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1.
Br J Cancer ; 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38704477

RESUMO

The COVID-19 pandemic brought unplanned service disruption for breast cancer diagnostic, treatment and support services. This scoping review describes these changes and their impact in the UK and the Republic of Ireland based on studies published between January 2020 and August 2023. Thirty-four of 569 papers were included. Data were extracted and results thematically organized. Findings include fewer new cases; stage shift (fewer early- and more late-stage disease); and changes to healthcare organization, breast screening and treatment. Examples are accepting fewer referrals, applying stricter referral criteria and relying more on virtual consultations and multi-disciplinary meetings. Screening service programs paused during the pandemic before enacting risk-based phased restarts with longer appointment times to accommodate reduced staffing numbers and enhanced infection-control regimes. Treatments shifted from predominantly conventional to hypofractionated radiotherapy, fewer surgical procedures and increased use of bridging endocrine therapy. The long-term impact of such changes are unknown so definitive guidelines for future emergencies are not yet available. Cancer registries, with their large sample sizes and population coverage, are well placed to monitor changes to stage and survival despite difficulties obtaining definitive staging during diagnosis because surgery and pathological assessments are delayed. Multisite longitudinal studies can also provide guidance for future disaster preparedness.

2.
Br J Surg ; 111(1)2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-37930678

RESUMO

BACKGROUND: The aim of this multicentre prospective audit was to describe the current practice in the management of mastitis and breast abscesses in the UK and Ireland, with a specific focus on rates of surgical intervention. METHODS: This audit was conducted in two phases from August 2020 to August 2021; a phase 1 practice survey and a phase 2 prospective audit. Primary outcome measurements for phase 2 included patient management pathway characteristics and treatment type (medical/radiological/surgical). RESULTS: A total of 69 hospitals participated in phase 2 (1312 patients). The key findings were a high overall rate of incision and drainage (21.0 per cent) and a lower than anticipated proportion of ultrasound-guided aspiration of breast abscesses (61.0 per cent). Significant variations were observed regarding the rate of incision and drainage (range 0-100 per cent; P < 0.001) and the rate of needle aspiration (range 12.5-100 per cent; P < 0.001) between individual units. Overall, 22.5 per cent of patients were admitted for inpatient treatment, out of whom which 72.9 per cent were commenced on intravenous antibiotics. The odds of undergoing incision and drainage for a breast abscess or being admitted for inpatient treatment were significantly higher if patients presented at the weekend compared with a weekday (P ≤ 0.023). Breast specialists reviewed 40.9 per cent of all patients directly, despite the majority of patients (74.2 per cent) presenting within working hours on weekdays. CONCLUSIONS: Variation in practice exists in the management of mastitis and breast abscesses, with high rates of incision and drainage in certain regions of the UK. There is an urgent need for a national best-practice toolbox to minimize practice variation and standardize patient care.


Mastitis and breast abscess is a painful infection of the breast. It is an extremely common breast problem. One in three women can get this condition at some stage in their life. To treat a breast abscess, the pus inside should be drained out of the body. This can be done either by cutting into the breast using surgery or by inserting a fine needle using an ultrasonography scan (which uses ultrasound). Fine-needle drainage has the benefit that it does not require admission to hospital. Surgery can cause the breast to look misshapen. It is unknown which method is used more often in the UK and Ireland. The aim of this study was to describe how mastitis and breast abscesses are treated in the UK and Ireland. This study involved a survey of practice (phase 1) and collection of data, which are routinely recorded for these patients (phase 2). This study involved 69 hospitals and 1312 patient records. One in five women had an operation for a breast abscess. This was higher than expected. Six in 10 women had a pus drainage using a fine needle. The chance of having an operation depended on the hospital. Women that came to hospital at the weekend were almost twice as likely to have an operation. One in five women were admitted to hospital. The chances of that more than doubled if a woman came to hospital at the weekend. There are differences in treatment of mastitis and breast abscesses across the UK and Ireland. Changes need to be put in place to make access to treatment more equal.


