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BACKGROUND AND AIMS: To investigate the efficacy and feasibility of three different 8 h time-restricted eating (TRE) schedules (i.e., early, late, and self-selected) compared to each other and to a usual-care (UC) intervention on visceral adipose tissue (VAT) and cardiometabolic health in men and women. METHODS AND RESULTS: Anticipated 208 adults (50% women) aged 30-60 years, with overweight/obesity (25 ≤ BMI<40 kg/m2) and with mild metabolic impairments will be recruited for this parallel-group, multicenter randomized controlled trial. Participants will be randomly allocated (1:1:1:1) to one of four groups for 12 weeks: UC, early TRE, late TRE or self-selected TRE. The UC group will maintain their habitual eating window and receive, as well as the TRE groups, healthy lifestyle education for weight management. The early TRE group will start eating not later than 10:00, and the late TRE group not before 13:00. The self-selected TRE group will select an 8 h eating window before the intervention and maintain it over the intervention. The primary outcome is changes in VAT, whereas secondary outcomes include body composition and cardiometabolic risk factors. CONCLUSION: This study will determine whether the timing of the eating window during TRE impacts its efficacy on VAT, body composition and cardiometabolic risk factors and provide insights about its feasibility.
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Doenças Cardiovasculares , Gordura Intra-Abdominal , Adulto , Masculino , Humanos , Feminino , Composição Corporal , Fatores de Risco Cardiometabólico , Escolaridade , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/prevenção & controle , Jejum , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como AssuntoRESUMO
PURPOSE OF REVIEW: The prevalence of obesity has exponentially increased during the past years. The assessment of human adipose tissue distribution enables the identification of diverse ectopic adipose tissue depots, and helps to explain its relationship with cardiovascular health status. In this review, we summarize the current methods used in the assessment of human adipose tissue distribution, and we discuss the relationship between ectopic adipose tissue distribution and the risk of developing cardiovascular diseases and metabolic complications. RECENT FINDINGS: The reference instruments to assess human adipose tissue distribution nowadays are the computed tomography and the magnetic resonance imaging (MRI). Today, MRI is the preferred imaging technique and enables the measurement of variations in the distribution of body adipose tissue among different phenotypes and individuals. This technique has helped to better understand the relationship between different ectopic adipose tissue depots and its relationship with cardiometabolic health among individuals. SUMMARY: Although body composition can be assessed by simple techniques, these calculations can provide erroneous results and conclusions, requiring complex interpretations when diverse metabolic situations are concomitantly engaged. Contrarily, medical imaging techniques (e.g. MRI) enables to objectively and unbiasedly measure changes that may occur during longitudinal studies (e.g. pharmacological drug interventions).
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Doenças Cardiovasculares , Humanos , Fatores de Risco , Doenças Cardiovasculares/etiologia , Tecido Adiposo/diagnóstico por imagem , Tecido Adiposo/metabolismo , Obesidade/complicações , Obesidade/diagnóstico por imagem , Obesidade/metabolismo , Imageamento por Ressonância Magnética/efeitos adversosRESUMO
OBJECTIVES: Fat depots localization has a critical role in the metabolic health status of adults. Nevertheless, whether that is also the case in children remains under-studied. Therefore, the aims of this study were: (i) to examine the differences between metabolically healthy (MHO) and unhealthy (MUO) overweight/obesity phenotypes on specific abdominal fat depots, and (ii) to further explore whether cardiorespiratory fitness plays a major role in the differences between metabolic phenotypes among children with overweight/obesity. METHODS: A total of 114 children with overweight/obesity (10.6 ± 1.1 years, 62 girls) were included. Children were classified as MHO (n = 68) or MUO. visceral (VAT), abdominal subcutaneous (ASAT), intermuscular abdominal (IMAAT), psoas, hepatic, pancreatic, and lumbar bone marrow adipose tissues were measured by magnetic resonance imaging. Cardiorespiratory fitness was assessed using the 20 m shuttle run test. RESULTS: MHO children had lower VAT and ASAT contents and psoas fat fraction compared to MUO children (difference = 12.4%-25.8%, all p < 0.035). MUO-unfit had more VAT and ASAT content than those MUO-fit and MHO-fit (difference = 34.8%-45.3%, all p < 0.044). MUO-unfit shows also greater IMAAT fat fraction than those MUO-fit and MHO-fit peers (difference = 16.4%-13.9% respectively, all p ≤ 0.001). In addition, MHO-unfit presented higher IMAAT fat fraction than MHO-fit (difference = 13.4%, p < 0.001). MUO-unfit presented higher psoas fat fraction than MHO-fit (difference = 29.1%, p = 0.008). CONCLUSIONS: VAT together with ASAT and psoas fat fraction, were lower in MHO than in MUO children. Further, we also observed that being fit, regardless of metabolic phenotype, has a protective role over the specific abdominal fat depots among children with overweight/obesity.
