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1.
Sensors (Basel) ; 23(4)2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36850844

RESUMO

The purpose of this study was to develop peak ground reaction force (pGRF) and peak loading rate (pLR) prediction equations for high-impact activities in adult subjects with a broad range of body masses, from normal weight to severe obesity. A total of 78 participants (27 males; 82.4 ± 20.6 kg) completed a series of trials involving jumps of different types and heights on force plates while wearing accelerometers at the ankle, lower back, and hip. Regression equations were developed to predict pGRF and pLR from accelerometry data. Leave-one-out cross-validation was used to calculate prediction accuracy and Bland-Altman plots. Body mass was a predictor in all models, along with peak acceleration in the pGRF models and peak acceleration rate in the pLR models. The equations to predict pGRF had a coefficient of determination (R2) of at least 0.83, and a mean absolute percentage error (MAPE) below 14.5%, while the R2 for the pLR prediction equations was at least 0.87 and the highest MAPE was 24.7%. Jumping pGRF can be accurately predicted through accelerometry data, enabling the continuous assessment of mechanical loading in clinical settings. The pLR prediction equations yielded a lower accuracy when compared to the pGRF equations.


Assuntos
Aceleração , Acelerometria , Adulto , Masculino , Humanos , Articulação do Tornozelo , Dorso , Projetos de Pesquisa
2.
Curr Osteoporos Rep ; 20(6): 453-468, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36401774

RESUMO

PURPOSE OF REVIEW: To revisit the bone tissue mechanotransduction mechanisms behind the bone tissue response to mechanical loading and, within this context, explore the possible negative influence of regular swimming practice on bone health, particularly during the growth and development period. RECENT FINDINGS: Bone is a dynamic tissue, responsive to mechanical loading and unloading, being these adaptative responses more intense during the growth and development period. Cross-sectional studies usually report a lower bone mass in swimmers compared to athletes engaged in weigh-bearing sports. However, studies with animal models show contradictory findings about the effect of swimming on bone health, highlighting the need for longitudinal studies. Due to its microgravity characteristics, swimming seems to impair bone mass, but mostly at the lower limbs. It is unkown if there is a causal relationship between swimming and low BMD or if other confounding factors, such as a natural selection whithin the sport, are the cause.


Assuntos
Densidade Óssea , Natação , Animais , Estudos Transversais , Mecanotransdução Celular , Desenvolvimento Ósseo , Osso e Ossos
3.
Int J Sports Med ; 43(9): 818-824, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35419778

RESUMO

Patients who undergo bariatric surgery (BS) have an increased risk of falls. Our aim was to determine if a multicomponent exercise intervention after BS improves balance. Eighty-four patients with obesity enrolled for BS were recruited and 1 month after BS randomly allocated to a control (CG; standard medical care) or exercise group (EG; exercise plus standard medical care) consisting of a supervised multicomponent training program (3d/week; 75 min/session; 5 months). Anthropometry, lower limb muscle strength (isokinetic dynamometer), vitamin D (ELISA) and balance in bipedal stance (force platform) were assessed pre-BS, 1 month and 6 months post-BS. One month post-BS, significant balance improvements were observed, namely in antero-posterior center of gravity (CoG) displacement and velocity, and medio-lateral and total CoG velocity. Between 1- and 6-months post-BS, improvements in balance were observed only in the EG, with a significant treatment effect on CoG displacement area and antero-posterior CoG displacement. No significant differences were observed between EG and CG over time in any of the anthropometric, muscle strength, and vitamin D variables assayed. In conclusion, a multicomponent exercise intervention program improves some balance parameters in patients with severe obesity following BS and therefore should be part of post-BS follow-up care as a potential strategy to reduce falls and associated injuries.


