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1.
JAMA Pediatr ; 177(2): 132-140, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36595284

RESUMO

Importance: Depression is the second most prevalent mental disorder among children and adolescents, yet only a small proportion seek or receive disorder-specific treatment. Physical activity interventions hold promise as an alternative or adjunctive approach to clinical treatment for depression. Objective: To determine the association of physical activity interventions with depressive symptoms in children and adolescents. Data Sources: PubMed, CINAHL, PsycINFO, EMBASE, and SPORTDiscus were searched from inception to February 2022 for relevant studies written in English, Chinese, or Italian. Study Selection: Two independent researchers selected studies that assessed the effects of physical activity interventions on depressive symptoms in children and adolescents compared with a control condition. Data Extraction and Synthesis: A random-effects meta-analysis using Hedges g was performed. Heterogeneity, risk of bias, and publication bias were assessed independently by multiple reviewers. Meta-regressions and sensitivity analyses were conducted to substantiate the overall results. The study followed the PRISMA reporting guideline. Main Outcomes and Measures: The main outcome was depressive symptoms as measured by validated depression scales at postintervention and follow-up. Results: Twenty-one studies involving 2441 participants (1148 [47.0%] boys; 1293 [53.0%] girls; mean [SD] age, 14 [3] years) were included. Meta-analysis of the postintervention differences revealed that physical activity interventions were associated with a reduction in depressive symptoms compared with the control condition (g = -0.29; 95% CI, -0.47 to -0.10; P = .004). Analysis of the follow-up outcomes in 4 studies revealed no differences between the physical activity and control groups (g = -0.39; 95% CI, -1.01 to 0.24; P = .14). Moderate study heterogeneity was detected (Q = 53.92; df = 20; P < .001; I2 = 62.9% [95% CI, 40.7%-76.8%]). The primary moderator analysis accounting for total physical activity volume, study design, participant health status, and allocation and/or assessment concealment did not moderate the main treatment effect. Secondary analyses demonstrated that intervention (ie, <12 weeks in duration, 3 times per week, unsupervised) and participant characteristics (ie, aged ≥13 years, with a mental illness and/or depression diagnosis) may influence the overall treatment effect. Conclusions and Relevance: Physical activity interventions may be used to reduce depressive symptoms in children and adolescents. Greater reductions in depressive symptoms were derived from participants older than 13 years and with a mental illness and/or depression diagnosis. The association with physical activity parameters such as frequency, duration, and supervision of the sessions remains unclear and needs further investigation.


Assuntos
Depressão , Transtornos Mentais , Masculino , Feminino , Humanos , Criança , Adolescente , Depressão/prevenção & controle , Depressão/diagnóstico , Exercício Físico , Promoção da Saúde , Nível de Saúde
2.
Lancet Child Adolesc Health ; 7(1): 47-58, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36309037

