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Soler A, Agulló F, Hernández-Davó J, Raya-González J, Del Coso J, González-Ródenas J, Moreno-Pérez V. Influence of the External Workload on Calf Muscle Strain Injuries in Professional Football Players: A Pilot Study. Sports Health 2024:19417381241247754. [PMID: 38708680 DOI: 10.1177/19417381241247754] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/07/2024] Open
Abstract
BACKGROUND The influence of external workload variables on the development of calf muscle strainsin football players has not been previously explored. HYPOTHESIS Overloaded players would have an increased risk of calf muscle strain injury. STUDY DESIGN Prospective observational study. LEVEL OF EVIDENCE Level 4. METHODS A total of 41 professional football players from 1 team were monitored for 2 consecutive seasons. Total distance covered (TD), and distances covered at high-intensity running, high sprint running, low (LACC) and high (HACC) acceleration, low (LDEC) and high (HDEC) deceleration, and at high metabolic load distance (HMLD) were monitored with GPS units. Accumulated players' external workload in the week before injury was compared with the weekly mean value of the 6 weeks before injury occurred for each player. RESULTS Ten players (24.3%) suffered 16 calf muscle strain injuries (3.1 injuries per 1000 hours of match play; 0.5 injuries per 1000 hours of training exposure). Players with a calf muscle injury were older (p = 0.03), with higher body weight (p = 0.01) and height (p = 0.03). Injured players displayed substantially higher total training volume (p < 0.01), TD (p < 0.01), LACC (p < 0.01), LDEC (p < 0.01), HACC (p < 0.01), HDEC (p < 0.01), and HMLD (p = 0.03) in the week before injury, in comparison with the mean values of these variables in the 6 weeks before injury. CONCLUSION A week with a higher-than-habitual external workload might increase the risk of calf muscle strain injury in professional football players. Calf muscle injuries were preceded by a week with unusually high workloads associated with accelerating and decelerating distances and higher training volumes. CLINICAL RELEVANCE Monitoring external workload indicators may be helpful in determine players with a higher risk of calf muscle strain injury due to excessive workload during training/competition.
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Affiliation(s)
| | | | | | | | - Juan Del Coso
- Sport Sciences Research Centre, Rey Juan Carlos University, Spain
| | | | - Víctor Moreno-Pérez
- Sports Research Center, Miguel Hernandez University of Elche, Alicante, Spain
- Center for Translational Research in Physiotherapy, Department of Pathology and Surgery, Miguel Hernandez University of Elche, San Joan, Spain
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Aoki A, Tamura T, Hoshi K, Gamada K. Effect of unpredictable timing on the hip, knee, and ankle kinematics and center of mass during deceleration tasks. J Sports Med Phys Fitness 2024; 64:425-431. [PMID: 38445844 DOI: 10.23736/s0022-4707.23.15344-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2024]
Abstract
BACKGROUND Unpredictable stopping or deceleration tasks are crucial to prevent ACL injury. The purpose of this study was to reveal differences and relationships in kinematics during different deceleration tasks with and without anticipation. METHODS Twenty-four collegiate athletes were recruited. Three commercial video cameras were used to capture frontal and sagittal lower-extremity kinematics. Participants were instructed to perform three deceleration tasks: 1) anticipated stopping and running backward at a point indicated previously (SRB-P); 2) anticipated stopping and running backward in front of a badminton net (SRB-N); and 3) unanticipated stopping and running backward upon random flashing of a light (SRB-U). Differences and relationships between hip, knee, and ankle kinematics at stopping (SS) and deceleration steps (DS) and the height of the great trochanter (HGT) at SS were analyzed. RESULTS For all tasks, the knee flexion angle was less than 25° at SS. There were no significant differences in hip, knee, and ankle kinematics between tasks. HGT during SRB-U was higher than that in the other tasks at DS. Hip flexion angle at SS and DS was significantly correlated with HGT at SS. During SRB_P and SRB_N, only knee flexion angle at DS was significantly correlated with HGT at SS. CONCLUSIONS The deceleration task in this study, SRB, causes a low knee-flexion angle at SS. The COM remained higher during unanticipated stopping, which is related only to hip flexion angle during the task. Knee flexion movement does not contribute to lowering COM during an unpredictable deceleration task.
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Affiliation(s)
- Akino Aoki
- Department of Physical Therapy, International University of Health and Welfare, Narita, Japan -
| | - Tomoyo Tamura
- Graduate School of Medical Technology and Health Welfare Science, Hiroshima International University, Higashihiroshima, Japan
| | - Kenji Hoshi
- Department of Rehabilitation, Kato Orthopedic Sports Clinic, Hiroshima, Japan
| | - Kazuyoshi Gamada
- Faculty of Rehabilitation, Hiroshima International University, Higashihiroshima, Japan
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Swinton PA, Schoenfeld BJ, Murphy A. Dose-Response Modelling of Resistance Exercise Across Outcome Domains in Strength and Conditioning: A Meta-analysis. Sports Med 2024:10.1007/s40279-024-02006-3. [PMID: 38652410 DOI: 10.1007/s40279-024-02006-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/14/2024] [Indexed: 04/25/2024]
Abstract
BACKGROUND Resistance exercise is the most common training modality included within strength and conditioning (S&C) practice. Understanding dose-response relationships between resistance training and a range of outcomes relevant to physical and sporting performance is of primary importance for quality S&C prescription. OBJECTIVES The aim of this meta-analysis was to use contemporary modelling techniques to investigate resistance-only and resistance-dominant training interventions, and explore relationships between training variables (frequency, volume, intensity), participant characteristics (training status, sex), and improvements across a range of outcome domains including maximum strength, power, vertical jump, change of direction, and sprinting performance. METHODS Data were obtained from a database of training studies conducted between 1962 and 2018, which comprised healthy trained or untrained adults engaged in resistance-only or resistance-dominant interventions. Studies were not required to include a control group. Standardized mean difference effect sizes were calculated and interventions categorized according to a range of training variables describing frequency (number of sessions per week), volume (number of sets and repetitions performed), overall intensity (intensity of effort and load, categorised as low, medium or high), and intensity of load (represented as % of one-repetition maximum [1RM] prescribed). Contemporary modelling techniques including Bayesian mixed-effects meta-analytic models were fitted to investigate linear and non-linear dose-responses with models compared based on predictive accuracy. RESULTS Data from a total of 295 studies comprising 535 groups and 6,710 participants were included with analyses conducted on time points ≤ 26 weeks. The best performing model included: duration from baseline, average number of sets, and the main and interaction effects between outcome domain and intensity of load (% 1RM) expressed non-linearly. Model performance was not improved by the inclusion of participant training status or sex. CONCLUSIONS The current meta-analysis represents the most comprehensive investigation of dose-response relationships across a range of outcome domains commonly targeted within strength and conditioning to date. Results demonstrate the magnitude of improvements is predominantly influenced by training intensity of load and the outcome measured. When considering the effects of intensity as a % 1RM, profiles differ across outcome domains with maximum strength likely to be maximised with the heaviest loads, vertical jump performance likely to be maximised with relatively light loads (~ 30% 1RM), and power likely to be maximised with low to moderate loads (40-70% 1RM).