Assuntos
Doenças Mamárias , Mastite , Feminino , Humanos , Abscesso/cirurgia , Doenças Mamárias/cirurgia , Irlanda/epidemiologia , Mastite/terapia , Drenagem , Reino Unido/epidemiologia
3.
J Sports Sci ; 41(10): 1008-1017, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37724819

RESUMO

Chronological age classifies elite male gymnasts into developmental performance classifications: senior (18+ years), junior (14-18 years) and development (8-14 years). Here, we examine the influence of age and experience on the biomechanics of the high bar longswing across classifications. Joint angular kinematics and kinetics were obtained from 30 gymnasts performing three sets each of eight consecutive longswings. Differences between groups and relations between age, experience and key biomechanical variables were correlated. Kinetic variables and range of motion of the hip and knee were highest for development gymnasts. In all age groups, a dominant shoulder kinetic contribution was found, although circle location of the peak joint kinetics occurred earliest for junior gymnasts. Hip work contributed more prominently in development gymnasts. Age and experience were positively correlated to an increase in peak shoulder moments and powers and negatively correlated to peak hip and knee moments. The findings reveal that age and experience combine to influence the functional phase, joint kinematics and relative joint kinetic contribution, particularly with the senior group demonstrating a shoulder dominant technique. Changes in musculoskeletal loading across the age groups suggest that factors such as relative strength and practice may have influenced this joint mode transition of the longswing.


Assuntos
Ginástica , Ombro , Humanos , Masculino , Adolescente , Fenômenos Biomecânicos , Articulação do Joelho
4.
Biology (Basel) ; 12(8)2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37626975

RESUMO

BACKGROUND: Taking part in moderate-to-vigorous exercise in contact sports on a regular basis may be linked to an increase in cerebrovascular injury and head trauma. Validated objective measures are lacking in the initial post-event diagnosis of head injury. The exercise style, duration, and intensity may also confound diagnostic indicators. As a result, we propose that the new Interdisciplinary Group in Movement & Performance from Acute & Chronic Head Trauma (IMPACT) analyze a variety of functional (biomechanical and motor control) tests as well as related biochemistry to see how they are affected by contact in sports and head injury. The study's goal will be to look into the performance and physiological changes in rugby players after a game for head trauma and injury. METHODS: This one-of-a-kind study will use a randomized controlled trial (RCT) utilizing a sport participation group and a non-participation control group. Forty male rugby 7 s players will be recruited for the study and allocated randomly to the experimental groups. The intervention group will participate in three straight rugby matches during a local 7 s rugby event. At the pre-match baseline, demographic and anthropometric data will be collected. This will be followed by the pre-match baseline collection of biochemical, biomechanical, and cognitive-motor task data. After three consecutive matches, the same measures will be taken. During each match, a notational analysis will be undertaken to obtain contact information. All measurements will be taken again 24, 48, and 72 h after the third match. DISCUSSION: When the number of games increases owing to weariness and/or stressful circumstances, we expect a decline in body movement, coordination, and cognitive-motor tasks. Changes in blood biochemistry are expected to correspond to changes in biomechanics and cognitive-motor processes. This research proposal will generate considerable, ecologically valid data on the occurrence of head trauma events under game conditions, as well as the influence of these events on the biological systems of the performers. This will lead to a greater understanding of how sports participants react to exercise-induced injuries. This study's scope will have far-reaching ramifications for doctors, coaches, managers, scientists, and sports regulatory bodies concerned with the health and well-being of athletic populations at all levels of competition, including all genders and ages.