Assuntos
Cirurgia Bariátrica , Exercício Físico , Acidentes por Quedas/prevenção & controle , Exercício Físico/fisiologia , Terapia por Exercício , Humanos , Força Muscular/fisiologia , Equilíbrio Postural/fisiologia , Vitamina D
4.
Sensors (Basel) ; 21(8)2021 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-33917654

RESUMO

Multisite neural probes are a fundamental tool to study brain function. Hybrid silicon/polymer neural probes combine rigid silicon and flexible polymer parts into one single device and allow, for example, the precise integration of complex probe geometries, such as multishank designs, with flexible biocompatible cabling. Despite these advantages and benefiting from highly reproducible fabrication methods on both silicon and polymer substrates, they have not been widely available. This paper presents the development, fabrication, characterization, and in vivo electrophysiological assessment of a hybrid multisite multishank silicon probe with a monolithically integrated polyimide flexible interconnect cable. The fabrication process was optimized at wafer level, and several neural probes with 64 gold electrode sites equally distributed along 8 shanks with an integrated 8 µm thick highly flexible polyimide interconnect cable were produced. The monolithic integration of the polyimide cable in the same fabrication process removed the necessity of the postfabrication bonding of the cable to the probe. This is the highest electrode site density and thinnest flexible cable ever reported for a hybrid silicon/polymer probe. Additionally, to avoid the time-consuming bonding of the probe to definitive packaging, the flexible cable was designed to terminate in a connector pad that can mate with commercial zero-insertion force (ZIF) connectors for electronics interfacing. This allows great experimental flexibility because interchangeable packaging can be used according to experimental demands. High-density distributed in vivo electrophysiological recordings were obtained from the hybrid neural probes with low intrinsic noise and high signal-to-noise ratio (SNR).


Assuntos
Polímeros , Silício , Eletrodos , Fenômenos Eletrofisiológicos
5.
Opt Express ; 28(22): 32302-32315, 2020 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-33114919

RESUMO

This work reports on high extraction efficiency in subwavelength GaAs/AlGaAs semiconductor nanopillars. We achieve up to 37-fold enhancement of the photoluminescence (PL) intensity from sub-micrometer (sub-µm) pillars without requiring back reflectors, high-Q dielectric cavities, nor large 2D arrays or plasmonic effects. This is a result of a large extraction efficiency for nanopillars <500 nm width, estimated in the range of 33-57%, which is much larger than the typical low efficiency (∼2%) of micrometer pillars limited by total internal reflection. Time-resolved PL measurements allow us to estimate the nonradiative surface recombination of fabricated pillars. We conclusively show that vertical-emitting nanopillar-based LEDs, in the best case scenario of both reduced surface recombination and efficient light out-coupling, have the potential to achieve notable large external quantum efficiency (∼45%), whereas the efficiency of large µm-pillar planar LEDs, without further methods, saturates at ∼2%. These results offer a versatile method of light management in nanostructures with prospects to improve the performance of optoelectronic devices including nanoscale LEDs, nanolasers, single photon sources, photodetectors, and solar cells.

6.
J Physiol ; 593(17): 3885-97, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26010517

RESUMO

The present study aimed to test whether a chronic intermittent workload could induce an adaptive cardiac phenotype Chronic intermittent workload induced features of adaptive hypertrophy This was paralleled by protection against acute pressure overload insult The heart may adapt favourably to balanced demands, regardless of the nature of the stimuli. The present study aimed to test whether submitting the healthy heart to intermittent and tolerable amounts of workload, independently of its nature, could result in an adaptive cardiac phenotype. Male Wistar rats were subjected to treadmill running (Ex) (n = 20), intermittent cardiac overload with dobutamine (ITO) (2 mg kg(-1) , s.c.; n = 20) or placebo administration (Cont) (n = 20) for 5 days week(-1) for 8 weeks. Animals were then killed for histological and biochemical analysis or subjected to left ventricular haemodynamic evaluation under baseline conditions, in response to isovolumetric contractions and to sustained LV acute pressure overload (35% increase in peak systolic pressure maintained for 2 h). Baseline cardiac function was enhanced only in Ex, whereas the response to isovolumetric heartbeats was improved in both ITO and Ex. By contrast to the Cont group, in which rats developed diastolic dysfunction with sustained acute pressure overload, ITO and Ex showed increased tolerance to this stress test. Both ITO and Ex developed cardiomyocyte hypertrophy without fibrosis, no overexpression of osteopontin-1 or ß-myosin heavy chain, and increased expression of sarcoplasmic reticulum Ca(2+) protein. Regarding hypertrophic pathways, ITO and Ex showed activation of the protein kinase B/mammalian target of rapamycin pathway but not calcineurin. Mitochondrial complex IV and V activities were also increased in ITO and Ex. Chronic submission to controlled intermittent cardiac overload, independently of its nature, results in an adaptive cardiac phenotype. Features of the cardiac overload, such as the duration and magnitude of the stimuli, may play a role in the development of an adaptive or maladaptive phenotype.


