RESUMO
BACKGROUND: There is evidence that most people are aware of the importance of healthy eating and have a broad understanding regarding types of food that enhance or detract from health. However, greater health literacy does not always result in healthier eating. Andreasen's Social Marketing Model and Community-Based Social Marketing both posit that, in order to change health behaviours, it is crucial to understand reasons for current behaviours and perceived barriers and benefits to improved behaviours. Limited research has been conducted, however, that explores these issues with general populations. This study aimed to help address this gap in the evidence using a qualitative methodology. METHODS: Three group discussions were conducted with a total of 23 participants: (1) young women aged 18-24 with no children; (2) women aged 35-45 with primary school aged children; and (3) men aged 35-50 living with a partner and with pre- or primary school aged children. The discussions took place in a regional centre of Victoria, Australia. Transcriptions were thematically analysed using an inductive descriptive approach and with reference to a recent integrated framework of food choice that identified five key interrelated determinants: food- internal factors; food- external factors; personal-state factors; cognitive factors; and sociocultural factors. RESULTS: We found that food choice was complex, with all five determinants evident from the discussions. However, the "Social environment" sub-category of "Food-external factors", which included family, work, and social structures, and expectations (or perceived expectations) of family members, colleagues, friends, and others, was particularly prominent. Knowledge that one should practice healthy eating, which falls under the "Cognitive factor" category, while seen as an aspiration by most participants, was often viewed as unrealistic, trumped by the need and/or desire for convenience, a combination of Food-external factor: Social environment and Personal-state factor: Psychological components. CONCLUSIONS: We found that decisions regarding what, when, and how much to eat are seen as heavily influenced by factors outside the control of the individual. It appears, therefore, that a key to improving people's eating behaviours is to make it easy to eat more healthfully, or at least not much harder than eating poorly.
Assuntos
População Australasiana , Pesquisa Qualitativa , População Rural , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Dieta Saudável/psicologia , Comportamento Alimentar/psicologia , Grupos Focais , Preferências Alimentares/psicologia , População Rural/estatística & dados numéricos , Vitória , CriançaRESUMO
Both sleep loss and exercise regulate gene expression in skeletal muscle, yet little is known about how the interaction of these stressors affects the transcriptome. The aim of this study was to investigate the effect of nine nights of sleep restriction (SR), with repeated resistance exercise (REx) sessions, on the skeletal muscle transcriptome of young, trained females. Ten healthy females aged 18-35 yr old undertook a randomized cross-over study of nine nights of SR (5 h time in bed) and normal sleep (NS; ≥7 h time in bed) with a minimum 6-wk washout. Participants completed four REx sessions per condition (days 3, 5, 7, and 9). Muscle biopsies were collected both pre- and post-REx on days 3 and 9. Gene and protein expression were assessed by RNA sequencing and Western blot, respectively. Three or nine nights of SR had no effect on the muscle transcriptome independently of exercise. However, close to 3,000 transcripts were differentially regulated (false discovery rate < 0.05) 48 h after the completion of three resistance exercise sessions in both NS and SR conditions. Only 39% of downregulated genes and 18% of upregulated genes were common between both conditions, indicating a moderating effect of SR on the response to exercise. SR and REx interacted to alter the enrichment of skeletal muscle transcriptomic pathways in young, resistance-trained females. Performing exercise when sleep restricted may not provide the same adaptive response for individuals as if they were fully rested.NEW & NOTEWORTHY This study investigated the effect of nine nights of sleep restriction, with repeated resistance exercise sessions, on the skeletal muscle transcriptome of young, trained females. Sleep restriction and resistance exercise interacted to alter the enrichment of skeletal muscle transcriptomic pathways in young, resistance-trained females. Performing exercise when sleep restricted may not provide the same adaptive response for individuals as if they were fully rested.