5.
J Sports Sci ; 41(6): 519-525, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37330666

RESUMO

This study investigated the short-term responses of step characteristics in sprinters and team-sports players under different bend conditions. Eight participants from each group completed 80 m sprints in four conditions: banked and flat, in lanes two and four (L2B, L4B, L2F, L4F). Groups showed similar changes in step velocity (SV) across conditions and limbs. However, sprinters produced significantly shorter ground contact times (GCT) than team sports players in L2B and L4B for both left (0.123 s vs 0.145 s and 0.123 s vs 0.140 s) and right steps (0.115 s vs 0.136 s and 0.120 s vs 0.141 s) (p > 0.001-0.029; ES = 1.15-1.37). Across both groups, SV was generally lower in flat conditions compared to banked (Left: 7.21 m/s vs 6.82 m/s and Right: 7.31 m/s vs 7.09 m/s in lane two), occurring due to reduced step length (SL) rather than step frequency (SF), suggesting that banking improves SV via increased SL. Sprinters produced significantly shorter GCT in banked conditions that led to non-significant increases in SF and SV, highlighting the importance of bend sprinting specific conditioning and training environments representative of indoor competition for sprint athletes.


Assuntos
Desempenho Atlético , Corrida , Humanos , Corrida/fisiologia , Esportes de Equipe , Rádio (Anatomia) , Fenômenos Biomecânicos , Extremidade Superior , Desempenho Atlético/fisiologia
6.
J Sports Sci ; 41(1): 27-35, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37031454

RESUMO

This study aimed to increase understanding of the biomechanics and dynamics of the upper limbs during the contact phase of the round-off (RO) performed using three techniques. Twenty female gymnasts performed six successful RO trials in each condition: parallel, T-shape and reverse. Kinetic and kinematic data were collected for each trial. All analyses focused on the contact phase for each hand. Continuous joint profiles examined the dynamics of these tasks as well as the kinetic sequencing. In each case, joint angles, angular velocity, moments and powers at the wrist and elbow joint were reported. Difference between the contact phases of the techniques was examined using a one-way ANOVA SPM. The T-shape technique demonstrated negative power at the wrist during contact; however, the elbow joint compensated with a significantly greater positive power generation during the propulsive phase, suggesting a more effective technique compared to the reduced powers of the reverse and parallel. The order of the peak joint powers during the contact phase, the reverse technique, demonstrated a proximal to distal sequence, in contrast to the distal to proximal for the other techniques. These findings highlight the task-specific coordinative structures during this closed chained action.


Assuntos
Articulação do Cotovelo , Ginástica , Humanos , Feminino , Fenômenos Biomecânicos , Extremidade Superior , Mãos
8.
J Hum Kinet ; 83: 13-21, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36157960

RESUMO

Single arm blocking is a key component of successful basketball defence. The player uses either their dominant or non-dominant arm to block the ball landing on a common leg. Understanding how the bio-physical loads of the landing leg change as a function of the blocking arm will provide insights into potential injury risk of the lower limb. The aim of this study was to investigate the effects of arm dominance on the biomechanical variables of injury risk of the lower limb, specifically the knee joint during the single-leg landing in female basketball players. Kinematic and kinetic data were collected from fourteen female basketball athletes (20.85 ± 1.35 years, 1.69 ± 0.06 m, 60.37 ± 7.75 kg), each performing three trials of a dominant arm and non-dominant block jump landing on the dominant leg. The results showed significantly higher anterior and medial ground reaction force, knee joint flexion and abduction and lateral knee force during the dominant arm landing (p < 0.05). These findings highlight potential injury risk and the need for the player to be more proficient at dominant arm block-shot landing. The player should aim to develop a larger landscape of technique to meet the demands of the game and facilitate a more effective and safer landing strategy.

