RESUMO
We aimed to investigate which among 20 cardiometabolic and performance outcomes do and do not respond to high-intensity interval training (HIT), resistance training (RT), or concurrent training (CT) in insulin-resistant adult women. A secondary aim was to report the training-induced changes and the prevalence of non-responders. Forty-five insulin-resistant adult women were randomly assigned to one of the following 4 groups: HIT (39.2 ± 9.5 years [y]; body mass index [BMI], 29.3 ± 3.3; n = 14), RT (33.9 ± 9.3 y; BMI, 29.4 ± 5.5; n = 8), CT (43.3 ± 8.1 y; BMI, 29.1 ± 2.9; n = 10), and a control group (CG, 40.1 ± 11.4 y; BMI, 28.3 ± 3.5; n = 13). Nine body composition, 3 cardiovascular, 3 metabolic, and 5 performance outcomes were assessed at baseline and after 12 weeks of intervention. Considering all outcomes, the lowest number of total non-responses for one or more variables was found in the RT group, followed by the CT and HIT groups. Individuals in the CG group were classified as non-responders for almost all the variables. Moreover, there were several significant changes in body composition and metabolic parameters, including fasting glucose (HIT: -5.7, RT -5.1 mg/d), fasting insulin (HIT: -0.6, RT -0.6 µIU/mL), and HOMA-IR (HIT: -0.3, RT -0.4), in addition to improvements in cardiovascular and performance parameters. Also, there were significant differences among groups in the prevalence of non-responders for the variables where a non-response was detected. Overall, the study suggests that independent of the mode of training including volume and frequency, RT has an important ability to reduce the prevalence of non-response to improve the 20 outcomes of health and performance in insulin-resistant adult women.
Assuntos
Exercício Físico/fisiologia , Resistência à Insulina , Adulto , Glicemia , Pressão Sanguínea , Composição Corporal , Índice de Massa Corporal , Aptidão Cardiorrespiratória , Feminino , Treinamento Intervalado de Alta Intensidade , Humanos , Pessoa de Meia-Idade , Força Muscular , Treinamento ResistidoRESUMO
The specific role of different strength measures on mortality risk needs to be clarified to gain a better understanding of the clinical importance of different muscle groups, as well as to inform intervention protocols in relation to reducing early mortality. The aim of the systematic review and meta-analysis was to determine the relationship between muscular strength and risk of cancer mortality. Eligible cohort studies were those that examined the association between muscular strength, as assessed using validated tests, and cancer mortality in healthy youth and adults. The hazard ratio (HR) estimates obtained were pooled using random effects meta-analysis models. The outcome was cancer mortality assessed using the HR (Cox proportional hazards model). Eleven prospective studies with 1 309 413 participants were included, and 9787 cancer-specific deaths were reported. Overall, greater handgrip (HR = 0.97, 95% CI, 0.92-1.02; P = .055; I2 = 18.9%) and knee extension strength (HR = 0.98, 95% CI, 0.95-1.00; P = .051; I2 = 60.6%) were barely significant associated with reduced risk of cancer mortality. Our study suggests that higher level of muscular strength is not statistically associated with lower risk of cancer mortality.
Assuntos
Força da Mão , Neoplasias/mortalidade , Humanos , Modelos de Riscos ProporcionaisRESUMO
The aim of the study was to summarize the evidence of the effects of reallocating time spent in sedentary behaviours in different activity intensities on youth's adiposity. Five databases were searched. Studies that reported the effects of replacing sedentary behaviour with light-intensity physical activity (LIPA) and/or moderate-to-vigorous physical activity (MVPA) on at least one adiposity parameter. The estimated regression coefficients (ß) and 95% CIs were combined and meta-analysed. Data from 7,351 youths and five studies were analysed. Pooled analysis from cross-sectional studies shows that replacing sedentary time with LIPA showed no significant associations with any adiposity-related outcomes. Replacing sedentary time with MVPA was statistically associated with total body fat percentage (ß = -2.512; p = 0.003), but not with body mass index or waist circumference. In subgroup analysis, the greatest magnitude of association was observed from studies where 60 min of sedentary behaviour was reallocated to 60 min of MVPA (ß = -4.535; p < 0.001). Our results highlight the importance of promoting MVPA, which may improve body composition phenotypes in young people. This information can be used to develop more effective lifestyle interventions.