Assuntos
Adaptação Fisiológica , Cardiomegalia , Animais , Pressão Sanguínea , Cardiomegalia/patologia , Cardiomegalia/fisiopatologia , Cardiotônicos/farmacologia , Dobutamina/farmacologia , Coração/fisiologia , Masculino , Mitocôndrias Cardíacas/fisiologia , Miocárdio/patologia , Tamanho do Órgão , Fenótipo , Condicionamento Físico Animal/fisiologia , Ratos Wistar , Corrida/fisiologia
7.
Basic Res Cardiol ; 110(6): 57, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26463598

RESUMO

Clinical studies suggest that aerobic exercise can exert beneficial effects in pulmonary arterial hypertension (PAH), but the underlying mechanisms are largely unknown. We compared the impact of early or late aerobic exercise training on right ventricular function, remodeling and survival in experimental PAH. Male Wistar rats were submitted to normal cage activity (SED), exercise training in early (EarlyEX) and in late stage (LateEX) of PAH induced by monocrotaline (MCT, 60 mg/kg). Both exercise interventions resulted in improved cardiac function despite persistent right pressure-overload, increased exercise tolerance and survival, with greater benefits in EarlyEX+MCT. This was accompanied by improvements in the markers of cardiac remodeling (SERCA2a), neurohumoral activation (lower endothelin-1, brain natriuretic peptide and preserved vascular endothelial growth factor mRNA), metabolism and mitochondrial oxidative stress in both exercise interventions. EarlyEX+MCT provided additional improvements in fibrosis, tumor necrosis factor-alpha/interleukin-10 and brain natriuretic peptide mRNA, and beta/alpha myosin heavy chain protein expression. The present study demonstrates important cardioprotective effects of aerobic exercise in experimental PAH, with greater benefits obtained when exercise training is initiated at an early stage of the disease.


Assuntos
Hipertensão Pulmonar/terapia , Condicionamento Físico Animal , Função Ventricular Direita , Remodelação Ventricular , Animais , Biomarcadores/sangue , Tolerância ao Exercício , Hipertensão Pulmonar/induzido quimicamente , Hipertensão Pulmonar/metabolismo , Hipertensão Pulmonar/fisiopatologia , Masculino , Monocrotalina , Distribuição Aleatória , Ratos Wistar
8.
J Bone Miner Metab ; 33(6): 605-14, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25298329

RESUMO

Findings on experimental animals show that ovarian failure is accompanied by a decrease in motor activity. As mechanical loading has a vital role in the maintenance of skeletal health, our aim was to determine to what extent this decrease in motor activity contributes to ovariectomy-induced bone loss. Thirty-two female Wistar rats were ovariectomized or sham-operated and housed in standard cages or with access to running wheels for 36 weeks with their running distance monitored. Markers of bone turnover were assayed in the serum, and bone geometry, trabecular and cortical bone microarchitecture, mineralization degree, and biomechanical properties were assessed in the femur. Differences between groups were determined by one-way ANOVA. Although reduced motor activity and sex steroid deficiency both resulted in decreases in trabecular bone volume, trabecular number decreases were mostly associated with sex steroid deficiency, whereas trabecular thickness decreases were mostly associated with sedentary behavior. Cortical bone appeared to be more sensitive to variations in motor activity, whereas bone turnover rate and bone tissue mineralization degree seemed to be primarily affected by sex steroid deficiency, even though they were further aggravated by sedentary behavior. Increases in femur length were mostly a consequence of sex steroid deficiency, whereas femoral neck length was also influenced by sedentary behavior. Differences in mechanical properties resulted mostly from differences in physical activity. Both the direct effect of sex steroid deficiency and the indirect effect of motor activity changes are implicated in bone loss following ovariectomy.


