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1.
J Ind Microbiol Biotechnol ; 50(1)2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-37960978

RESUMO

Gas chromatography-tandem mass spectrometry with electron ionization (GC-EI-MS/MS) provides rich information on stable-isotope labeling for 13C-metabolic flux analysis (13C-MFA). To pave the way for the routine application of tandem MS data for metabolic flux quantification, we aimed to compile a comprehensive library of GC-EI-MS/MS fragments of tert-butyldimethylsilyl (TBDMS) derivatized proteinogenic amino acids. First, we established an analytical workflow that combines high-resolution gas chromatography-quadrupole time-of-flight mass spectrometry and fully 13C-labeled biomass to identify and structurally elucidate tandem MS amino acid fragments. Application of the high-mass accuracy MS procedure resulted into the identification of 129 validated precursor-product ion pairs of 13 amino acids with 30 fragments being accepted for 13C-MFA. The practical benefit of the novel tandem MS data was demonstrated by a proof-of-concept study, which confirmed the importance of the compiled library for high-resolution 13C-MFA. ONE SENTENCE SUMMARY: An analytical workflow that combines high-resolution mass spectrometry (MS) and fully 13C-labeled biomass to identify and structurally elucidate tandem MS amino acid fragments, which provide positional information and therefore offering significant advantages over traditional MS to improve 13C-metabolic flux analysis.


Assuntos
Escherichia coli , Espectrometria de Massas em Tandem , Espectrometria de Massas em Tandem/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Escherichia coli/metabolismo , Isótopos de Carbono/análise , Isótopos de Carbono/metabolismo , Análise do Fluxo Metabólico/métodos , Aminoácidos/metabolismo
2.
Biology (Basel) ; 12(4)2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-37106731

RESUMO

(1) Background: Aging is linked to an altered immune response and metabolism. Inflammatory conditions, such as sepsis, COVID-19, and steatohepatitis are more prevalent in the elderly and steatosis is linked both to severe COVID-19 and sepsis. We hypothesized that aging is linked to a loss of endotoxin tolerance, which normally protects the host from excessive inflammation, and that this is accompanied by elevated levels of hepatic lipids. (2) Methods: An in vivo lipopolysaccharide (LPS) tolerance model in young and old mice was used and the cytokine serum levels were measured by ELISA. Cytokine and toll-like receptor gene expression was determined by qPCR in the lungs and the liver; hepatic fatty acid composition was assessed by GC-MS. (3) Results: The old mice showed a distinct potential for endotoxin tolerance as suggested by the serum cytokine levels and gene expression in the lung tissue. Endotoxin tolerance was less pronounced in the livers of the aged mice. However, the fatty acid composition strongly differed in the liver tissues of the young and old mice with a distinct change in the ratio of C18 to C16 fatty acids. (4) Conclusions: Endotoxin tolerance is maintained in advanced age, but changes in the metabolic tissue homeostasis may lead to an altered immune response in old individuals.

3.
Sports Biomech ; 22(1): 91-101, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34323653

RESUMO

Classification algorithms determine the similarity of an observation to defined classes, e.g., injured or healthy athletes, and can highlight treatment targets or assess progress of a treatment. The primary aim was to cross-validate a previously developed classification algorithm using a different sample, while a secondary aim was to examine its ability to predict future ACL injuries. The examined outcome measure was 'healthy-limb' class membership probability, which was compared between a cohort of athletes without previous or future (No Injury) previous (PACL) and future ACL injury (FACL). The No Injury group had significantly higher probabilities than the PACL (p < 0.001; medium effect) and FACL group (p ≤ 0.045; small effect). The ability to predict group membership was poor for the PACL (area under curve [AUC]; 0.61

Assuntos
Lesões do Ligamento Cruzado Anterior , Traumatismos em Atletas , Humanos , Ligamento Cruzado Anterior , Traumatismos em Atletas/diagnóstico , Fenômenos Biomecânicos , Aprendizado de Máquina , Algoritmos
4.
Sci Med Footb ; 7(4): 374-383, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-35896059

