The cumulative and residual fatigue response associated with soccer-specific activity performed on different playing surfaces

ABSTRACT

This study aimed to assess the effect of playing surface (Natural [NT] and Artificial [AT] Turf) on the fatigue response to a soccer-specific exercise protocol (SSEP). Eighteen male soccer players completed the SSEP on NT and AT with pre-, post-, and 48 h post-assessments of eccentric knee flexor (eccKF) and concentric knee extensor peak torque (PT), peak countermovement (CMJ) and squat jump (SJ) height, and Nordic hamstring break angle. No significant main effects for surface or any surface and time interactions were observed for any of the outcome measures, except for eccKF PT recorded at 3.14 rad·s^-1, which was significantly lower 48 h post-trial in the AT condition (AT = 146.3 ± 20.4 Nm; NT = 158.8 ± 24.7 Nm). Main effects for time were observed between pre- and post-trial measures for eccKF PT at all angular velocities, Nordic break angle, CMJ and SJ height. Nordic break angle, and both CMJ and SJ height were significantly impaired 48 h post-trial when compared to pre-trial. The findings of the current study suggest surface dependent changes in eccKF PT which may have implications for recovery and subsequent performance after competition on AT.     

Explorations in promoting conceptual change in electrical concepts via ontological category shift

Chi (1992, 1993) Chi et al. (1994) suggests that many of the difficulties encountered by students in learning Physics concepts arise because they attribute the ontology of material substances to these concepts. These concepts are actually a special type of process - 'Constraint-Based Interactions' (CBI). Slotta and Chi (1996) reported on a study where a group of students explicitly trained in the CBI ontology showed significant gains over a control group in problem solving performance in eight simple electric circuit problems. This paper reports on a series of four studies which explore the usefulness of the ontological categorization framework in investigating students' alternative conceptions of electric circuits and in developing a teaching strategy for promoting conceptual change in the learning of basic electric circuitry concepts.     

Television: The performance of nonresident students in the “economics U$A” telecourse

Abstract

Correspondence study represents the first and most persistent distance education format in American universities. Later called independent study, it enabled universities to disseminate instruction far beyond their campuses. Yet, national‐level leadership provided by the National University Continuing Education Association (NUEA) and its divisions has been relatively restrained. In contrast, leadership in the private correspondence school sector has been assertive, and sometimes even aggressive. The NUEA and its members shunned this approach, choosing instead to lead by persuasion and example. The NUEA developed standards of practice concerned primarily with replicating on‐campus teaching styles and values, rather than the promotion of distance education. With the abolition of its division structure, the NUEA's successor, the University Continuing Education Association (UCEA), has opted out of a leadership role in independent study. This paper concludes that the NUEA's initial attempt at leadership in distance education— while reasoned and principled—contained flaws that made failure inevitable.