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Affiliation(s)
- Paul Alan Swinton
- School of Health Sciences, Robert Gordon University, Garthdee Road, Aberdeen, AB10 7QG, UK.
| | - Brad J Schoenfeld
- Department of Exercise Science and Recreation, CUNY Lehman College, Bronx, NY, USA
| | - Andrew Murphy
- School of Health Sciences, Robert Gordon University, Garthdee Road, Aberdeen, AB10 7QG, UK
- Greater Western Sydney Giants, Sydney, NSW, Australia
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Barrera-Domínguez FJ, Jones PA, Almagro BJ, Molina-López J. Determination of change of direction deficit thresholds across a spectrum of angles in basketball players. J Sports Sci 2024; 42:621-628. [PMID: 38739494 DOI: 10.1080/02640414.2024.2354624] [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: 10/27/2023] [Accepted: 05/05/2024] [Indexed: 05/16/2024]
Abstract
Change of direction deficit (CODD) offers valuable insights into a player's balance between linear and multidirectional speed. However, there are still no established reference values for CODD. The objectives of this study were to determine CODD thresholds for various change of direction angles in basketball players according to gender and analyse the relationships between CODD and execution time in speed tests. One hundred and thirty basketball players (46% female; age: 23.7 ± 5.29 years; height: 189.1 ± 11.1 cm; body mass: 84.3 ± 15.7 kg) undertook 10-m linear and change of direction speed test at 45º, 90º and 180º. A k-means cluster analysis was conducted to standardise CODD thresholds and a one-way analysis of variance to identify the differences between clusters. The results revealed angulation-specific CODD thresholds, ranging from 3% to 8%, 17% to 25% and 43% to 51% for 45º, 90º and 180º cutting angles, respectively for the pooled sample. Furthermore, differences inter-clusters (p < 0.05) were observed for execution time at all cutting angles for both genders. Therefore, strength and conditioning coaches are encouraged to assess CODD as a highly valid variable for evaluating change of direction performance and to use current CODD thresholds to tailor training programmes according to each athlete's needs.
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Affiliation(s)
| | - Paul A Jones
- Sport, Exercise and Physiotherapy, University of Salford, Greater Manchester, UK
| | - Bartolomé J Almagro
- Faculty of Education, Psychology and Sport Sciences, COIDESO, University of Huelva, Huelva, Spain
| | - Jorge Molina-López
- Faculty of Education, Psychology and Sport Sciences, COIDESO, University of Huelva, Huelva, Spain
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Baena-Raya A, Díez-Fernández DM, Martínez-Rubio C, Conceição F, López-Sagarra A. Kinetic and Kinematic Characteristics Underpinning Change of Direction Performance in Basketball: A Comparative Study Between Sexes and Tests. J Strength Cond Res 2024; 38:e182-e188. [PMID: 38300789 DOI: 10.1519/jsc.0000000000004693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2024]
Abstract
ABSTRACT Baena-Raya, A, Díez-Fernández, DM, Martínez-Rubio, C, Conceição, F, and López-Sagarra, A. Kinetic and kinematic characteristics underpinning change of direction performance in basketball: A comparative study between sexes and tests. J Strength Cond Res 38(4): e182-e188, 2024-This study (a) evaluated the sex-specific kinetic and kinematic outcomes underpinning change of direction (COD) performance, (b) compared these outcomes across 3 different COD tests, and (c) examined the sex-specific and test-specific outcome most strongly related to COD performance in basketball players. Thirty young basketball players (17 males and 13 females) competing at the national level were assessed for the modified 505 test, modified T test, and V-cut test. The Local Positioning System technology (WIMU PRO, Realtrack Systems S.L., Almería, Spain) was used to measure the maximum values of acceleration (ACC max ), deceleration (DEC max ), velocity (VEL max ), and centripetal force (CentF max ) in each COD test. Male players displayed greater ACC max , VEL max , DEC max , and CentF max outputs for each section of the 505 test, T test, and V-cut test (all p < 0.05), resulting in a faster COD performance than females across tests (all ES > -1.42; 95% CI = -3.45 to -0.57). The 505 test demanded significantly greater kinematic outputs than T test and V-cut test for both sexes ( p < 0.01). The ACC max explained ∼26-58% of the variability in COD time for males across tests ( p < 0.05) and 40% in females' modified 505-test time ( p < 0.05). Likewise, in females, DEC max explained 38% of the modified T -test time variability, whereas VEL max explained 53% in the V-cut test time (both p < 0.05). These findings suggest that (a) COD data should not be used interchangeably across sexes, (b) test specificities should be considered for designing COD training, and (c) the kinematic outcomes explaining COD performance might vary across sexes.
