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1.
Glob Chang Biol ; 30(3): e17212, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38450825

RESUMO

Heterotrophic soil microorganisms are responsible for ~50% of the carbon dioxide released by respiration from the terrestrial biosphere each year. The respiratory response of soil microbial communities to warming, and the control mechanisms, remains uncertain, yet is critical to understanding the future land carbon (C)-climate feedback. Individuals of nine species of fungi decomposing wood were exposed to 90 days of cooling to evaluate the medium-term effect of temperature on respiration. Overall, the effect of temperature on respiration increased in the medium term, with no evidence of compensation. However, the increasing effect of temperature on respiration was lost after correcting for changes in biomass. These results indicate that C loss through respiration of wood-decomposing fungi will increase beyond the direct effects of temperature on respiration, potentially promoting greater C losses from terrestrial ecosystems and a positive feedback to climate change.


Assuntos
Fungos , Temperatura , Madeira , Mudança Climática , Fungos/fisiologia , Microbiota , Solo , Madeira/microbiologia
2.
Int J Behav Nutr Phys Act ; 20(1): 35, 2023 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-36964597

RESUMO

BACKGROUND: Over the last decade use of raw acceleration metrics to assess physical activity has increased. Metrics such as Euclidean Norm Minus One (ENMO), and Mean Amplitude Deviation (MAD) can be used to generate metrics which describe physical activity volume (average acceleration), intensity distribution (intensity gradient), and intensity of the most active periods (MX metrics) of the day. Presently, relatively little comparative data for these metrics exists in youth. To address this need, this study presents age- and sex-specific reference percentile values in England youth and compares physical activity volume and intensity profiles by age and sex. METHODS: Wrist-worn accelerometer data from 10 studies involving youth aged 5 to 15 y were pooled. Weekday and weekend waking hours were first calculated for youth in school Years (Y) 1&2, Y4&5, Y6&7, and Y8&9 to determine waking hours durations by age-groups and day types. A valid waking hours day was defined as accelerometer wear for ≥ 600 min·d-1 and participants with ≥ 3 valid weekdays and ≥ 1 valid weekend day were included. Mean ENMO- and MAD-generated average acceleration, intensity gradient, and MX metrics were calculated and summarised as weighted week averages. Sex-specific smoothed percentile curves were generated for each metric using Generalized Additive Models for Location Scale and Shape. Linear mixed models examined age and sex differences. RESULTS: The analytical sample included 1250 participants. Physical activity peaked between ages 6.5-10.5 y, depending on metric. For all metrics the highest activity levels occurred in less active participants (3rd-50th percentile) and girls, 0.5 to 1.5 y earlier than more active peers, and boys, respectively. Irrespective of metric, boys were more active than girls (p < .001) and physical activity was lowest in the Y8&9 group, particularly when compared to the Y1&2 group (p < .001). CONCLUSIONS: Percentile reference values for average acceleration, intensity gradient, and MX metrics have utility in describing age- and sex-specific values for physical activity volume and intensity in youth. There is a need to generate nationally-representative wrist-acceleration population-referenced norms for these metrics to further facilitate health-related physical activity research and promotion.


Assuntos
Acelerometria , Punho , Humanos , Masculino , Adolescente , Feminino , Criança , Valores de Referência , Benchmarking , Exercício Físico , Inglaterra
3.
Support Care Cancer ; 31(8): 471, 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37458858

RESUMO

PURPOSE: Physical activity can improve health outcomes for cancer patients; however, only 30% of patients are physically active. This review explored barriers to and facilitators of physical activity promotion and participation in patients living with and beyond cancer. Secondary aims were to (1) explore similarities and differences in barriers and facilitators experienced in head and neck cancer versus other cancers, and (2) identify how many studies considered the influence of socioeconomic characteristics on physical activity behaviour. METHODS: CINAHL Plus, MEDLINE, PsycINFO, Scopus and Cochrane (CDSR) were searched for qualitative and mixed methods evidence. Quality assessment was conducted using the Mixed Methods Appraisal Tool and a Critical Appraisal Skills Programme Tool. Thematic synthesis and frequency of reporting were conducted, and results were structured using the Capability-Opportunity-Motivation-Behaviour model and Theoretical Domains Framework. RESULTS: Thirty qualitative and six mixed methods studies were included. Socioeconomic characteristics were not frequently assessed across the included studies. Barriers included side effects and comorbidities (physical capability; skills) and lack of knowledge (psychological capability; knowledge). Having a dry mouth or throat and choking concerns were reported in head and neck cancer, but not across other cancers. Facilitators included improving education (psychological capability; knowledge) on the benefits and safety of physical activity. CONCLUSION: Educating patients and healthcare professionals on the benefits and safety of physical activity may facilitate promotion, uptakeand adherence. Head and neck cancer patients experienced barriers not cited across other cancers, and research exploring physical activity promotion in this patient group is required to improve physical activity engagement.