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Aptidão Cardiorrespiratória , Síndrome Metabólica , Humanos , Sobrepeso , Obesidade/metabolismo , Nível de Saúde , Gordura Abdominal/diagnóstico por imagem , Gordura Abdominal/metabolismo , Fenótipo , Síndrome Metabólica/metabolismo , Fatores de Risco , Índice de Massa CorporalRESUMO
OBJECTIVES: To examine the relationship between physical fitness and physical activity (PA) with specific abdominal fat depots and their potential implications for cardiometabolic risk and insulin resistance (IR) in children with overweight/obesity. MATERIALS AND METHODS: A total of 116 children with overweight/obesity (10.7 ± 1.1 year, 54% girls) participated in the study. Abdominal visceral (VAT), subcutaneous (ASAT), and intermuscular abdominal adipose tissue (IMAAT) were assessed by magnetic resonance imaging. The cardiometabolic risk (MetS) score and the insulin resistance homeostasis model assessment (HOMA-IR) were calculated. Health-related physical fitness components (treadmill test, and 20 m shuttle run, handgrip, standing broad jump and 4 × 10 m tests) were evaluated, and PA was measured (accelerometry). Children were categorized as fit or unfit for each specific fitness test, and as active or inactive. RESULTS: Higher VAT, ASAT, and IMAAT were associated with higher MetS score and HOMA-IR (all p < 0.02). A better performance in all fitness tests and total and vigorous PA were strongly associated with lower VAT (all p < 0.04), ASAT (all p < 0.005), and IMAAT (all p < 0.005). Fit or active children had lower VAT, ASAT, and IMAAT (all p < 0.03) than their unfit or inactive counterparts. CONCLUSION: These results reinforce the importance of having adequate fitness and PA levels to reduce abdominal fat accumulation in children. Given that VAT, ASAT, and IMAAT are associated with higher risk of developing cardiovascular diseases and type 2 diabetes, the improvement of physical fitness by the promotion of PA should be goals of lifestyle interventions for improving health in children with overweight/obesity.
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Diabetes Mellitus Tipo 2 , Sobrepeso , Gordura Abdominal , Criança , Exercício Físico , Feminino , Força da Mão , Humanos , Masculino , ObesidadeRESUMO
BACKGROUND: Falls represent important drivers of intrinsic capacity losses, functional limitations and reduced quality of life in the growing older adult's population, especially among those presenting with frailty. Despite exercise- and cognitive training-based interventions have shown effectiveness for reducing fall rates, evidence around their putative cumulative effects on falls and fall-related complications (such as fractures, reduced quality of life and functional limitations) in frail individuals remains scarce. The main aim of this study is to explore the effectiveness program combining an individualized exercise program and an executive function-based cognitive training (VIVIFRAIL-COGN) compared to usual care in the prevention of falls and fall-related outcomes over a 1-year follow-up. METHODS: This study is designed as a four-center randomized clinical trial with a 12-week intervention period and an additional 1-year follow-up. Three hundred twenty frail or pre-frail (≥ 1 criteria of the Frailty Phenotype) older adults (≥ 75 years) with high risk of falling (defined by fall history and gait performance) will be recruited in the Falls Units of the participating centers. They will be randomized in a 1:1 ratio to the intervention group (IG) or the control group (CG). The IG will participate in a home-based intervention combining the individualized Vivifrail multicomponent (aerobic, resistance, gait and balance and flexibility) exercise program and a personalized executive function-based cognitive training (VIVIFRAIL-COGN). The CG group will receive usual care delivered in the Falls Units, including the Otago Exercise Program. Primary outcome will be the incidence of falls (event rate/year) and will be ascertained by self-report during three visits (at baseline, and 6 and 12 weeks) and telephone-based contacts at 6, 9 and 12 months after randomization. Secondarily, effects on measures of physical and cognitive function, quality of life, nutritional, muscle quality and psychological status will be evaluated. DISCUSSION: This trial will provide new evidence about the effectiveness of an individualized multidomain intervention by studying the effect of additive effects of cognitive training and physical exercise to prevent falls in older frail persons with high risk of falling. Compared to usual care, the combined intervention is expected to show additive effects in the reduction of the incidence of falls and associated adverse outcomes. TRIAL REGISTRATION: NCT04911179 02/06/2021.