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Affiliation(s)
- Andrés Baena-Raya
- Department of Education, Faculty of Education Sciences, University of Almería, Almería, Spain
- SPORT Research Group (CTS-1024), CERNEP Research Center, University of Almería, Almería, Spain
| | - David M Díez-Fernández
- Department of Education, Faculty of Education Sciences, University of Almería, Almería, Spain
- SPORT Research Group (CTS-1024), CERNEP Research Center, University of Almería, Almería, Spain
| | - Carlos Martínez-Rubio
- SPORT Research Group (CTS-1024), CERNEP Research Center, University of Almería, Almería, Spain
| | - Filipe Conceição
- Center of Research, Education, Innovation and Intervention in Sport, Faculty of Sports, University of Porto, Porto, Portugal; and
- LABIOMEP-Porto Biomechanics Laboratory, University of Porto, Porto, Portugal
| | - Andrés López-Sagarra
- SPORT Research Group (CTS-1024), CERNEP Research Center, University of Almería, Almería, Spain
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Negra Y, Sammoud S, Bouguezzi R, Moran J, Chaabene H. Effects of a horizontal speed deceleration training programme on measures of physical fitness in youth male handball players. J Sports Sci 2024; 42:638-645. [PMID: 38762890 DOI: 10.1080/02640414.2024.2356440] [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: 07/04/2023] [Accepted: 05/09/2024] [Indexed: 05/21/2024]
Abstract
This study examined the effects of an 8-week horizontal speed deceleration training (HSDT) programme in combination with regular handball-specific training as compared with handball-specific training only in measures of physical fitness in male youth handball players. Thirty-nine players were randomly assigned to either an HSDT group (n = 18; 15.55 ± 0.24 years) or an active-control group (CG; n = 21; 14.59 ± 0.23 years). The results showed significant and large between-group differences at post-test in countermovement jump, change-of-direction speed, and repeated sprint ability (RSA) (all p < 0.01; d = 2.04 and 1.37, 1.39, 1.53, and 1.53 for the CMJ, 505 CoD, RSAbest, RSAaverage, and RSAtotal performances, respectively). The post-hoc-analysis demonstrated significant and large improvements in all measures of physical fitness in the HSDT group (∆2.49% to 16,25%; d = 1.01 to 1,70; all p < 0,01). The CG, however, failed to reach any significant difference in all measures of physical fitness ((∆0.31% to 1.98%; d = 0.15 to 0.22; p = 0.379; p > 0.05). To summarise, an 8-week in-season HSDT programme alongside regular handball-specific training yielded positive effects on various performance measures including jumping ability, CoD speed, and RSA, when compared to handball-specific training alone. These results highlight the potential benefits of integrating HSDT into the training regimen of youth handball athletes during the competitive season.
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Affiliation(s)
- Yassine Negra
- Research Laboratory (LR23JS01), Sport Performance, Health & Society, La Manouba, Tunisia
- Higher Institute of Sport and Physical Education of Ksar Saïd, University of "La Manouba", Tunisia
| | - Senda Sammoud
- Research Laboratory (LR23JS01), Sport Performance, Health & Society, La Manouba, Tunisia
| | - Raja Bouguezzi
- Research Laboratory (LR23JS01), Sport Performance, Health & Society, La Manouba, Tunisia
| | - Jason Moran
- School of Sport, Rehabilitation, and Exercise Sciences, University of Essex, Colchester, UK
| | - Helmi Chaabene
- Department of Sport Science, Chair for Health and Physical Activity/Otto-von-Guericke University Magdeburg, Magdeburg, Germany
- High Institute of Sports and Physical Education, Kef, University of Jendouba, Jendouba, Tunisia
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Dugdale JH, Myers T, Sanders D, Andrew M, Clarke R, Hunter AM. Evaluation of multi-directional speed qualities throughout adolescence in youth soccer: The non-linear nature of transfer. J Sports Sci 2024; 42:301-312. [PMID: 38484363 DOI: 10.1080/02640414.2024.2329846] [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: 03/01/2023] [Accepted: 03/04/2024] [Indexed: 04/23/2024]
Abstract
Training and assessment of agility is often prioritised by soccer coaches and practitioners aiming to develop multi-directional speed. Although the importance of agility is advocated throughout childhood and adolescence, limited data evidence agility performance at different stages of adolescence. The purpose of this study was to examine differences in multi-directional speed performance in youth soccer players spanning an entire soccer academy. A total of 86 male junior-elite soccer players volunteered to participate. Anthropometric data were collected, alongside performance data from a battery of physical tests including sprinting, jumping, change of direction, reaction time, and agility. Bayesian models using log-likelihoods from posterior simulations of parameter values displayed linear or curvilinear relationships between both chronological and biological age and performance in all tests other than agility and reaction time. For agility and reaction time tests, performance improved until ~14 years of age or the estimated age of peak height velocity whereby arrested development in performance was observed. Our results demonstrate that while most performance skills improve as chronological or biological age increases, measures of agility and reaction time may not. These findings support the notion that agility performance is complex and multifaceted, eliciting unique, challenging physical demands and non-linear development.