Assuntos
Osso e Ossos/patologia , Estrogênios/deficiência , Atividade Motora , Insuficiência Ovariana Primária/patologia , Animais , Biomarcadores/metabolismo , Fenômenos Biomecânicos , Peso Corporal , Densidade Óssea , Remodelação Óssea , Osso e Ossos/fisiopatologia , Feminino , Fêmur/diagnóstico por imagem , Fêmur/patologia , Tamanho do Órgão , Insuficiência Ovariana Primária/fisiopatologia , Radiografia , Ratos Wistar
9.
Sports Med ; 54(8): 2071-2095, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38717713

RESUMO

BACKGROUND: Polarized training intensity distribution (POL) was recently suggested to be superior to other training intensity distribution (TID) regimens for endurance performance improvement. OBJECTIVE: We aimed to systematically review and meta-analyze evidence comparing POL to other TIDs on endurance performance. METHODS: PRISMA guidelines were followed. The protocol was registered at PROSPERO (CRD42022365117). PubMed, Scopus, and Web of Science were searched up to 20 October 2022 for studies in adults and young adults for ≥ 4 weeks comparing POL with other TID interventions regarding VO2peak, time-trial (TT), time to exhaustion (TTE) or speed or power at the second ventilatory or lactate threshold (V/P at VT2/LT2). Risk of bias was assessed with RoB-2 and ROBINS-I. Certainty of evidence was assessed with GRADE. Results were analyzed by random effects meta-analysis using standardized mean differences. RESULTS: Seventeen studies met the inclusion criteria (n = 437 subjects). Pooled effect estimates suggest POL superiority for improving VO2peak (SMD = 0.24 [95% CI 0.01, 0.48]; z = 2.02 (p = 0.040); 11 studies, n = 284; I2 = 0%; high certainty of evidence). Superiority, however, only occurred in shorter interventions (< 12 weeks) (SMD = 0.40 [95% CI 0.08, 0.71; z = 2.49 (p = 0.01); n = 163; I2 = 0%) and for highly trained athletes (SMD = 0.46 [95% CI 0.10, 0.82]; z = 2.51 (p = 0.01); n = 125; I2 = 0%). The remaining endurance performance surrogates were similarly affected by POL and other TIDs: TT (SMD = - 0.01 [95% CI -0.28, 0.25]; z = - 0.10 (p = 0.92); n = 221; I2 = 0%), TTE (SMD = 0.30 [95% CI - 0.20, 0.79]; z = 1.18 (p = 0.24); n = 66; I2 = 0%) and V/P VT2/LT2 (SMD = 0.04 [95% CI -0.21, 0.29]; z = 0.32 (p = 0.75); n = 253; I2 = 0%). Risk of bias for randomized controlled trials was rated as of some concern and for non-randomized controlled trials as low risk of bias (two studies) and some concerns (one study). CONCLUSIONS: POL is superior to other TIDs for improving VO2peak, particularly in shorter duration interventions and highly trained athletes. However, the effect of POL was similar to that of other TIDs on the remaining surrogates of endurance performance. The results suggest that POL more effectively improves aerobic power but is similar to other TIDs for improving aerobic capacity.


Assuntos
Desempenho Atlético , Treino Aeróbico , Consumo de Oxigênio , Resistência Física , Humanos , Treino Aeróbico/métodos , Resistência Física/fisiologia , Desempenho Atlético/fisiologia
10.
Sports Med ; 54(9): 2373-2394, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38900358

RESUMO

BACKGROUND: The effect of swimming on bone health remains unclear, namely due to discrepant findings between studies in humans and animal models. OBJECTIVE: The aim of this systematic review and meta-analysis is to identify the available evidence on the effects of swimming on bone mass, geometry and microarchitecture at the lumbar spine, femur and tibia in both humans and rodent animal models. METHODS: The study followed PRISMA guidelines and was registered at PROSPERO (CRD4202236347 and CRD42022363714 for human and animal studies). Two different systematic literature searches were conducted in PubMed, Scopus and Web of Science, retrieving 36 and 16 reports for humans and animal models, respectively. RESULTS: In humans, areal bone mineral density (aBMD) was similar between swimmers and non-athletic controls at the lumbar spine, hip and femoral neck. Swimmers' tibia diaphysis showed a higher cross-sectional area but lower cortical thickness. Inconsistent findings at the femoral neck cortical thickness were found. Due to the small number of studies, trabecular microarchitecture in human swimmers was not assessed. In rodent models, aBMD was found to be lower at the tibia, but similar at the femur. Inconsistent findings in femur diaphysis cross-sectional area were observed. No differences in femur and tibia trabecular microarchitecture were found. CONCLUSION: Swimming seems to affect bone health differently according to anatomical region. Studies in both humans and rodent models suggest that tibia cortical bone is negatively affected by swimming. There was no evidence of a negative effect of swimming on other bone regions, both in humans and animal models.