9.
Entropy (Basel) ; 24(7)2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35885134

RESUMO

The preservation of static balance in both upright- and hand-stance is maintained by the projection of center of mass (CM) motion within the region of stability at the respective base of support. This study investigated, from a degrees of freedom (DF) perspective, whether the stability of the CM in both upright- and hand-stances was predicted by the respective dispersion and time-dependent regularity of joint (upright stance-ankle, knee, hip, shoulder, neck; hand stance-wrist, elbow, shoulder, neck) angle and position. Full body three-dimensional (3D) kinematic data were collected on 10 advanced level junior female gymnasts during 30 s floor upright- and hand-stands. For both stances the amount of the dispersion of joint angle and sway motion was higher than that of the CM and center of pressure (CP) with an inverse relation to time-dependent irregularity (SampEn). In upright-standing the variability of neck motion in the anterior-posterior direction was significantly greater than that of most joints consistent with the role of vision in the control of quiet upright posture. The findings support the proposition that there are both task specific and general properties to the global CM control strategy in the balance of upright- and hand-standing induced by the different active skeletal-muscular organization and the degeneracy revealed in the multiple distributional variability patterns of the joint angle and position in 3D.

11.
Cancer Res ; 82(5): 819-830, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35027467

RESUMO

Mutations in SF3B1 have been identified across several cancer types. This key spliceosome component promotes the efficient mRNA splicing of thousands of genes including those with crucial roles in the cellular response to DNA damage. Here, we demonstrate that depletion of SF3B1 specifically compromises homologous recombination (HR) and is epistatic with loss of BRCA1. More importantly, the most prevalent cancer-associated mutation in SF3B1, K700E, also affects HR efficiency and as a consequence, increases the cellular sensitivity to ionizing radiation and a variety of chemotherapeutic agents, including PARP inhibitors. In addition, the SF3B1 K700E mutation induced unscheduled R-loop formation, replication fork stalling, increased fork degradation, and defective replication fork restart. Taken together, these data suggest that tumor-associated mutations in SF3B1 induce a BRCA-like cellular phenotype that confers synthetic lethality to DNA-damaging agents and PARP inhibitors, which can be exploited therapeutically. SIGNIFICANCE: The cancer-associated SF3B1K700E mutation induces DNA damage via generation of genotoxic R-loops and stalled replication forks, defective homologous recombination, and increased replication fork degradation, which can be targeted with PARP inhibitors.


Assuntos
Neoplasias , Fosfoproteínas , Inibidores de Poli(ADP-Ribose) Polimerases , Fatores de Processamento de RNA , Replicação do DNA , Humanos , Mutação , Neoplasias/tratamento farmacológico , Neoplasias/genética , Fenótipo , Fosfoproteínas/genética , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Fatores de Processamento de RNA/genética , Mutações Sintéticas Letais
12.
Sports Biomech ; 21(9): 1021-1031, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32129721

RESUMO

Artificial turf (AT) is common at all levels of soccer and rugby. Employing an interdisciplinary design, this study aimed to examine the extent to which the negative attitude commonly expressed by players concerning AT is based on the difference in technique between AT and natural turf (NT), or due to pre-existing biases. Thirty professional soccer and rugby players performed a defined set of movements with masked and normal perception conditions on NT and AT. Two-dimensional kinematic analysis (100 Hz) of characteristics in parallel to a psychological assessment of the impact of cognitive bias for a playing surface was assessed. No significant interaction effects between the level of perception and surface type were found. For AT, contact time (CT) was shorter across conditions, while for NT rugby players had longer CT during acceleration/deceleration phases and shorter flight times. Pre-existing negative bias against AT was found during the normal perception trials in the technology acceptance model (Usefulness and Ease of Use) and the general preference questions on how much the athlete would like to play a game on it. The results suggest that opinion was not driven by surface characteristics, but by a cognitive bias, players brought with them to the pitch.