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Estudos Cross-Over , Músculo Esquelético , Treinamento Resistido , Privação do Sono , Transcriptoma , Humanos , Feminino , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiologia , Treinamento Resistido/métodos , Adulto Jovem , Adulto , Transcriptoma/genética , Adolescente , Privação do Sono/genética , Exercício Físico/fisiologia , Regulação da Expressão Gênica , Perfilação da Expressão Gênica/métodosRESUMO
PURPOSE: Uncertainty exists if post-resistance exercise hydrotherapy attenuates chronic inflammatory and hormone responses. The effects of repeated post-resistance exercise water immersion on inflammatory and hormone responses in athletes were investigated. METHODS: Male, academy Super Rugby players (n = 18, 19.9 ± 1.5 y, 1.85 ± 0.06 m, 98.3 ± 10.7 kg) participated in a 12-week programme divided into 3 × 4-week blocks of post-resistance exercise water immersion (either, no immersion control [CON]; cold [CWI]; or hot [HWI] water immersion), utilising a randomised cross-over pre-post design. Fasted, morning blood measures were collected prior to commencement of first intervention block, and every fourth week thereafter. Linear mixed-effects models were used to analyse main (treatment, time) and interaction effects. RESULTS: Repeated CWI (p = 0.025, g = 0.05) and HWI (p < 0.001, g = 0.62) reduced creatine kinase (CK), compared to CON. HWI decreased (p = 0.013, g = 0.59) interleukin (IL)-1ra, compared to CON. HWI increased (p < 0.001-0.026, g = 0.06-0.17) growth factors (PDGF-BB, IGF-1), compared to CON and CWI. CWI increased (p = 0.004, g = 0.46) heat shock protein-72 (HSP-72), compared to HWI. CONCLUSION: Post-resistance exercise CWI or HWI resulted in trivial and moderate reductions in CK, respectively, which may be partly due to hydrostatic effects of water immersion. Post-resistance exercise HWI moderately decreased IL-1ra, which may be associated with post-resistance exercise skeletal muscle inflammation influencing chronic resistance exercise adaptive responses. Following post-resistance exercise water immersion, CWI increased HSP-72 suggesting a thermoregulatory response indicating improved adaptive inflammatory responses to temperature changes, while HWI increased growth factors (PDGF-BB, IGF-1) indicating different systematic signalling pathway activation. Our data supports the continued use of post-resistance exercise water immersion recovery strategies of any temperature during in-season competition phases for improved inflammatory adaptive responses in athletes.
Assuntos
Estudos Cross-Over , Imersão , Inflamação , Treinamento Resistido , Humanos , Masculino , Treinamento Resistido/métodos , Adulto Jovem , Futebol Americano/fisiologia , Temperatura Alta , Hidroterapia/métodos , Temperatura Baixa , Atletas , Fator de Crescimento Insulin-Like I/metabolismoRESUMO
This systematic review investigates influences of mobility training in sporting populations on performance outcomes. The search strategy involved Embase, MEDLINE Complete, Sports Discus and manual search from inception to March 2022. Mobility training studies with a minimum three-week, or 10-session duration in healthy sporting populations of any age were included. Twenty-two studies comprising predominantly young adult or junior athletes were analysed from 319 retrieved articles. Performance outcomes were strength, speed, change of direction, jumping, balance, and sport-specific skills. Fifteen studies randomized participants with only four indicating systematic allocation concealment and blinding of outcomes assessors in only one study. In 20 of 22 studies mobility training was of some benefit or helped to maintain sports performance to a larger degree than control conditions. Control conditions, which were generally no activity conditions, were primarily non-significant. The majority of evidence suggests that a range of mobility training methods may improve key sports performance variables or are unlikely to impair performance over time. Therefore, coaches can consider the potential benefits of including comprehensive mobility programmes with minimal risk of impairing performance. Higher-quality studies in homogenous populations are necessary to confirm performance changes.
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Desempenho Atlético , Condicionamento Físico Humano , Humanos , Desempenho Atlético/fisiologia , Condicionamento Físico Humano/métodos , Condicionamento Físico Humano/fisiologia , Força Muscular/fisiologia , Adaptação Fisiológica , Equilíbrio Postural/fisiologia , Destreza Motora/fisiologiaRESUMO
Evidence supports that intuitive eating is associated with many indicators of positive physical and mental health, with more recent longitudinal studies establishing causality. Most research, however, comprises either survey data or clinical trials. This study attempts to fill this evidentiary gap by using a qualitative methodology to explore people's understandings and reactions to intuitive eating, including perceived barriers and enablers to implementation. Three focus group discussions were conducted in a non-metropolitan region of Victoria, Australia, with a total of 23 participants. Focus group transcripts were thematically analysed using an inductive descriptive approach within a constructionist perspective. Findings indicate that the concept of intuitive eating was either unknown or misunderstood. Once intuitive eating was explained, most responses to implementing intuitive eating were negative. Participants felt that having complete choice around what they ate was unlikely to equate to a healthy or balanced diet, at least in the short term. They also argued that because everyday life was not intuitive in its structures, it would be difficult to eat intuitively. Despite these difficulties, participants appreciated that if they were able to overcome the various barriers and achieve a state of intuitive eating, they anticipated a range of long-term benefits to health and weight management. For intuitive eating to become a viable public health approach, this research suggests that intuitive eating needs to be much more widely publicised and better explained, and perhaps renamed. More significantly, people would need assistance with how to eat intuitively given the barriers identified.