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Fragilidade , Idoso , Cognição/fisiologia , Exercício Físico/fisiologia , Terapia por Exercício/métodos , Idoso Fragilizado/psicologia , Humanos , Estudos Multicêntricos como Assunto , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
The effects of exercise on the core musculature have not been investigated in prepubescents. The main purpose of the present study was to determine the volume and degree of asymmetry of rectus abdominis, obliques and transversus abdominis, quadratus lumborum, iliopsoas, gluteus and paravertebralis muscles in prepubescent tennis players and in untrained boys. The muscle volume was determined using magnetic resonance imaging (MRI) in 7 male prepubescent tennis players and 10 untrained controls (mean age 11.0 ± 0.8 years, Tanner 1-2). After accounting for height and body weight as covariates, the tennis players had 14-34% greater volume than the controls in all the muscles analysed (P < 0.05) except in paravertebralis, dominant quadratus lumborum and non-dominant gluteus, which had similar volumes in both groups (P = NS). Compared to controls, the tennis players displayed a greater degree of asymmetry in quadratus lumborum and rectus abdominis (3% vs. 15%, P < 0.01 and 8% vs. 17%, P = 0.06, respectively). The level of asymmetry of obliques and transversus abdominis, iliopsoas, gluteus and paravertebralis muscles was similar in both groups (P = NS). In conclusion, tennis playing at prepubertal ages induces a selective hypertrophy of the core musculature and exaggerates the degree of asymmetry of quadratus lumborum and rectus abdominis compared to untrained boys.
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Músculos Abdominais/anatomia & histologia , Músculos Abdominais/diagnóstico por imagem , Condicionamento Físico Humano , Tênis/fisiologia , Estatura , Peso Corporal , Criança , Humanos , Imageamento por Ressonância Magnética , MasculinoRESUMO
CONTEXT: The muscular function restoration related to the type of physical rehabilitation followed after anterior cruciate ligament reconstruction (ACLR) using autologous hamstring tendon graft in terms of strength and cross-sectional area (CSA) remain controversial. OBJECTIVE: To analyze the CSA and force output of quadriceps and hamstring muscles in subjects following either an Objective Criteria-Based Rehabilitation (OCBR) algorithm or the usual care (UCR) for ACL rehabilitation in Spain, before and 1 year after undergoing an ACLR. DESIGN: Longitudinal clinical double-blinded randomized controlled trial. SETTING: Sports-medicine research center. PATIENTS: 40 recreational athletes (30 male, 10 female [24 ± 6.9 y, 176.55 ± 6.6 cm, 73.58 ± 12.3 kg]). INTERVENTION: Both groups conducted differentiated rehabilitation procedures after ACLR. Those belonging to OCBR group were guided in their recovery according to the current evidence-based principles. UCR group followed the national conventional approach for ACL rehabilitation. MAIN OUTCOME MEASURES: Concentric isokinetic knee joint flexor-extension torque assessments at 180°/s and Magnetic Resonance Imaging (MRI) evaluations were performed before and 12 months after ACLR. Anatomical muscle CSA (mm2) was assessed, in Quadriceps, Biceps femoris, Semitendinous, Semimembranosus, and Gracilis muscles at 50% and 70% femur length. RESULTS: Reduced muscle CSA was observed in both treatment groups for Semitendinosus and Gracilis 1 year after ACLR. At 1-year follow-up, subjects allocated to the OCBR demonstrated greater knee flexor and extensor peak torque values in their reconstructed limbs in comparison with patients treated by UCR. CONCLUSIONS: Objective atrophy of Semitendinosus and Gracilis muscles related to surgical ACLR was found to persist in both rehabilitation groups. However, OCBR after ACLR lead to substantial gains on maximal knee flexor strength and ensured more symmetrical anterior-posterior laxity levels at the knee joint.
