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1.
Artigo em Inglês | MEDLINE | ID: mdl-37569078

RESUMO

The current study analysed whether the osteogenic stimuli of exercises and sports have an independent effect on bone mineral density (BMD). Studies with a design having two different cohorts were searched and selected to distinguish the effect due to long-term involvement (i.e., athletes vs. non-active young with good bone health) and due to the planning of intervention (i.e., pre- vs. post-training) with exercises and sports. Moreover, only studies investigating the bone sites with a body-weight support function (i.e., lower limb, hip, and spine regions) were reviewed, since the osteogenic effects have incongruous results. A meta-analysis was performed following the recommendations of PRISMA. Heterogeneity (I2) was determined by combining Cochran's Q test with the Higgins test, with a significance level of α = 0.05. The studies reporting the effect of involvement in exercise and sports showed high heterogeneity for the lower limb, total hip, and spine (I2 = 90.200%, 93.334%, and 95.168%, respectively, with p < 0.01) and the effect size on sports modalities (Hedge's g = 1.529, 1.652, and 0.417, respectively, with p < 0.05) ranging from moderate to high. In turn, the studies reporting the effect of the intervention planning showed that there was no heterogeneity for the lower limb (I2 = 0.000%, p = 0.999) and spine (I2 = 77.863%, p = 0.000); however, for the hip, it was moderate (I2 = 49.432%, p = 0.054), with a low effect between the pre- and post-training moments presented only for the hip and spine (Hedge's g = 0.313 and 0.353, respectively, with p < 0.05). The current analysis supported the effect of involvement in exercise and sports by evidencing the effect of either weight-bearing or non-weight-bearing movements on BMD at the femoral, pelvic, and lumbar bones sites of the athletes when comparing to non-athletes or non-active peers with healthy bones. Moreover, the effect of different exercise and sports interventions highlighted the alterations in the BMD in the spine bone sites, mainly with long-term protocols (~12 months) planned with a stimulus with high muscle tension. Therefore, exercise and sport (mainly systematic long-term practice) have the potential to increase the BMD of bones with body-weight support beyond the healthy values reached during life phases of youth and adulthood.


Assuntos
Perna (Membro) , Esportes , Adolescente , Humanos , Exercício Físico/fisiologia , Osso e Ossos , Densidade Óssea/fisiologia , Extremidade Inferior
2.
Genet Sel Evol ; 55(1): 36, 2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37268883

RESUMO

BACKGROUND: In breeding programmes, the observed genetic change is a sum of the contributions of different selection paths represented by groups of individuals. Quantifying these sources of genetic change is essential for identifying the key breeding actions and optimizing breeding programmes. However, it is difficult to disentangle the contribution of individual paths due to the inherent complexity of breeding programmes. Here we extend the previously developed method for partitioning genetic mean by paths of selection to work both with the mean and variance of breeding values. METHODS: First, we extended the partitioning method to quantify the contribution of different paths to genetic variance assuming that the breeding values are known. Second, we combined the partitioning method with the Markov Chain Monte Carlo approach to draw samples from the posterior distribution of breeding values and use these samples for computing the point and interval estimates of partitions for the genetic mean and variance. We implemented the method in the R package AlphaPart. We demonstrated the method with a simulated cattle breeding programme. RESULTS: We show how to quantify the contribution of different groups of individuals to genetic mean and variance and that the contributions of different selection paths to genetic variance are not necessarily independent. Finally, we observed that the partitioning method under the pedigree-based model has some limitations, which suggests the need for a genomic extension. CONCLUSIONS: We presented a partitioning method to quantify sources of change in genetic mean and variance in breeding programmes. The method can help breeders and researchers understand the dynamics in genetic mean and variance in a breeding programme. The developed method for partitioning genetic mean and variance is a powerful method for understanding how different selection paths interact within a breeding programme and how they can be optimised.


Assuntos
Genoma , Genômica , Animais , Bovinos/genética , Método de Monte Carlo , Linhagem , Cadeias de Markov , Modelos Genéticos , Seleção Genética
3.
J Sports Med Phys Fitness ; 63(1): 77-85, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35437303

RESUMO

INTRODUCTION: Currently, there is an increase in people practicing freediving (FD) both in competition and leisure. As a sports practice, its modalities are grouped into static, dynamic, and constant weight apnea. The aim of this systematic review and meta-analysis (PROSPERO-CRD42021230322) was to identify the training methods used to improve the static apnea time (AT) performance. EVIDENCE ACQUISITION: Ten training protocols were analyzed from eight studies published until March 09, 2022. The effect size (Hedge's g) and its confidence interval (CI95%) were calculated from the AT measured pre- and post-training. EVIDENCE SYNTHESIS: Three different apnea training methods were verified, the breath-hold (BH) that uses BH exercises, physical training with strength and cardiorespiratory exercises, and cross training that combines BH exercises with physical training. These training methods were applied to 138 participants of both sexes with or without experience in apnea episode or diving practice. In general, the AT improvement showed a large effect after the interventions (g=1.30, CI95%=0.85-1.76, P<0.01). CONCLUSIONS: All three methods were effective in improving static AT, however from the existing protocols is not possible to recommend an ideal to improve AT and therefore FD performance.