RESUMO

PURPOSE: The purpose of this study was to assess the agreement between match-derived running load outputs; total distance (TD), high-speed running (HSR) and sprint distance (SPR) obtained by two optical tracking systems. METHODS: Data were collected from 31 elite footballers from the first team and under-21 squads of an English Premier League (EPL) football club across three competitive matches. One EPL game (game 2) and one under-21 Premier League game (game 3) were played at the team's home stadium and one EPL game (game 1) at an away venue. All matches were tracked concomitantly using eight colour cameras sampling at 10 Hz (PROZONE®) and six high-definition motion cameras sampling at 25 Hz (TRACAB®). RESULTS: TD displayed a perfect (r = 0.99) correlation while HSR and SPR displayed very large (r = 0.81 and r = 0.73) correlations between TRACAB® and PROZONE®. Mean biases were 5% for TD, -3% for HSR and 61% for SPR. Between games, mean biases for TD were 6% for game 1, and 5% for game 2 and game 3. For HSR, 9% for game 1, -5% for game 2 and 6% for game 3 and for SPR, 31% for game 1, 71% for game 2 and 84% for game 3. CONCLUSION: TD and HSR can be interchanged between PROZONE® and TRACAB®, to allow accurate interpretation between the two optical systems. PROZONE® overestimated SPR compared to the TRACAB®, with the magnitude of difference considered meaningful, altering interpretation of historical match outputs, sprint volume trends in the EPL and forecasts of the modern game.


Assuntos
Desempenho Atlético , Futebol Americano , Corrida , Movimento (Física)
5.
Orthop J Sports Med ; 10(10): 23259671221125159, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36338351

RESUMO

Background: Athletic groin pain (AGP) can lead to altered movement patterns during rapid deceleration and acceleration. However, the effect of AGP on movement variability and loading patterns during such actions remains less clear. Purpose: To investigate, using a continuous lateral hurdle hop task, how movement variability and magnitude measures of 3-dimensional (3D) kinematic, kinetic, and vertical ground-reaction force (vGRF) variables are (1) affected by AGP (AGP vs uninjured controls [CON]) and (2) changed after successful rehabilitation (AGP prerehabilitation vs AGP postrehabilitation vs CON). Study Design: Controlled laboratory study. Methods: A total of 36 athletes diagnosed with AGP and 36 uninjured CON athletes matched on age (18-35 years), level (subelite), and type of sports played (multidirectional field sport) performed a continuous lateral hurdle hop test that involved 10 side-to-side hops over a 15-cm hurdle. The 3D joint kinematic, kinetic, and vGRF variables (total, eccentric, and concentric; ground contact time, peak force, and impulse; and eccentric rate of force development) were examined. The AGP and CON groups were tested at baseline, and the AGP group was retested after participants successfully completed a standardized, exercise-based rehabilitation program targeting intersegmental control. Results: There were no differences in baseline characteristics between the AGP (mean ± SD: age, 27.5 ± 4.8 years; height, 179.8 ± 6.3 cm; mass, 80.3 ± 7.1 kg) and CON (mean ± SD: age, 24.1 ± 4.5 years; height, 181.0 ± 5.8 cm; mass, 80.4 ± 8.2 kg) groups. At baseline, athletes with AGP demonstrated altered loading patterns in the vGRF (longer ground contact times, reduced peak force, and reduced rate of force development) compared with CON athletes, while no significant difference in any movement variability variables was evident. After rehabilitation, the athletes with AGP demonstrated significant changes in transverse and coronal plane hip and trunk kinematics, with no significant differences in vGRF variables compared with the CON group. Conclusion: The differences in baseline vGRF measures between the AGP and CON groups were no longer evident after athletes with AGP underwent rehabilitation. No differences in movement variability were evident between the AGP and CON groups, either before or after rehabilitation. Clinical Relevance: Rehabilitation programs should consider targeting intersegmental hip and trunk movement patterns to positively influence loading patterns in athletes with AGP.