Assuntos
Futebol , Aceleração , Fenômenos Biomecânicos , Humanos , Percepção , Rugby
13.
Eur J Sport Sci ; 22(11): 1678-1685, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34570691

RESUMO

Inconsistencies between sexes in the landing criteria provided by the international gymnastics governing body (FIG) may predispose female gymnasts to lower extremity injury. This study aimed to investigate lower extremity biomechanics when performing the male and female landing strategy. Seven collegiate, female gymnasts (age: 20.5 ± 1.2 years, height: 1.64 ± 0.06 m, mass: 60.4 ± 10.2 kg) performed drop landings using the prescribed women's and men's landing strategy. Kinematic and kinetic data from 10 trials of each landing strategy were collected. Differences between landing strategy at individual and group level for key injury risk variables of the lower limb were explored. Group differences (p ≤ .05) were reported in the sagittal range of motion (ROM) at the knees and hips, with the men's landing strategy eliciting a larger ROM decelerating the body upon impact. Large inter and intra-individual variation was apparent with different movement responses shown across individuals and demonstrating degeneracy as gymnasts satisfied the overall landing objective. These results indicate an individually favoured landing strategy to fulfil the informational constraints and hence supporting the use of a single-subject design. The current study emphasises the potential injury risk associated with the different informational constraints placed on females' landing strategy by the FIG, whilst recognising the individual gymnasts' task response.Highlights An increase in the range of motion at the knee and hip may support the recommendation of the men's landing style.Gymnasts appear to utilise individual landing strategies to complete the landing objective, supporting the use of a single-subject design.


Assuntos
Articulação do Joelho , Extremidade Inferior , Feminino , Masculino , Humanos , Adulto Jovem , Adulto , Fenômenos Biomecânicos , Articulação do Joelho/fisiologia , Extremidade Inferior/fisiologia , Joelho/fisiologia , Ginástica/fisiologia , Movimento/fisiologia
14.
Sports Health ; 14(4): 500-507, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34558993

RESUMO

BACKGROUND: Greater neck strength is associated with fewer head and neck injuries. Neck-strengthening programs are commonly burdensome, requiring specialist equipment or significant time commitment, which are barriers to implementation. HYPOTHESIS: Completing a neck-strengthening program will increase isometric neck strength in age-group rugby players. STUDY DESIGN: A pilot randomized controlled exercise intervention study. LEVEL OF EVIDENCE: Level 2. METHODS: Twenty-eight U18 (under 18) male regional age-group rugby union players were randomized (intervention n =15/control n = 13). An 8-week exercise program was supervised during preseason at the regional training center. Control players continued their "normal practice," which did not include neck-specific strengthening exercises. The 3-times weekly trainer-led intervention program involved a series of 15-second self-resisted contractions, where players pushed maximally against their own head, in forward, backward, left, and right directions. OUTCOME MEASURE: Peak isometric neck strength (force N) into neck flexion, extension, and left and right side flexion was measured using a handheld dynamometer. RESULTS: Postintervention between-group mean differences (MDs) in isometric neck strength change were adjusted for baseline strength and favored the intervention for total neck strength (effect size [ES] = 1.2, MD ± 95% CI = 155.9 ± 101.9 N, P = 0.004) and for neck strength into extension (ES = 1.0, MD ± 95% CI = 59.9 ± 45.4 N, P = 0.01), left side flexion (ES = 0.7, MD ± 95% CI = 27.5 ± 26.9 N, P = 0.05), and right side flexion (ES = 1.3, MD ± 95% CI = 50.5 ± 34.4 N, P = 0.006). CONCLUSION: This resource-efficient neck-strengthening program has few barriers to implementation and provides a clear benefit in U18 players' neck strength. While the present study focused on adolescent rugby players, the program may be appropriate across all sports where head and neck injuries are of concern and resources are limited. CLINICAL RELEVANCE: Greater neck strength is associated with fewer head and neck injuries, including concussion. Performing this neck exercise program independently, or as part of a whole-body program like Activate, an interactive guide for players and coaches, could contribute to lower sports-related head and neck injuries.