RESUMO

BACKGROUND: Individuals affected by childhood cancer can have cognitive dysfunction that persists into adulthood and negatively affects quality of life. In this study, we aimed to evaluate the effects of physical activity and exercise on cognitive function among individuals affected by childhood cancer. METHODS: In this systematic review and meta-analysis, we searched seven databases (CINAHL Plus, Cochrane Library, Embase, MEDLINE, PsycINFO, SPORTDiscus, and Web of Science) and two clinical trial registries (ClinicalTrials.gov and the International Clinical Trials Registry Platform) for randomised controlled trials (RCTs) and non-randomised studies of interventions (NRSIs) published (or registered) from database inception to Jan 30, 2022, with no language restrictions. We included studies that compared the effects of physical activity or exercise interventions with controls (no intervention or usual care) on cognitive function among individuals diagnosed with any type of cancer at age 0-19 years. Two reviewers (JDKB and FR) independently screened records for eligibility and searched references of the selected studies; extracted study-level data from published reports; and assessed study risk of bias of RCTs and NRSIs using the Cochrane risk of bias tool for randomised trials (RoB 2) and Risk Of Bias In Non-randomised Studies-of Interventions (ROBINS-I) tools, certainty of the evidence using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach, and any adverse events. We used intention-to-treat data and unpublished data if available. Cognitive function was assessed by standardised cognitive performance measures (primary outcome) and by validated patient-reported measures (secondary outcome). A random-effects meta-analysis model using the inverse-variance and Hartung-Knapp methods was used to calculate pooled estimates (Hedges' g) and 95% CI values. We estimated the heterogeneity variance by the restricted maximum likelihood method and calculated I2 values to measure heterogeneity. We examined funnel plots and used Egger's regression test to assess for publication bias. This study is registered with PROSPERO, CRD42021261061. FINDINGS: We screened 12 425 titles and abstracts, which resulted in full-text assessment of 131 potentially relevant reports. We evaluated 22 unique studies (16 RCTs and six NRSIs) with data on 1277 individuals affected by childhood cancer and low-to-moderate risk of bias. Of the 1277 individuals, 674 [52·8%] were male and 603 [47·2%] were female; median age at study start was 12 (IQR 11-14) years, median time since the end of cancer treatment was 2·5 (IQR -1·1 to 3·0) years, and median intervention period was 12 [IQR 10-24] weeks. There was moderate-quality evidence that, compared with control, physical activity and exercise improved cognitive performance measures (five RCTs; Hedges' g 0·40 [95% CI 0·07-0·73], p=0·027; I2=18%) and patient-reported measures of cognitive function (13 RCTs; Hedges' g 0·26 [0·09-0·43], p=0·0070; I2=40%). No evidence of publication bias was found. Nine mild adverse events were reported. INTERPRETATION: There is moderate-certainty evidence that physical activity and exercise improves cognitive function among individuals affected by childhood cancer, which supports the use of physical activity for managing cancer-related cognitive impairment. FUNDING: Research Impact Fund of Research Grants Council of the Hong Kong University Grants Committee (R7024-20) and Seed Fund for Basic Research of the University of Hong Kong. COPYRIGHT: © 2022 Published by Elsevier Ltd. All rights reserved.


Assuntos
Disfunção Cognitiva , Neoplasias , Masculino , Feminino , Humanos , Criança , Adulto , Recém-Nascido , Lactente , Pré-Escolar , Adolescente , Adulto Jovem , Exercício Físico , Neoplasias/complicações , Neoplasias/terapia , Qualidade de Vida , Disfunção Cognitiva/terapia , Hong Kong
3.
Front Physiol ; 13: 1028345, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36467694

RESUMO

In the heart, alternative splicing of the igf-I gene produces two isoforms: IGF-IEa and IGF-IEc, (Mechano-growth factor, MGF). The sequence divergence between their E-domain regions suggests differential isoform function. To define the biological actions of MGF's E-domain, we performed in silico analysis of the unique C-terminal sequence and identified a phosphorylation consensus site residing within a putative 14-3-3 binding motif. To test the functional significance of Ser 18 phosphorylation, phospho-mimetic (S/E18) and phospho-null (S/A18) peptides were delivered to mice at different doses for 2 weeks. Cardiovascular function was measured using echocardiography and a pressure-volume catheter. At the lowest (2.25 mg/kg/day) and highest (9 mg/kg/day) doses, the peptides produced a depression in systolic and diastolic parameters. However, at 4.5 mg/kg/day the peptides produced opposing effects on cardiac function. Fractional shortening analysis also showed a similar trend, but with no significant change in cardiac geometry. Microarray analysis discovered 21 genes (FDR p < 0.01), that were expressed accordant with the opposing effects on contractile function at 4.5 mg/kg/day, with the nuclear receptor subfamily 4 group A member 2 (Nr4a2) identified as a potential target of peptide regulation. Testing the regulation of the Nr4a family, showed the E-domain peptides modulate Nr4a gene expression following membrane depolarization with KCl in vitro. To determine the potential role of 14-3-3 proteins, we examined 14-3-3 isoform expression and distribution. 14-3-3γ localized to the myofilaments in neonatal cardiac myocytes, the cardiac myocytes and myofilament extracts from the adult heart. Thermal shift analysis of recombinant 14-3-3γ protein showed the S/A18 peptide destabilized 14-3-3γ folding. Also, the S/A18 peptide significantly inhibited 14-3-3γ's ability to interact with myosin binding protein C (MYPC3) and phospholamban (PLN) in heart lysates from dobutamine injected mice. Conversely, the S/E18 peptide showed no effect on 14-3-3γ stability, did not inhibit 14-3-3γ's interaction with PLN but did inhibit the interaction with MYPC3. Replacing the glutamic acid with a phosphate group on Ser 18 (pSer18), significantly increased 14-3-3γ protein stability. We conclude that the state of Ser 18 phosphorylation within the 14-3-3 binding motif of MGF's E-domain, modulates protein-protein interactions within the 14-3-3γ interactome, which includes proteins involved in the regulation of contractile function.