Assuntos
Lesões do Ligamento Cruzado Anterior/reabilitação , Reconstrução do Ligamento Cruzado Anterior , Traumatismos em Atletas/reabilitação , Adolescente , Adulto , Lesões do Ligamento Cruzado Anterior/cirurgia , Traumatismos em Atletas/cirurgia , Método Duplo-Cego , Feminino , Músculos Isquiossurais/fisiologia , Tendões dos Músculos Isquiotibiais/transplante , Humanos , Articulação do Joelho , Estudos Longitudinais , Masculino , Força Muscular , Músculo Quadríceps/fisiologia , Amplitude de Movimento Articular , Coxa da Perna/diagnóstico por imagem , Torque , Adulto JovemRESUMO
OBJECTIVE: to compare the different adipose tissue (AT) compartments, muscle mass, muscle fat infiltration, coronary calcium, as well as associations among changes in different AT compartments between frail and robust nonagenarians. MATERIALS AND METHODS: Forty-two elderly subjects took part in this study: 29 institutionalized frail elderly (92.0 ± 8 years) and 13 robust elderly (88.2 ± 4.1 years). All patients underwent helical thoracic, abdominal and thigh computed tomography (CT). In addition, a non-enhanced prospectively ECG-triggered cardiac CT was performed to quantify the amount of coronary artery calcification and measure pericardial AT. RESULTS: The robust group presented significantly greater pericardial and abdominal AT volume, as well as greater axial and appendicular muscle size and high-density muscle tissue (greater muscle quality) than the frail group (P < 0.001), whereas no differences between groups were observed in coronary calcium. There were positive correlations between pericardial AT with visceral and subcutaneous AT values, as well as between pericardial AT and quadriceps, hamstrings, psoas and paravertebral low-density muscle tissues in the frail and robust groups (r = 0.57 to 0.91,P < 0.05). CONCLUSIONS: Robust group presented greater muscle size and quality in the axial and appendicular muscles, as well as pericardial and abdominal AT area than the frail group. KEY POINTS: ⢠Robust nonagenarians presented more pericardial and abdominal AT volume than frail. ⢠Frailty is associated with lower muscle size and high-density muscle tissue. ⢠Muscle-fat infiltration shares analogous pattern of visceral and pericardial AT distribution.
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Tecido Adiposo/patologia , Doença da Artéria Coronariana/patologia , Idoso Fragilizado , Doenças Musculares/patologia , Calcificação Vascular/patologia , Gordura Abdominal/diagnóstico por imagem , Gordura Abdominal/patologia , Tecido Adiposo/diagnóstico por imagem , Idoso , Doença da Artéria Coronariana/diagnóstico por imagem , Estudos Transversais , Feminino , Coração/diagnóstico por imagem , Humanos , Institucionalização , Masculino , Músculo Esquelético/patologia , Doenças Musculares/diagnóstico por imagem , Pericárdio/diagnóstico por imagem , Estudos Retrospectivos , Coxa da Perna , Tomografia Computadorizada por Raios X , Calcificação Vascular/diagnóstico por imagemRESUMO
CONTEXT: Exercise reduces adiposity, but its influence on bone marrow fat fraction (BMFF) is unknown; nor is it known whether a reduction in liver fat content mediates this reduction. OBJECTIVES: (i) To determine whether incorporating exercise into a lifestyle program reduces the lumbar spine (LS)-BMFF, and (ii), to investigate whether changes in liver fat mediate any such effect. DESIGN: Ancillary analysis of a two-arm, parallel, non-randomized clinical trial. SETTING: Primary care centres in Vitoria-Gasteiz (Spain). PARTICIPANTS: A total of 116 children with overweight/obesity were assigned to a 22-week family-based lifestyle program (control group [n=57]) or the same program plus an exercise intervention (exercise group [n=59]. INTERVENTIONS: The compared interventions consisted of a family-based lifestyle program (two 90-minute sessions/month) and the same program plus supervised exercise (three 90-minute sessions/week). MAIN OUTCOMES AND MEASURES: The primary outcome examined was the change in LS-BMFF between baseline and 22 weeks, as estimated by MRI. The effect of changes in hepatic fat on LS-BMFF were also recorded. RESULTS: Mean weight loss difference between groups was 1.4±0.5 kg favour of the exercise group. Only the children in the exercise group experienced a reduction in LS-BMFF (effect size [Cohen d] -0.42, CI: -0.86, -0.01). Importantly, 40.9% of the reductions in LS-BMFF were mediated by changes in percentage hepatic fat (indirect effect: ß=-0.104, 95%CI=-0.213, -0.019). The impact of changes in hepatic fat on LS-BMFF was independent of weight loss. CONCLUSIONS AND RELEVANCE: The addition of exercise to a family-based lifestyle program designed to reduce cardiometabolic risk improves bone health by reducing LS-BMFF in children with overweight or obesity. This beneficial effect on bone marrow appears to be mediated by reductions in liver fat.