Assuntos
Futebol Americano , Lesões do Pescoço , Treinamento Resistido , Adolescente , Futebol Americano/lesões , Humanos , Masculino , Lesões do Pescoço/prevenção & controle , Projetos Piloto , Rugby
15.
Sports Biomech ; : 1-14, 2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34309483

RESUMO

Combining biomechanics and motor control, the aim of this study was to investigate the limit cycle dynamics during the high bar longswing across the UK elite gymnastics pathway age groupings. Senior, junior and development gymnasts (N = 30) performed three sets of eight consecutive longswings on the high bar. The centre of mass motion was examined through Poincaré plots and recurrence quantification analysis exploring the limit cycle dynamics of the longswing. Close to one-dimensional limit cycles were displayed for the senior (correlation dimension (CD) = 1.17 ± .08), junior (CD = 1.26 ± .08) and development gymnasts (CD = 1.33 ± .14). Senior elite gymnasts displayed increased recurrence characteristics in addition to longer longswing duration (p < .01) and lower radial angular velocity of the mass centre (p < .01). All groups of gymnasts had highly recurrent and predictable limit cycle characteristics. The findings of this research support the postulation that the further practice, experience and individual development associated with the senior gymnasts contribute to the refinement of the longswing from a nonlinear dynamics perspective. These findings support the idea of functional task decomposition informing the understanding of skill and influencing coaches' decisions around skill development and physical preparation.

16.
J Sports Sci ; 39(23): 2698-2705, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34278943

RESUMO

This paper is Part II of a study of the effects of practice on young adult novice gymnasts learning the movement coordination pattern of the longswing. The focus was the early stage of learning a critical component of the longswing, namely: through joint motion to inject mechanical energy into the upswing segment effectively to complete the longswing circle. Twenty-five novice male gymnasts received expert instruction while practicing two sessions a week for 3 weeks between a pre- and a post-practice assessment test trial. Seven novices completed a full circle by the end of Test 4. Completion of the longswing was positively related to the angular velocity generated in the gravity driven free fall of the initial segment and the greater rate of energy input in the upward segment. A successful performance in terms of the emergent movement pattern requires coordination of the onset, rate and level of energy input to counterbalance the negative influence of gravity on the second half upwards segment. The development of the complete longswing through the emergence of the collective variable dynamics (Paper 1) and biomechanical energetics of the gymnast (Paper 2) informs coaches, scientists and clinicians regarding task decomposition and learning the longswing.


Assuntos
Ginástica , Aprendizagem , Fenômenos Biomecânicos , Humanos , Masculino , Movimento , Educação Física e Treinamento
17.
J Sports Sci ; 39(23): 2683-2697, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34308780

RESUMO

We studied novice gymnasts (N = 25) learning to form the longswing movement coordination pattern. The focus was the emerging behavioural organisation of centre of mass (CM) dynamics and the relative phase of the bar-CM angular motion. Seven novices learned a complete longswing by the end of the study, 8 novices showed no improvement in proportion of circle completed, and the remainder produced modest but persistent increments of final swing height without achieving a full circle. The radial angular velocity generated in the free fall phase and the circle location of bar-CM relative phase progressively and predominantly predicted circle completion. Bar-CM relative phase produced a consistent qualitative relation within- and between-subjects characteristic of a collective variable with the bar leading the CM on the initial downward antiphase segment and the CM leading on the upward antiphase segment. The ratio of these phases was related by the last practice session to degree of circle completion. The findings showed strong individual differences in the effect of practice on the early steps of learning the movement coordination where the progressive emergence of the longswing circle is driven by exploiting the positive- and minimising the negative-influence of gravity on the bar-CM coordination dynamics (candidate collective variable).


Assuntos
Ginástica , Aprendizagem , Fenômenos Biomecânicos , Humanos , Movimento
18.
J Sports Sci ; 39(19): 2172-2179, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34000964