4.
Circ Cardiovasc Qual Outcomes ; 15(6): e008243, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35477256

RESUMO

BACKGROUND: Although regular exercise is recommended for preventing and treating overweight/obesity, the most effective exercise type for improving cardiometabolic health in individuals with overweight/obesity remains largely undecided. This network meta-analysis aimed to evaluate and rank the comparative efficacy of 5 exercise modalities on cardiometabolic health measures in individuals with overweight/obesity. METHODS: A database search was conducted in MEDLINE, Embase, Scopus, and Web of Science from inception up to September 2020. The review focused on randomized controlled trials involving exercise interventions consisting of continuous endurance training, interval training, resistance training, combined aerobic and resistance training (combined training), and hybrid-type training. Exercise interventions aimed to improve somatometric variables, body composition, lipid metabolism, glucose control, blood pressure, cardiorespiratory fitness, and muscular strength. The Cochrane risk of bias tool was used to evaluate eligible studies. A random-effects network meta-analysis was performed within a frequentist framework. The intervention ranking was carried out using a Bayesian model where mean and SD were equal to the respective frequentist estimates. RESULTS: A total of 4331 participants (59% female; mean age: 38.7±12.3 years) from 81 studies were included. Combined training was the most effective modality and hybrid-type training the second most effective in improving cardiometabolic health-related outcomes in these populations suggesting a higher efficacy for multicomponent exercise interventions compared to single-component modalities, that is, continuous endurance training, interval training, and resistance training. A subgroup analysis revealed that the effects from different exercise types were mediated by gender. CONCLUSIONS: These findings corroborate the latest guidelines on exercise for individuals with overweight/obesity highlighting the importance of a multicomponent exercise approach to improve cardiometabolic health. Physicians and healthcare professionals should consider prescribing multicomponent exercise interventions to adults with overweight/obesity to maximize clinical outcomes. REGISTRATION: URL: https://www.crd.york.ac.uk/PROSPERO/; Unique identifier: CRD42020202647.


Assuntos
Doenças Cardiovasculares , Sobrepeso , Adulto , Teorema de Bayes , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/prevenção & controle , Exercício Físico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metanálise em Rede , Obesidade/diagnóstico , Obesidade/terapia , Sobrepeso/diagnóstico , Sobrepeso/terapia , Ensaios Clínicos Controlados Aleatórios como Assunto
5.
Pflugers Arch ; 474(3): 267-279, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34820713

RESUMO

14-3-3 proteins (14-3-3 s) are a family of highly conserved proteins that regulate many cellular processes in eukaryotes by interacting with a diverse array of client proteins. The 14-3-3 proteins have been implicated in several disease states and previous reviews have condensed the literature with respect to their structure, function, and the regulation of different cellular processes. This review focuses on the growing body of literature exploring the important role 14-3-3 proteins appear to play in regulating the biochemical and biophysical events associated with excitation-contraction coupling (ECC) in muscle. It presents both a timely and unique analysis that seeks to unite studies emphasizing the identification and diversity of 14-3-3 protein function and client protein interactions, as modulators of muscle contraction. It also highlights ideas within these two well-established but intersecting fields that support further investigation with respect to the mechanistic actions of 14-3-3 proteins in the modulation of force generation in muscle.


