 in the second group) of total duration. A two-way repeated measures analysis of variance showed that the participants in both group improved their speed performance in response to the 20-sec trial, whereas agility remained unaffected. Data analysis also revealed that the repetition number did not affect speed and agility performance. These data suggest that SS of short duration (<30 sec) may actually improve acute speed performance, whereas SS of moderate duration may not hamper speed and agility performance. Moreover, the effects of SS protocols are related to the total duration of each exercise and not to the number of repetitions in which each exercise is performed.  相似文献   

A study of the Greek school teachers' moral judgment structures     

Miltiadis Proios  Joannis Athanailidis  Vasiliki Arvanitidou 《Teachers and Teaching》2013,19(2):187-200

The purpose of the present paper is to examine the teachers' cognitive structures through moral judgment schemas, as well as whether the above‐mentioned structures diversify among teachers, depending on education level, specialty, age, teaching experience, and gender. Moreover, another aim is to examine whether these cognitive structures can predict students' behaviors. Two hundred and fifty eight in‐service teachers (men, n = 83; women, n = 175; M _age = 41.24, SD = 8.06; M _experiences = 14.91, SD = 9.46), in elementary (n = 96), and intermediate education level (n = 158), participated in the study. The results revealed that the primary education teachers' moral judgment is based on the moral concepts of the maintaining norms schema, while the one of those of secondary education is rather based on the postconventional schema. Furthermore, the results of the present study revealed that age, experience, and gender do not constitute causes of diversification of moral concepts and that the personal interest schema can forecast any irresponsible behaviors on the part of the students.  相似文献