Assuntos
Densidade Óssea , Fêmur , Vértebras Lombares , Natação , Tíbia , Natação/fisiologia , Humanos , Animais , Vértebras Lombares/fisiologia , Fêmur/fisiologia , Fêmur/anatomia & histologia , Tíbia/fisiologia , Modelos Animais
11.
J Clin Med ; 13(17)2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39274434

RESUMO

Objective: This systematic review and meta-analysis aimed to determine the benefits of an exercise intervention based on small-sided soccer games (SSSGs) on health-related physical fitness and cardiometabolic health in previously untrained children and adolescents. Methods: A systematic search on PubMed/MEDLINE, Web of Science, Scopus, Cochrane, and EBSCO databases was performed. Randomized or non-randomized controlled trials conducted in previously untrained children or adolescents (age < 18 years) that assessed the effect of SSSG-based intervention on health-related physical fitness and cardiometabolic risk biomarkers were included. Primary outcomes were cardiorespiratory fitness and waist circumference. Evidence was synthesized as the mean difference or standardized mean difference using a random-effects meta-analysis. The quality of evidence was assessed using ROB2 and ROBINS-I tools. Results: Sixteen studies (n = 2872 participants) were included in this meta-analysis. SSSGs significantly improved cardiorespiratory fitness (SMD, 0.12 [0.01; 0.23]) and showed a non-significant trend in decreased waist circumference (-7.49 cm [-15.03; 0.06]). Additionally, SSSGs significantly decreased systolic (MD, -3.85 mmHg [-5.75; -1.94]) and diastolic blood pressure (MD, -1.26 mmHg [-2.44; -0.08]) and triglycerides (-30.34 mg·dL-1 [-45.99; -14.69]). No effects on body composition or other cardiometabolic risk biomarkers were observed. After a sensitivity analysis, waist circumference and muscle strength were also shown to improve significantly following SSSGs. Comparisons between SSSG and other types of exercise interventions showed no differences in improved physical fitness or cardiometabolic risk. Conclusions: SSSG-based interventions effectively improve cardiorespiratory fitness, blood pressure, triglycerides, muscle strength, and waist circumference. There is less evidence of the effects of SSSGs on other health markers. Particular attention should be given to improving SSSG protocol reporting in future studies.

12.
Obes Surg ; 34(5): 1704-1716, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38532144

RESUMO

PURPOSE: This study examined the benefits of an 11-months multicomponent exercise program (MEP) on muscular strength (MS) after bariatric surgery. METHODS: Of the 84 randomized patients, 41 participants from the exercise group (EG) and 20 participants from the control group (CG) were included in the analysis. The EG received supervised MEP for 11 months, starting 1-month post-bariatric surgery (BS) in addition to standard medical care, while the CG received medical care recommendations only. Knee and trunk MS was assessed by isokinetic dynamometry pre-surgery, 1-, 6-, and 12-month post-surgery, while body composition was assessed by dual-energy X-ray absorptiometry. RESULTS: The MEP did not significantly impact absolute MS in the dominant knee and trunk regions at 6- and 12-month post-BS. However, relative MS showed significant improvements. At 6-month post-BS, knee flexion at 60°/s relative to body weight (BW) increased significantly (p = 0.047), as did knee extension at 180°/s relative to BW (p = 0.009), and knee extension at 60°/s relative to total lean mass (p=0.040). At 12-month post-BS, knee flexion at 60°/s relative to BW also significantly improved (p=0.038). CONCLUSION: While absolute MS was not significantly improved with MEP, this study found significant enhancements in relative MS, particularly in dominant knee flexion post-MEP participation. Further research should explore different exercise intensities and frequencies to optimize postoperative MS recovery post-BS. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov (NCT02843048).


