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1.
J Sports Sci ; 39(8): 887-899, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33241966

RESUMO

In March 2020, the spreading Coronavirus (COVID-19) prompted the United Kingdom government to introduce a societal shutdown, accompanied by self-isolation and social-distancing measures to reduce virus transmission. In doing so, opportunities for physical activity were likely reduced, potentially causing detrimental effects to older adults. Therefore, the present study investigated the influence of the initial six weeks of lockdown on physical activity levels, perceived physical function and mood in older adults. A cross-sectional, mixed-methods, observational study was conducted using self-administered, fortnightly online surveys throughout the UK between 21st March-4 May 2020. A total of 117 participants (52 males [age: 76 ± 4 years] and 65 females [age: 76 ± 4 years]) completed all surveys. Despite lockdown restrictions, this group of older adults maintained their pre-lockdown physical activity levels, but also increased their self-reported sedentary time. Subsequently, perception of physical function was maintained across lockdown. With regards to mood; the only strong evidence for an increase in depression was for males (ps = 95.35%; >0.3 AU), although self-reported levels of depression were similar between sexes at week six. Given the link between sedentary behaviour and negative health outcomes in older adults, strategies to reduce sedentariness during the COVID-19 pandemic are required.


Assuntos
Afeto , COVID-19/psicologia , Exercício Físico , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Masculino , Pandemias , Comportamento Sedentário , Inquéritos e Questionários , Reino Unido
2.
J Sports Sci ; 38(7): 787-794, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32131691

RESUMO

This study identified key somatic and demographic characteristics that benefit all swimmers and, at the same time, identified further characteristics that benefit only specific swimming strokes. Three hundred sixty-three competitive-level swimmers (male [n = 202]; female [n = 161]) participated in the study. We adopted a multiplicative, allometric regression model to identify the key characteristics associated with 100 m swimming speeds (controlling for age). The model was refined using backward elimination. Characteristics that benefited some but not all strokes were identified by introducing stroke-by-predictor variable interactions. The regression analysis revealed 7 "common" characteristics that benefited all swimmers suggesting that all swimmers benefit from having less body fat, broad shoulders and hips, a greater arm span (but shorter lower arms) and greater forearm girths with smaller relaxed arm girths. The 4 stroke-specific characteristics reveal that backstroke swimmers benefit from longer backs, a finding that can be likened to boats with longer hulls also travel faster through the water. Other stroke-by-predictor variable interactions (taken together) identified that butterfly swimmers are characterized by greater muscularity in the lower legs. These results highlight the importance of considering somatic and demographic characteristics of young swimmers for talent identification purposes (i.e., to ensure that swimmers realize their most appropriate strokes).


Assuntos
Destreza Motora/fisiologia , Natação/fisiologia , Adolescente , Aptidão , Braço/anatomia & histologia , Distribuição da Gordura Corporal , Tamanho Corporal , Criança , Comportamento Competitivo , Feminino , Quadril/anatomia & histologia , Humanos , Perna (Membro)/anatomia & histologia , Masculino , Músculo Esquelético/anatomia & histologia , Ombro/anatomia & histologia , Adulto Jovem
3.
Exp Gerontol ; 165: 111838, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35618184

RESUMO

Coronavirus (COVID-19) and its variants, continue to spread globally more than two years after the discovery of the wild-type virus in Wuhan, China. Following the onset of COVID-19, fluctuating restrictions have likely impacted the daily lives of older adults living in the United Kingdom (UK). Subsequently, the longer term effects of COVID-19 on physical activity levels, perceived physical function and mood of older adults are unclear. Therefore, the present study aimed to follow a group of older adult's living in the UK for one year, to monitor physical activity levels, perceived physical function and mood. A longitudinal, mixed-methods, observational study was conducted using self-administered, online surveys at 3-month intervals between March 2020 and June 2021. A total of 100 participants (46 males [age: 76 ± 5 years] and 54 females [age:74 ± 4 years]) completed all surveys. Bayesian analysis allowed calculation of direct probabilities whilst incorporating our prior knowledge. Throughout this period, older adults maintained or increased their pre-lockdown physical activity levels despite a decrease in intensity of effort of physical activity tasks, whilst sitting time increased at two of the follow-up time-points. Furthermore, perceived physical function decreased (ps = 91.78%;>1.21 AU) and mood undulated in a pattern that reflected the tightening and easing of restrictions. Despite total physical activity being maintained, perceived physical function decreased by a small but clinically meaningful margin.


