Publications by authors named "Leonidas Petridis"

The relationship between structural and functional of parameters of skeletal muscles in young athletes needs further observations. The analyses of their age-group differences, sexual dimorphism, asymmetry characteristics in body regions, in sports having different pattern of physical loading could serve important information in this topic. 175 elite Hungarian handball players aged between 14 and 21 years were examined in 2023.

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The relative age effects (RAEs) and biological maturation are two distinct factors that have been identified to affect talent identification and selection. Previous research has suggested that talent selection should include sport-specific technical tasks instead of body size and/or physical test measurements, assuming that the technical tasks are less influenced by variations in maturation. Our purpose was to examine the prevalence of RAEs and to assess biological maturity, body size, and body composition within a single talent selection program for female handball players.

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Background: While the acute effects of high-load resistance training on the force generating capacity of muscles have been widely examined, limited data exist on the relationship with the force-velocity profile (FV). Evidence suggests high sensitivity of the vertical FV profile to monitor changes in the muscle's mechanical properties according to the type of the exercise protocol. However, the interpretation of the findings seems not as straightforward.

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Article Synopsis
  • Variability in musculoskeletal structure, especially in the Achilles tendon moment arm and plantarflexor muscle strength, may influence hopping height, but this study found different results than expected.
  • The research tested correlations between foot and lower leg muscle structure (like muscle mass and Achilles tendon moment arm) and hopping performance, using 18 participants who performed bilateral hopping and had their lower leg structures analyzed via MRI.
  • Surprisingly, longer Achilles tendon moment arm and greater muscle force or size did not correlate with better hopping performance, suggesting that tendon mechanics and energy utilization may be more crucial than just structural factors.
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Footstrike pattern has received increased attention within the running community because there is a common belief that forefoot strike running (FFS) is more advantageous (i.e., improve performance and reduce running injuries) than rearfoot strike running (RFS) in distance running.

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The aim of the study was to develop and assess the reliability of a functional agility test containing offensive elements for water polo players. Eighteen young male (15.3 ± 0.

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Unlabelled: Talent selection is often affected by the relative age effects (RAEs), resulting in the overrepresentation of relatively older (vs. relatively younger) players among those selected. The use of sport-specific tasks is suggested to reduce RAEs during talent selection.

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Bioelectrical impedance analysis (BIA) is a common practice to assess body composition in athletes, however, when measuring athletes with specific body geometry, its accuracy may decrease. In this study we examined how length dimensions affect body composition estimation and we compared BIA and dual-energy X-ray absorptiometry (DXA) assessments in three sports. 738 male adolescent athletes (15.

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Purpose: Vertical jump is a common test to measure impulsive ability in soccer; however, limited normative data have been published on young soccer players from vertical jump measurements on a force platform. The purpose of this study was to provide normative values for three chronological age groups of male junior soccer players (U16, U17 and, U18 years).

Method: Vertical jump performance of 365 soccer players (16.

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The aim of our research was primarily to compare the conditional abilities of European countries' Fédération Internationale de Football Association (FIFA) referees with those of Hungarian national and county referees and, secondly, to investigate whether the stop tests of FIFA and the Union of European Football Associations (UEFA) provide reliable discrimination criteria between the different levels of referees. The main focuses of our research were speed and endurance, which were measured by the stop tests of FIFA and UEFA-namely, 50- and 200-m sprint runs and a 12-minute run, respectively (Cooper test). In our study, the test results of 2459 soccer referees were analyzed; they include the results of the total Hungarian population of referees and the results from 17 different European countries.

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