Assuntos
Cirurgia Bariátrica , Obesidade Mórbida , Humanos , Obesidade Mórbida/cirurgia , Exercício Físico , Força Muscular/fisiologia , Terapia por Exercício
13.
Curr Obes Rep ; 13(1): 107-120, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38172484

RESUMO

PURPOSE OF REVIEW: The purpose of this review and meta-analysis is to characterize the changes in body composition of children and adolescents who underwent bariatric surgery and identify possible negative effects of performing this procedure during pediatric ages. RECENT FINDINGS: Bariatric surgery in children and adolescents is an emerging strategy to promote higher and faster body weight and fat mass losses. However, possible negative effects usually observed in surgical patients' muscle-skeletal system raise a major concern perform this intervention during growth. Despite these possible issues, most experimental studies and reviews analyze bariatric surgery's effectiveness only by assessing anthropometric outcomes such as body weight and BMI, disregarding the short- and long-term impact of bariatric surgery on all body composition outcomes. Bariatric surgery is effective to reduce fat mass in adolescents, as well as body weight, waist circumference, and BMI. Significant reduction in lean mass and fat-free mass is also observed. Bone mass seems not to be impaired. All outcomes reduction were observed only in the first 12 months after surgery. Sensitivity analysis suggests possible sex and type of surgery-related differences, favoring a higher fat mass, body weight, and BMI losses in boys and in patients who underwent RYGB.


Assuntos
Cirurgia Bariátrica , Composição Corporal , Índice de Massa Corporal , Obesidade Infantil , Humanos , Adolescente , Obesidade Infantil/cirurgia , Masculino , Feminino , Redução de Peso , Resultado do Tratamento , Criança , Peso Corporal , Obesidade Mórbida/cirurgia
14.
Biomedicines ; 12(1)2023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-38255142

RESUMO

Considering the conflicting evidence regarding the potential long-term detrimental effect of swimming during growth on femur quality and fracture risk, our aim was to investigate the effect of eight months of swimming on femur quality. Twenty male eight-week-old Wistar rats were assigned into a swimming (SW; n = 10; 2 h/day, 5 days/week) or active control group (CG; n = 10, housed with running wheel) for eight months. Plasma osteocalcin and C-terminal telopeptide of type I collagen concentrations (ELISA) were assessed at baseline, four, and eight months of protocol. Femur structure (micro-computed tomography), biomechanical properties (three-point bending), and cellular density (histology) were determined after the protocol. SW displayed a lower uncoupling index, suggesting higher bone resorption, lower empty lacunae density, cortical and trabecular femur mass, femur length and cortical thickness, and higher cortical porosity than CG (p < 0.05). Although both biomarkers' concentrations decreased in both groups throughout the experiment (p < 0.001), there were no significant differences between groups (p > 0.05). No differences were also found regarding biomechanical properties, bone marrow adiposity, and osteocyte and osteoclast densities (p > 0.05). Long-term swimming was associated with unbalanced bone turnover and compromised femur growth, lower femur mass, and deteriorated cortical bone microarchitecture. However, femur trabecular microarchitecture and biomechanical properties were not affected by swimming.

15.
Obesity (Silver Spring) ; 31(11): 2750-2761, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37853990

RESUMO

OBJECTIVE: This study aimed to determine the effects of a multicomponent exercise intervention during the first year post-bariatric surgery (BS) on body composition, weight loss (WL), energy expenditure, and nutrient intake. METHODS: A total of 84 patients were included in this study and were randomly assigned to either an exercise group (n = 41) or a control group (n = 20). The exercise group participated in a multicomponent exercise program that began 1-month post-BS, whereas the control group received only standard medical care post-BS. Body composition was assessed by dual-energy x-ray absorptiometry, and physical activity energy expenditure was assessed by accelerometers. Nutritional intake was assessed through a 4-day food diary. RESULTS: A total of 6-months post-BS, exercise was found to be effective in mitigating the loss of lower-limb and appendicular lean mass (LM), as well as favoring trunk fat mass (FM) loss. Moreover, it further decreased percent FM and promoted additional excess WL. After 12 months, exercise not only reduced waist circumference but also helped to lessen the loss of total, trunk, and appendicular LM. CONCLUSIONS: Exercise further induced trunk fat mass, percent FM, excess WL, and waist circumference reductions. Moreover, exercise attenuated the loss of total and regional LM.