Assuntos
Exercício Físico , Neoplasias de Cabeça e Pescoço , Humanos , Adulto , Neoplasias de Cabeça e Pescoço/terapia , Pessoal de Saúde , Motivação , Pescoço , Pesquisa Qualitativa
4.
J Sports Sci ; 41(12): 1218-1230, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37811806

RESUMO

This study aimed to test the hypothesis that the total daily energy expenditure (TDEE) of male academy soccer players is greater than players not enrolled on a formalised academy programme. English Premier League academy (ACAD: n = 8, 13 years, 50 ± 6 kg, 88 ± 3% predicted adult stature, PAS) and non-academy players (NON-ACAD: n = 6, 13 years, 53 ± 12 kg, 89 ± 3% PAS) were assessed for TDEE (via doubly labelled water) during a 14-day in-season period. External loading was evaluated during training (ACAD: 8 sessions, NON-ACAD: 2 sessions) and games (2 games for both ACAD and NON-ACAD) via GPS, and daily physical activity was evaluated using triaxial accelerometry. Accumulative duration of soccer activity (ACAD: 975 ± 23 min, NON-ACAD: 397 ± 2 min; p < 0.01), distance covered (ACAD: 54.2 ± 8.3 km, NON-ACAD: 21.6 ± 4.7 km; p < 0.05) and time engaged in daily moderate-to-vigorous (ACAD: 124 ± 17 min, NON-ACAD: 79 ± 18 min; p < 0.01) activity was greater in academy players. Academy players displayed greater absolute (ACAD: 3380 ± 517 kcal · d-1, NON-ACAD: 2641 ± 308 kcal · d-1; p < 0.05) and relative TDEE (ACAD: 66 ± 6 kcal · kg · d-1, NON-ACAD: 52 ± 10 kcal · kg · d-1; p < 0.05) versus non-academy players. Given the injury risk associated with high training volumes during growth and maturation, data demonstrate the requirement for academy players to consume sufficient energy (and carbohydrate) intake to support the enhanced energy cost of academy programmes.


Assuntos
Ingestão de Energia , Futebol , Humanos , Adulto , Masculino , Água , Carboidratos da Dieta , Exercício Físico
5.
J Intellect Disabil ; : 17446295231203764, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37729890

RESUMO

Motor competence is important for lifelong physical activity (PA). The current study aimed to examine associations between PA and motor competence. In total, 43 children aged 7-12 years with intellectual disabilities and/or autism spectrum disorder completed anthropometric measures, the Bruininks-Oseretsky Test of Motor Proficiency-2, and wore a wrist accelerometer to capture total PA, moderate-to-vigorous PA (MVPA), average acceleration, and intensity gradient. No significant associations were found between PA outcomes and motor competence. Motor competence performance was commonly 'below average' or 'average'. The weakest subtests were upper limb coordination and strength. The strongest subtest was running speed and agility. Total weekly MVPA was 336.1 ± 150.3 min, higher than UK recommendations of 120-180 per week for disabled children and young people. Larger scale studies are needed to better understand the relationship between PA and motor competence. Future research should also consider the influence of environmental factors on PA in this group.