Assuntos
COVID-19 , Idoso , Idoso de 80 Anos ou mais , Teorema de Bayes , Controle de Doenças Transmissíveis , Exercício Físico , Feminino , Seguimentos , Humanos , Masculino , Pandemias
4.
Int J Sports Physiol Perform ; 17(7): 1054-1060, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35361736

RESUMO

PURPOSE: The purpose of this study was to assess the relationship between typical performance tests among elite and professional cyclists when conducted indoors and outdoors. METHODS: Fourteen male cyclists of either UCI (Union Cycliste Internationale) Continental or UCI World Tour level (mean [SD] age 20.9 [2.8] y, mass 68.13 [7.25] kg) were recruited to participate in 4 test sessions (2 indoors and 2 outdoors) within a 14-day period, consisting of maximum mean power testing for durations of 60, 180, 300, and 840 seconds. RESULTS: Across all maximum mean power test durations, the trimmed mean power was higher outdoors compared with indoor testing (P < .05). Critical power was higher outdoors compared with indoors (+19 W, P = .005), while no difference was observed for the work capacity above critical power. Self-selected cadence was 6 rpm higher indoors versus outdoors for test durations of 60 (P = .038) and 300 seconds (P = .002). CONCLUSIONS: These findings suggest that maximal power testing in indoor and outdoor settings cannot be used interchangeably. Furthermore, there was substantial individual variation in the difference between indoor and outdoor maximum mean powers across all time durations, further highlighting the difficulty of translating results from indoor testing to outdoor on an individual level in elite populations.


Assuntos
Ciclismo , Adulto , Fenômenos Biomecânicos , Meio Ambiente , Humanos , Masculino , Adulto Jovem
5.
Med Sci Sports Exerc ; 54(1): 162-168, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34431826

RESUMO

INTRODUCTION: Handgrip strength (HGS) is an important indicator of health. Because HGS is strongly associated with body size, most investigators normalize HGS for some measure of body size as a more sensitive indicator of strength within a population. We aimed to 1) identify the optimal body size dimension to remove (normalize) HGS for differences in body size among adults and 2) generate norm-referenced centiles for HGS using the identified body size dimension. METHODS: Data were from the National Health and Nutrition Examination Survey, a representative sample of the US noninstitutionalized civilian population. Exclusions resulted in a final sample of 8690 adults 20 yr and older. HGS was measured using handheld dynamometry. Body size dimensions included body mass, height, and waist circumference. The most appropriate dimension(s) associated with HGS is identified using allometry. We fitted centile curves for normalized HGS using the generalized additive model for location, scale, and shape. RESULTS: Findings suggest that neither body mass nor body mass index is appropriate to normalize HGS. Incorporating all three body size dimensions of body mass, height, and waist circumference, or the reduced subsets of body mass and height, or height alone, suggests that the most appropriate normalizing (body size) dimension associated with HGS should be a cross-sectional or surface area measure of an individual's body size (i.e., L2, where L is a linear dimension of body size). Given that height was also identified as the signally best body size dimension associated with HGS, we recommend HGS be normalized by height2 (i.e., HGS/HT2). Centile curves for HGS/HT2 by age group and gender were therefore provided. CONCLUSIONS: Scaling adult HGS by height2 may help normalize strength for population-based research.


Assuntos
Pesos e Medidas Corporais/normas , Força da Mão , Dinamômetro de Força Muscular/normas , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Adulto Jovem
6.
Artigo em Inglês | MEDLINE | ID: mdl-33435414

RESUMO

The present study aims to identify the optimal body-size/shape and maturity characteristics associated with superior fitness test performances having controlled for body-size, sex, and chronological-age differences. The sample consisted of 597 Tunisian children (396 boys and 201 girls) aged 8 to 15 years. Three sprint speeds recorded at 10, 20 and 30 m; two vertical and two horizontal jump tests; a change-of-direction and a handgrip-strength tests, were assessed during physical-education classes. Allometric modelling was used to identify the benefit of being an early or late maturer. Findings showed that being tall and light is the ideal shape to be successful at most physical fitness tests, but the height-to-weight "shape" ratio seems to be test-dependent. Having controlled for body-size/shape, sex, and chronological age, the model identified maturity-offset as an additional predictor. Boys who go earlier/younger through peak-height-velocity (PHV) outperform those who go at a later/older age. However, most of the girls' physical-fitness tests peaked at the age at PHV and decline thereafter. Girls whose age at PHV was near the middle of the age range would appear to have an advantage compared to early or late maturers. These findings have important implications for talent scouts and coaches wishing to recruit children into their sports/athletic clubs.