6.
J Sports Sci ; 40(17): 1885-1900, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36093680

RESUMO

Injury assessment during sporting collisions requires estimation of the associated kinematics. While marker-based solutions are widely accepted as providing accurate and reliable measurements, setup times are lengthy and it is not always possible to outfit athletes with restrictive equipment in sporting situations. A new generation of markerless motion capture based on deep learning techniques holds promise for enabling measurement of movement in the wild. The aim of this work is to evaluate the performance of a popular deep learning model "out of the box" for human pose estimation, on a dataset of ten staged rugby tackle movements performed in a marker-based motion capture laboratory with a system of three high-speed video cameras. An analysis of the discrepancy between joint positions estimated by the marker-based and markerless systems shows that the deep learning approach performs acceptably well in most instances, although high errors exist during challenging intervals of heavy occlusion and self-occlusion. In total, 75.6% of joint position estimates are found to have a mean absolute error (MAE) of less than or equal to 25 mm, 17.8% with MAE between 25 and 50 mm and 6.7% with MAE greater than 50 mm. The mean per joint position error is 47 mm.


Assuntos
Aprendizado Profundo , Esportes , Humanos , Movimento (Física) , Fenômenos Biomecânicos , Movimento
7.
Scand J Med Sci Sports ; 32(5): 924-932, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35108419

RESUMO

OBJECTIVE: Hip and groin pain is highly prevalent in sub-elite Gaelic Athletic Association (GAA) athletes, but its prevalence at the elite level is unknown. The aims of this study were to report hip and groin pain prevalence in elite male athletes, to report changes in Copenhagen Hip and Groin Outcome Score (HAGOS) across two seasons and to assess if previous hip and groin pain or pre-season HAGOS could predict future hip and groin pain. METHODS: During the 2017 and 2018 pre-season male Gaelic Players Association (GPA) playing members were invited to complete two questionnaires. The first questionnaire collected demographic information including age, GAA code played (Gaelic football or Hurling) and prevalence of hip and groin pain in the previous season. The second questionnaire was the HAGOS. Step-wise logistic regression models were fitted to HAGOS subscales, to examine if pre-season HAGOS subscale scores could predict future hip and groin pain. RESULTS: The prevalence of hip and groin pain across the elite GAA cohort was 38%. Hip and groin pain in the previous season was the strongest predictor of future hip and groin pain (r2 =0.19, AUC=0.73, 95% CI 1.76-2.27) whereas pre-season HAGOS subscale scores had limited and no additional predictive ability (AUC 0.05-0.18). CONCLUSIONS: Hip and groin pain prevalence is high in elite male GAA, with one in three athletes reporting pain. Previous season hip and groin pain is the strongest predictor of future hip and groin pain, while pre-season HAGOS scores have limited ability to predict future hip and groin pain.


Assuntos
Virilha , Quadril , Humanos , Masculino , Dor/epidemiologia , Prevalência , Estações do Ano
8.
J Strength Cond Res ; 36(3): 772-780, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32058359

RESUMO

ABSTRACT: Ó Catháin, CP, Richter, C, and Moran, K. Can directed compliant running reduce the magnitude of variables associated with the development of running injuries? J Strength Cond Res 36(3): 772-780, 2022-Running is one of the most popular modes of activity worldwide and provides numerous health benefits. However, impact forces associated with the foot contacting the ground have been implicated in the development of running related injuries. As such, previous studies have used various methods to alter running to reduce the magnitude of these impact forces. However, it is unclear what kinematic changes facilitate this reduced loading or how loading further up the body changes. In this study, verbal direction was used to teach subjects to run with a more compliant running technique. Kinetic and kinematics characteristics of each subjects "normal" running technique and new "compliant technique" were measured in a fatigued and unfatigued state. Energy expenditure of each running style was also measured. Verbally directed compliant running significantly decreased (17%) vertical ground reaction force impact peaks, sacral (41%) and head (28%) impact accelerations, and increased energy expenditure (21%), in comparison with normal running. Findings suggest that verbally directed compliant running may reduce the magnitude of variables associated with the development of running injuries.