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Quadriceps muscle strains frequently occur in sports that require repetitive kicking and sprinting, and are common in football in its different forms around the world. This paper is a review of aetiology, mechanism of injury and the natural history of rectus femoris injury. Investigating the mechanism and risk factors for rectus femoris muscle injury aims to allow the development of a framework for future initiatives to prevent quadriceps injury in football players.
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Músculo Quadríceps/lesões , Futebol/lesões , Fatores Etários , Traumatismos em Atletas/etiologia , Traumatismos em Atletas/patologia , Traumatismos em Atletas/prevenção & controle , Estatura/fisiologia , Peso Corporal/fisiologia , Lateralidade Funcional/fisiologia , Humanos , Traumatismos da Perna/etiologia , Traumatismos da Perna/patologia , Traumatismos da Perna/prevenção & controle , Imageamento por Ressonância Magnética , Força Muscular/fisiologia , Exercícios de Alongamento Muscular , Maleabilidade/fisiologia , Músculo Quadríceps/patologia , Fatores de Risco , Corrida/lesões , Traumatismos dos Tendões/etiologia , Traumatismos dos Tendões/patologia , Traumatismos dos Tendões/prevenção & controleRESUMO
The aim of this study was to investigate the effects of the Nordic hamstring exercise on the biceps femoris long head (BFlh), biceps femoris short head (BFsh), semitendinosus (SMT), and semimembranosus (SMM) muscles. The Nordic hamstring strengthening exercise has been widely used in injury prevention, yet not much is known about the site-specific activation of this exercise on different muscles of the thigh. Eight male national-level referees were assigned to a Nordic hamstring exercise protocol (5 sets of 8 repetitions). Magnetic resonance imaging (MRI) of the subjects' thighs was performed before, within 3 minutes after, and repeated again 72 hours after the exercise intervention. Fifteen axial scans of the thigh interspaced by a distance of 1 of 15 right femur length were obtained from the level of 1 of 15 Lf to 15 of 15 Lf. The MRI data were analyzed for signal intensity changes. After 72 hours, significant changes in transverse (spin-spin) relaxation time signal intensity and cross-sectional area were maintained distally at BFsh cranial portion and concretely at the nondominant limb, whereas no significant changes were observed in transverse (spin-spin) relaxation time signal intensity at BFlh, SMM, or SMT. This study demonstrated that the Nordic hamstring exercise did not result in a uniform response (training stimulus) neither interhamstring (dominant vs. nondominant) nor intrahamstring muscles (same leg) and was better suited for loading proximal BFsh.