Assuntos
Proteínas 14-3-3 , Acoplamento Excitação-Contração , Proteínas 14-3-3/metabolismo , Cálcio/metabolismo , Acoplamento Excitação-Contração/fisiologia , Humanos , Contração Muscular/fisiologia , Músculo Esquelético/metabolismo
6.
Am J Health Promot ; 36(2): 328-339, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34809485

RESUMO

OBJECTIVE: To evaluate the effects of walking, independent of diet and weight-loss, on lipids and lipoproteins in women with overweight and obesity. DATA SOURCE: Academic Search Complete, Alternative Health Watch, Global Health, Health Source, CINAHL, MEDLINE, EMBASE, SportDiscus, and ProQuest. STUDY INCLUSION AND EXCLUSION CRITERIA: (1) experiment-control design; (2) women with overweight or obesity; (3) walking as the experiment's independent variable; (4) four or more weeks; and (5) pre- to post-assessment of lipids and/or lipoproteins. Excluded studies reported use of lipid-lowering medication, diet or other modes of physical activity, and alternative interventions as the control. DATA EXTRACTION: Data extraction and study quality were completed by the first 2 authors using the Cochrane review protocol and risk of bias assessment. DATA SYNTHESIS: Raw mean difference between the experiment and control groups using a random effects model. RESULTS: Meta-analyses of 21 interventions (N = 1129) demonstrated exclusive walking improves total cholesterol (raw mean difference = 6.67 mg/dL, P = .04) and low-density lipoproteins (raw mean difference = 7.38 mg/dL, P = .04). Greater improvement in total cholesterol, triglycerides, high-density lipoproteins, and low-density lipoproteins existed in women with obesity. CONCLUSIONS: Exclusive walking aids in normalizing total cholesterol and LDLs in women with overweight and obesity. Exclusive walking can be used as a non-pharmacologic therapy, which may have positive clinical outcomes for individuals who especially struggle with diet and weight-reduction.


Assuntos
Obesidade , Sobrepeso , Feminino , Humanos , Lipoproteínas , Obesidade/terapia , Sobrepeso/terapia , Caminhada , Redução de Peso
7.
Disabil Rehabil ; 43(24): 3503-3514, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33331790

RESUMO

BACKGROUND AND PURPOSE: In 1994, the International Paralympic Committee (IPC) established the IPC Sport Science Committee in an effort to bring Paralympic Movement relevant research questions to the academic world. In 1996, the IPC Sport Science Committee put an application system in place, allowing scholars to conduct research at the Paralympic Games. The aim of this perspective paper is to overview the main outcomes of the fifty-six research projects conducted from Atlanta 1996 until PyeongChang 2018 during Paralympic Games' time; and to discuss the state-of-the-art of the IPC Research Strategic Goals. METHODS: Research projects conducted at the Paralympic Games from Atlanta 1996 to PyeongChang 2018 were clustered according to the IPC Research Strategic Goals (publications retrieved through the following procedure: analyzing the IPC Medical & Scientific Department project file; systematic search of Pubmed and SportDiscus with "Name Principal Investigator" and "Paralympic" as search terms; email to principal investigator if no outcome retrieved). RESULTS: Games-time projects targeted Paralympic research strategic goals, such as athletes' health, athletes' performance, evidence-based classification, participation, Paralympic legacy, and education. CONCLUSION: Some of the projects proved high relevance and became standard Games' operations; however, generally, projects operate in isolation and could benefit from collaboration with expert-stakeholders (e.g., athletes, coaches, governing International Sport Federations, relevant IPC departments, network of academic scholars). Sport science research in the Paralympic Movement should move fast and collaborative to catch up on evolution.IMPLICATIONS FOR REHABILITATIONFrom a health perspective, fine-tuning of the patient/athlete-equipment interface to optimize function/performance is a challenge for the rehabilitation specialist/coach.The musculoskeletal balance of the shoulder joints is a lifelong concern for permanent wheelchair users, especially those involved in dynamic wheelchair sports.Education about autonomic dysreflexia and boosting in patients/athletes with spinal cord injury is an integral part of the rehabilitation process.Rehabilitation experts have an ideal educational profile to contribute to evidence-based classification, as a para-sports classifier, or as a researcher.