Assuntos
Corrida , Aceleração , Fenômenos Biomecânicos , , Humanos , Extremidade Inferior , Corrida/lesões
9.
Am J Sports Med ; 49(11): 2994-3003, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34398640

RESUMO

BACKGROUND: Exercise-based rehabilitation targeting intersegmental control has high success rates and fast recovery times in the management of athletic groin pain (AGP). The influence of this approach on hip strength and lower limb reactive strength and how these measures compare with uninjured athletes (CON) remain unknown. Additionally, the efficacy of this program after return to play (RTP) has not been examined. PURPOSE: First, to examine differences in isometric hip strength, reactive strength, and the Hip and Groin Outcome Score (HAGOS) between the AGP and CON cohorts and after rehabilitation; second, to examine the relationship between the change in HAGOS and the change in strength variables after rehabilitation; last, to track HAGOS for 6 months after RTP. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: A total of 42 athletes diagnosed with AGP and 36 matched controls completed baseline testing: isometric hip strength, lower limb reactive strength, and HAGOS. After rehabilitation, athletes with AGP were retested, and HAGOS was collected at 3 and 6 months after RTP. RESULTS: In total, 36 athletes with AGP completed the program with an RTP time of 9.8 ± 3.0 weeks (mean ± SD). At baseline, these athletes had significantly lower isometric hip strength (abduction, adduction, flexion, extension, external rotation: d = -0.67 to -1.20), single-leg reactive strength (d = -0.73), and HAGOS (r = -0.74 to -0.89) as compared with the CON cohort. Hip strength (d = -0.83 to -1.15) and reactive strength (d = -0.30) improved with rehabilitation and were no longer significantly different between groups at RTP. HAGOS improvements were maintained or improved in athletes with AGP up to 6 months after RTP, although some subscales remained significantly lower than the CON group (r = -0.35 to -0.51). Two linear regression features (hip abduction and external rotation) explained 11% of the variance in the HAGOS Sports and Recreation subscale. CONCLUSION: Athletes with AGP demonstrated isometric hip strength and reactive strength deficits that resolved after an intersegmental control rehabilitation program; however, improved hip strength explained only 11% of improvement in the Sports and Recreation subscale. HAGOS improvements after pain-free RTP were maintained at 6 months.


Assuntos
Virilha , Esportes , Estudos de Coortes , Humanos , Força Muscular , Dor
12.
Am J Sports Med ; 49(4): 918-927, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33617291

RESUMO

BACKGROUND: Performance measures such as strength, jump height/length, and change of direction (CoD) time during anterior cruciate ligament (ACL) rehabilitation have been used to determine readiness to return to play and identify those who may be at risk of rerupture. However, athletes may reach these criteria despite ongoing biomechanical deficits when performing these tests. Combining return-to-play criteria with an assessment of movement through 3-dimensional (3D) biomechanics in male field sports athletes to identify risk factors for ACL rerupture has not been explored previously. PURPOSE: To prospectively examine differences in strength, jump, and CoD performance and movement using 3D biomechanics in a cohort of male athletes playing level 1 sports (ie, multidirectional field sports that involve landing, pivoting, or CoD) between those who reinjured the reconstructed ACL (RI group) and those with no reinjury (NRI group) after 2 years of follow-up and to examine the ability of these differences to predict reinjury. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: After primary ACL reconstruction (ACLR), 1045 male athletes were recruited and underwent testing 9 months after surgery including isokinetic strength, jump, and CoD performance measures as well as patient-reported outcomes and 3D biomechanical analyses. Participants were followed up after 2 years regarding ACL reinjury status. Differences were determined between the RI and NRI groups in patient-reported outcomes, performance measures, and 3D biomechanics on the ACLR side and symmetry between limbs. The ability of these measures to predict ACL reinjury was determined through logistic regression. RESULTS: No differences were identified in strength and performance measures on the ACLR side or in symmetry. Biomechanical analysis indicated differences on the ACLR side primarily in the sagittal plane for the double-leg drop jump (effect size, 0.59-0.64) and greater asymmetry primarily in the frontal plane during unplanned CoD (effect size, 0.61-0.69) in the RI group. While these biomechanical test results were different between groups, multivariate regression modeling demonstrated limited ability (area under the curve, 0.67 and 0.75, respectively) to prospectively predict ACL reinjury. CONCLUSION: Commonly reported return-to-play strength, jump, and timed CoD performance measures did not differ between the RI and NRI groups. Differences in movement based on biomechanical measures during double-leg drop jump and unplanned CoD were identified, although they had limited ability to predict reinjury. Targeting these variables during rehabilitation may reduce reinjury risk in male athletes returning to level 1 sports after ACLR. REGISTRATION: NCT02771548 (ClinicalTrials.gov identifier).