6.
Proc Biol Sci ; 289(1968): 20212622, 2022 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-35105237

RESUMO

Biological communities within living organisms are structured by their host's traits. How host traits affect biodiversity and community composition is poorly explored for some associations, such as arthropods within fungal fruit bodies. Using DNA metabarcoding, we characterized the arthropod communities in living fruit bodies of 11 wood-decay fungi from boreal forests and investigated how they were affected by different fungal traits. Arthropod diversity was higher in fruit bodies with a larger surface area-to-volume ratio, suggesting that colonization is crucial to maintain arthropod populations. Diversity was not higher in long-lived fruit bodies, most likely because these fungi invest in physical or chemical defences against arthropods. Arthropod community composition was structured by all measured host traits, namely fruit body size, thickness, surface area, morphology and toughness. Notably, we identified a community gradient where soft and short-lived fruit bodies harboured more true flies, while tougher and long-lived fruit bodies had more oribatid mites and beetles, which might reflect different development times of the arthropods. Ultimately, close to 75% of the arthropods were specific to one or two fungal hosts. Besides revealing surprisingly diverse and host-specific arthropod communities within fungal fruit bodies, our study provided insight into how host traits structure communities.


Assuntos
Artrópodes , Animais , Biodiversidade , Código de Barras de DNA Taxonômico , Frutas , Madeira
7.
Mol Ecol ; 31(11): 3241-3253, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35363919

RESUMO

During decomposition of organic matter, microbial communities may follow different successional trajectories depending on the initial environment and colonizers. The timing and order of the species arrival (assembly history) can lead to divergent communities through priority effects. We explored how assembly history and resource quality affected fungal communities and decay rate of decomposing wood, 1.5 and 4.5 years after tree felling. Additionally, we investigated the effect of invertebrate exclusion during the first two summers. We measured initial resource quality of bark and wood of aspen (Populus tremula) logs and surveyed the fungal communities by DNA metabarcoding at different times during succession. We found that gradients in fungal community composition were related to resource quality and we discuss how this may reflect different fungal life history strategies. As with previous studies, the initial amount of bark tannins was negatively correlated with wood decomposition rate over 4.5 years. The initial fungal community explained variation in community composition after 1.5, but not 4.5, years of succession. Although the assembly history of initial colonizers may cause alternative trajectories in successional communities, our results indicate that the communities may converge with the arrival of secondary colonizers. We also identified a strong legacy of invertebrate exclusion on fungal communities, even after 4.5 years of succession, thereby adding crucial knowledge on the importance of invertebrates in affecting fungal community development. By measuring and manipulating aspects of assembly history and resource quality that have rarely been studied, we expand our understanding of the complexity of fungal community dynamics.


Assuntos
Micobioma , Madeira , Animais , Fungos/genética , Invertebrados , Árvores , Madeira/microbiologia
8.
BMC Public Health ; 22(1): 40, 2022 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-34991510

RESUMO

BACKGROUND: Children with disabilities often engage in less than the recommended amount of daily physical activity (PA). Classroom-based PA breaks are a favourable method of promoting PA for children. However, evaluations of these programs in specialist schools are scarce, with even less research into their feasibility and acceptability. This may hinder effective implementation and program scalability. This pilot study investigated the feasibility and acceptability of implementing a classroom-based PA break program in Australian specialist school classrooms, using the Australian Joy of Moving (AJoM) program. METHODS: Forty primary/junior classes and their teachers across five specialist schools implemented the AJoM program for eight weeks as the intervention group within a pilot cluster randomised controlled trial. A mixed-methods design investigated classroom teachers' (N = 22; 6 males, 16 females) perspectives of the feasibility and acceptability of the program after implementation through semi-structured telephone interviews (n = 7 teachers), qualitative survey responses (n = 18 teachers) and quantitative survey items (n = 19 teachers). Qualitative data were analysed using predominantly deductive thematic analysis. Quantitative data were analysed using descriptive statistics. RESULTS: Classroom-based PA breaks may be feasible for getting children with disabilities more active at school. However, considerable variation exists in teachers' perception of the AJoM experience. While several teachers indicate that the program content could be pertinent for their class, common divergences in perceptions of feasibility and acceptability appear to relate to the age and developmental level or needs of the students in the class. CONCLUSIONS: This study provides preliminary evidence for the feasibility and acceptability of implementing classroom-based PA breaks in specialist schools. However, results demonstrate the importance of (1) allowing a high level of flexibility in the design and implementation of programs to meet the varying needs of class groups and (2) providing a large variety of resources to cater to the heterogeneity of the children. TRIAL REGISTRATION: This trial was prospectively registered with the Australian New Zealand Clinical Trials Registry ( ACTRN12619000193178 ) on 11 February 2019.