Assuntos
Apneia , Mergulho , Masculino , Feminino , Humanos , Apneia/terapia , Suspensão da Respiração , Exercício Físico , Terapia por Exercício
4.
J Bone Miner Metab ; 41(1): 113-123, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36422677

RESUMO

INTRODUCTION: This study aimed to compare athletes practicing exercise in different environments with non-active young and elderly men and women regarding bone mineral density (BMD), hypothesizing that BMD values differ between athletes according to the environment of exercise practice, but those training in a low-gravitational environment have no different stimuli to BMD increasing if compared with healthy peers experiencing reduced exercise involvement, whatever the age group and sex. MATERIALS AND METHODS: 104 participants of both sexes were selected according to the environment of exercise practice [swimmers (N = 26) and judo fighters (N = 26)], and exercise level of involvement [non-active young (N = 26) and older adults (N = 26)]. Dual-energy X-ray absorptiometry provided BMD, lean mass, and fat mass (FM) for the whole body (WB), upper (UL), and lower limbs (LL). RESULTS: For the BMD in WB, UL and LL no effects of group and sex were observed (p > 0.05). Post-hoc analyses detected higher values of BMD in UL for female swimmers compared to non-active older adults (p < 0.05), while judo fighters showed higher BMD in WB, UL, and LL than other participants whatever the sex (p < 0.01). Lower FM was observed for WB, UL, and LL when swimmers and judo fighters were compared to non-active young and older female peers (p < 0.01). CONCLUSION: The findings emphasized that BMD stimuli with swimming are reduced when compared to judo, and despite the stimuli in swimming is not distinguishable from that affecting BMD in WB, UL and LL of non-active young, it is effective in differing BMD in UL among non-active older for women.


Assuntos
Composição Corporal , Osso e Ossos , Masculino , Humanos , Feminino , Idoso , Densidade Óssea , Absorciometria de Fóton , Natação , Minerais
5.
Int J Cardiol ; 369: 77-79, 2022 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-35944769

RESUMO

INTRODUCTION: Thrombolysis is currently reserved for ST-elevation myocardial infarction (STEMI) patients who cannot access timely percutaneous coronary intervention (PCI). In case of failed thrombolysis, rescue PCI is a viable option. Substantial data concerning the outcomes in terms of infarct size and myocardial function after rescue PCI are lacking. METHODS: Forty patients treated with rescue PCI underwent serial contrast-enhanced cardiac magnetic resonance imaging (CMR) at 1 week, 3 months and 6 months from the index STEMI. Angiographic images were reviewed to assess Thrombolysis in Myocardial Infarction (TIMI) blood flow and TIMI Myocardial Blush Grade (TMBG) in the infarct related artery after PCI. RESULTS: Patients with lower TMBG at the end of procedure, but not patients with worse TIMI flow, had lower left ventricular ejection fraction (LVEF) and higher volume of late gadolinium enhancement (LGE) on baseline CMR (44 ± 13% vs 52 ± 9%, p = 0.026, and 41 ± 21 ml vs 26 ± 12, p = 0.030, respectively). Patients with lower TMBG remained with significantly lower LVEF at 6 months follow up (48 ± 16% vs 59 ± 14, p = 0.049). CONCLUSION: TMBG after rescue PCI is associated with reduced LVEF and increased LGE burden. As TMBG is a known marker of microvascular damage after STEMI, novel strategies aimed at improving microvascular function in the setting of rescue PCI are needed to improve the outcomes in this patient population.


Assuntos
Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Angioplastia , Afogueamento , Meios de Contraste , Angiografia Coronária/métodos , Circulação Coronária/fisiologia , Gadolínio , Humanos , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico por imagem , Infarto do Miocárdio com Supradesnível do Segmento ST/cirurgia , Volume Sistólico , Resultado do Tratamento , Função Ventricular Esquerda
6.
Healthcare (Basel) ; 10(6)2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35742181

RESUMO

Resistance training (RT) has been considered an intervention with effective stimulus on bone mineral formation and is, therefore, recommended to decrease the rate of bone morpho-functional proprieties loss with aging. Thus, this meta-analysis aimed to analyze the effectiveness of RT protocols in promoting changes in bone mineral density (BMD) in older adults. The systematic reviews and meta-analysis followed the PRISMA guidelines (PROSPERO CRD42020170859). The searches were performed in the electronic databases using descriptors according to the PICO strategy. The methodological quality and risk of bias were assessed with the PEDro scale, and the magnitude of the results was determined by Hedges' g. Seven studies involving 370 elderlies, with the RT planned as a unique exercise mode of intervention, showed designs with four to five exercises for upper- and lower-limbs musculature, two to three sets per exercise, eight to twelve repetitions to failure at 70-90% 1 RM, 60-120 s of rest between sets, and executed three times per week for 12-52 weeks. The RT protocols were classified between good and excellent and evidenced a positive effect on the BMD at the hip (0.64%) and spine (0.62%) but not in the femoral neck (-0.22%) regardless of the intervention length. The narrow range of either positive or negative changes in the BMD after the RT intervention support, at best, a preventive effect against the increasing risk of bone frailty in an older population, which is evident beyond 12 weeks of RT practice engagement.

