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Schmidt C, Perroulaz M, Perez Y, Rosset J, Wüthrich G, Malatesta D, Samozino P. A New Way to Restrict Free Leg Movement During Unilateral Vertical Jump Test. J Appl Biomech 2024; 40:21-28. [PMID: 37875253 DOI: 10.1123/jab.2022-0296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Revised: 08/22/2023] [Accepted: 08/27/2023] [Indexed: 10/26/2023]
Abstract
The purpose of this investigation was (1) to test the effect of movement restriction of the free leg during unilateral vertical jump on performance and power output comparing 2 different jump techniques: flexed (Classic technique) and straight (FC Luzern technique) free leg, and (2) to test the correlation between performance and power output obtained using these 2 techniques. Twenty elite soccer players performed squat (SJ) and countermovement (CMJ) jumps on each leg. The jump height and peak power output were compared between the 2 techniques for both legs. The jump height and peak power were significantly higher for the classic test for SJ and CMJ (P < .001) with no side effects or interactions. The angular range of motion of the free leg was higher for the Classic test than for the FC Lucerne test (P < .001), with no difference in the angular range of motion of the trunk. A moderate correlation was found between the 2 techniques on peak power (SJ: r = .626; CMJ: r = .649) and jump height (SJ: r = .742; CMJ: r = .891). Consequently, FC Lucerne technique, limiting the contribution of the free leg, is more appropriate to assess lower limb strength capacities during unilateral jump test.
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Affiliation(s)
- Christian Schmidt
- Performance Laboratory, Football Club FC Luzern, Luzern, Switzerland
| | - Mike Perroulaz
- Institute of Sport Sciences of the University of Lausanne (ISSUL), University of Lausanne, Lausanne, Switzerland
| | - Yago Perez
- Institute of Sport Sciences of the University of Lausanne (ISSUL), University of Lausanne, Lausanne, Switzerland
| | - Jérémie Rosset
- Sports and Health Center, Sports Service UNIL/EPFL, Lausanne, Switzerland
| | - Gabriel Wüthrich
- Performance Laboratory, Football Club FC Luzern, Luzern, Switzerland
| | - Davide Malatesta
- Institute of Sport Sciences of the University of Lausanne (ISSUL), University of Lausanne, Lausanne, Switzerland
| | - Pierre Samozino
- Univ Savoie Mont Blanc, Inter-university Laboratory of Motricity Biology, Chambéry, France
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2
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Kons RL, Ache-Dias J, Gheller RG, Bishop C, Detanico D. Bilateral deficit in the countermovement jump and its associations with judo-specific performance. Res Sports Med 2023; 31:638-649. [PMID: 34986710 DOI: 10.1080/15438627.2021.2024542] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Accepted: 12/26/2021] [Indexed: 10/19/2022]
Abstract
This study aimed to describe the bilateral deficit (BLD) during the countermovement jump (CMJ) in judo athletes and determine the relationship between the BLD and judo-specific performance. Fourteen male judo athletes participated. Athletes performed three specific judo tests, Maximal Sprint Speed Judo Test, Maximal Aerobic Speed Judo Test and Special Judo Fitness Test (SJFT), and double- and single-leg CMJ. The following CMJ variables were used: jump height (JH), mean (MPO) and peak (PPO) power output, peak force (PF), peak velocity (PV) and impulse (IMP). The Pearson's or Spearman's test were used (p < 0.05). The results show that the BLD is found in all CMJ parameters (20 to 31%). Negative correlations between first set of SJFTTT (total throws) and BLD in PF (r = -0.60; p= 0.022) and between the second set of SJFTTT and BLD in MPO (r= -0.74;p = 0.002), PV (r =-0.59;p = 0.025) and IMP (r =-0.55; p = 0.040) were found. Also, negative correlations between SJFTTT and the BLD in all CMJ parameters (r= -0.53 to -0.85; p < 0.05) were found. Higher values of BLD are related to poor SJFTTT performance.