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Comportamento Alimentar , Nível de Saúde , Intuição , Humanos , Emoções , Grupos Focais , Vitória , Comportamento Alimentar/psicologia , Pesquisa QualitativaRESUMO
ABSTRACT: Horgan, BG, Tee, N, West, NP, Drinkwater, EJ, Halson, SL, Colomer, CME, Fonda, CJ, Tatham, J, Chapman, DW, and Haff, GG. Acute performance, daily well-being and hormone responses to water immersion after resistance exercise in junior international and subelite male volleyball athletes. J Strength Cond Res 37(8): 1643-1653, 2023-Athletes use postexercise hydrotherapy strategies to improve recovery and competition performance and to enhance adaptative responses to training. Using a randomized cross-over design, the acute effects of 3 postresistance exercise water immersion strategies on perceived recovery, neuromuscular performance, and hormone concentrations in junior international and subelite male volleyball athletes ( n = 18) were investigated. After resistance exercise, subjects randomly completed either 15-minute passive control (CON), contrast water therapy (CWT), cold (CWI), or hot water immersion (HWI) interventions. A treatment effect occurred after HWI; reducing perceptions of fatigue (HWI > CWT: p = 0.05, g = 0.43); improved sleep quality, compared with CON ( p < 0.001, g = 1.15), CWI ( p = 0.017, g = 0.70), and CWT ( p = 0.018, g = 0.51); as well as increasing testosterone concentration (HWI > CWT: p = 0.038, g = 0.24). There were trivial to small ( p < 0.001-0.039, g = 0.02-0.34) improvements (treatment effect) in jump performance (i.e., squat jump and countermovement jump) after all water immersion strategies, as compared with CON, with high variability in the individual responses. There were no significant differences (interaction effect, p > 0.05) observed between the water immersion intervention strategies and CON in performance ( p = 0.153-0.99), hormone ( p = 0.207-0.938), nor perceptual ( p = 0.368-0.955) measures. To optimize recovery and performance responses, e.g., during an in-season competition phase, postresistance exercise HWI may assist with providing small-to-large improvements for up to 38 hours in perceived recovery (i.e., increased sleep quality and reduced fatigue) and increases in circulating testosterone concentration. Practitioners should consider individual athlete neuromuscular performance responses when prescribing postexercise hydrotherapy. These findings apply to athletes who aim to improve their recovery status, where postresistance exercise HWI optimizes sleep quality and next-day perceptions of fatigue.
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Treinamento Resistido , Voleibol , Humanos , Masculino , Água , Imersão , Atletas , Fadiga , Testosterona , Temperatura BaixaRESUMO
PURPOSE: Following resistance exercise, uncertainty exists as to whether the regular application of cold water immersion attenuates lean muscle mass increases in athletes. The effects of repeated post-resistance exercise cold versus hot water immersion on body composition and neuromuscular jump performance responses in athletes were investigated. METHODS: Male, academy Super Rugby players (n = 18, 19.9 ± 1.5 y, 1.85 ± 0.06 m, 98.3 ± 10.7 kg) participated in a 12-week (4-week × 3-intervention, i.e., control [CON], cold [CWI] or hot [HWI] water immersion) resistance exercise programme, utilising a randomised cross-over pre-post-design. Body composition measures were collected using dual-energy X-ray absorptiometry prior to commencement and every fourth week thereafter. Neuromuscular squat (SJ) and counter-movement jump (CMJ) performance were measured weekly. Linear mixed-effects models were used to analyse main (treatment, time) and interaction effects. RESULTS: There were no changes in lean (p = 0.960) nor fat mass (p = 0.801) between interventions. CON (p = 0.004) and CWI (p = 0.003) increased (g = 0.08-0.19) SJ height, compared to HWI. There were no changes in CMJ height (p = 0.482) between interventions. CONCLUSION: Repeated post-resistance exercise whole-body CWI or HWI does not attenuate (nor promote) increases in lean muscle mass in athletes. Post-resistance exercise CON or CWI results in trivial increases in SJ height, compared to HWI. During an in-season competition phase, our data support the continued use of post-resistance exercise whole-body CWI by athletes as a recovery strategy which does not attenuate body composition increases in lean muscle mass, while promoting trivial increases in neuromuscular concentric-only squat jump performance.