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Affiliation(s)
- James H Dugdale
- School of Applied Sciences, Edinburgh Napier University, Edinburgh, UK
| | - Tony Myers
- Sport, Physical Activity and Health Research Centre, Newman University, Birmingham, UK
| | - Dajo Sanders
- Department of Human Movement Science, Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, Netherlands
| | - Matthew Andrew
- Department for Sport and Exercise Sciences, Institute of Sport, Manchester Metropolitan University, Manchester, UK
| | - Richard Clarke
- Faculty of Life Sciences and Education, University of South Wales, Wales, UK
| | - Angus M Hunter
- Department of Sport Science, Nottingham Trent University, Nottingham, UK
- Faculty of Health Sciences and Sport, University of Stirling, Stirling, UK
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Cross J, Kung SM, Welch N. Assessing the reliability of biomechanical variables during a horizontal deceleration task in healthy adults. J Sports Sci 2024; 42:263-269. [PMID: 38484285 DOI: 10.1080/02640414.2024.2327874] [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: 09/04/2023] [Accepted: 03/01/2024] [Indexed: 04/23/2024]
Abstract
Horizontal deceleration technique is an underpinning factor to musculoskeletal injury risk and performance in multidirectional sport. This study primarily assessed within- and between-session reliability of biomechanical and performance-based aspects of a horizontal deceleration technique and secondarily investigated the effects of limb dominance on reliability. Fifteen participants completed four horizontal decelerations on each leg during test and retest sessions. A three-dimensional motion analysis system was used to collect kinetic and kinematic data. Completion time, ground contact time, rate of horizontal deceleration, minimum centre of mass height, peak eccentric force, impulse ratio, touchdown distance, sagittal plane foot and knee angles at initial contact, maximum sagittal plane thorax angle, and maximum knee flexion moment were assessed. Coefficients of variation (COV) and intraclass correlation coefficients (ICC) were used to assess within- and between-session reliability, respectively. Seven variables showed "great" within-session reliability bilaterally (COV ≤9.13%). ICC scores were 'excellent' (≥0.91; n = 4), or 'good' (0.76-0.89; n = 7), bilaterally. Limb dominance affected five variables; three were more reliable for the dominant leg. This horizontal deceleration task was reliable for most variables, with little effect of limb dominance on reliability. This deceleration task may be reliably used to assess and track changes in deceleration technique in healthy adults.
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Affiliation(s)
- Joshua Cross
- Sports Medicine Department, UPMC Sports Surgery Clinic, Dublin, Ireland
| | - Stacey M Kung
- Sports Medicine Department, UPMC Sports Surgery Clinic, Dublin, Ireland
| | - Neil Welch
- Sports Medicine Department, UPMC Sports Surgery Clinic, Dublin, Ireland
- School of Health and Human Performance, Dublin City University, Dublin, Ireland
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Daly LS, Catháin CÓ, Kelly DT. Do players with superior physiological attributes outwork their less-conditioned counterparts? A study in Gaelic football. Biol Sport 2024; 41:163-174. [PMID: 38188097 PMCID: PMC10765432 DOI: 10.5114/biolsport.2024.129479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 03/30/2023] [Accepted: 06/09/2023] [Indexed: 01/09/2024] Open
Abstract
This study investigated the association of physiological attributes with in-game workload measures during competitive Gaelic football match-play. Fifty-two male developmental level Gaelic football players (mean ± SD; age: 22.9 ± 3.8 years) underwent measurements of anthropometric characteristics, running speed, muscular strength and power, blood lactate (BLa), running economy and aerobic capacity during two separate testing visits. Global Positioning System units (18-Hz) were used to record players in-game workloads during a competitive match 1-week following the baseline physiological assessments. Results indicated that players body fat percentage, drop jump height (DJ) and running velocity at 4 mmol · L-1 BLa were significantly associated with the number of high-speed runs completed (Adjusted R2 26.8% to 39.5%; p < 0.05) while 20 m running speed, running velocity at 2 mmol · L-1 BLa and DJ were significantly associated with the number of accelerations completed (Adjusted R2 17.2% to 22.0%; p < 0.05) during match-play. Additionally, aerobic capacity and body fat percentage were significantly associated with total distance (Adjusted R2 14.4% to 22.4%; p < 0.05) while body fat percentage, DJ and 20 m running speed were significantly associated with high-speed distance (Adjusted R2 17.8% to 22.0%; p < 0.05). Players were also divided into higher-standard and lower-standard groups using a median split of these physiological attributes. Players in the higher-standard groups completed significantly more high-speed runs and accelerations and covered significantly larger total and high-speed distances (+10.4% to +36.8%; ES = 0.67 to 0.88; p < 0.05) when compared to the lower-standard groups. This study demonstrates that superior levels of physical conditioning are associated with larger in-game workloads during Gaelic football match-play.
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Affiliation(s)
- Lorcan S. Daly
- Department of Sport and Health Sciences, Technological University of the Shannon, Ireland
- SHE Research group, Technological University of the Shannon, Ireland
- Department of Physical Education and Sport Sciences, University of Limerick, Ireland
- Sport and Human Research Centre, University of Limerick, Ireland
| | - Ciarán Ó. Catháin
- Department of Sport and Health Sciences, Technological University of the Shannon, Ireland
- SHE Research group, Technological University of the Shannon, Ireland
| | - David T. Kelly
- Department of Sport and Health Sciences, Technological University of the Shannon, Ireland
- SHE Research group, Technological University of the Shannon, Ireland
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Westheim F, Gløersen Ø, Harper D, Laugsand H, Eriksrud O. Reliability of phase-specific outcome measurements in change-of-direction tests using a motorized resistance device. Front Sports Act Living 2023; 5:1212414. [PMID: 37936876 PMCID: PMC10626501 DOI: 10.3389/fspor.2023.1212414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Accepted: 08/30/2023] [Indexed: 11/09/2023] Open
Abstract
This study aims to determine test-retest reliability of phase-specific information during initial acceleration, deceleration, and re-acceleration phases of different change-of-direction (CoD) tests using a motorized resistance device (MRD). A total of 21 participants (16 males and five females, with mean age of 22.3 ± 3.9 years, body mass of 75.2 ± 6.9 kg, height of 177.9 ± 6.8 cm) completed the modified 505 (m505), 10-0-5, and 15-0-5 CoD tests on four different test sessions while exposed to an external load (3 kg) provided by the MRD. Outcome variables included overall and phase-specific kinetic (force, power, and impulse) and kinematic (time, distance, velocity, and acceleration/deceleration) data during the initial acceleration, deceleration, and re-acceleration phases. The deceleration and re-acceleration phases were further divided into two subphases, namely, early and late subphases, using 50% of maximum velocity. Reliability was assessed using an intraclass correlation coefficient (ICC), coefficient of variation (CV), typical error (TE), and minimal detectable change (MDC). Good to excellent ICC values (>0.75) and acceptable (<10%) to good (<5%) CV values were observed for most outcome measurements. Specifically, 80.1% (822 out of 1,026) of all variables showed good or better relative reliability (i.e., ICC ≥ 0.75), while 97.0% (995 out of 1,026) of all variables showed acceptable or better absolute reliability (i.e., CV < 10%). In conclusion, the present study demonstrates that the MRD can obtain reliable phase-specific outcome measurements across different CoD tests, providing coaches and researchers with new opportunities to advance our understanding of CoD ability and inform more advanced CoD training prescriptions.