Assuntos
Desempenho Atlético , Traumatismos da Medula Espinal , Esportes para Pessoas com Deficiência , Atletas , Humanos
8.
Am J Lifestyle Med ; 14(5): 511-523, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32922236

RESUMO

There is overwhelming evidence in the scientific and medical literature that physical inactivity is a major public health problem with a wide array of harmful effects. Over 50% of health status can be attributed to unhealthy behaviors with smoking, diet, and physical inactivity as the main contributors. Exercise has been used in both the treatment and prevention of a variety of chronic conditions such as heart disease, pulmonary disease, diabetes, and obesity. While the negative effects of physical inactivity are widely known, there is a gap between what physicians tell their patients and exercise compliance. Exercise is Medicine was established in 2007 by the American College of Sports Medicine to inform and educate physicians and other health care providers about exercise as well as bridge the widening gap between health care and health fitness. Physicians have many competing demands at the point of care, which often translates into limited time spent counseling patients. The consistent message from all health care providers to their patients should be to start or to continue a regular exercise program. Exercise is Medicine is a solution that enables physicians to support their patients in implementing exercise as part of their disease prevention and treatment strategies.

9.
Int J Yoga ; 11(2): 91-98, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29755216

RESUMO

BACKGROUND: Complementary and alternative medicine is a rapidly growing area of biomedical inquiry. Yoga has emerged in the forefront of holistic medical care due to its long history of linking physical, mental, and spiritual well-being. Research in yoga therapy (YT) has associated improved cardiovascular and quality of life (QoL) outcomes for the special needs of heart failure (HF) patients. AIM: The aim of this study is to review yoga intervention studies on HF patients, discuss proposed mechanisms, and examine yoga's effect on physiological systems that have potential benefits for HF patients. Second, to recommend future research directions to find the most effective delivery methods of yoga to medically stable HF patients. METHODS: The authors conducted a systematic review of the medical literature for RCTs involving HF patients as participants in yoga interventions and for studies utilizing mechanistic theories of stretch and new technologies. We examined physical intensity, mechanistic theories, and the use of the latest technologies. CONCLUSIONS: Based on the review, there is a need to further explore yoga mechanisms and research options for the delivery of YT. Software apps as exergames developed for use at home and community activity centers may minimize health disparities and increase QoL for HF patients.

12.
Percept Mot Skills ; 115(2): 645-60, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23265025

RESUMO

The purpose was to compare 24 participants' acute physiological and affective responses to two aerobic prescriptions in three sessions. Anthropometry, International Physical Activity Questionnaire, and VO2max were recorded. In subsequent visits two aerobic prescriptions were randomly applied: one based on VO2max (PBVO2max) and another based on physical activity level (PBPA). Physiological and affective variables were measured in each session. The PBVO2max showed lower risk for dropout than the PBPA. An effect size analysis showed higher ratings on the Feeling Scale in the PBVO2max session at the end of exercise. After categorizing participants by fitness (High, Medium, and Low) according to VO2max, significant differences were observed for the training impulse between Low and High fitness categories, indicating PBVO2Max were sensitive in distinguishing levels of fitness. The PBVO2max, compared to PBPA, seems to provide better physiological and affective responses. VO2max (even if estimated) is recommended as the basis for aerobic prescriptions.