RESUMO

Biofeedback (BFb) is a useful tool to accelerate the skill development process. Limited research has applied BFb to the whole lower-limb in a complex skill therefore the aim of this research was to assess the effectiveness of a biofeedback intervention targeting whole lower limb kinematics. Thirty-two healthy participants were randomized to a BFb (n = 16) and a Control group (n = 16). Participants visited a motion capture laboratory on three occasions during one week, and returned for retention testing at 4-6 weeks. Following introduction to a novel lunge-touch task, visual BFb on lower limb joint kinematic extension angular velocities (ω) and timing were provided following each lunge. BFb was effective in increasing Hipω (F = 3.746, p = 0.03) and Kneeω (F = 10.241, p = 0.01). Peak Ankleω remained unchanged (F = 1.537, p = 0.23, η2 = 0.05), however Peak Ankleθ (F = 10.915, p < 0.001, η2 = 0.27) and AnkleROM (F = 9.543, p < 0.001, η2 = 0.24) significantly increased. Despite kinematic changes, there were no significant changes in any external kinetics. No significant correlations were found between Hipω, Kneeω or Ankleω and horizontal impulse (ImpulseY: r = 0.20, p = 0.26; r = -0.11, p = 0.24; and r = 0.22, p = 0.28, respectively). Findings demonstrate that BFb can be used to alter multiple kinematic variables in a complex skill, but do not necessarily alter associated kinetic variables not directly targeted by BFb.


Assuntos
Biorretroalimentação Psicológica/métodos , Extremidade Inferior/fisiologia , Movimento/fisiologia , Adulto , Fenômenos Biomecânicos , Feminino , Voluntários Saudáveis , Humanos , Cinética , Masculino , Análise e Desempenho de Tarefas , Adulto Jovem
19.
Sports Biomech ; : 1-15, 2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33660580

RESUMO

Aims of this study were to investigate if changes in elbow and wrist joints loading and biomechanical characteristics of performance existed as a function of (a) different hand placement and (b) fundamental skills development in female gymnastics. Ten female gymnasts performed 54 successful trials of round-off skills (cartwheel [18], round-off [18], round-off to back handspring [18]), with three different hand positions (parallel, T-shape and reverse). Kinematic and kinetic data were collected for each trial. A two-way repeated measures ANOVA was used to analyse the injury risk factors. Findings of the current study showed that an increase in RO skill difficulty level significantly influences the mechanical load on the upper extremities. With the increase in mechanical load on the upper extremities during the reverse and parallel hand positions, this study suggests that that T-shape hand position should be used as the primary technique for the young female. Differences in vertical velocity from touchdown to take-off between the three hand positions for the RO and RO-BH suggested that the reverse position was less effective for young female gymnasts. The findings of the current study demonstrated no clear performance benefits between hand position selection.

20.
Sci Rep ; 11(1): 405, 2021 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-33432011

RESUMO

The aim of this study was to identify motor control solutions associated with the ability to maintain handstand balance. Using a novel approach, we investigated the dynamical interactions between centre of pressure (CoP) and centre of mass (CoM) motion. A gymnastics cohort was divided into a 'less skilled' group, who held handstands for 4-6 s, and a 'more skilled' group, who held handstands in excess of 10 s. CoP-CoM causality was investigated in anterior-posterior (AP) and medio-lateral (ML) directions, in addition to time-space, time-frequency and Hurst Exponent (H) analyses. Lower AP CoP to CoM causal drive and lower H values (> 0.6) indicated the more skilled gymnasts were less reliant on CoP mechanics to drive CoM motion. More skilled performance demonstrated greater adaptability through use of reactive, as opposed to anticipatory, control strategies. Skilled performers additionally exploited mechanical advantages in ML (e.g. a wider base of support), compared to the less skilled athletes. A multiple regression analysis revealed H and frequency domain measures to be better predictors of handstand balance duration than time-space domain measures. The study findings highlight the advantage of an adaptable motor control system with a directional profile, and provide new insight into the clear, measurable footprint of CoP on the dynamics of CoM.


Assuntos
Ginástica/fisiologia , Mãos/fisiologia , Equilíbrio Postural/fisiologia , Postura/fisiologia , Atletas , Fenômenos Biomecânicos , Criança , Feminino , Humanos , Destreza Motora/fisiologia , Dinâmica não Linear , Pressão
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