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Treinamento Resistido , Humanos , Masculino , Rugby , Estudos Cross-Over , Imersão , Estações do Ano , Água , Composição Corporal , Temperatura BaixaRESUMO
PURPOSE: To determine whether the most important physical qualities in elite Australian male and female cricket pace bowlers change with age and phase of the cricket season. METHODS: An existing longitudinal database (7 cricket seasons) of selected and routinely collected physical testing data from 103 male and 58 female elite Australian pace bowlers age 18-30 years was retrospectively analyzed. Male and female physical testing data from the isometric midthigh pull, 1-repetition-maximum bench pull, run-of-3, and countermovement jump (male only) were analyzed separately by performing linear mixed models on each of the physical qualities. Type III analysis-of-variance tests were conducted to determine if a significant effect existed within the fixed effects of age, season phase, and the age × season phase interaction. Appropriate pairwise comparisons were conducted. RESULTS: Absolute and relative measures of force in the isometric midthigh pull and strength in the 1-repetition-maximum bench pull tests were significantly greater in older male and female pace bowlers. Older male pace bowlers demonstrated significantly faster absolute and relative best run-of-3 times. CONCLUSIONS: Most physical qualities across both male and female pace bowlers demonstrated an improvement with age. This is likely due to a training effect and would be anticipated to lead to a gradual enhancement of ball release speed, in accordance with previous research. Future research should look to investigate the relationship between the development of physical qualities and ball release speed among elite male and female pace bowlers.
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Esportes , Humanos , Feminino , Masculino , Idoso , Adolescente , Adulto Jovem , Adulto , Estudos Retrospectivos , Austrália , Fenômenos BiomecânicosRESUMO
INTRODUCTION: Female athletes sleep less and report more sleep problems than their male counterparts. Inadequate sleep reduces maximal strength in male athletes; however, little is known about the impact of sleep restriction (SR) on the quantity and quality of resistance exercise performed by female athletes. This study investigated the effect of nine nights of moderate SR on repeated resistance exercise performance, hormonal responses, and perceived fatigue in females. METHODS: Ten healthy, resistance-trained, eumenorrheic females age 18-35 yr underwent nine nights of SR (5-h time in bed) and normal sleep (NS; ≥7-h time in bed) in a randomized, crossover fashion with a minimum 6-wk washout. Participants completed four resistance exercise sessions per trial, with blood samples collected before and after exercise. Exercise performance was assessed using volume load, reactive strength index, and mean concentric velocity with rating of perceived exertion recorded after exercise. Participants completed awakening saliva sampling and the Multi-component Training Distress Scale daily. RESULTS: Volume load decreased trivially (<1%, P < 0.05) with SR. Mean concentric velocity per set was slower during SR for the lower-body (up to 15%, P < 0.05), but not the upper-body, compound lifts. Intraset velocity loss was up to 7% greater during SR for back squats ( P < 0.05). SR increased salivary cortisol area under the curve (by 42%), total training distress (by 84%), and session perceived exertion (by 11%). CONCLUSIONS: Sustained SR reduces markers of resistance exercise quality (bar velocity) more than quantity (volume load) and increases perceived effort at the same relative intensity in resistance-trained females. Markers of exercise quality and internal load may be more sensitive than volume load, to advise coaches to the decline in lifting performance for female athletes experiencing SR.
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Treinamento Resistido , Adolescente , Adulto , Feminino , Humanos , Adulto Jovem , Atletas , Exercício Físico/fisiologia , Sono/fisiologia , Privação do SonoRESUMO
BACKGROUND: Many studies rely on self-reported height and weight. While a substantial body of literature exists on misreporting of height and weight, little exists on improving accuracy. The aim of this study was to determine, using an experimental design and a comparative approach, whether the accuracy of self-reported height and weight data can be increased by improving how these questions are asked in surveys, drawing on the relevant evidence from the psychology and survey research literatures. METHODS: Two surveys from two separate studies were used to test our hypotheses (Science Survey, n = 1,200; Eating Behaviours Survey, n = 200). Participants were randomly assigned to one of six conditions, four of which were designed to improve the accuracy of the self-reported height and weight data ("preamble"), and two of which served as the control conditions ( "no preamble"). Four hypotheses were tested: (H1) survey participants read a preamble prior to being asked their height and weight will report lower heights and higher weights than those not read a preamble; (H2) the impact of question-wording (i.e., preamble vs. no preamble) on self-reported weight will be greater for participants with higher BMIs; (H3) the impact of question-wording on height will be greater for older participants; (H4) either version of the weight question - standard or "weight-specific"-may result in participants reporting more accurate self-reported weight. One-way MANOVA was conducted to test Hypothesis 1; two-way analysis of variance were conducted to test Hypothesis 2; moderation analysis was used to test Hypothesis 3; independent samples t-test was conducted to test Hypothesis 4. RESULTS: None of the hypotheses was supported. CONCLUSIONS: This paper provides an important starting point from which to inform further work exploring how question wording can improve self-reported measurement of height and weight. Future research should explore how question preambles may or may not operationalise hypothesised underlying mechanisms, the sensitivity or intrusiveness of height and weight questions, individual beliefs about one's height and weight, and survey context.