Assuntos
Exercício Físico , Instituições Acadêmicas , Austrália , Criança , Exercício Físico/fisiologia , Estudos de Viabilidade , Feminino , Humanos , Masculino , Projetos Piloto , Avaliação de Programas e Projetos de Saúde , Serviços de Saúde Escolar
9.
J Sports Sci ; 40(16): 1837-1848, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36018045

RESUMO

An understanding of physical activity (PA) and related health benefits remains limited in adults with Cystic Fibrosis (CF). Raw acceleration data metrics may improve the quality of assessment and further this understanding. The study aimed to compare PA between people with CF (pwCF) and non-CF peers and examine associations between PA, vascular function and health outcome measures. PA was assessed in 62 participants (31 pwCF) using ActiGraph accelerometers. Vascular function (a marker of cardiovascular disease risk) was assessed using flow-mediated dilatation (FMD) in sub-groups of pwCF (n = 12) and matched controls. Average Euclidean norm minus one (ENMO) (total PA) was significantly lower (p = 0.005) in pwCF (35.09 ± 10.60 mg), than their non-CF peers (44.62 ± 13.78 mg). PwCF had PA profiles (intensity gradient) indicative of more time in lower intensity activity (-2.62 ± 0.20, -2.37 ± 0.23). Vigorous activity was positively associated with lung function (rs = 0.359) and Quality of Life (r = 0.412). There were no significant differences (p = 0.313) in FMD% between pwCF (5.29 ± 2.76%) and non-CF peers (4.34 ± 1.58%) and no associations with PA. PwCF engaged in less moderate-to-vigorous PA and demonstrated a steeper PA profile than their non-CF peers.


Assuntos
Fibrose Cística , Adulto , Humanos , Qualidade de Vida , Exercício Físico , Aceleração
10.
Pediatr Exerc Sci ; 33(1): 40-47, 2021 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-33771944

RESUMO

PURPOSE: To examine (1) associations between body fat percent (BF) and lifestyle behaviors in children aged 9-11 years and (2) the consistency of these associations over a 10-year period. METHODS: In this repeat, cross-sectional study, 15,977 children aged 9-11 years completed an anthropometric assessment and the SportsLinx Lifestyle survey between 2004 and 2013. Body fat was estimated according to the sum of the triceps and subscapular skinfold measurements. Multilevel models were utilized to examine associations between BF and responses to the lifestyle survey while controlling for known covariates. RESULTS: Lifestyle behaviors explained 8.6% of the total variance in body fat. Specifically, negative associations were found between BF and active transport to school ( ß = -0.99 [0.19], P < .001), full-fat milk (-0.07 [0.15], P < .001), and sweetened beverage consumption (-0.40 [0.15], P = .007). Relative to the reference group of ≤8:00 PM, later bedtime was positively associated with BF: 8:00 to 8:59 PM ( ß = 1.60 [0.26], P < .001); 9:00 to 10:00 PM ( ß = 1.04 [0.24], P < .001); ≥10:00 PM ( ß = 1.18 [0.30], P < .001). Two-way interactions revealed opposing associations between BF and the consumption of low-calorie beverages for boys ( ß = 0.95 [0.25], P < .001) and girls ( ß = -0.85 [0.37], P = .021). There was no significant change in these associations over a 10-year period. CONCLUSIONS: In this population-level study covering a decade of data collection, lifestyle behaviors were associated with BF. Policies and interventions targeting population-level behavior change, such as active transport to school, sleep time, and consumption of full-fat milk, may offer an opportunity for improvements in BF.