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Affiliation(s)
- Rafael L Kons
- Biomechanics Laboratory, Center of Sports, Federal University of Santa Catarina, Florianópolis, Brazil
| | - Jonathan Ache-Dias
- Research Group on Technology, Sport and Rehabilitation, Catarinense Federal Institute, Araquari, Brazil
| | - Rodrigo G Gheller
- Biomechanics Laboratory, Center of Sports, Federal University of Santa Catarina, Florianópolis, Brazil
| | - Chris Bishop
- Faculty of Science and Technology, London Sport Institute, Middlesex University, London, UK
| | - Daniele Detanico
- Biomechanics Laboratory, Center of Sports, Federal University of Santa Catarina, Florianópolis, Brazil
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Tallis J, Morris RO, Duncan MJ, Eyre ELJ, Guimaraes-Ferreira L. Agreement between Force Platform and Smartphone Application-Derived Measures of Vertical Jump Height in Youth Grassroots Soccer Players. Sports (Basel) 2023; 11:117. [PMID: 37368567 DOI: 10.3390/sports11060117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2023] [Revised: 06/05/2023] [Accepted: 06/07/2023] [Indexed: 06/29/2023] Open
Abstract
Given the importance of vertical jump assessments as a performance benchmarking tool, the assessment of neuromuscular function and indicator of health status, accurate assessment is essential. This study compared countermovement jump (CMJ) height assessed using MyJump2 (JHMJ) to force-platform-derived jump height calculated from time in the air (JHTIA) and take-off velocity (JHTOV) in youth grassroots soccer players. Thirty participants (Age: 8.7 ± 0.42 yrs; 9 females) completed bilateral CMJs on force platforms whilst jump height was simultaneously evaluated using MyJump2. Intraclass correlation coefficients (ICC), Standard error of measurement (SEM), coefficient of variance (CV) and Bland-Altman analysis were used to compare performance of MyJump2 to force-platform-derived measures of CMJ height. The median jump height was 15.5 cm. Despite a high level of agreement between JHTIA and JHTOV (ICC = 0.955), CV (6.6%), mean bias (1.33 ± 1.62 cm) and 95% limits of agreement (LoA -1.85-4.51 cm) were greater than in other comparisons. JHMJ performed marginally better than JHTIA when compared to JHTOV (ICC = 0.971; 95% CI's = 0.956-0.981; SEM = 0.3 cm; CV = 5.7%; mean bias = 0.36 ± 1.61 cm; LoA = -3.52-2.80 cm). Irrespective of method, jump height did not differ between males and females (p > 0.381; r < 0.093), and the comparison between assessment tools was not affected by sex. Given low jump heights achieved in youth, JHTIA and JHMJ should be used with caution. JHTOV should be used to guarantee accuracy in the calculation of jump height.
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Affiliation(s)
- Jason Tallis
- Centre for Physical Activity, Sport and Exercise Science, Coventry University, Coventry CV1 5FB, UK
| | - Rhys O Morris
- School of Life Sciences, Coventry University, Coventry CV1 5FB, UK
| | - Michael J Duncan
- Centre for Physical Activity, Sport and Exercise Science, Coventry University, Coventry CV1 5FB, UK
| | - Emma L J Eyre
- School of Life Sciences, Coventry University, Coventry CV1 5FB, UK
| | - Lucas Guimaraes-Ferreira
- Centre for Physical Activity, Sport and Exercise Science, Coventry University, Coventry CV1 5FB, UK
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Espada MC, Jardim M, Assunção R, Estaca A, Ferreira CC, Pessôa Filho DM, Verardi CEL, Gamonales JM, Santos FJ. Lower Limb Unilateral and Bilateral Strength Asymmetry in High-Level Male Senior and Professional Football Players. Healthcare (Basel) 2023; 11:healthcare11111579. [PMID: 37297719 DOI: 10.3390/healthcare11111579] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 05/23/2023] [Accepted: 05/25/2023] [Indexed: 06/12/2023] Open
Abstract
This study sought to assess the relationship between different jumping asymmetries and associated performance variables in high-level male senior and professional football players. Nineteen football players with at least 12 years of training experience (23.2 ± 3.1 years of age; 75.2 ± 4.8 kg of body mass and 181 ± 0.06 cm of height) participated in this study performing countermovement jump (CMJ), squat jump (SJ), single-leg CMJ and drop jump (DJ), associated performance variable eccentric utilization ratio (EUR), stretch-shortening cycle (SSC), bilateral deficit (BLD), and limb symmetry index (LSI) were determined. High correlations were observed between different methodologies of jump tests and associated performance indicators (SSC, BLD, EUR), except LSI. Moreover, CMJ and SJ results were different (p < 0.05), but no differences were found between interlimb in CMJ (p = 0.19) and DJ (p = 0.14). Between the same limbs and different jumps differences were detected in CMJ and DJ (p < 0.01), and it has also been found that the laterality effect size on strength was small in CMJ (ES = 0.30) and DJ (ES = 0.35). LSI between CMJ and DJ was not different despite higher mean values in CMJ, and although mean BLD was positive (>100%), the results highlight the need for individual evaluation since eight players scored negatively. An in-depth and accurate analysis of performance in preseason screening jump tests should be considered, aiming to detect injury risk, specifically evaluating different jumping test methodologies, and determining jumping associated performance variables for each test, namely EUR, SSC, BLD, and LSI. Specific muscle-strengthening exercises could be implemented based on this study results and outcomes, aiming to reduce injury risks and lower extremity asymmetries and to enhance individual football performance in high-level male senior and professional football players. Sports institutions should pay special attention regarding potential health problems in athletes exposed to daily high training loads.