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Affiliation(s)
- Frederic Westheim
- Biomechanics Laboratory, Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway
| | - Øyvind Gløersen
- Biomechanics Laboratory, Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway
| | - Damian Harper
- School of Sport and Health Sciences, Institute of Coaching and Performance, University of Central Lancashire, Preston, United Kingdom
| | - Håkon Laugsand
- Biomechanics Laboratory, Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway
| | - Ola Eriksrud
- Biomechanics Laboratory, Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway
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Thieschäfer L, Klütz J, Weig J, Dos’Santos T, Büsch D. Development of a Cutting Technique Modification Training Program and Evaluation of its Effects on Movement Quality and Cutting Performance in Male Adolescent American Football Players. Sports (Basel) 2023; 11:184. [PMID: 37755861 PMCID: PMC10534889 DOI: 10.3390/sports11090184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Revised: 09/11/2023] [Accepted: 09/13/2023] [Indexed: 09/28/2023] Open
Abstract
This study developed a cutting technique modification training program and investigated its effects on cutting performance and movement quality in adolescent American football players. For six weeks, an intervention group (IG) of 11 players participated in 25 min cutting technique modification training sessions integrated into team training twice a week, while a control group (CG) of 11 players continued their usual team training. Movement quality was assessed by evaluating 2D high-speed videos, obtained during preplanned 45° and 90° cutting tests, using the Cutting Movement Assessment Score (CMAS) qualitative screening tool. Cutting performance was assessed based on change of direction deficit (CODD). Significant interaction effects of time × group were found for CMAS in 45° and 90° cuttings (p < 0.001, ηp2 = 0.76, p < 0.001, ηp2 = 0.64, respectively), with large improvements in the IG (p < 0.001, g = -2.16, p < 0.001, g = -1.78, respectively) and deteriorations in the CG for 45° cuttings (p = 0.002, g = 1.15). However, no statistically significant differences in CODD were observed pre-to-post intervention. The cutting technique modification training was effective at improving movement quality without impairing cutting performance, and it can be used by practitioners working with adolescent athletes.
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Affiliation(s)
- Lutz Thieschäfer
- Institute of Sport Science, Carl von Ossietzky University Oldenburg, 26129 Oldenburg, Germany (D.B.)
| | - Julius Klütz
- Institute of Sport Science, Carl von Ossietzky University Oldenburg, 26129 Oldenburg, Germany (D.B.)
| | - Julian Weig
- Institute of Sport Science, Carl von Ossietzky University Oldenburg, 26129 Oldenburg, Germany (D.B.)
| | - Thomas Dos’Santos
- Department of Sport and Exercise Sciences, Musculoskeletal Science and Sports Medicine Research Centre, Manchester Metropolitan University, Manchester M1 7EL, UK;
- Manchester Institute of Sport, Manchester Metropolitan University, Manchester M1 7EL, UK
| | - Dirk Büsch
- Institute of Sport Science, Carl von Ossietzky University Oldenburg, 26129 Oldenburg, Germany (D.B.)
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Bustamante-Garrido A, Izquierdo M, Miarka B, Cuartero-Navarrete A, Pérez-Contreras J, Aedo-Muñoz E, Cerda-Kohler H. Mechanical Determinants of Sprinting and Change of Direction in Elite Female Field Hockey Players. SENSORS (BASEL, SWITZERLAND) 2023; 23:7663. [PMID: 37765720 PMCID: PMC10537788 DOI: 10.3390/s23187663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2023] [Revised: 08/29/2023] [Accepted: 08/31/2023] [Indexed: 09/29/2023]
Abstract
Profile determination in field hockey is critical to determining athletes' physical strengths and weaknesses, and is key in planning, programming, and monitoring training. This study pursued two primary objectives: (i) to provide descriptive data on sprinting, deceleration, and change of direction (COD) abilities and (ii) to elucidate the mechanical variables that influence sprint and COD performance in elite female field hockey players. Using radar and time-gate technology, we assessed performance and mechanical data from 30 m sprinting, deceleration, and COD tests for 26 elite female hockey players. A machine learning approach identified mechanical variables related to sprint and COD performance. Our findings offer a framework for athlete categorization and the design of performance-enhancing training strategies at the international level. Two pivotal mechanical variables-relative maximum horizontal force (F0) and maximum velocity (Vmax)-predominantly influence the times across all tested distances. However, the force-velocity profile (FVP) and horizontal deceleration do not influence the variance in the COD test outcomes. These insights can guide the design, adjustment, and monitoring of training programs, assisting coaches in decision making to optimize performance and mitigate injury risks for female hockey players.
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Affiliation(s)
- Alejandro Bustamante-Garrido
- Escuela de Ciencias del Deporte y la Actividad Física, Facultad de Salud, Universidad Santo Tomás, Santiago 8370003, Chile; (A.B.-G.); (J.P.-C.)
