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Purpose: In volleyball, jump execution is critical for the match outcome. Game-play-related neuromuscular impairments may manifest as decreased jump height (JH) or increased jump total duration, both of which are pivotal for performance. To investigate changes in JH and kinetics with game play, the authors conducted a prospective exploratory analysis using minimal-effect testing (MET) and equivalence testing with the 2 one-sided tests procedure, univariate, and bivariate functional principal component analysis, respectively. Methods: Twelve male varsity athletes completed 3-set matches on 2 consecutive days. Countermovement jumps were performed on a force platform immediately prematch and postmatch on days 1 and 2 and once on days 3 and 4. Results: Across sessions, JH was equivalent (P <.022, equivalence test), while total duration reported inconclusive changes (P >.227). After match 2, MET indicated that relative force at zero velocity (P =.036) decreased, while braking duration (P =.040) and time to peak force (P =.048) increased compared with baseline. With the first and second functional principal components, these alterations, together with decreased relative braking rate of force development (P =.092), were already evident after match 1. On day 4, MET indicated that relative peak force (P =.049), relative force at zero velocity (P =.023), and relative braking rate of force development (P =.021) decreased, whereas braking duration (P =.025) increased from baseline. Conclusions: Impairments in jump kinetics were evident from variables related to the countermovement-jump braking phase, while JH was equivalent. In addition to these experimental findings, the present research provides information for the choice of sample size and smallest effect size of interest when using MET and 1- and 2-dimensional analyses for countermovement-jump height and kinetics. [ABSTRACT FROM AUTHOR]

This article provides new insights into the relationship between industrialization and new forms of post-industrial development. Adopting a historical sensibility, it frames the contemporary development of the local economy of the city of Siracusa, in south-east Sicily, in an evolutionary historical perspective. The article focuses on the recent process of touristification of the city and surrounding area, analysing this process in connection with the industrialization and growth-pole strategy implemented in south-east Sicily in the post-war period. Emphasis is placed on the narratives that have been mobilized to justify different forms of development in the area, focusing in particular on the recurrent representation of the area as a periphery. Pointing out the selective use of visions of the past in post-industrial development strategies, the authors highlight how an uncomfortable industrial past has been removed from the main narratives to envision the city of Siracusa as moving towards a new phase of capitalist development. Finally, the article provides novel insights into the critical literature on tourism, showing that tourism, narrated and promoted as a sustainable and eco-compatible alternative to industrialization in Siracusa, can in fact produce highly negative impacts on the local environment and communities. [ABSTRACT FROM AUTHOR]

Introduction: With acclimatization to high altitude (HA), adaptations occur throughout the nervous system and at the level of the muscle, which may affect motor unit (MU) characteristics. However, despite the importance of MUs as the final common pathway for the control of voluntary movement, little is known about their adaptations with acclimatization. Methods: Ten lowlanders and Sherpa participated in this study 7 to 14 d after arrival at HA (5050 m), with seven lowlanders repeating the experiment at sea level (SL), 6 months after the expedition. The maximal compound muscle action potential (Mmax) was recorded from relaxed biceps brachii. During isometric elbow flexions at 10% of maximal torque, a needle electrode recorded the MU discharge rate (MUDR) and MU potential (MUP) characteristics of single biceps brachii MUs. Results: Compared with SL, acclimatized lowlanders had ~10% greater MUDR, ~11% longer MUP duration, as well as ~18% lower amplitude and ~6% greater duration of the first phase of the Mmax (all P < 0.05). No differences were noted between SL and HA for variables related to MUP shape (e.g., jitter, jiggle; P > 0.08). Apart from lower near-fiber MUP area for Sherpa than acclimatized lowlanders (P < 0.05), no Mmax or MU data were different between groups (P > 0.10). Conclusions: Like other components of the body, MUs in lowlanders adapt with acclimatization to HA. The absence of differences between acclimatized lowlanders and Sherpa suggests that evolutionary adaptations to HA are smaller for MUs than components of the cardiovascular or respiratory systems. [ABSTRACT FROM AUTHOR]