Assuntos
Afeto/fisiologia , Exercício Físico/fisiologia , Exercício Físico/psicologia , Esforço Físico/fisiologia , Adulto , Antropometria/métodos , Brasil , Teste de Esforço/métodos , Teste de Esforço/psicologia , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Consumo de Oxigênio/fisiologia , Pacientes Desistentes do Tratamento/psicologia , Pacientes Desistentes do Tratamento/estatística & dados numéricos , Risco , Inquéritos e Questionários
13.
Rev. bras. ativ. fís. saúde ; 17(2): 137-142, abr. 12.
Artigo em Português | LILACS | ID: lil-666353

RESUMO

Os objetivos deste estudo foram: estabelecer a prevalência de sobrepeso/obesidade em duas grandes academias no Rio de Janeiro; comparar os resultados com taxas demográficas nacionais e municipais de obesidade; e comparar a prevalência e magnitude de sobrepeso entre os sexos e grupos etários. O estudo analisou 12415 sujeitos (4932 homens e 7483 mulheres) selecionados a partir de um banco de dados de duas academias da cidade do Rio de Janeiro. Após categorização etária (20-29, 30-39, 40-49, 50-59, 60-69 e ? 70 anos), e por índice de massa corporal (IMC) (abaixo do peso e peso normal: < 25 kg/m2, e sobrepeso: ? 25 kg/m2) foram comparadas as prevalências com dados municipais e nacionais, e a prevalência e magnitude de sobrepeso entre sexos e grupos etários. A prevalência de sobrepeso foi maior em homens do que em mulheres. Comparando estes resultados com dados municipais e nacionais, foram encontrados valores de IMC significativamente maiores (p?0,01) para homens (7,7%) e menores para mulheres (21,6%). Uma ANOVA a dois caminhos (idade e sexo) comparando o IMC demonstrou valores significativamente menores para mulheres (21,4±1,8 kg/m2) do que para homens (22,6±1,8 kg/m2) para as classificações abaixo do peso e peso normal, mas não para sobrepeso (28,1±3,1 versus 28,2±3,0 kg/m2, para mulheres e homens respectivamente). Mulheres demonstram prevalência de sobrepeso três vezes menor entre os grupos etários de 20 a 49 anos, assemelhando-se aos homens após 50 anos. Novos estudos são sugeridos com frequentadores de academia para ratificar esses achados, ou verificar possíveis influências regionais e/ou socioeconômicas.


The objectives of this study were: to assess the prevalence of overweight/obesity in two large fitness clubs of the city of Rio de Janeiro, Brazil; to compare its results with municipal and national demographic data; and to compare the prevalence and magnitude of overweight/obesity between genders and age groups. A cross-sectional, retrospective study was conducted with 12,415 subjects (4,932 men and 7,483 women), selected from the database of two fitness clubs of the city of Rio de Janeiro. After age categorization by decade (20-29, 30-39, 40-49, 50-59, 60-69 and ? 70 years) and body mass index (BMI) classification (underweight and normal weight: < 25 kg/m2, and overweight: ? 25 kg/m2), prevalences were compared to municipal and national data. In addition, a comparison of the prevalence and magnitude of overweight was made between sexes and age groups. The prevalence of overweight was higher in men, regardless of age group. Comparing the results with municipal and national data, BMI values were significantly higher (p ?0.01) in men (7.7%) and lower in women (21.6%). The two-way analysis of variance (age and gender) found lower values in women (21.4±1.8 kg/m2), when compared to men (22.6±1.8 kg/m2) in the underweight and normal weight categories, but not in the overweight category (28,1±3,1 versus 28,2±3,0 kg/m2, for women and men respectively). Women showed a 3-fold lower prevalence of overweight in the 20 to 49 year age group, which became similar to that of men after the age of 50 years. New studies are needed to confirm these findings or to identify regional and socioeconomic influences.