- Navarrabiomed, Hospitalario Universitario de Navarra (HUN), Universidad Pública de Navarra (UPNA), IdiSNA, 31008 Pamplona, Spain;
- Departamento de Educación Física, Deportes y Recreación, Facultad de Artes y Educación Física, Universidad Metropolitana de Ciencias de la Educación, Santiago 7760197, Chile
- Laboratorio de Biomecánica Deportiva, Unidad de Ciencias Aplicadas al Deporte, Instituto Nacional de Deportes, Ministerio del Deporte de Chile, Santiago 7750000, Chile
| | - Mikel Izquierdo
- Navarrabiomed, Hospitalario Universitario de Navarra (HUN), Universidad Pública de Navarra (UPNA), IdiSNA, 31008 Pamplona, Spain;
| | - Bianca Miarka
- Laboratory of Psychophysiology and Performance in Sports and Combats, Postgraduate Program in Physical Education, School of Physical Education and Sport, Federal University of Rio de Janeiro, Rio de Janeiro 21941-599, Brazil;
| | | | - Jorge Pérez-Contreras
- Escuela de Ciencias del Deporte y la Actividad Física, Facultad de Salud, Universidad Santo Tomás, Santiago 8370003, Chile; (A.B.-G.); (J.P.-C.)
- Departamento de Educación Física, Deportes y Recreación, Facultad de Artes y Educación Física, Universidad Metropolitana de Ciencias de la Educación, Santiago 7760197, Chile
- Escuela de Doctorado, Universidad de las Palmas de Gran Canaria (EDULPGC), 35001 Las Palmas, Spain
| | - Esteban Aedo-Muñoz
- Departamento de Educación Física, Deportes y Recreación, Facultad de Artes y Educación Física, Universidad Metropolitana de Ciencias de la Educación, Santiago 7760197, Chile
- Laboratorio de Biomecánica Deportiva, Unidad de Ciencias Aplicadas al Deporte, Instituto Nacional de Deportes, Ministerio del Deporte de Chile, Santiago 7750000, Chile
- Laboratory of Psychophysiology and Performance in Sports and Combats, Postgraduate Program in Physical Education, School of Physical Education and Sport, Federal University of Rio de Janeiro, Rio de Janeiro 21941-599, Brazil;
- Escuela de Ciencias de la Actividad Física, el Deporte y la Salud, Facultad de Ciencias Médicas, Universidad de Santiago de Chile, Santiago 9170022, Chile
| | - Hugo Cerda-Kohler
- Departamento de Educación Física, Deportes y Recreación, Facultad de Artes y Educación Física, Universidad Metropolitana de Ciencias de la Educación, Santiago 7760197, Chile
- Laboratory of Psychophysiology and Performance in Sports and Combats, Postgraduate Program in Physical Education, School of Physical Education and Sport, Federal University of Rio de Janeiro, Rio de Janeiro 21941-599, Brazil;
- Unidad de Fisiología del Ejercicio, Centro de Innovación, Clínica MEDS, Santiago 7691236, Chile
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Freitas TT, Pereira LA, Zabaloy S, Alcaraz PE, Arruda AFS, Mercer VP, Bishop C, Loturco I. Change-of-Direction and Deceleration Deficits in National-Team Female Rugby Sevens Players: Interrelationships and Associations With Speed-Related Performance. Int J Sports Physiol Perform 2023; 18:1079-1084. [PMID: 37567578 DOI: 10.1123/ijspp.2023-0150] [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: 04/16/2023] [Revised: 07/06/2023] [Accepted: 07/24/2023] [Indexed: 08/13/2023]
Abstract
PURPOSE To investigate the relationships between a series of direct and indirect measures of linear and multidirectional speed performance in elite female rugby sevens players. METHODS Nineteen players from the Brazilian national team performed 40-m linear sprint and 505 change-of-direction (COD) tests on the same day. Based on the linear sprint and COD test performances, the COD deficit (CODD) and deceleration deficit (DD) were also obtained. A Pearson product-moment correlation analysis was used to determine the relationships between linear sprint and COD-derived variables. RESULTS Linear sprint and 505 COD velocities were not significantly associated (P > .05). Large to very large significant associations (r values ranging from .54 to .78; P < .05) were detected between linear sprint velocity for the different distances tested (10, 15, 30, and 40 m) and CODD. The COD velocity presented a very large inverse significant correlation with CODD and DD (r = -.77 and -.79 respectively; P < .05). A large and significant correlation was identified between CODD and DD (r = .79; P < .05). CONCLUSIONS Significant associations were observed between linear sprint and CODD, suggesting that faster players are less efficient at changing direction. No relationship was found between sprint velocity and DD, highlighting the independent nature of linear sprints and deceleration capabilities. A comprehensive and detailed analysis of multidirectional speed performance should consider not only linear sprint and COD performances but also complementary COD-derived variables such as the CODD and DD.