Assuntos
Adiposidade/fisiologia , Índice de Massa Corporal , Exercício Físico/fisiologia , Comportamento Sedentário , Adolescente , Criança , Humanos , Circunferência da CinturaRESUMO
BACKGROUND AND AIMS: Studies in the paediatric population have shown inconsistent associations between cardiorespiratory fitness and inflammation independently of adiposity. The purpose of this study was (i) to analyse the combined association of cardiorespiratory fitness and adiposity with high-sensitivity C-reactive protein (hs-CRP), and (ii) to determine whether adiposity acts as a mediator on the association between cardiorespiratory fitness and hs-CRP in children and adolescents. METHODS AND RESULTS: This cross-sectional study included 935 (54.7% girls) healthy children and adolescents from Bogotá, Colombia. The 20 m shuttle run test was used to estimate cardiorespiratory fitness. We assessed the following adiposity parameters: body mass index, waist circumference, and fat mass index and the sum of subscapular and triceps skinfold thickness. High sensitivity assays were used to obtain hs-CRP. Linear regression models were fitted for mediation analyses examined whether the association between cardiorespiratory fitness and hs-CRP was mediated by each of adiposity parameters according to Baron and Kenny procedures. Lower levels of hs-CRP were associated with the best schoolchildren profiles (high cardiorespiratory fitness + low adiposity) (p for trend <0.001 in the four adiposity parameters), compared with unfit and overweight (low cardiorespiratory fitness + high adiposity) counterparts. Linear regression models suggest a full mediation of adiposity on the association between cardiorespiratory fitness and hs-CRP levels. CONCLUSIONS: Our findings seem to emphasize the importance of obesity prevention in childhood, suggesting that having high levels of cardiorespiratory fitness may not counteract the negative consequences ascribed to adiposity on hs-CRP.
Assuntos
Adiposidade , Biomarcadores/sangue , Proteína C-Reativa/análise , Aptidão Cardiorrespiratória , Mediadores da Inflamação/sangue , Inflamação/epidemiologia , Obesidade Infantil/epidemiologia , Adolescente , Fatores Etários , Criança , Colômbia/epidemiologia , Estudos Transversais , Feminino , Humanos , Inflamação/sangue , Inflamação/diagnóstico , Inflamação/prevenção & controle , Modelos Lineares , Masculino , Obesidade Infantil/diagnóstico , Obesidade Infantil/fisiopatologia , Obesidade Infantil/prevenção & controle , Prevalência , Fatores de RiscoRESUMO
The aims were to examine the association of sleep patterns with being overweight or obese and to analyze the association of cardiorespiratory fitness (CRF) with sleep patterns in children. The study involved 395 schoolchildren (12-13 years old). Sleep patterns were assessed with the Sleep Self-Report (SSR) questionnaire, grouped into four subscales: sleep quality, sleep-related anxiety, bedtime refusal, and sleep routines. CRF was predicted by the 20-m shuttle-run test. Logistic regression models showed that sleep-related anxiety problems predicted being overweight or obese in both sexes, and sleep quality problems predicted being overweight or obese in girls. Also, girls who had better CRF levels were less susceptible to sleep-related anxiety problems. Studies are required to determine if increasing CRF could be a possible strategy for improving sleep quality.