Assuntos
Lesões do Ligamento Cruzado Anterior , Relesões , Ligamento Cruzado Anterior , Lesões do Ligamento Cruzado Anterior/cirurgia , Atletas , Fenômenos Biomecânicos , Estudos de Coortes , Humanos , Masculino , Volta ao Esporte
13.
Am J Sports Med ; 49(3): 609-619, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33560866

RESUMO

BACKGROUND: Athletes are twice as likely to rupture the anterior cruciate ligament (ACL) on their healthy contralateral knee than the reconstructed graft after ACL reconstruction (ACLR). Although physical testing is commonly used after ACLR to assess injury risk to the operated knee, strength, jump, and change-of-direction performance and biomechanical measures have not been examined in those who go on to experience a contralateral ACL injury, to identify factors that may be associated with injury risk. PURPOSE: To prospectively examine differences in biomechanical and clinical performance measures in male athletes 9 months after ACLR between those who ruptured their previously uninjured contralateral ACL and those who did not at 2-year follow-up and to examine the ability of these differences to predict contralateral ACL injury. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: A cohort of male athletes returning to level 1 sports after ACLR (N = 1045) underwent isokinetic strength testing and 3-dimensional biomechanical analysis of jump and change-of-direction tests 9 months after surgery. Participants were followed up at 2 years regarding return to play or at second ACL injury. Between-group differences were analyzed in patient-reported outcomes, performance measures, and 3-dimensional biomechanics for the contralateral limb and asymmetry. Logistic regression was applied to determine the ability of identified differences to predict contralateral ACL injury. RESULTS: Of the cohort, 993 had follow-up at 2 years (95%), with 67 experiencing a contralateral ACL injury and 38 an ipsilateral injury. Male athletes who had a contralateral ACL injury had lower quadriceps strength and biomechanical differences on the contralateral limb during double- and single-leg drop jump tests as compared with those who did not experience an injury. Differences were related primarily to deficits in sagittal plane mechanics and plyometric ability on the contralateral side. These variables could explain group membership with fair to good ability (area under the curve, 0.74-0.80). Patient-reported outcomes, limb symmetry of clinical performance measures, and biomechanical measures in change-of-direction tasks did not differentiate those at risk for contralateral injury. CONCLUSION: This study highlights the importance of sagittal plane control during drop jump tasks and the limited utility of limb symmetry in performance and biomechanical measures when assessing future contralateral ACL injury risk in male athletes. Targeting the identified differences in quadriceps strength and plyometric ability during late-stage rehabilitation and testing may reduce ACL injury risk in healthy limbs in male athletes playing level 1 sports. CLINICAL RELEVANCE: This study highlights the importance of assessing the contralateral limb after ACLR and identifies biomechanical differences, particularly in the sagittal plane in drop jump tasks, that may be associated with injury to this limb. These factors could be targeted during assessment and rehabilitation with additional quadriceps strengthening and plyometric exercises after ACLR to potentially reduce the high risk of injury to the previously healthy knee. REGISTRATION: NCT02771548 (ClinicalTrials.gov identifier).


Assuntos
Lesões do Ligamento Cruzado Anterior , Reconstrução do Ligamento Cruzado Anterior , Lesões do Ligamento Cruzado Anterior/cirurgia , Atletas , Fenômenos Biomecânicos , Estudos de Casos e Controles , Humanos , Masculino , Volta ao Esporte
14.
PLoS One ; 16(2): e0246510, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33592061