Assuntos
Adiposidade , Estilo de Vida , Tecido Adiposo , Antropometria , Bebidas , Criança , Estudos Transversais , Dieta , Ingestão de Energia , Feminino , Humanos , Estudos Longitudinais , Masculino , Reino Unido
11.
J Insect Sci ; 21(5)2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34553221

RESUMO

Hollows of veteran trees (i.e., rot holes) provide habitat for many rare and threatened saproxylic invertebrates. Rot holes are highly heterogeneous, particularly in terms of substrate and microclimate conditions. There is, however, a dearth of information regarding the differences in biological communities inhabiting rot holes with different environmental conditions. Invertebrates were sampled from European beech (Fagus sylvatica) rot holes in Windsor, Savernake, and Epping Forests (United Kingdom). For each rot hole, physical and environmental conditions were measured, including tree diameter, rot hole dimensions, rot hole height, substrate density, water content, and water potential. These parameters were used to assess the influence of environmental conditions and habitat characteristics on invertebrate communities. Rot hole invertebrate communities were extremely diverse, containing both woodland generalist and saproxylic specialist taxa. Large variation in community structure was observed between rot holes and across woodlands; all sites supported threatened and endangered taxa. Environmental conditions in rot holes were highly variable within and between woodland sites, and communities were predominantly structured by these environmental conditions. In particular, turnover between invertebrate communities was linked to high ß-diversity. The linked heterogeneity of environmental conditions and invertebrate communities in rot holes suggests that management of deadwood habitats in woodlands should strive to generate environmental heterogeneity to promote invertebrate diversity. Additional research is required to define how management and conservation activities can further promote enhanced biodiversity across rot holes.


Assuntos
Biodiversidade , Florestas , Invertebrados , Animais , Biota , Conservação dos Recursos Naturais , Ecossistema , Fagus , Árvores
12.
Glob Chang Biol ; 2020 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-33230837

RESUMO

Temperatures approaching or exceeding 20°C have been measured during summer in polar regions at the surfaces of barren fellfield soils under cloudless skies around solar noon. However, despite the upper temperature limit for the growth of cold-adapted microbes-which are abundant in polar soils and have pivotal roles in nutrient cycling-typically being close to this temperature, previous studies have not addressed the consequences of climate change for the metabolism of these organisms in the natural environment. Here in a 5-year field experiment on Alexander Island in the southern maritime Antarctic, we show that the abundance of Pseudogymnoascus roseus, the most widespread decomposer fungus in maritime Antarctic fellfield soils, is reduced by 1-2 orders of magnitude when irrigated and nutrient-amended soils are warmed to >20°C during summer. Laboratory experiments under conditions mimicking those during midsummer in the natural environment indicated that the hyphal extension rates of P. roseus isolates and the activities of five extracellular enzymes are reduced by 54%-96% at high water availability after exposure to temperatures cycling daily from 2 to 21°C and 2 to 24°C, relative to temperatures cycling from 2 to 18°C. Given that the temperatures of surface soils at the study site already reach 19°C during midsummer, the observations reported here suggest that, at predicted rates of warming arising from moderate greenhouse gas emissions, inhibitory effects of climate change on the metabolism of P. roseus could manifest themselves within the next few decades. Furthermore, with peak temperatures at the surfaces of fellfield soils at other maritime Antarctic locations and in High Arctic and alpine regions already exceeding 20°C during summer, the observations suggest that climate warming has the potential to inhibit the growth of other cold-adapted microbes, with negative effects on soils as the Earth's climate continues to warm.

13.
Scand J Med Sci Sports ; 30(1): 117-125, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31593604

RESUMO

The aims were to (a) investigate associations between a novel accelerometer metric: the minimum acceleration value above which the most active 30-minutes were accumulated during the school day (M30ACC ), and health indicators, and (b) demonstrate that applying an equivalent cut-point to the M30ACC metric gives comparable prevalence results as a moderate-to-vigorous physical activity (MVPA) cut-point approach. Two hundred and ninety-six children (age 9-10-years) wore wrist-mounted accelerometers for 7-days. School day MVPA and M30ACC were calculated. Body mass index (BMI), waist-to-height ratio (WHtR), and cardiorespiratory fitness (CRF) were also measured. Mixed linear models investigated associations between M30ACC and health indicators. Agreement between ranked MVPA and M30ACC values was assessed using percent agreement, kappa, sensitivity, and specificity statistics. M30ACC thresholds associated with health indicators were 213 mg (BMI), 206 mg (WHtR), and 269 mg (CRF) for girls. The equivalent values for boys were 234 mg (BMI), 230 mg (WHtR), and 327 mg (CRF). Less than half of girls and 75% of boys accumulated 30 minutes of school day MVPA. Just <50% of girls and >80% of boys had M30ACC values ≥200 mg, which is equivalent to brisk walking. Agreement between MVPA and M30ACC tertiles was high, reflected by the sensitivity and specificity values of >90%. Results demonstrate the utility of M30ACC as a PA metric that is not heavily influenced by researcher decisions. M30ACC has potential as an accelerometer-specific metric for generating PA guidelines related to health indicators and easily understood forms of activity such as brisk walking.