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Exercício Físico/fisiologia , Imageamento por Ressonância Magnética , Força Muscular/fisiologia , Músculo Esquelético/patologia , Músculo Esquelético/fisiologia , Coxa da Perna/patologia , Coxa da Perna/fisiologia , Adulto , Análise de Variância , Traumatismos em Atletas/prevenção & controle , Humanos , Masculino , Contração Muscular/fisiologia , Músculo Esquelético/lesões , Coxa da Perna/lesõesRESUMO
Although many different hamstring strengthening exercises exist, the effect on site specific activation of these exercises on different muscles of the leg is unclear. This study investigated the effects of the eccentric leg curl (LC) and lunge (L) exercises on the biceps femoris long head (BFl), biceps femoris short head (BFs), semitendinosus (ST), semimembranosus (SM), and adductor magnus (AM). Each leg of 11 male professional soccer players was randomly assigned to an LC or L exercise protocol (3 sets of 6 repetitions). Functional magnetic resonance imaging (fMRI) of the subjects' thighs were performed before and 48 hours after the intervention. Fifteen axial scans of the thigh interspaced by a distance of 1/15 right femur length (Lf) were obtained. The fMRI data were analyzed for signal intensity changes. No significant changes were observed in absolute short tau inversion recovery values for the SM and BFs. Significant changes for the ST (â¼21-45%) from sections 4 to 10, AM (â¼2-13%) at section 4, and BFl (â¼ -3 vs. 8%) at section 7 were noted. LC exercises load all the regions of the ST muscle. The L exercises load the proximal regions of the BFl and AM. These findings may have relevance when designing protocols for prevention and rehabilitation of hamstring injuries.
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Exercício Físico/fisiologia , Extremidade Inferior/fisiologia , Imageamento por Ressonância Magnética , Força Muscular/fisiologia , Músculo Esquelético/anatomia & histologia , Humanos , Masculino , Músculo Esquelético/fisiologia , Futebol/fisiologia , Adulto JovemRESUMO
The aim was to determine the volume and degree of asymmetry of quadratus lumborum (QL), obliques, and transversus abdominis; the last two considered conjointly (OT), in tennis and soccer players. The volume of QL and OT was determined using magnetic resonance imaging in professional tennis and soccer players, and in non-active controls (n = 8, 14, and 6, respectively). In tennis players the hypertrophy of OT was limited to proximal segments (cephalic segments), while in soccer players it was similar along longitudinal axis. In tennis players the hypertrophy was asymmetric (18% greater volume in the non-dominant than in the dominant OT, p = 0.001), while in soccer players and controls both sides had similar volumes (p > 0.05). In controls, the non-dominant QL was 15% greater than that of the dominant (p = 0.049). Tennis and soccer players had similar volumes in both sides of QL. Tennis alters the dominant-to-non-dominant balance in the muscle volume of the lateral abdominal wall. In tennis the hypertrophy is limited to proximal segments and is greater in the non-dominant side. Soccer, however, is associated to a symmetric hypertrophy of the lateral abdominal wall. Tennis and soccer elicit an asymmetric hypertrophy of QL.
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Músculos Abdominais/patologia , Imageamento por Ressonância Magnética , Músculo Esquelético/patologia , Futebol/fisiologia , Tênis/fisiologia , Adulto , Estudos de Casos e Controles , Humanos , Hipertrofia , Masculino , Adulto JovemRESUMO
This study examines both the effect of a twice-weekly combined exercise-1 h session of strength and 1 h session of impact-aerobic-on body composition and dietary habits after one year of treatment with aromatase inhibitors (AI) in breast cancer survivors. Overall, forty-three postmenopausal women with a BMI ≤ 35 kg/m2, breast cancer survivors treated with AI, were randomized into two groups: a control group (CG) (n = 22) and a training group (IG) (n = 21). Body composition, i.e., abdominal, visceral, and subcutaneous adipose tissue) was measured by magnetic resonance. In addition, some questionnaires were used to gather dietary data and to measure adherence to the Mediterranean diet. After one year, women in the IG showed a significant improvement in body composition, indicated by decreases in subcutaneous and visceral adipose tissue, and total fat tissue. Furthermore, the dietary habits were compatible with moderate adherence to the Mediterranean diet pattern and a low dietary intake of Ca, Zn, Folic Ac, and vitamins D, A, and E. A twice-weekly training program combining impact aerobic exercise and resistance exercise may be effective in improving the body composition for postmenopausal women who have breast cancer treated with AI, and the results suggest the need for nutritional counselling for this population.