Assuntos
Força da Mão , Esportes , Adolescente , Idoso , Estatura , Criança , Exercício Físico , Feminino , Humanos , Masculino , Aptidão Física
7.
ERJ Open Res ; 7(3)2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34322548

RESUMO

Identifying vulnerable groups and/or individuals' cardiorespiratory fitness (CRF) is an important challenge for clinicians/researchers alike. To quantify CRF accurately, the assessment of several variables is now standard practice including maximal oxygen uptake (V'CO2 ) and ventilatory efficiency, the latter assessed using the minute ventilation/carbon dioxide production (V'E/V'CO2 ) slope. Recently, reference values (centiles) for V'E/V'CO2 slopes for males and females aged 20 to 80 have been published, using cardiopulmonary exercise testing (CPX) data (treadmill protocol) from the Fitness Registry and the Importance of Exercise National Database (FRIEND Registry). In the current observational study we provide centile curves for the FRIEND Registry V'E/V'CO2 slopes, fitted using the generalised additive model for location, scale and shape (GAMLSS), to provide individuals with a more precise estimate of where their V'E/V'CO2 slopes fall within the population. We also confirm that by adopting allometric models (incorporating a log transformation), the resulting ANCOVAs provided more normal and homoscedastic residuals, with superior goodness-of-fit using the Akaike information criterion (AIC)=14 671 (compared with traditional ANCOVA's AIC=15 008) that confirms allometric models are vastly superior to traditional ANCOVA models. In conclusion, providing sex-by-age centile curves rather than referring to reference tables for ventilatory efficiency (V'E/V'CO2 slopes) will provide more accurate estimates of where an individual's particular V'E/V'CO2 slope falls within the population. Also, by adopting allometric models researchers are more likely to identify real and valid inferences when analysing population/group differences in V'E/V'CO2 slopes.

8.
Eur J Sport Sci ; 21(8): 1083-1091, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32772638

RESUMO

AbstractPurpose: Previous research has captured point estimates for population means of somatic variables associated with swimming speed across strokes, but have not determined if predictors of swimming speed operate the same at the upper tails of the distribution (τ = 0.9) as they do at the median levels (τ = 0.5) and lower levels (τ = 0.1). Method: Three hundred sixty-three competitive-level swimmers (male [n = 202]; female [n = 161]) participated in the study. To identify key somatic variables associated with 100-m swimming across and between strokes controlling for age, we used a Bayesian allometric quantile regression model, refined using Bayes Factors and Leave-one-out cross validation. Results: High probabilities (>99%) were found for arm-span, seated-height and shoulder-breadth being the strongest somatic predictors across strokes. For individual strokes, Bayesian quantile regression demonstrated that the relative importance of predictors differs across quantiles. For swimmers in the 0.9 quartile, shoulder-breadth is a more important than height for front-crawl, wide shoulders are important for breaststroke swimmers but can be detrimental when combined with narrow hips, seated-height and hip-width are important for backstroke swimming speed, and calf girth for butterfly. Conclusion: These results highlight the importance of considering key somatic variables for talent identification in swimming and ensure young swimmers focus on strokes compatible with their somatic structure. The most important new insight is that predictors differ for the best swimmers compared to average or poorer swimmers. This has implications beyond swimming, pointing to the importance of considering the upper tails of distributions in performance and talent identification contexts.


Assuntos
Aptidão , Desempenho Atlético/fisiologia , Somatotipos , Natação/fisiologia , Adolescente , Braço/anatomia & histologia , Teorema de Bayes , Criança , Comportamento Competitivo/fisiologia , Feminino , Quadril/anatomia & histologia , Humanos , Perna (Membro)/anatomia & histologia , Masculino , Ombro/anatomia & histologia
9.
Int J Sports Physiol Perform ; 16(2): 199-207, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-32994386

RESUMO

PURPOSE: To investigate the influence of recruitment age on retention and release across the development pathway and to explore the influence of anthropometric and physical characteristics on retention and release at different ages throughout the development pathway and the likelihood of obtaining a professional contract. METHODS: Following receipt of ethics approval, a cross-sectional study tracking 4 cohorts of players over 5 years assessed 76 male youth football players (11-16 y) from an English football academy on 3 occasions annually in anthropometry, countermovement jump height, and linear (30 and 15 m) and multidirectional sprint time. Players were categorized based on their start and release date. RESULTS: Starting early (ie, before U12) in an academy was a key indicator of obtaining a professional contract, representing 87% of the players signed. Bayesian regression models suggest that the majority of differences in physical characteristics between players that were released and retained are trivial, small, and/or uncertain. Players who attained a professional contract at 18 had slower 15- and 30-m sprint times at U13 to U15 (P > 0 = .87-.99), slower multidirectional sprint times at U14 (P > 0 = .99), and lower countermovement jump height at U13 to U16 (P > 0 = .88-.99) compared with players who did not gain a contract. CONCLUSION: Players recruited early have an increased likelihood of gaining a professional contract. Physical assessments lack utility when used in isolation as a talent-identification tool.