Assuntos
Cirurgia Bariátrica , Composição Corporal , Humanos , Exercício Físico , Redução de Peso , Ingestão de Energia
16.
Eur J Sport Sci ; 23(8): 1518-1527, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35838070

RESUMO

Currently, there is no way to assess mechanical loading variables such as peak ground reaction forces (pGRF) and peak loading rate (pLR) in clinical settings. The purpose of this study was to develop accelerometry-based equations to predict both pGRF and pLR during walking and running. One hundred and thirty one subjects (79 females; 76.9 ± 19.6 kg) walked and ran at different speeds (2-14 km·h-1) on a force plate-instrumented treadmill while wearing accelerometers at their ankle, lower back and hip. Regression equations were developed to predict pGRF and pLR from accelerometry data. Leave-one-out cross-validation was used to calculate prediction accuracy and Bland-Altman plots. Our pGRF prediction equation was compared with a reference equation previously published. Body mass and peak acceleration were included for pGRF prediction and body mass and peak acceleration rate for pLR prediction. All pGRF equation coefficients of determination were above 0.96, and a good agreement between actual and predicted pGRF was observed, with a mean absolute percent error (MAPE) below 7.3%. Accuracy indices from our equations were better than previously developed equations. All pLR prediction equations presented a lower accuracy compared to those developed to predict pGRF. Walking and running pGRF can be predicted with high accuracy by accelerometry-based equations, representing an easy way to determine mechanical loading in free-living conditions. The pLR prediction equations yielded a somewhat lower prediction accuracy compared with the pGRF equations.


Peak ground reaction forces can be accurately predicted through raw accelerometry data.These predictions are valid for a broad range of body masses and for ankle, lower back and hip accelerometer placements.Peak loading rate prediction presented lower accuracy compared with peak ground reaction force prediction.These findings result in a simple method to predict mechanical loading in clinical practice, which is relevant in some areas of sports medicine such as bone health and injury prevention.


Assuntos
Corrida , Caminhada , Feminino , Humanos , Acelerometria , Tornozelo , Articulação do Tornozelo , Fenômenos Biomecânicos
17.
J Bone Miner Metab ; 30(3): 281-92, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21938383

RESUMO

Bone strength depends on several material and structural properties, but findings concerning the best predictors of bone mechanical performance are conflicting. The aim of this study was to investigate how a broad set of bone properties in the proximal femur are influenced by age and hormonal status, and how these properties together determine bone strength. Twenty-five Wistar rats were ovariectomized (OVX, n = 13) or sham operated (SHAM, n = 12) at 5 months of age, and killed after 9 months. Another group of rats was killed at 5 months as baseline control (BSL, n = 7). At sacrifice, serum 17ß-estradiol and bone turnover marker concentrations were determined in the serum. Both femurs were collected for assessment of trabecular microarchitecture, femoral neck geometry, radiographic absorptiometry, calcium and phosphate content, and biomechanical properties. While stiffness was mostly associated with proximal femur trabecular microarchitecture and mineralization degree, bone strength was mostly linked to bone size and femoral neck geometry, which predicted almost 50% of its variance. Despite the decrease in cortical and trabecular bone as well as in mineralization degree following estrogen loss, bone strength was not reduced in OVX animals compared to BSL or sham-operated rats. This was due to a change in femoral neck geometry as well as to an increase in femur size in OVX, which apparently compensated their lower bone volume and mineral content, thereby preserving bone strength. Estrogen loss leads to a deterioration of bone tissue quality, but bone strength was preserved at the expense of geometric adaptations.