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Affiliation(s)
- Tomás T Freitas
- UCAM Research Center for High Performance Sport, UCAM Universidad Católica de Murcia, Murcia,Spain
- Facultad de Deporte, UCAM Universidad Católica de Murcia, Murcia,Spain
- NAR-Nucleus of High Performance in Sport, São Paulo,Brazil
- Department of Human Movement Sciences, Federal University of São Paulo, São Paulo,Brazil
| | - Lucas A Pereira
- NAR-Nucleus of High Performance in Sport, São Paulo,Brazil
- Department of Human Movement Sciences, Federal University of São Paulo, São Paulo,Brazil
| | - Santiago Zabaloy
- Carnegie School of Sport, Leeds Rhinos, Leeds,United Kingdom
- Leeds Beckett University, Leeds,United Kingdom
| | - Pedro E Alcaraz
- UCAM Research Center for High Performance Sport, UCAM Universidad Católica de Murcia, Murcia,Spain
| | | | - Valter P Mercer
- NAR-Nucleus of High Performance in Sport, São Paulo,Brazil
- Department of Human Movement Sciences, Federal University of São Paulo, São Paulo,Brazil
| | - Chris Bishop
- Faculty of Science and Technology, London Sports Institute, Middlesex University, London,United Kingdom
| | - Irineu Loturco
- NAR-Nucleus of High Performance in Sport, São Paulo,Brazil
- Department of Human Movement Sciences, Federal University of São Paulo, São Paulo,Brazil
- University of South Wales, Wales,United Kingdom
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Wolfe C, Page P, Voight M, Norman C, Draovitch P. The Deceleration Index - Is it the Missing Link in Rehabilitation? Int J Sports Phys Ther 2023; 18:73799. [PMID: 37020440 PMCID: PMC10069389 DOI: 10.26603/001c.73799] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2023] Open
Abstract
The ability to decelerate is a key component of any successful rehabilitation program, yet it is often overlooked in favor of more traditional forms of rehabilitation and training. Deceleration, which is defined as the ability to reduce speed or momentum and stop or change direction, can be a key component of successful rehabilitation. The deceleration index is a new metric being used by some physical therapists and rehabilitation specialists to improve patient outcomes. The index is based on the principle that deceleration forces should match those created with acceleration. When patients can quickly and efficiently decelerate during physical activity, they are less likely to experience pain or injury. While the deceleration index is still in its early stages of development, there is promising evidence that it could be the missing link in effective rehabilitation. In this editorial commentary, we'll explore what the deceleration index is and why it is important to the rehabilitation process.
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Affiliation(s)
- Chris Wolfe
- Doctor of Physical Therapy Program Belmont University
| | - Phil Page
- Doctor of Physical Therapy Program Franciscan University
| | | | - Connor Norman
- Director of Sports Medicine-Football University of Georgia
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García-Sánchez C, Navarro RM, Karcher C, de la Rubia A. Physical Demands during Official Competitions in Elite Handball: A Systematic Review. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:3353. [PMID: 36834047 PMCID: PMC9965087 DOI: 10.3390/ijerph20043353] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 02/08/2023] [Accepted: 02/10/2023] [Indexed: 06/10/2023]
Abstract
An understanding of physical demands during official competitions is essential to achieving the highest performance in handball. The aim of this systematic review was to summarise the available scientific evidence associated with physical demands during official competitions in elite handball according to playing positions, competition level and gender. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, 17 studies were selected after a systematic search and selection process of three digital databases: PubMed, Web of Science and Sport Discus. The quality of the selected studies was evaluated using the Strengthening the Reporting of Observational Studies in Epidemiology checklist; the average score was 18.47 points. The sample consisted of 1175 handball players, of whom 1042 were men (88.68%) and 133 were women (11.32%). The results show that an elite handball player covered on average 3664.4 ± 1121.6 m during a match. The average running pace was 84.8 ± 17.2 m∙min-1. The total distance covered was largely greater in national competitions (4506.7 ± 647.9 m) compared with international competitions (2190.3 ± 1950.5 m) (effect size (ES) = 1.2); however, the running pace did not present any significant difference between the international or national level (ES = 0.06). In regard to gender, the total distance covered was moderately greater in female competitions (4549.1 ± 758.6 m) compared with male competitions (3332.6 ± 1257.7 m) (ES = 0.9), and the running pace was largely greater in female competitions (110.5 ± 7.2 m∙min-1) compared with male competitions (78.4 ± 19.7 m∙min-1) (ES = 1.6). In relation to playing position, backs and wings covered a moderately greater total distance (ES = 0.7 and 0.6) and slightly more meters per minute (ES = 0.4 and 0.2) than pivots. Moreover, the technical activity profile differed between playing positions. Backs performed moderately more throws than pivots and wings (ES = 1.2 and 0.9), pivots exhibited largely more body contact than backs and wings, and wings performed moderately more fast breaks (6.7 ± 3.0) than backs (2.2 ± 2.3) (ES = 1.8). Therefore, this research study provides practical applications for handball coaches and strength and conditioning professionals with respect to designing and implementing more individualised training programmes to maximise performance and reduce injury risk.
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Affiliation(s)
- Carlos García-Sánchez
- Deporte y Entrenamiento Research Group, Departamento de Deportes, Facultad de Ciencias de la Actividad Física y del Deporte (INEF), Universidad Politécnica de Madrid, C/Martín Fierro 7, 28040 Madrid, Spain
| | - Rafael Manuel Navarro
- Department of Sports Sciences, European University of Madrid, 28670 Villaviciosa de Odón, Spain
| | - Claude Karcher
- Oxidative Stress and Muscular Protection Laboratory (EA 3072), Faculty of Medicine, Mitochondria, University of Strasbourg, 67081 Strasbourg, France
- European Centre for Education, Research and Innovation in Exercise Physiology (CEERIPE), Faculty of Sport Sciences, University of Strasbourg, 67000 Strasbourg, France
- Centre de Ressources, d’Expertises et de Performances Sportives, CREPS de Strasbourg, 67200 Strasbourg, France
| | - Alfonso de la Rubia
- Deporte y Entrenamiento Research Group, Departamento de Deportes, Facultad de Ciencias de la Actividad Física y del Deporte (INEF), Universidad Politécnica de Madrid, C/Martín Fierro 7, 28040 Madrid, Spain
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McPherson AL, Schilaty ND, Anderson S, Nagai T, Bates NA. Arthrogenic muscle inhibition after anterior cruciate ligament injury: Injured and uninjured limb recovery over time. Front Sports Act Living 2023; 5:1143376. [PMID: 37025459 PMCID: PMC10072230 DOI: 10.3389/fspor.2023.1143376] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 02/15/2023] [Indexed: 04/08/2023] Open
Abstract
Introduction It is well documented that marked weakness of the quadriceps is present after knee joint injury. This joint trauma induces a presynaptic reflex inhibition of musculature surrounding the joint, termed arthrogenic muscle inhibition (AMI). The extent to which anterior cruciate ligament (ACL) injury affects thigh musculature motor unit activity, which may affect restoration of thigh muscle strength after injury, is undetermined. Methods A randomized protocol of knee flexion and extension isometric contractions (10%-50% maximal voluntary isometric contraction) were performed for each leg on 54 subjects with electromyography array electrodes placed on the vastus medialis, vastus lateralis, semitendinosus, and biceps femoris. Longitudinal assessments for motor unit recruitment and average firing rate were acquired at 6-month intervals for 1 year post ACL injury. Results The ACL-injured population demonstrated smaller quadriceps and hamstrings motor unit size (assessed via motor unit action potential peak-to-peak amplitude) and altered firing rate activity in both injured and uninjured limbs compared to healthy controls. Motor unit activity remained altered compared to healthy controls at 12 months post ACL reconstruction (ACLR). Discussion Motor unit activity was altered after ACLR up to 12 months post-surgery. Further research is warranted to optimize rehabilitation interventions that adequately address altered motor unit activity and improve safety and success with return to sport after ACLR. In the interim, evidence based clinical reasoning with a focus on development of muscular strength and power capacity should be the impetus behind rehabilitation programming to address motor control deficits.