Assuntos
Acelerometria/métodos , Exercício Físico , Índice de Massa Corporal , Aptidão Cardiorrespiratória , Criança , Estudos Transversais , Inglaterra , Feminino , Humanos , Masculino , Instituições Acadêmicas , Classe Social , Fatores de Tempo , Razão Cintura-Estatura
14.
J Sports Sci ; 38(9): 1036-1045, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32228156

RESUMO

This study validated sedentary behaviour (SB), moderate-to-vigorous physical activity (MVPA) and vigorous physical activity (VPA) accelerometer cut-points in 5-7-year-old children. Participants (n = 49, 55% girls) wore an ActiGraph GT9X accelerometer, recording data at 100 Hz downloaded in 1 s epochs, on both wrists and the right hip during a standardised protocol and recess. Cut-points were generated using ROC analysis with direct observation as a criterion. Subsequently, cut-points were optimised using Confidence intervals equivalency analysis and then cross-validated in a cross-validation group. SB cut-points were 36 mg (Sensitivity (Sn) = 79.8%, Specificity (Sp) = 56.8%) for non-dominant wrist, 39 mg (Sn = 75.4%, Sp = 70.2%) for dominant wrist and 20 mg (Sn = 78%, Sp = 50.1%) for hip. MVPA cut-points were 189 mg (Sn = 82.6%, Sp = 78%) for non-dominant wrist, 181 mg (Sn = 79.1%, Sp = 76%) for dominant wrist and 95 mg (Sn = 79.3%, Sp = 75.6%) for hip. VPA cut-points were 536 mg (Sn = 75.1%, Sp = 68.7%) for non-dominant wrist, 534 mg (Sn = 67.6%, Sp = 95.6%) for dominant wrist and 325 mg (Sn = 78.2%, Sp = 96.1%) for hip. All placements demonstrated adequate levels of accuracy for SB and PA assessment.


Assuntos
Acelerometria/métodos , Exercício Físico , Monitores de Aptidão Física , Comportamento Sedentário , Criança , Pré-Escolar , Feminino , Quadril , Humanos , Masculino , Curva ROC , Reprodutibilidade dos Testes , Punho
15.
J Sports Sci ; 37(18): 2159-2167, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31156048

RESUMO

Average acceleration (AvAcc) and intensity gradient (IG) have been proposed as standardised metrics describing physical activity (PA) volume and intensity, respectively. We examined hypothesised between-group PA differences in AvAcc and IG, and their associations with health and well-being indicators in children. ActiGraph GT9X wrist accelerometers were worn for 24-h·d-1 over 7days by 145 children aged 9-10. Raw accelerations were averaged per 5-s epoch to represent AvAcc over 24-h. IG represented the relationship between log values for intensity and time. Moderate-to-vigorous PA (MVPA) was estimated using youth cutpoints. BMI z-scores, waist-to-height ratio (WHtR), peak oxygen uptake (VO2peak), Metabolic Syndrome risk (MetS score), and well-being were assessed cross-sectionally, and 8-weeks later. Hypothesised between-group differences were consistently observed for IG only (p < .001). AvAcc was strongly correlated with MVPA (r = 0.96), while moderate correlations were observed between IG and MVPA (r = 0.50) and AvAcc (r = 0.54). IG was significantly associated with health indicators, independent of AvAcc (p < .001). AvAcc was associated with well-being, independent of IG (p < .05). IG was significantly associated with WHtR (p < .01) and MetS score (p < .05) at 8-weeks follow-up. IG is sensitive as a gauge of PA intensity that is independent of total PA volume, and which relates to important health indicators in children.