7.
Int J Exerc Sci ; 15(3): 561-569, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35516414

RESUMO

The purpose of the present study was to assess performance and morphological acute responses to the tri-set (TRI) resistance-training system. In a random order, 18 subjects (years: 30.0 ± 5.6; weight: 81.8 ± 13.4 kg; height: 173 ± 6.2 cm; RT experience: 4.6 ± 1.7 years) performed 3 exercises targeting the pectoralis major muscle in two different experimental conditions: traditional system (TRAD) and TRI. The TRAD protocol referred to the completion of a single exercise set followed by a rest period. For the TRI protocol, one set of each exercise was performed sequentially with a minimal rest interval afforded (< 10 seconds). Both protocols were performed in 3 sets of 10RM. Pectoralis major muscle swelling (PMMS), volume load (VL), internal training load (ITL) and training efficiency (TE) were calculated and compared between both protocols. Despite the low VL (-19.3%; p < 0.001), larger values of PMMS (104.7%; p < 0.001), ITL (24.3%; p < 0.001) and TE (56.0%; p < 0.001) were observed during TRI compared to TRAD condition. In conclusion, the adoption of a TRI training protocol may induce distinct performance and morphological acute responses compared to TRAD, suggesting that resistance-trained subjects may experience a higher muscle swelling and intensity of effort with short time commitment when performing TRI system.

8.
PeerJ ; 8: e9850, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32995081

RESUMO

BACKGROUND AND OBJECTIVE: Observational studies and experiments in medicine, pharmacology and agronomy are often concerned with assessing whether different methods/raters produce similar values over the time when measuring a quantitative variable. This article aims to describe the statistical package lcc, for are, that can be used to estimate the extent of agreement between two (or more) methods over the time, and illustrate the developed methodology using three real examples. METHODS: The longitudinal concordance correlation, longitudinal Pearson correlation, and longitudinal accuracy functions can be estimated based on fixed effects and variance components of the mixed-effects regression model. Inference is made through bootstrap confidence intervals and diagnostic can be done via plots, and statistical tests. RESULTS: The main features of the package are estimation and inference about the extent of agreement using numerical and graphical summaries. Moreover, our approach accommodates both balanced and unbalanced experimental designs or observational studies, and allows for different within-group error structures, while allowing for the inclusion of covariates in the linear predictor to control systematic variations in the response. All examples show that our methodology is flexible and can be applied to many different data types. CONCLUSIONS: The lcc package, available on the CRAN repository, proved to be a useful tool to describe the agreement between two or more methods over time, allowing the detection of changes in the extent of agreement. The inclusion of different structures for the variance-covariance matrices of random effects and residuals makes the package flexible for working with different types of databases.

9.
Phytopathology ; 109(2): 286-293, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30451635

RESUMO

Xylella fastidiosa subsp. pauca is genetically diverse and has many vector species. However, there is limited information on vector specificity and efficiency for different sequence types (STs) within the pathogen subspecies. Both STs of X. fastidiosa and vectors differ in their associations with plants; therefore, assessment of vector competence should include the standardized vector acquisition ability of bacteria from artificial diets. This work aimed to adapt and validate an in vitro acquisition system for strains of X. fastidiosa that cause citrus variegated chlorosis, and to compare the transmission efficiency of STs of subsp. pauca by different species of sharpshooter vector. First, acquisition and transmission of ST13 by Bucephalogonia xanthophis and Macugonalia leucomelas was tested using an artificial diet with bacteria grown on minimum defined medium (X. fastidiosa medium) with or without 1% galacturonic acid (GA). Subsequently, four sharpshooter species (B. xanthophis, M. leucomelas, M. cavifrons, and Sibovia sagata) were compared as vectors of ST13 acquired from artificial diets, and four STs of subsp. pauca (11, 13, 65, and 70) were tested for acquisition and transmission by M. leucomelas. The artificial system allowed efficient acquisition and transmission of ST13 to plants, with no differences between the media tested. ST13 was transmitted more efficiently by B. xanthophis and M. leucomelas when compared with M. cavifrons and S. sagata. Different STs influenced acquisition and transmission rates by M. leucomelas. The differences in vector competence, despite the standardized acquisition system, suggest that ST-vector foregut or vector-plant interactions may influence bacterial acquisition, retention and inoculation by the insect.


Assuntos
Citrus , Hemípteros , Xylella , Animais , Hemípteros/microbiologia , Insetos Vetores , Insetos , Doenças das Plantas/microbiologia
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