Assuntos
Aptidão Cardiorrespiratória/fisiologia , Obesidade/fisiopatologia , Autorrelato , Sono/fisiologia , Adolescente , Ansiedade/complicações , Índice de Massa Corporal , Criança , Chile , Feminino , Humanos , Modelos Logísticos , Masculino , Obesidade/complicações , Sobrepeso/complicações , Sobrepeso/fisiopatologia , Inquéritos e QuestionáriosRESUMO
BACKGROUND/OBJECTIVE: Adipokines are involved in the etiology of diabetes, insulin resistance, and the development of atherosclerosis and other latent-onset complications. The objective of this meta-analysis was to determine the effectiveness of exercise interventions on adipokines in pediatric obesity. SUBJECTS/METHODS: A computerized search was made using three databases. The analysis was restricted to studies that examined the effect of exercise interventions on adipokines (adiponectin, leptin, resistin and visfatin) in pediatric obesity (6-18 years old). Fourteen randomized controlled trials (347 youths) were included. Weighted mean difference (WMD) and 95% confidence intervals were calculated. RESULTS: Exercise was associated with a significant increase in adiponectin (WMD=0.882 µg ml-1, 95% CI, 0.271-1.493) but did not alter leptin and resistin level. Likewise, exercise intensity and change in body fat; as well as total exercise program duration, duration of the sessions, and change in body fat all significantly influenced the effect of exercise on adiponectin and leptin, respectively. CONCLUSIONS: Exercise seems to increase adiponectin levels in childhood obesity. Our results also suggested that exercise on its own, without the concomitant presence of changes in body composition levels, does not affect leptin levels.
Assuntos
Adipocinas/metabolismo , Exercício Físico , Obesidade Infantil/metabolismo , Adiponectina/metabolismo , Glicemia/metabolismo , Criança , Humanos , Resistência à Insulina/fisiologia , Obesidade Infantil/fisiopatologia , Obesidade Infantil/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
Low birth weight is associated with cognitive impairments persisting into adolescence and early adulthood. The purposes of this study was two-fold: to analyse the association between birth weight (BW) and school performance, and to determine the influence of adolescent aerobic capacity and muscular strength on the association between BW and school performance in children at 12-13 years. The study included 395 children (50.4% boys, aged 12-13 years). Self-reported BW was evaluated. We measured school performance (mean of the grades obtained in language and mathematics) and two physical fitness tests (aerobic capacity and muscular strength). Analysis of variance was used to analyse the differences in school performance according to BW categories (⩽2500, 2500-3500 and ⩾3500 g). Linear regression models fitted for mediation analyses examined whether the association between BW and school performance was mediated by aerobic capacity and/or muscular strength. Higher BW was associated with better school performance independent of current body mass index. These differences disappeared after controlling for aerobic capacity, which also mediated the association between BW and school performance (13.4%). The relationship between BW and school performance seems to be dependent on aerobic capacity fitness. Our results are of importance because the consequences of BW tend to continue into childhood, and current physical fitness of the children may potentially be modified to improve school performance.
Assuntos
Logro , Peso ao Nascer , Índice de Massa Corporal , Exercício Físico/fisiologia , Músculo Esquelético/fisiologia , Adolescente , Criança , Avaliação Educacional , Feminino , Humanos , MasculinoRESUMO
BACKGROUND: The scientific interest in high-intensity interval training (HIIT) has greatly increased during recent years. OBJECTIVE: The objective of this meta-analysis was to determine the effectiveness of HIIT interventions on cardio-metabolic risk factors and aerobic capacity in overweight and obese youth, in comparison with other forms of exercise. DATA SOURCES: A computerized search was made using seven databases. STUDY ELIGIBILITY CRITERIA: The analysis was restricted to studies that examined the effect of HIIT interventions on cardio-metabolic and/or aerobic capacity in pediatric obesity (6-17 years old). PARTICIPANTS AND INTERVENTIONS: Nine studies using HIIT interventions were selected (n = 274). STUDY APPRAISAL AND SYNTHESIS METHODS: Standarized mean difference (SMD) and 95% confidence intervals were calculated. The DerSimonian-Laird approach was used. RESULTS: HIIT interventions (4-12 week duration) produced larger decreases in systolic blood pressure (SMD = 0.39; -3.63 mmHg) and greater increases in maximum oxygen uptake (SMD = 0.59; 1.92 ml/kg/min) than other forms of exercise. Also, type of comparison exercise group and duration of study were moderators. CONCLUSIONS: HIIT could be considered a more effective and time-efficient intervention for improving blood pressure and aerobic capacity levels in obese youth in comparison to other types of exercise. © 2016 World Obesity.
