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891.
The aim of this cohort study is to analyse the effect of three types of treatment: (i) exercise training with multicomponent exercise (E); (ii) pharmacologic treatment with oral hypoglycaemic drug – metformin (M); and (iii) a combined therapy – exercise and metformin (E?+?M) on health-related quality of life (HRQoL) and mood states in older adults with type 2 diabetes (T2D) with comorbidity in an early stage of the disease. Participants (n?=?284) underwent 1 of the following 3 conditions: (i) E (n?=?59) trained three times/week; (ii) M (n?=?30) used 850?mg of metformin twice daily; and (iii) E?+?M (n?=?195) combined exercise and metformin. Furthermore, participants completed baseline and 2-year follow-up evaluations including a Shortform Health Survey 36, Profile of Mood States – Short-form, the health history questionnaires, anthropometric, and blood biochemistry. E and E?+?M revealed improved mood states, with large effect size on the vigour domain, and moderate effect size in the anger and total mood disturbance (TMD) domains (P?<?0.05), in comparison with the M group. After 24 months’ intervention, the E and E?+?M groups perceived better physical and mental HRQoL than the M group. The M group unchanged HRQoL domains (P?>?0.05). Metformin had no significant effect on the self-referred HRQoL in T2D participants aged above 60 years, in an early stage of the disease. The E and E?+?M were the most effective long-term therapies to improve mood states and HRQoL in older adults with T2D.  相似文献   
892.
The aim of this article was to understand how active power is used in squat and countermovement jumps. A simple empirical model comprising a mass, a spring, an active element and a damper, together with an optimisation principle, was used to identify the mechanical factors that maximise performance of jumps without countermovement (squat jumps, SJ) and with countermovement (CMJ). Twelve amateur volleyball players performed SJ from two initial positions and CMJ with two degrees of counterbalancing, while kinematic data were collected (jump height, push-off duration and position of the centre of mass). The model adjusted well to real data of SJ through all the impulse phase, and slightly less adequately at the end of this phase for CMJ. Nevertheless, it provides a satisfactory explanation for the generation and utilisation of active power for both type of jumps. On average, the estimated power of the active elements, the spring, and the damper were greater in the SJ. Based upon the result obtained with this model, we suggest that active power is best evaluated with SJ. The reason for this is that, during this kind of jump, the elements associated with the damper consume much of the energy produced by the active elements. The participation of the elements that consume the energy generated by the active elements is less in CMJ than in SJ, allowing for a better utilisation of this energy. In this way it is possible to achieve a better performance in CMJ with less active power.  相似文献   
893.
Purpose: There is a paucity of research investigating the expression of mitogen-activated protein kinases (MAPK) in chronically trained (CT) athletes. Thus, it is unclear how MAPK may contribute to performance and muscle adaptation in CT subjects. The purpose of this study was to determine MAPK total protein, and phosphorylated expression of extracellular signal-regulated kinases 1 and 2 (ERK1/2), c-Jun N-terminal kinase (JNK), and p38-MAPK (p38) between untrained, and chronically trained runners. Methods: Tissue samples were analysed from sedentary (SED; n?=?5) controls and chronically trained runners (CT; n?=?5). Resting muscle biopsy samples were analysed for total-MAPK – and ratio of phosphorylated/total (p-MAPK) – ERK1/2, JNK, and p38-MAPK via western blotting. Mann–Whitney U tests and effect sizes were utilized to determine differences in total MAPK protein content and phosphorylation status between SED and CT subjects. Results: There was no difference in total-MAPK expression between SED and CT (p?>?.05). p-p38-MAPK tended to be greater for CT compared to SED (p?=?.07). There were moderate effect sizes of decreased pERK/total-ERK (d?=??0.69) and increased pJNK/total-JNK (d?=?0.54) in CT compared to SED. There was a positive correlation between p-p38-MAPK/total-MAPK and the percentage of type I fibres (r?=?0.73, p?=?.016). Conclusion: Contrary to previous studies, chronic endurance training does not greatly influence total MAPK protein expression in chronically trained runners. However, resting phosphorylation of p38-MAPK may contribute to enhanced oxidative metabolism at chronically trained levels. These alterations are likely involved in the different physiological adaptations that occur following long-term training or at highly competitive levels.  相似文献   
894.
Abstract

Quiet eye training (QET) may be a more effective method for teaching children to catch than traditional training (TT) methods, but it is unclear if the benefits accrued persist in the long term. Thirty children were randomly allocated into a QET or TT group and, while wearing a mobile eye tracker, underwent baseline testing, training and two retention tests over a period of eight weeks, using a validated throw and catch task. During training, movement-related information was provided to both groups, while the QET group received additional instruction to increase the duration of their targeting fixation (QE1) on the wall prior to the throw, and pursuit tracking (QE2) period on the ball prior to catching. In both immediate (R1) and delayed (R2, six weeks later) retention tests, the QET group had a significantly longer QE1 duration and an earlier and longer QE2 duration, compared to the TT group, who revealed no improvements. A performance advantage was also found for the QET compared to the TT group at both R1 and R2, revealing the relatively robust nature of the visuomotor alterations. Regression analyses suggested that only the duration of QE1 predicted variance in catch success post-training, pointing to the importance of a pre-programming visuomotor strategy for successful throw and catch performance.  相似文献   
895.
This article examines the frontier between the Seljuk Sultanate of Rūm and its Byzantine neighbours in the thirteenth century, concentrating on the place of these frontier districts within the Seljuk state. Scholarship on the frontier, influenced by the ideas of Paul Wittek, has seen it as something of a “no man's land”, politically, economically, culturally and religiously distinct from the urban heartland of the Seljuk sultanate in central Anatolia, dominated by the nomadic Turks, the Turkmen, who operated largely beyond sultanic control. It is often thought that the Seljuk and Greek sides of the border shared more in common with each other than they did with the states of which they formed a part. In contrast, this article argues that in fact the western frontier regions were closely integrated into the Seljuk sultanate. Furthermore, with the Mongol domination of the Seljuk sultanate in the second half of the thirteenth century, the Seljuk and Mongol elites became increasingly involved in this frontier region, where some of the leading figures of the sultanate had estates and endowments.  相似文献   
896.
This study examines the linguistic and cultural intersections of recently arrived Somali Bantu refugee students in South Texas through the lens of border theory. The use of Spanish in the homes of refugee families is explored in addition to ways in which an educator used testimonios to honor students’ migration experiences. Findings show how specific approaches used in schools that affirm both the receiving communities’ and the new arrivals' local knowledge can have a lasting impact on literacy acquisition and resettlement experiences. Findings from this study also illuminate the potential impact of educators who develop a critical, inquiry stance by embedding multiple entry points for students to cross social, cultural, linguistic, and curricular borders in school.  相似文献   
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900.
In a “post-NCLB era,” the schooling experiences of mostly low-income students of color continue to be consumed by a test-prep pedagogy—narrowed curriculum, low expectations, and ignored relationships. In this article the author describes a pedagogical approach using educational dialogues to engage preservice teachers to critically define a quality education.  相似文献   
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