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Affiliation(s)
- Mário C Espada
- Instituto Politécnico de Setúbal, Escola Superior de Educação, 2914-504 Setúbal, Portugal
- Life Quality Research Centre, Complexo Andaluz, Avenida Dr. Mário Soares 110, 2040-413 Rio Maior, Portugal
- CIPER, Faculdade de Motricidade Humana, Universidade de Lisboa, 1499-002 Lisboa, Portugal
| | - Marco Jardim
- Instituto Politécnico de Setúbal, Escola Superior de Saúde, 2914-503 Setúbal, Portugal
| | - Rafael Assunção
- Instituto Politécnico de Setúbal, Escola Superior de Saúde, 2914-503 Setúbal, Portugal
| | - Alexandre Estaca
- Casa Pia Atlético Clube, Estádio Pina Manique, Parque de Monsanto, 1500-462 Lisboa, Portugal
| | - Cátia C Ferreira
- Instituto Politécnico de Setúbal, Escola Superior de Educação, 2914-504 Setúbal, Portugal
- Research Group in Optimization of Training and Performance Sports, Faculty of Sport Science, University of Extremadura, 10005 Cáceres, Spain
| | - Dalton M Pessôa Filho
- Department of Physical Education, São Paulo State University (UNESP), Bauru 17033-360, Brazil
- Graduate Programme in Human Development and Technology, São Paulo State University (UNESP), Rio Claro 13506-900, Brazil
| | - Carlos E L Verardi
- Department of Physical Education, São Paulo State University (UNESP), Bauru 17033-360, Brazil
- Graduate Programme in Developmental Psychology and Learning, Faculty of Science, São Paulo State University (UNESP), Bauru 17033-360, Brazil
| | - José M Gamonales
- Research Group in Optimization of Training and Performance Sports, Faculty of Sport Science, University of Extremadura, 10005 Cáceres, Spain
- Faculty of Health Sciences, University of Francisco de Vitoria, 28223 Madrid, Spain
| | - Fernando J Santos
- Instituto Politécnico de Setúbal, Escola Superior de Educação, 2914-504 Setúbal, Portugal
- Life Quality Research Centre, Complexo Andaluz, Avenida Dr. Mário Soares 110, 2040-413 Rio Maior, Portugal
- Faculdade de Motricidade Humana, Universidade de Lisboa, 1499-002 Lisboa, Portugal
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Bishop C, Abbott W, Brashill C, Loturco I, Beato M, Turner A. Seasonal Variation of Physical Performance, Bilateral Deficit, and Interlimb Asymmetry in Elite Academy Soccer Players: Which Metrics Are Sensitive to Change? J Strength Cond Res 2023; 37:358-365. [PMID: 35438675 DOI: 10.1519/jsc.0000000000004248] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
ABSTRACT Bishop, C, Abbott, W, Brashill, C, Loturco, I, Beato, M, and Turner, A. Seasonal variation of physical performance, bilateral deficit, and interlimb asymmetry in elite academy soccer players: Which metrics are sensitive to change? J Strength Cond Res 37(2): 358-365, 2023-This study aimed to report seasonal variations for (a) physical performance, (b) interlimb asymmetry, and (c) bilateral deficit (BLD) data over the course of a competitive soccer season and determine which metrics are sensitive to change. This study used a repeated-measures observational design for 19 under-20, elite, academy, soccer players (age: 17.58 ± 0.61 years; height: 1.81 ± 0.09 m; body mass: 74.36 ± 7.58 kg), who conducted bilateral and single-leg countermovement jumps (CMJ and SLCMJ), linear speed (5, 10, 20, and 30-m) and 505 change of direction (COD) speed tests, at pre, mid, and end of season time points. For jump tests, jump height, reactive strength index modified, time to takeoff, and countermovement depth metrics were monitored, with interlimb asymmetry and the BLD also calculated for each. Significant improvements ( p < 0.05) in performance were evident in all fitness tests: CMJ (effect size [ES]: 0.61 to 1.03), SLCMJ (ES: 0.60 to 2.25), linear speed (ES: -0.54 to -1.96), and COD speed (ES: -0.68 to -1.14). Significant reductions in asymmetry (ES: -0.68 to -1.07) and significant increases in the BLD (ES: 1.15 to 1.57) were also evident throughout the season. Additionally, kappa coefficients were used to determine consistency in limb dominance throughout the season, but only poor to fair levels of agreement (kappa: -0.17 to 0.37) were evident, highlighting the fluctuating nature of limb dominance throughout the season. Despite all tests exhibiting meaningful change, the SLCMJ and linear speed showed the most frequent and largest differences in performance, highlighting their usefulness in the ongoing monitoring process of physical capacities in elite male academy players across a competitive soccer season.