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Adulto Jovem , Imagem Corporal , Obesidade/etnologia , Índice de Massa Corporal
15.
J Strength Cond Res ; 26(1): 87-93, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22158136

RESUMO

The objectives were to propose a new strategy for adjusting aerobic training variables based on the eighth American College of Sports Medicine (ACSM) guidelines and maximal aerobic power (&OV0312;O2max) and to establish energy expenditure (EE) recommendations for training, which depend on a subject's body mass (BM). Exclusively based on aerobic training recommendations that are available in the ACSM guidelines, 16 equally partitioned subcategories were created from the slope of a linear regression between the lower (16.4 ml·kg(-1)·min(-1)) and upper (61.2 ml·kg(-1)·min(-1)) limits of VO(2max) percentile tables and all aerobic variables (intensity: 30-85%Reserve, duration: 60-300 min·wk(-1), frequency: 3-5 d·wk(-1), and EE: 1,000-4,000 kcal·wk). ACSM's EE (EE(ACSM)) recommendation was compared to EE based on VO(2max) (EE(Actual)), BM, exercise intensity and duration combined, for five BM categories (60 to 100 kg). The following equations were generated to adjust aerobic training: Intensity (%(Reserve)) = VO(2max) (ml·kg(-1)·min(-1)) × 1.23 + 9.85, Duration (min·wk(-1)) = VO(2max) × 5.36-27.91, Frequency (d·wk(-1) = VO(2max) × 0.044 + 2.27, EE(ACSM) (kcal·wk(-1)) =VO(2max) × 82.61-1,055.29, and EE(Actual) (kcal·wk(-1)) = ([V(O2max) - 3.5] × Intensity + 3.5) × BM (kg)/200 × Frequency. A comparison of EE(ACSM) and EE(Actual) for 5 BM and 3 aerobic fitness categories demonstrated an effect size classification that is equal or superior to "large" in 9 of 15 comparisons, suggesting that EE(ACSM) adjustment is inadequate at least 60% of the time. Despite the need to verify the adequacy of the linear model and perform future cross-sectional and longitudinal studies, the present proposal first provides criteria to adjust aerobic training variables consistent with subject capacity, thus diminishing the risk of the imprecise aerobic prescription.


Assuntos
Exercício Físico , Idoso , Exercício Físico/fisiologia , Feminino , Humanos , Masculino , Consumo de Oxigênio , Educação Física e Treinamento/métodos , Aptidão Física/fisiologia
16.
Curr Sports Med Rep ; 10(6): 383-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22071400

RESUMO

A potential emerging problem associated with increasingly popularized extreme conditioning programs (ECPs) has been identified by the military and civilian communities. That is, there is an apparent disproportionate musculoskeletal injury risk from these demanding programs, particularly for novice participants, resulting in lost duty time, medical treatment, and extensive rehabilitation. This is a significant and costly concern for the military with regard to effectively maintaining operational readiness of the Force. While there are certain recognized positive aspects of ECPs that address a perceived and/or actual unfulfilled conditioning need for many individuals and military units, these programs have limitations and should be considered carefully. Moreover, certain distinctive characteristics of ECPs appear to violate recognized accepted standards for safely and appropriately developing muscular fitness and are not uniformly aligned with established and accepted training doctrine. Accordingly, practical solutions to improve ECP prescription and implementation and reduce injury risk are of paramount importance.


Assuntos
Consenso , Militares , Resistência Física/fisiologia , Aptidão Física/fisiologia , Medicina Esportiva , Traumatismos em Atletas/prevenção & controle , Humanos , Doenças Musculoesqueléticas/prevenção & controle , Segurança/normas
17.
J Am Chem Soc ; 132(39): 13586-7, 2010 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-20828122

RESUMO

Firefly luciferase utilizes the chemical energy of ATP and oxygen to convert its substrate, D-luciferin, into an excited-state oxyluciferin molecule. Relaxation of this molecule to the ground state is responsible for the yellow-green light emission. Synthetic cyclic alkylaminoluciferins that allow robust red-shifted light emission with the modified luciferase Ultra-Glo are described. Overall light emission is higher than that of acyclic alkylaminoluciferins, aminoluciferin, and the native substrate D-luciferin.