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Affiliation(s)
- April L. McPherson
- Emory Sport Performance and Research Center, Emory University, Flowery Branch, GA, United States
- Department of Orthopaedics, The Ohio State University, Columbus, OH, United States
- Department of Physiology & Biomedical Engineering, Mayo Clinic, Rochester, MN, United States
- Correspondence: April L. McPherson
| | - Nathan D. Schilaty
- Department of Physiology & Biomedical Engineering, Mayo Clinic, Rochester, MN, United States
- Department of Physical Medicine & Rehabilitation, Rochester, MN, United States
- Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN, United States
- Sports Medicine Center, Mayo Clinic, Rochester, MN, United States
- Department of Neurosurgery & Brain Repair, University of South Florida, Tampa, FL, United States
- Department of Medical Engineering, University of South Florida, Tampa, FL, United States
| | - Sarah Anderson
- Department of Physical Medicine & Rehabilitation, Rochester, MN, United States
- Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN, United States
- Sports Medicine Center, Mayo Clinic, Rochester, MN, United States
| | - Takashi Nagai
- Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN, United States
- Sports Medicine Center, Mayo Clinic, Rochester, MN, United States
- United States Army Research Institute of Environmental Medicine, Natick, MA, United States
| | - Nathaniel A. Bates
- Department of Orthopaedics, The Ohio State University, Columbus, OH, United States
- Department of Physiology & Biomedical Engineering, Mayo Clinic, Rochester, MN, United States
- Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN, United States
- Sports Medicine Center, Mayo Clinic, Rochester, MN, United States
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Volk NR, Vuong JL, Ferrauti A. Relevance of force-velocity and change of direction assessments for the ranking position in elite junior tennis players. Front Sports Act Living 2023; 5:1140320. [PMID: 36923295 PMCID: PMC10009273 DOI: 10.3389/fspor.2023.1140320] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2023] [Accepted: 02/06/2023] [Indexed: 03/03/2023] Open
Abstract
Purpose This study aimed to correlate sprint mechanical parameters (SMP) of a linear sprint (LS) and a tennis specific modified 505 (Tm505) change of direction (CoD) test obtained with a motorized resistance device (MRD) to the current tennis ranking position (RP). Methods 107 male and 86 female elite junior tennis players nationally ranked in the German Tennis Federation between 10 and 18 years participated in the study. According to their age at peak height velocity (PHV), players were divided into pre-PHV, circa-PHV, and post-PHV groups. SMP were derived from instantaneous time-velocity data of two 20 m all-out LS measured with 333 Hz. Further, mean values from two Tm505 trials with constant 3 kg loading over acceleration-deceleration (1a) and reacceleration (1b) phases were measured with an MRD. SMP of LS and CoD measurements were partially correlated with the current RP in the overall national ranking by controlling for biological maturation. Results Low to moderate correlations (rs = -0.1 to -0.3) were found between SMP and the RP in all male and female age groups. Correlations of the CoD measurements were overall more pronounced, particularly in girls (rs = -0.44). All linear SMP, like maximal theoretical force (F0; N/kg), and maximal theoretical velocity (v0; m/s), maximal power (Pmax; W/kg), improved over maturation for both genders with Pmax being most important for sprint performance. Further, Pmax was shown to correlate with the girls ranking position (rs = -0.31). During the Tm505, matured players achieved significantly faster overall total and CoD times. Positioning of CoM before CoD enlarged over maturation and was found to correlate to the RP in both sexes. In addition, nearly all SMP significantly correlated to the primary performance outcomes in the Tm505 test in both genders (r = -0.3 to -0.6). Conclusion CoD performance has a moderate and higher impact on tennis performance compared to LS. CoD performance as well as Pmax achieved a higher relevance for the ranking position predominantly in girls compared to boys. Hence, particularly Pmax as well as the transfer to on-court CoD motor skills should be a central training goal in elite junior tennis players besides technical skills and should depend on maturation status and gender.
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Affiliation(s)
- Nicola Reiner Volk
- Department of Training and Exercise Science, Faculty of Sport Science, Ruhr University Bochum, Bochum, Germany
| | - Jo-Lâm Vuong
- Department of Training and Exercise Science, Faculty of Sport Science, Ruhr University Bochum, Bochum, Germany
| | - Alexander Ferrauti
- Department of Training and Exercise Science, Faculty of Sport Science, Ruhr University Bochum, Bochum, Germany
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