Assuntos
Doenças Cardiovasculares/prevenção & controle , Treinamento Intervalado de Alta Intensidade , Síndrome Metabólica/prevenção & controle , Sobrepeso/terapia , Obesidade Infantil/terapia , Adolescente , Criança , Tolerância ao Exercício , Humanos , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
OBJECTIVE: Arterial stiffness is a contributor to the development of atherosclerosis and cardiovascular disease. The aim of the study was to analyse the relationship between sedentary behaviour and arterial stiffness in a Spanish adult population. METHODS: This cross-sectional study included 1365 subjects belonging to the EVIDENT project. Physical activity and sedentary behaviour were measured objectively over 7 days using ActiGraph accelerometers. Thresholds of 10 consecutive minutes were used to estimate the daily sedentary time in bouts ≥10 min. Each interruption in sedentary time (counts/min ≥100) was considered a break. Arterial stiffness was evaluated using the B-pro device through the following indicators: radial Augmentation Index (rAIx), Ambulatory Arterial Stiffness Index (AASI), and central and peripheral pulse pressure (PP). RESULTS: We found a positive relationship between central and peripheral pulse pressure (office, 24 h, awake and sleep PP) and total sedentary time. These arterial stiffness parameters were also associated with sedentary time in bouts ≥10 min. Significance disappeared in both cases, however, after adjusting for MVPA and breaks per sedentary hour. Adults who reported fewer breaks per sedentary hour (25th percentile < 2 n/day) had higher levels of AASI, awake and sleep PP. CONCLUSIONS: In a medium-sized sample of adult attenders of community clinics our data showed that it seems to be important to avoid prolonged uninterrupted periods of sedentary time.
Assuntos
Doenças Cardiovasculares/fisiopatologia , Comportamento Sedentário , Rigidez Vascular , Actigrafia/instrumentação , Adulto , Idoso , Idoso de 80 Anos ou mais , Pressão Sanguínea , Monitorização Ambulatorial da Pressão Arterial , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Atividade Motora , Medição de Risco , Fatores de Risco , Espanha/epidemiologia , Fatores de Tempo , Adulto JovemRESUMO
INTRODUCTION: Physical activity (PA), screen time (ST), and sleep are modifiable lifestyle habits for health. The objectives of this study were: a) to examine the association between PA, ST, and both, on sleep patterns; and b) to determine the influence of PA and ST on sleep problems in Chilean girls. PATIENTS AND METHODS: The study involved 196 children (12.2 years). Patterns and sleep problems were assessed using the Spanish version of the Sleep Self-Report, and the PA through the Physical Activity Questionnaire for Adolescents (PAQ-A), both in Castilian. The ST was assessed using several questions about television, game console and computer use. RESULTS: The ST recommendation (2h a day) was exceeded by 63.2% of the girls. In general, the most active girls (last quartile) that did not exceed the recommendations of ST reported higher sleep quality and total score values compared to those who did not meet both. The logistic regression analysis showed that girls who did not meet both habits were more likely to have sleep quality (odds ratio=17.8, P=.018), and general sleep problems (odds ratio=7.85, P=.025). CONCLUSIONS: Parents need to set limits on sedentary leisure time and encourage more active habits, as sleep is a parameter closely linked to a better health profile in youth.