Assuntos
Fatores Etários , Antropometria , Aptidão Física , Futebol , Adolescente , Desempenho Atlético , Teorema de Bayes , Criança , Estudos Transversais , Humanos , Masculino
10.
Children (Basel) ; 5(10)2018 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-30257491

RESUMO

Despite the known benefits of engaging in daily moderate to vigorous physical activity (MVPA), only 22% of children in England are meeting the recommended guidelines. School break times have been advocated as a key part of children's daily routines in which their MVPA can be increased. The main aim of this study was to evaluate the effect of installing a walking-track on children's MVPA during school break times. A mixed method design was employed which allowed for the quantitative measurement of children's PA at three time points (baseline, mid-intervention (1⁻5 weeks) and follow-up (6⁻9 weeks)), using pedometers (n = 81, 5⁻9 years) and systematic observation (n = 23, 7⁻9 years). A semi-structured interview (n = 1) was also conducted at 10 weeks' follow-up. The installation of the walking-track was grounded in a unique set of theoretical constructs to aid the behaviour change of the teachers. Short term positive increases in girls' and boys' MVPA and longer term increases in boys' vigorous PA (VPA) were found. Qualitative data highlighted that boys dominated the walking-track and the inconsistent behaviour of school staff negatively impacted upon children's MVPA. A set of principles to guide the installment of walking-tracks in school playgrounds are recommended.

11.
Front Psychol ; 8: 1270, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28824479

RESUMO

Mental toughness (MT) is a key psychological variable related to perseverance and success in performance domains. MT and its development has been explored across a range of contexts and across different sports, but no research to date has examined MT in relation to Paralympic athletes. We sought to understand the lived-experiences of mentally tough Paralympians, aiming to conceptualize MT in a Paralympic context and investigate its development. Ten Paralympic athletes were interviewed using in-depth, semi-structured interviews. The verbatim transcripts of the interviews served as the data for an interpretative phenomenological analysis. Three broad themes and several subthemes emerged in conceptualizing Paralympian MT: characteristics (determination, defiance, pragmatic, optimistic, resilient, self-belief and independence and autonomy), cognitions (normalization, sense of escape, non-acceptance of constraints, influence perception and connection) and cognitive strategies (rational thinking, goal setting, pain management and control). In understanding MT development, two broad themes and several subthemes emerged: formative experiences (challenge, classification, setbacks, critical incident, trauma and recovery, sustained commitment, development of mind-set and perspective during challenge, failure, and acceptance), and support and coping resources (social support and significant others, external shaping, social support, overcoming problems, social comparison and reflective practice). The findings suggest that Paralympians benefited from exposure to highly demanding situations in a supportive environment and this helped develop mentally tough characteristics and behaviors and individualized cognitive coping strategies. Our findings highlight the association between the adaptive development of personal characteristics by overcoming physical and mental setbacks over a sustained time period. Overall, the findings suggest that to develop mentally tough characteristics and behaviors, athletes in general could benefit from exposure to highly demanding situations in a supportive environment.

12.
J Sports Sci Med ; 5(CSSI): 21-7, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-24357972

RESUMO

MuayThai is a combat sport with a growing international profile but limited research conducted into judging practices and processes. Problems with judging of other subjectively judged combat sports have caused controversy at major international tournaments that have resulted in changes to scoring methods. Nationalistic bias has been central to these problems and has been identified across a range of sports. The aim of this study was to examine nationalistic bias in MuayThai. Data were collected from the International Federation of MuayThai Amateur (IFMA) World Championships held in Almaty, Kazakhstan September 2003 and comprised of tournament results from 70 A-class MuayThai bouts each judged by between five and nine judges. Bouts examined featured 62 competitors from 21 countries and 25 judges from 11 countries. Results suggested that nationalistic bias was evident. The bias observed equated to approximately one round difference between opposing judges over the course of a bout (a mean of 1.09 (SE=0.50) points difference between judges with opposing affilations). The number of neutral judges used meant that this level of bias generally did not influence the outcome of bouts. Future research should explore other ingroup biases, such as nearest neighbour bias and political bias as well as investigating the feasibility adopting an electronic scoring system. Key PointsNationalistic bias is evident in international amateur MuayThai judging.The impact on the outcome of bouts is limited.The practice of using a large number of neutral judges appears to reduce the impact of nationalistic bias.

13.
Front Psychol ; 5: 532, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24917839

RESUMO

Different factors have been postulated to explain the home advantage phenomenon in sport. One plausible explanation investigated has been the influence of a partisan home crowd on sports officials' decisions. Different types of studies have tested the crowd influence hypothesis including purposefully designed experiments. However, while experimental studies investigating crowd influences have high levels of internal validity, they suffer from a lack of external validity; decision-making in a laboratory setting bearing little resemblance to decision-making in live sports settings. This focused review initially considers threats to external validity in applied and theoretical experimental research. Discussing how such threats can be addressed using representative design by focusing on a recently published study that arguably provides the first experimental evidence of the impact of live crowd noise on officials in sport. The findings of this controlled experiment conducted in a real tournament setting offer a level of confirmation of the findings of laboratory studies in the area. Finally directions for future research and the future conduct of crowd noise studies are discussed.

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