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Neoplasias da Mama , Sobreviventes de Câncer , Feminino , Humanos , Neoplasias da Mama/terapia , Inibidores da Aromatase/uso terapêutico , Exercício Físico , Composição Corporal , Comportamento AlimentarRESUMO
CONTEXT: Hepatic steatosis is associated with decreased bone mineral density (BMD). Bone marrow fat fraction (BMFF) could play a role in this relationship in children with obesity. OBJECTIVE: The objectives of this work were (i) to examine the relationship between the lumbar spine (LS) BMFF and BMD, and (ii) to explore the mediating role of LS-BMFF on the relationship between percentage hepatic fat with LS-BMD in preadolescent children with overweight/obesity. METHODS: Hepatic fat and LS-BMFF (magnetic resonance imaging) and areal LS-BMD (LS-aBMD, dual-energy x-ray absorptiometry) were measured in 106 children (aged 10.6 ± 1.1 years, 53.8% girls) with overweight/obesity. RESULTS: LS-BMFF was inversely associated with LS-aBMD (r = -0.313; P = .001) and directly related with percentage hepatic fat (r = 0.276; P = .005). LS-BMFF was significantly greater in children with than without hepatic steatosis (P = .003; Cohen's d: 0.61; 95% CI, -0.21 to 1.0), while no significant difference was seen between children with overweight and those with obesity (P = .604; Cohen's d: 0.16; 95% CI, -0.21-0.55). Mediating analysis indicated that LS-BMFF is an important mediator (50%) in the association of hepatic fat with lower LS-aBMD (indirect effect: ß = -.076; 95% CI, -0.143 to -0.015). CONCLUSION: These findings suggest that hepatic steatosis, rather than overall excess adiposity, is associated with greater bone marrow adipose tissue in preadolescent children with overweight/obesity, which in turn, is related to lower BMD. Hepatic steatosis could be a potential biomarker of osteoporosis risk, and a therapeutic target for interventions that aim to reduce not only hepatic steatosis, but for those designed to improve bone health in such children.
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Densidade Óssea , Fígado Gorduroso , Feminino , Criança , Humanos , Masculino , Sobrepeso/complicações , Sobrepeso/patologia , Medula Óssea/diagnóstico por imagem , Medula Óssea/patologia , Obesidade/patologia , Tecido Adiposo/diagnóstico por imagem , Tecido Adiposo/patologia , Absorciometria de Fóton , Fígado Gorduroso/diagnóstico por imagem , Fígado Gorduroso/patologia , Vértebras LombaresRESUMO
BACKGROUND/AIMS: A weight-loss diet alone or combined with a progressive resistance training program induced different adaptations on cardiometabolic risk, i.e. regional changes in visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) volume distribution patterns. We hypothesized that a heterogeneous adipose tissue metabolism may exist between visceral fat at different discal levels. METHODS: Thirty-four obese women, aged 40-60 years, were randomized to three groups: a control group (n = 9), a diet group (WL; n = 12) with a caloric restriction of 500 kcal/day during 16 weeks, or a diet-plus-resistance-training group (WL+RT; n = 13) with the same caloric restriction and a 16-week resistance training of 2 sessions per week. RESULTS: The association pattern between abdominal fat depots and glucose metabolism variables showed a change from the L4-L5 region (preintervention) to VAT L2-L3 and SAT L2-L3 in the WL and WL+RT groups, respectively. It is noteworthy that accumulation of fat in the midthigh was not characterized by a more favorable lipid profile or glucose metabolism. CONCLUSION: Our results reinforce the importance of considering L2-L3 images to predict insulin resistance after a weight-loss diet, alone or combined with resistance training.