RESUMO

Metabolites play a key role in plants as they are routing plant developmental processes and are involved in biotic and abiotic stress responses. Their analysis can offer important information on the underlying processes. Regarding plant breeding, metabolite concentrations can be used as biomarkers instead of or in addition to genetic markers to predict important phenotypic traits (metabolic prediction). In this study, we applied a genome-wide association study (GWAS) in a wild barley nested association mapping (NAM) population to identify metabolic quantitative trait loci (mQTL). A set of approximately 130 metabolites, measured at early and late sampling dates, was analysed. For four metabolites from the early and six metabolites from the late sampling date significant mQTL (grouped as 19 mQTL for the early and 25 mQTL for the late sampling date) were found. Interestingly, all of those metabolites could be classified as sugars. Sugars are known to be involved in signalling, plant growth and plant development. Sugar-related genes, encoding mainly sugar transporters, have been identified as candidate genes for most of the mQTL. Moreover, several of them co-localized with known flowering time genes like Ppd-H1, HvELF3, Vrn-H1, Vrn-H2 and Vrn-H3, hinting on the known role of sugars in flowering. Furthermore, numerous disease resistance-related genes were detected, pointing to the signalling function of sugars in plant resistance. An mQTL on chromosome 1H in the region of 13 Mbp to 20 Mbp stood out, that alone explained up to 65% of the phenotypic variation of a single metabolite. Analysis of family-specific effects within the diverse NAM population showed the available natural genetic variation regarding sugar metabolites due to different wild alleles. The study represents a step towards a better understanding of the genetic components of metabolite accumulation, especially sugars, thereby linking them to biological functions in barley.


Assuntos
Estudo de Associação Genômica Ampla/métodos , Hordeum/genética , Alelos , Flores/genética , Genoma de Planta/genética , Genótipo , Fenótipo , Melhoramento Vegetal , Polimorfismo de Nucleotídeo Único/genética , Locos de Características Quantitativas/genética
15.
J Strength Cond Res ; 35(6): 1715-1723, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30664108

RESUMO

ABSTRACT: Welch, N, Richter, C, Franklyn-Miller, A, and Moran, K. Principal component analysis of the biomechanical factors associated with performance during cutting. J Strength Cond Res 35(6): 1715-1723, 2021-The main aim of the current study was to investigate the relationship between kinematic variables in cutting and performance outcome across different angled cuts through the use of principal component analysis and permutation testing. Twenty-five male intercounty Gaelic football players (23.5 ± 4.2 years, 183 ± 6 cm, and 83 ± 6.9 kg) participated in the study. Three-dimensional motion capture was used to perform a biomechanical analysis of 110 and 45° cutting tasks. Principal component analysis and permutation testing revealed one principal component within the 45° cut (r = 0.26) and 2 principal components within the 110° (r = 0.66 and 0.27) cut that consistently correlated with performance outcome. Within the 45° cut, the identified principal component was interpreted as relating to performance cues of maintaining a low center of mass during the concentric phase, using a shorter ground contact time, resisting a reduction in lateral center of mass to ankle and knee distance in the eccentric phase, and using faster and larger extensions of the hip and knee. Within the 110° cut, the first identified principal component was interpreted as relating to performance cues of maintaining a low center of mass during the concentric phase, using a shorter ground contact time, resisting a reduction in lateral center of mass to ankle and knee distance in the eccentric phase, and resisting hip flexion then using hip extension. The second principal component was interpreted as relating to a performance cue of leaning in the direction of the cut.


Assuntos
Desempenho Atlético , Movimento , Humanos , Masculino , Fenômenos Biomecânicos , Articulação do Joelho , Análise de Componente Principal , Esportes de Equipe , Desempenho Atlético/fisiologia
16.
J Strength Cond Res ; 35(7): 1848-1855, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30741857

RESUMO

ABSTRACT: Welch, N, Richter, C, Moran, K, and Franklyn-Miller, A. Principal component analysis of the associations between kinetic variables in cutting and jumping, and cutting performance outcome. J Strength Cond Res 35(7): 1848-1855, 2021-The primary aim of this study was to determine which features within the ground reaction force (GRF) trace during cutting are related to performance outcome in different angled cuts. The secondary aim was to understand the relationship between GRF features in a series of maximum strength, explosive strength, and reactive strength tests, and cutting performance outcome. Twenty-five male intercounty Gaelic football players (23.5 ± 4.2 years, 183 ± 6 cm, and 83 ± 6.9 kg) participated in the study. Subjects completed 110 and 45° cutting tasks, single leg squat jumps, drop landings, drop jumps, and isometric midthigh pulls. A principal component (PC) analysis and simulation approach were applied to the data and correlations between PCs and cutting performance outcome measured. Lower vertical to horizontal impulse ratios (r = -0.70 to -0.46) in both cuts and greater forces over the first 50 ms of ground contact (r = -0.44) in the 110° cut correlated with enhanced cutting performance outcomes. Greater reactive strength index and height in the drop jump (r = -0.51 and -0.54) and greater impulses over the first 25 ms of ground contact in the drop landing (r = 0.49 and 0.70) correlated with enhanced cutting performance outcomes. These results highlight the importance of greater horizontal and rapid force production in cutting and greater reactive strength qualities to enhance cutting performance.