Assuntos
Aceleração , Exercício Físico , Acelerometria/instrumentação , Índice de Massa Corporal , Aptidão Cardiorrespiratória , Criança , Estudos Transversais , Feminino , Monitores de Aptidão Física , Humanos , Masculino , Síndrome Metabólica , Consumo de Oxigênio , Obesidade Infantil , Projetos Piloto , Qualidade de Vida , Classe Social , Tiazinas , Razão Cintura-Estatura , Punho
16.
J Sports Sci ; 37(16): 1919-1925, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30999815

RESUMO

This study used accelerometer and self-report measures of overall sedentary time (ST) and screen time behaviours to examine their respective associations with adiposity among UK youth. Participants (Year groups 5, 8, and 10; n=292, 148 girls) wore the SenseWear Armband Mini accelerometer for eight days and completed the Youth Activity Profile, an online report tool designed to estimate physical activity and ST.Stature, body mass and waist circumference were measured to classify adiposity outcomes (overweight/obese and central obesity). One-way between groups ANOVA and adjusted linear, logistic and multinomial logistic regression analyses were conducted. There was a significant main effect of age on total ST across the whole week (F(2, 289)=41.64, p≤0.001). ST increased monotonically across Year 5 (581.09±107.81 min·d-¹), 8 (671.96±112.59 min·d-¹) and 10 (725.80±115.20 min·d-¹), and all pairwise comparisons were significant at p≤0.001. A steep age-related gradient to mobile phone use was present (p≤0.001). ST was positively associated with adiposity outcomes independent of moderate-to-vigorous intensity physical activity (MVPA; p≤0.001). Engaging in >3 hours of video gaming daily was positively associated with central obesity (OR=2.12, p≤0.05) but not after adjustment for MVPA. Results further demonstrate the importance of reducing overall ST to maintain healthy weight status among UK youth.


Assuntos
Acelerometria , Adiposidade , Monitores de Aptidão Física , Comportamento Sedentário , Autorrelato , Acelerometria/instrumentação , Adolescente , Estatura , Índice de Massa Corporal , Inglaterra , Exercício Físico , Feminino , Humanos , Masculino , Análise de Regressão , Jogos de Vídeo , Circunferência da Cintura
17.
J Sports Sci ; 37(11): 1270-1279, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30558487

RESUMO

Wrist-based accelerometers are now common in assessing physical activity (PA) and sedentary behaviour (SB) in population-based studies, but there is a scarcity of raw acceleration cutpoints in older adults. The study aimed to determine and evaluate wrist-based GENEActiv (GA) and hip-based ActiGraph GT3X+ (AG) raw acceleration cutpoints for SB and moderate-to-vigorous PA (MVPA) in older adults ≥60 years of age. A laboratory-based calibration analyses of 34 healthy older adults involved receiver operator characteristic (ROC) curves to determine raw acceleration cutpoints for SB and MVPA. ROC analysis revealed an area under the curve (AUC) of 0.88 for GA SB and MVPA, and 0.90 for AG SB and 0.94 for AG MVPA. Sensitivity optimised SB and specificity optimised MVPA GA cutpoints of 57 mg and 104 mg, and AG cutpoints of 15 mg and 69 mg were also generated, respectively. Cross-validation analysis revealed moderate agreement for GA and AG SB cutpoints, and fair to substantial agreement for GA and AG MVPA cutpoints, respectively. The resultant cutpoints can classify older adults as engaging in SB or not engaging in MVPA but the sensitivity optimised SB cutpoints should be interpreted with a degree of caution due to their modest cross-validation results.


Assuntos
Actigrafia/métodos , Actigrafia/normas , Exercício Físico , Monitores de Aptidão Física , Quadril/fisiologia , Comportamento Sedentário , Punho/fisiologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Índice de Massa Corporal , Calibragem , Metabolismo Energético , Feminino , Monitores de Aptidão Física/normas , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Reprodutibilidade dos Testes
18.
J Sports Sci ; 37(16): 1910-1918, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31012798