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Estatura , Obesidade , Peso Corporal , Humanos , Autorrelato , Inquéritos e QuestionáriosRESUMO
ABSTRACT: Dudley, CE, Drinkwater, EJ, and Feros, SA. Different cluster-loading protocols have no effect on intraset and interset power expression. J Strength Cond Res 36(7): 1763-1769, 2022-This study investigated the effect of cluster-loading protocols on changes in hang power clean (HPC) power characteristics. Ten trained weightlifters (7 male, 3 female, HPC 1.28 [M]; 1.03 [F] × body mass) completed 4 experimental protocols in a randomized repeated-measures design. Protocols were traditional, a basic cluster, and 2 undulating clusters. Each protocol comprised 3 sets of 5 HPC repetitions at an average of 70% 1 repetition maximum (RM). The load for undulating cluster protocols ranged between 60 and 80% 1RM. Countermovement jumps (CMJs) were performed before and after each protocol to gauge effect on neuromuscular status. Statistical analysis comprised a one-way repeated measures analysis of variance. Peak power was significantly greater in the fifth repetition of the basic cluster set protocol compared with the traditional set protocol (mean ± SD: 6.6 ± 2.8%, p = 0.043, g = 0.25). Neither undulating load protocol significantly altered set power characteristics compared with basic cluster sets; however, when analyzing repetition data, peak power increased as load increased (and vice versa), indicating the prescribed loads were suboptimal for power expression in this sample. There was no change in CMJ height between protocols. Coaches should prescribe inter-repetition rest to maintain peak power across multiple repetitions and sets. Basic cluster protocols seem to be the most practical choice over undulating cluster protocols because there is no need to adjust load between repetitions.
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Treinamento Resistido , Feminino , Humanos , Masculino , Força Muscular , Músculo Esquelético , Treinamento Resistido/métodos , DescansoRESUMO
PURPOSE: This study investigated the differences between selected physical attributes and ball release speed in slower and faster male and female elite pace bowlers. METHODS: Twelve physical attributes and ball release speed were retrospectively analyzed from 63 male and 31 female elite pace bowlers over the course of 5 seasons. Pace bowlers were categorized as either fast (>122.9 km/h, males and >97.8 km/h, females) or slow (<122.9 km/h, males and <97.8 km/h, females) for each sex. Differences in physical attributes between slower and faster bowling groups were compared using Cohen d effect sizes. RESULTS: Faster pace bowlers displayed differences in isometric midthigh-pull peak force (d = 0.25, males and d = 0.68, females) and relative peak force (d = 0.62, males and d = 0.77, females). Faster male pace bowlers displayed differences in relative (d = 0.61) and absolute (d = 0.39) countermovement jump heights. Faster female pace bowlers displayed differences in 1-repetition-maximum bench-pull strength (d = 0.45) and run-of-3 performance (relative average, d = 1.22; relative best, d = 1.12; average, d = 0.49; and best, d = 0.40). CONCLUSIONS: Anaerobic dominant physical attributes appear to be important in both male and female pace bowlers. The contribution of these physical attributes to ball release speed appears to differ slightly between males and females. Lower-body strength (males and females), lower-body power (males), relative anaerobic capacities (females), and upper-body strength (females) appear to distinguish between slower and faster elite pace bowlers.
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Esportes , Fenômenos Biomecânicos , Feminino , Humanos , Masculino , Estudos RetrospectivosRESUMO
INTRODUCTION: Rural Australians have comparatively higher rates of overweight and obesity, as well as some mental health issues. Intuitive eating has been shown to be positively associated with an array of physical and mental health indicators. Few studies, however, have been conducted with general populations, and none has explicitly examined intuitive eating among rural residents. OBJECTIVE: To investigate the prevalence of intuitive eating, and associations between intuitive eating and indicators of physical and mental health, among a general population of rural adults. DESIGN: Cross-sectional telephone survey of 200 randomly selected, non-metropolitan, English-speaking Australian residents aged 18 or older. FINDINGS: The prevalence of intuitive eating in the sample was 17.6%, with a higher level of intuitive eating among men than women (26.1% vs 9.1%). Bivariate associations between intuitive eating and each of the six health indicators were all positive and mostly statistically significant. Particularly strong was the correlation between intuitive eating and self-esteem for women (r = 0.53). After controlling for indication of an eating disorder and demographics, the associations between intuitive eating and the outcome variables held for body mass index (BMI), psychological distress and body esteem for men, and for BMI and self-esteem for women. Post hoc analyses found that BMI did not moderate the relationship for women between intuitive eating and self-esteem and that body esteem mediates the relationships between intuitive eating and BMI and psychological distress for men, and between intuitive eating and self-esteem for women. DISCUSSION: Consistent with most prior research, this study finds that intuitive eating is positively associated with several indicators of both physical and mental health among non-metropolitan residents in Australia. Practice of intuitive eating in this population, however, is low. These findings may help allied health professionals guide rural populations to better health, and may be a particularly effective approach for people for whom the barriers to seeking out health services are high. CONCLUSION: Intuitive eating appears to have substantial correlations with mental health indicators, and to some extent, physical health indicators, among rural Australians and therefore should be further investigated for its potential to inform public health policy targeted to similar populations.