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Restrição Calórica , Doenças Cardiovasculares/dietoterapia , Dieta Redutora , Gordura Intra-Abdominal/metabolismo , Treinamento Resistido/métodos , Adulto , Biomarcadores/sangue , Índice de Massa Corporal , HDL-Colesterol , LDL-Colesterol , Ingestão de Energia/fisiologia , Metabolismo Energético/fisiologia , Feminino , Humanos , Insulina/sangue , Resistência à Insulina , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Obesidade/dietoterapia , Fatores de Risco , Gordura Subcutânea/metabolismoRESUMO
OBJECTIVE: To assess rectus abdominis (RA) thickness and injury prevalence using ultrasound in a group of professional tennis players. Observations with regard to muscle fiber repair is described. We likewise studied the potential link between RA volume asymmetry and the risk of muscle strain. MATERIALS AND METHODS: The degree of asymmetry between the different RA slices was assessed using ultrasound in 61 professional tennis players. The history of RA injury in these tennis players was likewise studied, taking into account the following factors: dominant vs non-dominant arm, history of RA strains, duration thereof and number of recurrences. Ultrasound examination was performed with an 8- to 12-MHz linear multi-frequency transducer. RESULTS: Ultrasound revealed the presence of fibrous scar tissue in the RA muscle in 18 cases (29.5%). In all instances, the lesion was located in the RA on the side of the nondominant arm. In 16 of the cases, the lesion was infra-umbilical and L2 was affected in two cases. The mean maximum width of the fibrous repair tissue was 9 mm (range 5-16). The mean distance between the umbilicus and the scar was 5.8 cm (range 2.9-11.4). Statistical study of the ultrasound measurements obtained for the different slices revealed statistically significant differences between the different depths and according to arm dominance. CONCLUSIONS: In the series studied, the prevalence of RA muscle lesion in professional tennis players was 29.5%. Asymmetric hypertrophy of the RA muscle appears to constitute a risk factor for suffering an injury in this location.
Assuntos
Reto do Abdome/lesões , Reto do Abdome/patologia , Tênis/lesões , Tênis/estatística & dados numéricos , Ultrassonografia/estatística & dados numéricos , Comorbidade , Feminino , Humanos , Hipertrofia/diagnóstico por imagem , Hipertrofia/epidemiologia , Masculino , Prevalência , Reto do Abdome/diagnóstico por imagem , Fatores de Risco , Espanha/epidemiologia , Adulto JovemRESUMO
Importance: Excess abdominal fat is a major determinant in the development of insulin resistance and other metabolic disorders. Increased visceral adipose tissue (VAT) seems to precede the development of insulin resistance and is therefore a prime target of childhood lifestyle interventions aimed at preventing diabetes. Objectives: To examine the effect of added exercise to a family-based lifestyle intervention program designed to reduce VAT plus subcutaneous (ASAT), intermuscular (IMAAT), and pancreatic (PAT) adipose tissue in children with overweight or obesity and to explore the effect of changes in VAT on insulin resistance. Design, Setting, and Participants: This 2-group, parallel-design clinical trial was conducted in Vitoria-Gasteiz, Spain. A total of 116 children with overweight or obesity participated and were assigned to a 22-week family-based lifestyle program (control group [n = 57]) or the same program plus an exercise intervention (exercise group [n = 59]). Data were collected between September 1, 2014, and June 30, 2017, and imaging processing for fat depot assessments and data analysis were performed between May 1, 2019, and February 12, 2021. Interventions: The compared interventions consisted of a family-based lifestyle and psychoeducation program (two 90-minute sessions per month) and the same program plus supervised exercise (three 90-minute sessions per week). Main Outcomes and Measures: The primary outcome of this study was the change in VAT between baseline and 22 weeks as estimated by magnetic resonance imaging. The secondary outcomes were changes in ASAT, IMAAT, and PAT. The effect of changes in VAT area on insulin resistance was also recorded. Results: The 116 participants included in the analysis (62 girls [53.4%]) had a mean (SD) age of 10.6 (1.1) years, and 67 (57.8%) presented with obesity. Significantly greater reductions were recorded for the exercise group in terms of reduction in VAT (-18.1% vs -8.5% for the control group; P = .004), ASAT (-9.9% vs -3.0%; P = .001), and IMAAT (-6.0% vs -2.6%; P = .02) fat fractions compared with the control group. Changes in VAT explained 87.6% of the improvement seen in insulin resistance (ß = -0.102 [95% CI, -0.230 to -0.002]). Conclusions and Relevance: These findings suggest that the addition of exercise to a lifestyle intervention program substantially enhanced the positive effects on abdominal fat depots in children with overweight or obesity. In addition, the reduction in VAT seemed to largely mediate the improvement of insulin sensitivity. These results highlight the importance of including exercise as part of lifestyle therapies aimed at treating childhood obesity and preventing the development of type 2 diabetes. Trial Registration: ClinicalTrials.gov Identifier: NCT02258126.