RESUMO

This study aimed to validate the Sedentary Sphere posture classification method from wrist-worn accelerometers in children. Twenty-seven 9-10-year-old children wore ActiGraph GT9X (AG) and GENEActiv (GA) accelerometers on both wrists, and activPAL on the thigh while completing prescribed activities: five sedentary activities, standing with a phone, walking (criterion for all 7: observation) and 10-min free-living play (criterion: activPAL). In an independent sample, 21 children wore AG and GA accelerometers on the non-dominant wrist and activPAL for two days of free-living. Per cent accuracy, pairwise 95% equivalence tests (±10% equivalence zone) and intra-class correlation coefficients (ICC) analyses were completed. Accuracy was similar, for prescribed activities irrespective of brand (non-dominant wrist: 77-78%; dominant wrist: 79%). Posture estimates were equivalent between wrists within brand (±6%, ICC > 0.81, lower 95% CI ≥ 0.75), between brands worn on the same wrist (±5%, ICC ≥ 0.84, lower 95% CI ≥ 0.80) and between brands worn on opposing wrists (±6%, ICC ≥ 0.78, lower 95% CI ≥ 0.72). Agreement with activPAL during free-living was 77%, but sedentary time was underestimated by 7% (GA) and 10% (AG). The Sedentary Sphere can be used to classify posture from wrist-worn AG and GA accelerometers for group-level estimates in children, but future work is needed to improve the algorithm for better individual-level results.


Assuntos
Actigrafia/instrumentação , Monitores de Aptidão Física , Postura , Comportamento Sedentário , Atividades Cotidianas , Algoritmos , Criança , Desenho de Equipamento , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Coxa da Perna , Punho
19.
Ecology ; 99(6): 1306-1315, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29655179

RESUMO

Here we assess the impact of geographically dependent (latitude, longitude, and altitude) changes in bioclimatic (temperature, precipitation, and primary productivity) variability on fungal fruiting phenology across Europe. Two main nutritional guilds of fungi, saprotrophic and ectomycorrhizal, were further separated into spring and autumn fruiters. We used a path analysis to investigate how biogeographic patterns in fungal fruiting phenology coincided with seasonal changes in climate and primary production. Across central to northern Europe, mean fruiting varied by approximately 25 d, primarily with latitude. Altitude affected fruiting by up to 30 d, with spring delays and autumnal accelerations. Fruiting was as much explained by the effects of bioclimatic variability as by their large-scale spatial patterns. Temperature drove fruiting of autumnal ectomycorrhizal and saprotrophic groups as well as spring saprotrophic groups, while primary production and precipitation were major drivers for spring-fruiting ectomycorrhizal fungi. Species-specific phenology predictors were not stable, instead deviating from the overall mean. There is significant likelihood that further climatic change, especially in temperature, will impact fungal phenology patterns at large spatial scales. The ecological implications are diverse, potentially affecting food webs (asynchrony), nutrient cycling and the timing of nutrient availability in ecosystems.


Assuntos
Clima , Ecossistema , Mudança Climática , Europa (Continente) , Estações do Ano
20.
Pediatr Exerc Sci ; 30(1): 81-89, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-27175903

RESUMO

PURPOSE: To assess the effects of the Children's Health, Activity and Nutrition: Get Educated! intervention on body size, body composition, and peak oxygen uptake in a subsample of 10- to 11-year-old children. METHODS: Sixty children were recruited from 12 schools (N = 6 intervention) to take part in the CHANGE! subsample study. Baseline, postintervention, and follow-up measures were completed in October 2010, March-April 2011, and June-July 2011, respectively. Outcome measures were body mass index z score, waist circumference, body composition assessed using dual-energy X-ray absorptiometry (baseline and follow-up only), and peak oxygen uptake. RESULTS: Significant differences in mean trunk fat mass (control = 4.72 kg, intervention = 3.11 kg, P = .041) and trunk fat % (control = 23.08%, intervention = 17.75%, P = .022) between groups were observed at follow-up. Significant differences in waist circumference change scores from baseline to follow-up were observed between groups (control = 1.3 cm, intervention = -0.2 cm, P = .023). Favorable changes in body composition were observed in the intervention group; however, none of these changes reached statistical significance. No significant differences in peak oxygen uptake were observed. CONCLUSIONS: The results of the present study suggest the multicomponent curriculum intervention had small to medium beneficial effects on body size and composition health outcomes.


Assuntos
Composição Corporal , Aptidão Cardiorrespiratória , Currículo , Promoção da Saúde/métodos , Absorciometria de Fóton , Índice de Massa Corporal , Criança , Feminino , Humanos , Masculino , Consumo de Oxigênio , Instituições Acadêmicas , Circunferência da Cintura
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