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This study examined the alterations induced by a simulated tennis competition on maximal isometric voluntary contraction (MVC), peak rate of force development (PRFD) and rate of force development (RFD) at different stages of contraction. Twenty junior tennis players performed an 80-minute simulated tennis match and two (pre and post) muscular performance tests. Variables tested included MVC, PRFD and RFD at 50, 100, 150 and 200 ms while performing a 90º shoulder internal rotation (IR90), 90º shoulder external rotation (ER90), shoulder horizontal adduction (ADD), shoulder horizontal abduction (ABD) and isometric mid-thigh pull (IMTP). Serve velocity (SV) was also registered. No significant changes were found regarding MVC, PRFD or SV. Non-significant moderate effect size (ES) towards a decrease in the IR90 RFD at 50 ms could be observed (16%; ES = 0.5) alongside an increase in the ADD and IMTP RFD at 150 ms (-15.8%, -8.2%; ES = -0.53, -0.54) and IMTP RFD at 200 ms (-13%; ES = -0.54). Results indicate that MVC, PRFD, RFD at different time intervals and SV are unaltered following an 80-minute simulated match, possibly due to insufficient alterations triggered on key factors affecting the tested variables.
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http://dx.doi.org/10.52082/jssm.2022.245 | DOI Listing |
bioRxiv
July 2025
Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, UK.
Protein phosphatase 2A (PP2A), an important therapeutic target, comprises a scaffold subunit PR65 composed of 15 HEAT (Huntingtin/elongation/A-subunit/TOR1) repeats, a catalytic subunit, and one of many different regulatory subunits that enable binding to specific substrates. Recently, small molecule activators of PP2A (SMAPs) were identified, although their mechanisms of action have not been fully defined. Here we explore the interaction of PR65 with two SMAPs, ATUX-8385 and the non-functional DBK-776, using single-molecule optical tweezers, ensemble methods, and computational analysis.
View Article and Find Full Text PDFDisabil Rehabil Assist Technol
August 2025
Centre d'Etudes et de Recherche sur l'Appareillage des Handicapés (CERAH), Institution Nationale des Invalides, Paris, France.
: Rolling resistance (RR) significantly impacts the energy efficiency of manual wheelchair propulsion, influencing both daily mobility and sports performance. RR increases when weight shifts forward, making casters a critical contributor. This study aimed to isolate and evaluate the effects of caster diameter, hardness, cross-section, and caster type on RR across diverse surfaces, including sports and everyday environments.
View Article and Find Full Text PDFGerontology
July 2025
Sports, Exercise and Brain Sciences Laboratory, Sports Coaching College, Beijing Sport University, Beijing, China.
Introduction: Decline in balance is a major risk factor for falls among older adults. Virtual reality (VR)-based training can enhance neural activation and sensorimotor integration, offering a promising approach for improving balance in older adults. However, the effects of immersive VR-based tennis training on balance in older adults remain unclear.
View Article and Find Full Text PDFJ Sports Sci
July 2025
College of Physical Education, Shaanxi Normal University, Xi 'an, China.
Recent studies have shown that AO+MI (Action Observation and Motor Imagery) based on visual-guided demonstration models effectively enhances the learning of complex motor skills. However, the role of essential information in these demonstration models has not been fully explored. Given the importance of visual guidance in AO+MI, we hypothesize that muscle activation color visual guidance can further improve learning efficiency.
View Article and Find Full Text PDFFront Sports Act Living
July 2025
Department of Sport Games, Hungarian University of Sports Science, Budapest, Hungary.
Introduction: This study aims to compare different playing styles on external training load and rating of perceived exertion (RPE) in elite Hungarian junior tennis players during the off-season in winning vs. losing matches.
Methods: Sixteen elite male junior tennis players from the same club participated in this study (aggressive baseliner: = 9; counterpuncher: = 7), and each player was required to play three simulated matches.