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Saúde Mental , População Rural , Adulto , Austrália/epidemiologia , Índice de Massa Corporal , Estudos Transversais , Feminino , Humanos , MasculinoRESUMO
OBJECTIVES: The purpose of this study was to document the technical and transferrable skills required for sport scientists, and perceived employment opportunities both currently and in the future with a particular emphasis on comparisons between academic and applied sport scientists. DESIGN: Cross-sectional survey methodology. METHODS: 117 Australian sport science employees completed an online survey capturing demographic information, perceptions about the importance of technical skills, transferable skills, future employment opportunities as well as free-text information on future careers, challenges, and opportunities for the profession. Descriptive statistics were used to summarise information and comparisons made between academic and applied sport science participants. RESULTS: Participants were predominantly male and 35â¯years or younger, with half reporting they held only one position within the industry. Most technical and transferrable skills were rated as important (>4.0 out of 5.0), with practitioner-focused skills rated somewhat more important by applied sport scientists compared to scientific-focused skills rated somewhat more important by academics, and applied sport scientists generally rating transferable skills as more important compared to academics (dâ¯>â¯0.5). Value and supply/demand were identified as challenges to the industry with discipline-specific roles and non-elite populations considered areas for future jobs. CONCLUSIONS: Participants felt there would be more jobs in the future and that these would be in discipline-specific roles and/or non-elite populations. Both technical and interpersonal skills were considered important for sport scientists. The greatest challenges are how sport science is valued and the potential oversupply of sport science graduates.
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Médicos , Esportes , Austrália , Estudos Transversais , Emprego , Feminino , Humanos , MasculinoRESUMO
OBJECTIVE: The aim of the study was to compare training and match loads for cerebral palsy football athletes in a state-level development program to assess the specificity of training for competition in the para sport. DESIGN: Time-motion analysis and heart-rate monitoring were applied during 20 training sessions of the Western Australia CP Football 2017 training season and seven competition matches of the 2017 Australian National Championships. The study used an observational study design with between-subjects and within-subjects comparisons of training and match loads. RESULTS: There were no significant differences between training and match loads in players' measurements of speed components and heart rates, with two exceptions: higher match distance covered in very high speed ( g = 0.33) and time in heart rate zone 1 (<75% heart rate max, g = 0.45) and less time in heart rate zone 2 ( g = 0.42). CONCLUSIONS: Our results indicate that the athletes were conditioned to perform at similar intensities implemented during training, as demonstrated by the consistency between competition and training data in total distance, relative speed zones, and relative heart rate zones. Coaches should apply this knowledge in the programming of training volume and intensities to obtain peak match fitness and specifically prepare athletes for competition in cerebral palsy football.