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Affiliation(s)
- Chris Bishop
- London Sport Institute, Faculty of Science and Technology, Middlesex University, London, United Kingdom
| | - Will Abbott
- Brighton Football Club Academy, American Express Elite Football Performance Center Brighton, United Kingdom
| | - Calum Brashill
- Brighton Football Club Academy, American Express Elite Football Performance Center Brighton, United Kingdom
| | - Irineu Loturco
- Nucleus of High Performance Sport, Sao Paulo, Brazil ; and
| | - Marco Beato
- School of Health and Sport Sciences, University of Suffolk, Ipswich, United Kingdom
| | - Anthony Turner
- London Sport Institute, Faculty of Science and Technology, Middlesex University, London, United Kingdom
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González-Ramírez A, Torres C, Magallanes C, Fábrica CG. Bilateral index, power, force, and velocity during bench press with different loads in male handball players. Front Physiol 2023; 14:1130914. [PMID: 37035666 PMCID: PMC10077126 DOI: 10.3389/fphys.2023.1130914] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Accepted: 03/09/2023] [Indexed: 04/11/2023] Open
Abstract
Bilateral index for upper limbs was determined for maximal force, speed and power in 18 male handball players. Variables were individually assessed with a functional electromechanical dynamometer during unilateral and bilateral bench press push-off for 40%, 60%, and 75% of the maximal isometric force. Limb dominance (symmetry indices) and load effects in the bilateral index were analysed. Bilateral index showed a bilateral deficit for power (range = -8.50 to -41.48) and velocity (range = -11.15 to -38.41), that increases with the load (p < 0.05). For maximum force, a bilateral facilitation (range = 2.26-5.57), which did not vary significantly as a function of load, was observed. Symmetry indices showed no association with the bilateral index (40% load: r = 0.45, 60% load: r = 0.05, 75% load: r = 0.39). These results contribute to understanding the phenomenon; however, individual-to-individual observation reflects that caution should be kept when assessing an individual athlete. In conclusion, bilateral deficit or facilitation for bench press depends on the variable considered, whereas its magnitude depends on the load. Moreover, limb dominance does not affect it. This finding must be regarded as a general trend, but a different situation may occur during the assessment of a particular athlete.