Assuntos
Fêmur/patologia , Fêmur/fisiologia , Fraturas Ósseas/patologia , Ovariectomia , Animais , Fenômenos Biomecânicos , Peso Corporal , Feminino , Fêmur/diagnóstico por imagem , Fêmur/fisiopatologia , Fraturas Ósseas/diagnóstico por imagem , Fraturas Ósseas/fisiopatologia , Tamanho do Órgão , Ovariectomia/efeitos adversos , Radiografia , Ratos , Ratos Wistar
18.
Obes Surg ; 32(6): 2056-2068, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35332396

RESUMO

We aimed to determine the effects of different exercise types, duration, and onset after bariatric surgery (BS) on cardiometabolic risk factors (CMRFs). A systematic search was conducted up to July 2021. Eleven studies were identified (n = 618 participants). Overall, exercise induced reductions in systolic blood pressure (SBP; - 5.33 mmHg; 95%CI - 8.99, -1.66; p < 0.01). Combined exercises elicited reductions on SBP (- 7.18 mmHg; 95%CI - 12.42, - 1.94; p < 0.01) and triglycerides (- 17.56 mg/dL; 95%CI - 34.15, - 0.96; p = 0.04). SBP reductions were also observed on interventions starting > 6 months post-BS (- 7.71 mmHg; 95%CI - 13.12, - 2.31; p < 0.01), and on > 12-week protocols (- 5.78 mmHg; 95%CI - 9.91, - 1.66; p < 0.01). Overall exercise and particularly aerobic plus resistance protocols were an effective therapy to reduce CMRFs post-BS. Benefits were also observed with interventions starting > 6 months post-BS and with > 12-week duration. Trial registration: CRD42020161175 .


Assuntos
Cirurgia Bariátrica , Doenças Cardiovasculares , Obesidade Mórbida , Pressão Sanguínea , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/prevenção & controle , Humanos , Obesidade/cirurgia , Obesidade Mórbida/cirurgia , Ensaios Clínicos Controlados Aleatórios como Assunto
19.
Obes Sci Pract ; 8(1): 112-123, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35127127

RESUMO

BACKGROUND: Bariatric surgery is the most effective treatment for patients with severe obesity, but success rates vary substantially. Exercise is recommended after bariatric surgery to reduce weight regain but the effectiveness remains undetermined on weight loss due to conflicting results. It is also unclear what should be the optimal exercise prescription for these patients. A systematic review and meta-analysis of randomized controlled trials on the effects of exercise on body weight (BW), anthropometric measures, and body composition after bariatric surgery was performed. METHODS: PubMed/MEDLINE®, EBSCO®, Web of Science® and Scopus® databases were searched to identify studies evaluating exercise effectiveness. RESULTS: The analysis comprised 10 studies (n = 487 participants). Exercise favored BW (-2.51kg; p = 0.02), waist circumference (-4.14cm; p = 0.04) and body mass index (-0.84kg·m-2; p = 0.02) reduction but no improvements in body composition. Combined exercise interventions were the most effective in reducing BW (-5.50kg; p < 0.01) and body mass index (-1.86kg·m-2; p < 0.01). Interventions starting >6-months after bariatric surgery were more successful in reducing BW (-5.02kg; p < 0.01) and body mass index (-1.62kg·m-2; p < 0.01). CONCLUSION: Exercise, combined exercise regimens and interventions starting >6-months after bariatric surgery were effective in promoting BW, waist circumference and body mass index reduction. Exercise following bariatric surgery does not seem to favor body composition improvements.

20.
Obes Surg ; 32(3): 912-923, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35031954

RESUMO

We aimed to assess if exercise applied after bariatric surgery (BS) improves bone mineral density (BMD) compared to usual care. Systematic search was conducted up to January 2021. Effect measures were determined using standardized mean difference (SMD) with 95% confidence interval (CI). Certainty evidence was assessed according to GRADE. Four clinical trials encompassing 340 patients were included. Exercise induced a positive BMD effect at total hip (SMD = 0.37 [95% CI 0.02, 0.71]; very low certainty evidence), femoral neck (SMD = 0.63 [95% CI 0.19, 1.06]; low certainty evidence), lumbar spine (SMD = 0.41 [95% CI 0.19, 0.62]; low certainty evidence), and 1/3 radius (SMD = 0.58 [95% CI 0.19, 0.97]; low certainty evidence). Exercise undertaken after BS seems to induce a positive effect on BMD.


Assuntos
Cirurgia Bariátrica , Obesidade Mórbida , Densidade Óssea , Exercício Físico , Colo do Fêmur , Humanos , Obesidade Mórbida/cirurgia
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