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Desempenho Atlético , Paralisia Cerebral , Futebol Americano , Masculino , Humanos , Sistemas de Informação Geográfica , Desempenho Atlético/fisiologia , Austrália , Futebol Americano/fisiologiaRESUMO
ABSTRACT: Horgan, BG, West, NP, Tee, N, Drinkwater, EJ, Halson, SL, Vider, J, Fonda, CJ, Haff, GG, and Chapman, DW. Acute inflammatory, anthropometric, and perceptual (muscle soreness) effects of postresistance exercise water immersion in junior international and subelite male volleyball athletes. J Strength Cond Res 36(12): 3473-3484, 2022-Athletes use water immersion strategies to recover from training and competition. This study investigated the acute effects of postexercise water immersion after resistance exercise. Eighteen elite and subelite male volleyball athletes participated in an intervention using a randomized cross-over design. On separate occasions after resistance exercise, subjects completed 1 of 4 15-minute interventions: control (CON), cold water immersion (CWI), contrast water therapy (CWT), or hot water immersion (HWI). Significance was accepted at p ≤ 0.05. Resistance exercise induced significant temporal changes (time effect) for inflammatory, anthropometric, perceptual, and performance measures. Serum creatine kinase was reduced ( g = 0.02-0.30) after CWI ( p = 0.007), CWT ( p = 0.006), or HWI ( p < 0.001) vs. CON, whereas it increased significantly ( g = 0.50) after CWI vs. HWI. Contrast water therapy resulted in significantly higher ( g = 0.56) interleukin-6 concentrations vs. HWI. Thigh girth increased ( g = 0.06-0.16) after CWI vs. CON ( p = 0.013) and HWI ( p < 0.001) and between CWT vs. HWI ( p = 0.050). Similarly, calf girth increased ( g = 0.01-0.12) after CWI vs. CON ( p = 0.039) and CWT ( p = 0.018), and HWI vs. CON ( p = 0.041) and CWT ( p = 0.018). Subject belief in a postexercise intervention strategy was associated with HSP72 ("believer">"nonbeliever," p = 0.026), muscle soreness ("believer">"nonbeliever," p = 0.002), and interleukin-4 ("nonbeliever">"believer," p = 0.002). There were no significant treatment × time (interaction effect) pairwise comparisons. Choice of postexercise water immersion strategy (i.e., cold, contrast, or hot) combined with a belief in the efficacy of that strategy to enhance recovery or performance improves biological and perceptual markers of muscle damage and soreness. On same or subsequent days where resistance exercise bouts are performed, practitioners should consider athlete beliefs when prescribing postexercise water immersion, to reduce muscle soreness.
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Mialgia , Voleibol , Masculino , Humanos , Mialgia/prevenção & controle , Água , Imersão , Atletas , Temperatura Baixa , Músculo Esquelético/fisiologiaRESUMO
he underlying biomechanical benefits of hook-grip (HG) over conventional closed-grip (CG) remain unclear. This study compared bar-path kinematics and force-time variables of the power clean (PC) performed with HG or CG. We also aimed to compared kinetic changes measured by force platform versus linear position transducer (LPT). Eleven well-trained men volunteered. Following a familiarisation session, HG, and CG 1RM conditions, were randomly completed seven days apart. System kinetics and barbell kinematics were recorded via synchronized force platform+LPT system and two-dimensional motion-capture. Statistical parametric mapping (SPM), analysis of variance, and standardised differences were utilised. The SPM cut-offs were determined via novel combination of force and displacement. No between-condition differences in normalised force-time variables of the pull or catch were detected. The first and second pull duration was similar between conditions (ES = 0.04-0.38). Conversely, catch and total PC durations were shorter at 80-95% (ES = 0.26-0.75), with the weightless phase more prolonged at 95% and 100% (ES = 0.54-0.76) with HG compared to CG. Improved timing of the turnover and catch phases appears to be the primary difference between HG and CG performance. Thus, grip type is possibly irrelevant to non-weightlifting athletes when performing submaximal catch-less derivatives..
Assuntos
Força Muscular , Levantamento de Peso , Fenômenos Biomecânicos , Força da Mão , Humanos , Masculino , Músculo EsqueléticoRESUMO
Non-local muscle fatigue (NLMF) studies have examined crossover impairments of maximal voluntary force output in non-exercised, contralateral muscles as well as comparing upper and lower limb muscles. Since prior studies primarily investigated contralateral muscles, the purpose of this study was to compare NLMF effects on elbow flexors (EF) and plantar flexors (PF) force and activation (electromyography: EMG). Secondly, possible differences when testing ipsilateral or contralateral muscles with a single or repeated isometric maximum voluntary contractions (MVC) were also investigated. Twelve participants (six males: (27.3 ± 2.5 years, 186.0 ± 2.2 cm, 91.0 ± 4.1 kg; six females: 23.0 ± 1.6 years, 168.2 ± 6.7 cm, 60.0 ± 4.3 kg) attended six randomized sessions where ipsilateral or contralateral PF or EF MVC force and EMG activity (root mean square) were tested following a dominant knee extensors (KE) fatigue intervention (2×100s MVC) or equivalent rest (control). Testing involving a single MVC (5s) was completed by the ipsilateral or contralateral PF or EF prior to and immediately post-interventions. One minute after the post-intervention single MVC, a 12×5s MVCs fatigue test was completed. Two-way repeated measures ANOVAs revealed that ipsilateral EF post-fatigue force was lower (-6.6%, p = 0.04, d = 0.18) than pre-fatigue with no significant changes in the contralateral or control conditions. EF demonstrated greater fatigue indexes for the ipsilateral (9.5%, p = 0.04, d = 0.75) and contralateral (20.3%, p < 0.01, d = 1.50) EF over the PF, respectively. There were no significant differences in PF force, EMG or EF EMG post-test or during the MVCs fatigue test. The results suggest that NLMF effects are side and muscle specific where prior KE fatigue could hinder subsequent ipsilateral upper body performance and thus is an important consideration for rehabilitation, recreation and athletic programs.