Assuntos
Desempenho Atlético , Esportes de Equipe , Humanos , Masculino , Cinética , Postura , Análise de Componente Principal , Desempenho Atlético/fisiologia
17.
Sci Med Footb ; 5(sup1): 26-31, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-35077322

RESUMO

The COVID-19 pandemic forced elite football leagues into extended breaks followed by prompt resumption of competition. Inadequate periods of on-pitch football-specific training may underlie the increased injury incidence reported following restart in a non-peer reviewed report. Detraining effects from isolated training are expected, but existing models do not completely describe the unprecedented conditions imposed by COVID-19.Providing insight into specific neuromuscular qualities affected by extended absence of football-specific training, we share countermovement jump performance and kinetic data from an elite team's assessments pre and post 15 weeks of isolated training, and to contextualise these trends, off-season changes with no training.The isolated circuit resistance and aerobic interval training maintained jump height and Reactive Strength Indexmodified, but there were moderate magnitude (p = 0.01-0.04) changes in eccentric 'yielding' and landing 'loading' phase variables. These changes suggest a compromised initiation of countermovement deceleration, impact attenuation and altered coordination/motor control strategies or muscle-tendon properties. This analysis may have revealed kinetic markers specifically stimulated by football-specific training/competition, relevant to post-quarantine monitoring. Lower landing forces may reduce overuse injury risk, while yielding phase alterations suggest a negative effect on reactive performance, therefore the overall effect on vulnerability to injury is unclear.


Assuntos
Desempenho Atlético , COVID-19 , Humanos , Pandemias , Quarentena , SARS-CoV-2
18.
Scand J Med Sci Sports ; 31(4): 839-847, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33098142

RESUMO

Athletic groin pain (AGP) is a chronic, painful condition which is prevalent in players of field sports that require rapid changes of direction. Following successful rehabilitation, systematic changes have been observed in the kinetics and kinematics of pre-planned change of direction maneuvers, providing insight into potential foci for rehabilitation monitoring and for the assessment of interventions. However, changing direction in field sports is often reactive rather than pre-planned, and it is not known whether such post-rehabilitation changes are seen in reactive maneuvers. We analyzed the stance phase kinetics and kinematics of a 90° reactive cutting maneuver in 35 AGP patients before and after a successful exercise intervention program. Following the intervention, transverse plane rotation of the pelvis toward the intended direction of travel increased, and the body center of mass was positioned more anteriorly relative to the center of pressure. Ankle dorsiflexion also increased, and participants demonstrated greater ankle plantar flexor internal moment and power during the second half of stance. These findings provide insight into mechanical variables of potential importance in AGP, as identified during a maneuver based on a common sporting task.


Assuntos
Traumatismos em Atletas/reabilitação , Virilha/lesões , Movimento/fisiologia , Corrida/fisiologia , Adulto , Fenômenos Biomecânicos , Humanos , Cinética , Masculino , Adulto Jovem
19.
BMJ Open Sport Exerc Med ; 6(1): e000899, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33304604

RESUMO

OBJECTIVES: The main aim in the current study was to use a single-subject analysis to profile the physical performance characteristics of individuals within an injured group and a between-group approach to profile the group as a whole. These profiles were then used to inform single-subject and between-group rehabilitation interventions. METHODS: Fifty-three (28 with athletic groin pain and 25 non-injured) Gaelic football players (24.8 years±7.1 years; 179 cm±5.5 cm; 79.7 kg±9.2 kg) underwent 3D biomechanical analysis, which was used to measure a series of physical performance characteristics. The non-injured group was used to create a 'performance database' to compare the injured individuals, and a between-group analysis was also conducted. The scores from each analysis were used to inform the targets of interventions. RESULTS: The analysis highlighted the variety of profiles that existed across the tested individuals and that these profiles differed from that of the between-group analysis. By analysing individuals in a single-subject approach, detail can be seen that is lost with between-group analysis.

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