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Affiliation(s)
- Andrés González-Ramírez
- Institute of Physical Education, University of the Republic, Montevideo, Uruguay
- *Correspondence: Andrés González-Ramírez,
| | - Carol Torres
- Department of Biophysics, Faculty of Medicine, University of the Republic, Montevideo, Uruguay
| | - Carlos Magallanes
- Institute of Physical Education, University of the Republic, Montevideo, Uruguay
| | - Carlos Gabriel Fábrica
- Department of Biophysics, Faculty of Medicine, University of the Republic, Montevideo, Uruguay
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Buoite Stella A, Galimi A, Martini M, Di Lenarda L, Murena L, Deodato M. Muscle Asymmetries in the Lower Limbs of Male Soccer Players: Preliminary Findings on the Association between Countermovement Jump and Tensiomyography. Sports (Basel) 2022; 10:177. [PMID: 36422945 PMCID: PMC9694285 DOI: 10.3390/sports10110177] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Revised: 11/08/2022] [Accepted: 11/11/2022] [Indexed: 09/01/2023] Open
Abstract
Strength and power asymmetries have been observed in different sports, including soccer. Such asymmetries, as well as the bilateral deficit (BLD), can be assessed during different tasks, static or dynamic, and with different methods and devices, in order to detect the possible different aspects, as well as the association with physical performance and injuries. The aim of this study was to investigate the association between muscle asymmetries and BLD during a countermovement jump (CMJ), and tensiomyography (TMG) parameters and asymmetries, in the lower limbs of male soccer players. A total of 23 male soccer players (18 ± 4 years) were recruited. Bilateral and unilateral CMJs were performed, and peak power (W) and height (cm) were obtained. TMG was performed on different muscles of the lower limbs, and lateral and functional symmetries were obtained. Playing position and history of injuries were collected. CMJ inter-limb symmetry was found to significantly correlate with biceps femoris (r = 0.574, p = 0.004) and soleus (r = 0.437, p = 0.037) lateral symmetry. Players in central roles presented significantly worse functional symmetry scores of the knee than defense players (-17.5%, 95% CI -31.2--3.9; p = 0.10). Participants reporting a history of injury at the ankle were characterized by significantly lower functional symmetry in both the dominant (43%, 39.5-48.0 vs. 74.5%, 46.5-89.3, p = 0.019) and non-dominant (45%, 42.5-46.0 vs. 81.0%, 45.8-90.3, p = 0.024) ankle. Findings from this preliminary study suggest an association between lower-limb muscle asymmetries during a dynamic task, such as jumping, and muscle contractile properties evaluated with TMG; moreover, functional asymmetries may be present after ankle injuries. Future studies in larger samples should evaluate the presence of such asymmetries as predictors or characteristics of different muscular and joint injuries.
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Affiliation(s)
- Alex Buoite Stella
- School of Physiotherapy, Department of Medicine, Surgery and Health Sciences, University of Trieste, Via Pascoli 31, 34100 Trieste, Italy
- Clinical, Integrative and Translational Physiology, Department of Medicine, Surgery and Health Sciences, University of Trieste, Strada di Fiume 447, 34149 Trieste, Italy
| | - Annalisa Galimi
- School of Physiotherapy, Department of Medicine, Surgery and Health Sciences, University of Trieste, Via Pascoli 31, 34100 Trieste, Italy
| | - Miriam Martini
- School of Physiotherapy, Department of Medicine, Surgery and Health Sciences, University of Trieste, Via Pascoli 31, 34100 Trieste, Italy
| | - Luca Di Lenarda
- Orthopaedics and Traumatology Unit, Cattinara Hospital-ASUGI, Department of Medicine, Surgery and Health Sciences, University of Trieste, Strada di Fiume 447, 34149 Trieste, Italy
| | - Luigi Murena
- School of Physiotherapy, Department of Medicine, Surgery and Health Sciences, University of Trieste, Via Pascoli 31, 34100 Trieste, Italy
- Orthopaedics and Traumatology Unit, Cattinara Hospital-ASUGI, Department of Medicine, Surgery and Health Sciences, University of Trieste, Strada di Fiume 447, 34149 Trieste, Italy
| | - Manuela Deodato
- School of Physiotherapy, Department of Medicine, Surgery and Health Sciences, University of Trieste, Via Pascoli 31, 34100 Trieste, Italy
- Ph.D. Program in Neural and Cognitive Sciences, Department of Life Sciences, University of Trieste, Via Weiss 2, 34100 Trieste, Italy
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The Association between Bilateral Deficit and Athletic Performance: A Brief Review. Sports (Basel) 2022; 10:sports10080112. [PMID: 36006078 PMCID: PMC9413577 DOI: 10.3390/sports10080112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 07/25/2022] [Accepted: 07/25/2022] [Indexed: 12/10/2022] Open
Abstract
An abundance of information can be found in the scientific literature regarding the bilateral deficit (BLD) in different contraction types, including its possible underlying mechanisms. On the other hand, studies on the relationship between BLD and athletic performance have only begun to emerge in recent years. The purpose of this review article is to assemble and analyze the literature on the topic of the relationship between BLD and athletic performance. After a detailed review of the scientific databases, we analyzed 10 relevant scientific articles. BLD calculated from outcomes of vertical jumps was positively related to the ability to change direction quickly in volleyball, basketball, tennis and student population, but not in soccer. Sprint running performance does not seem to be associated with BLD, while one study suggested that a smaller BLD is associated with a more efficient start in a sprint. Apart from the associations with change in direction performance, there is little evidence to support the association between BLD and athletic performance; thus, further research is required in other sports, incorporating sport-specific performance outcomes and multiple tasks to calculate the BLD.