Assuntos
Cotovelo/fisiologia , Pé/fisiologia , Fadiga Muscular/fisiologia , Músculo Quadríceps/fisiologia , Adulto , Eletromiografia , Feminino , Humanos , Joelho/fisiologia , Masculino , Contração Muscular , Adulto JovemRESUMO
Post-activation performance enhancement (PAPE) is an improvement to voluntary muscle performance following a conditioning activity. There is evidence of fatigue resistance deficits in non-exercised muscles following unilateral fatiguing exercise of a contralateral muscle. The purpose of this study was to determine if a unilateral conditioning exercise protocol could induce PAPE in a contralateral, non-exercised muscle in young healthy adults. Thirty-two recreationally trained (n = 16) and athletically trained (n = 16) participants (16 males; age: 22.9 ± 2.03 years; height: 1.81 ± 0.06 m; weight: 82.8 ± 9.43 kg, and 16 females; age: 23.1 ± 2.80 years; height: 1.67 ± 0.07 m; weight: 66.4 ± 11.09 kg) were randomly allocated into two groups (dominant or non-dominant limb intervention). The experimental intervention, involved a conditioning exercise (4-repetitions of 5-seconds knee extension maximal voluntary isometric contractions: MVIC) with either the dominant (DOM) (n = 16) or non-dominant (ND) (n = 16) knee extensors with testing of the same (exercised) or contralateral (non-exercised) leg as well as a control (no conditioning exercise: n = 32) condition. Testing was performed before, 1-minute and 10-minutes after a high intensity, low volume, conditioning protocol (2 sets of 2x5-s MVIC). Pre- and post-testing included MVIC force and F100 (force developed in the first 100 ms: a proxy measure of rate of force development) and unilateral drop jump (DJ) height and contact time. There were no significant MVIC peak force or EMG nor DJ height or contact time interactions (intervention x limb dominance x time). The pre-test (0.50 ± 0.13) dominant leg MVIC F100 forces exceeded (p = 0.02) both post-test and post-10 min by a small magnitude 8.7% (d = 0.31). There was also a significant (p = 0.02) time x intervention leg x testing leg intervention, although it was observed that the control condition was as likely to demonstrate small to large magnitude changes as were the dominant and non-dominant legs. Following the conditioning activity, there was no significant evidence for non-local improvements (PAPE), or performance decreases.
Assuntos
Músculo Esquelético/fisiologia , Condicionamento Físico Humano/métodos , Condicionamento Físico Humano/fisiologia , Desempenho Físico Funcional , Eletromiografia , Humanos , Contração Isométrica , Joelho/fisiologia , Masculino , Fadiga Muscular/fisiologia , Adulto JovemRESUMO
It is widely believed that lifting heavy loads slowly, but with a conscious intention to move at high velocity, can produce resistance training (RT) adaptations indicative of rapid movements. This study investigated the effects of verbally cued high "intended" movement velocity (HIMV) during RT on neuromuscular and performance outcomes. 20 untrained volunteers (aged 24.2 ± 3.9 years) participated in 3 weeks of knee extension training. Participants were randomly allocated to receive verbal cues focusing on high intended movement velocity, HIMV, or steady and controlled movement, TRAD (traditional training). All other training variables, including actual movement velocity (30° s-1 ), remained constant. Increase in mean power output at 30° s-1 was greater for TRAD than HIMV (76% and 33%, respectively, P = 0.027). There were main effects for time (but no between-group differences) for maximal isometric force (+14%, P = 0.003), peak torque at 180° s-1 (+22%, P = 0.006), peak torque at 30° s-1 (+29%, P < 0.001), 3-repetition maximum (+20%, P < 0.001), and resting corticospinal excitability (+43%, P = 0.017). There were no differences between groups or across time for voluntary activation (P = 0.793), spinal excitability (P = 0.686), or intracortical inhibition (all P > 0.05). HIMV verbal cueing did not produce additional neurophysiological or performance benefits when compared to traditional cueing. Overall, our results demonstrated that verbal cueing did not alter the principle of velocity-specific adaptation. Cueing that increases the duration of maximal effort may be optimal for maximizing average power output at low speeds.