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Pleša J, Kozinc Ž, Šarabon N. Bilateral Deficit in Countermovement Jump and Its Influence on Linear Sprinting, Jumping, and Change of Direction Ability in Volleyball Players. Front Physiol 2022; 13:768906. [PMID: 35185609 PMCID: PMC8847223 DOI: 10.3389/fphys.2022.768906] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Accepted: 01/04/2022] [Indexed: 11/13/2022] Open
Abstract
We investigated the association between bilateral deficit (BLD) in the countermovement jump (CMJ) and change of direction (CoD) performance, CoD deficit, linear sprint, and approach jumping task. The participants (47 young volleyball players; age: 20.8 ± 3.8 years) performed bilateral and single-leg CMJs, modified T-test, 505 CoD test, 25-m sprints (with 5, 10, and 15 splits), and vertical approach jumps. The CoD deficit was also calculated from the 505 test and 10 m split time. BLD was calculated from CMJ jump height, peak power, and phase-specific force impulses (FIs). Several small to moderate statistically significant correlations (r = 0.42–0.49) were found between BLD and 505 times (7 correlations), sprint times (4 correlations), CoD deficit (1 correlation), and approach jump (1 correlation). T-test performance was not correlated with BLD variables (r = −0.15–0.22). The direction of the correlations indicated that the larger BLD is associated with superior performance, with the exception of 1 correlation for 505 times for the left leg and 1 for CoD deficit for the left leg. However, these two variables showed unacceptable reliability. Our results suggest that BLD could be useful in making decisions about the amount inclusion of unilateral training for volleyball players.
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Affiliation(s)
- Jernej Pleša
- Faculty of Health Sciences, University of Primorska, Izola, Slovenia
| | - Žiga Kozinc
- Faculty of Health Sciences, University of Primorska, Izola, Slovenia
- Andrej Marušič Institute, University of Primorska, Koper, Slovenia
| | - Nejc Šarabon
- Faculty of Health Sciences, University of Primorska, Izola, Slovenia
- Human Health Department, InnoRenew CoE, Izola, Slovenia
- Laboratory for Motor Control and Motor Behavior, S2P, Science to Practice, Ltd., Ljubljana, Slovenia
- *Correspondence: Nejc Šarabon,
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10
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Kozinc Ž, Šarabon N. Bilateral deficit in countermovement jump and its association with change of direction performance in basketball and tennis players. Sports Biomech 2021:1-14. [PMID: 34132633 DOI: 10.1080/14763141.2021.1942965] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2021] [Accepted: 06/09/2021] [Indexed: 10/21/2022]
Abstract
The purpose of this study was to assess the association between bilateral deficit (BLD) in countermovement jump and change of direction (CoD) performance. Therefore, 165 young basketball players (60 females) and 95 young tennis players (39 females) performed two different CoD tasks (90° and 180° turns) and bilateral and unilateral countermovement jumps. BLD was calculated based on jump height, peak power and several phase-specific force impulses (FI). For male athletes, several statistically significant small to moderate associations were found between the CoD performance and BLD (r = 0.21-0.52). While the BLD in the propulsive phase FI seems to be most consistently associated with CoD performance, all associations were weak (r = 0.21-0.28 in basketball, 0.28-0.36 in tennis). Associations between BLD in total positive (braking and propulsive phase) FI and CoD performance were moderate (r = 0.45-0.52) in male tennis players. For female athletes, the associations were even smaller and almost exclusively statistically non-significant. Although indirectly, our results imply that resistance training based on unilateral exercises could be useful to improve CoD performance. It has to be stressed that further training studies are needed to directly confirm this assumption.
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Affiliation(s)
- Žiga Kozinc
- Faculty of Health Sciences, University of Primorska, Izola, Slovenia
- Andrej Marušič Institute, University of Primorska, Koper, Slovenia
| | - Nejc Šarabon
- Faculty of Health Sciences, University of Primorska, Izola, Slovenia
- Human Health Department, InnoRenew CoE, Izola, Slovenia
- Laboratory for Motor Control and Motor Behavior, S2P, Science to Practice, Ltd., Ljubljana, Slovenia
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