Assuntos
Vaga-Lumes/enzimologia , Luciferina de Vaga-Lumes/química , Luz , Luciferases de Vaga-Lume/metabolismo , Substâncias Luminescentes/química , Trifosfato de Adenosina/química , Animais , Benzotiazóis/química , Luciferina de Vaga-Lumes/síntese química , Luciferases de Vaga-Lume/química , Substâncias Luminescentes/síntese química , Estrutura Molecular , Oxigênio/química , Estereoisomerismo , Especificidade por Substrato
18.
Disabil Rehabil ; 32(26): 2172-90, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20718622

RESUMO

UNLABELLED: Autonomic dysreflexia (AD) is unique to individuals with spinal injuries (SCI) at T6 or above and can be voluntarily induced. Although AD improves wheelchair racing performance in some athletes, it also elicits exaggerated blood pressure, which could be dangerous. The International Paralympic Committee considers AD doping and banned its use. PURPOSE: The purpose of this study is to evaluate AD knowledge, incidence and attitudes (KIA) of Paralympians with SCI. METHODS: An existing questionnaire was modified to include questions of AD KIA, validated by three experts and piloted with a small sample. It was administered on-line, mailed to members of a scientific network and distributed during the Beijing Paralympic Games. Fisher Exact test was used to evaluate differences across gender, injury and education. RESULTS: Of 99 participants, 54.5% had previously heard of AD while 39.4% were unaware; 16.7%, all males, had used AD to enhance performance. Participants reported that AD was (1) useful for middle (78.6%) and long distance (71.4%), marathon (64.3%) and wheelchair rugby (64.3%); (2) somewhat dangerous (48.9%), dangerous (21.3%) or very dangerous (25.5%) to health. Results were not influenced by age, injury level or injury duration. CONCLUSIONS: Findings indicate the need for educational programmes directed towards enhancing the AD knowledge of rehabilitation professionals, coaches and trainers working with SCI individuals.


Assuntos
Desempenho Atlético , Disreflexia Autonômica/fisiopatologia , Conhecimentos, Atitudes e Prática em Saúde , Paraplegia/fisiopatologia , Traumatismos da Medula Espinal/fisiopatologia , Esportes , Cadeiras de Rodas , Adolescente , Adulto , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Paraplegia/reabilitação , Projetos Piloto , Traumatismos da Medula Espinal/reabilitação , Inquéritos e Questionários
19.
Med Sci Sports Exerc ; 42(4): 651-7, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19952833

RESUMO

BACKGROUND: The number of African American (AA) patients living with heart failure (HF) has been increasing, especially among the economically disadvantaged. Yoga therapy has been found to improve physical and psychological parameters among healthy individuals, but its effect in patients with HF remains unknown. The purpose of this study was to examine the effects of yoga therapy on cardiovascular endurance (VO2peak), flexibility, quality of life (QoL), and inflammatory markers on medically stable HF patients. METHODS: Forty patients (38 AA, 1 Asian, and 1 Caucasian) with systolic or diastolic HF were randomized to the yoga group (YG, n = 21) or the control group (CG, n = 19). All patients were asked to follow a home walk program. Premeasurement and postmeasurement included a treadmill stress test to peak exertion, flexibility, interleukin-6 (IL-6), C-reactive protein (CRP), and extracellular superoxide dismutase (EC-SOD). QoL was assessed by the Minnesota Living with Heart Failure Questionnaire (MLwHFQ). RESULTS: The statistical analyses (assessed by ANOVA and t-tests) were significant for favorable changes in the YG, compared with those in the CG, for flexibility (P = 0.012), treadmill time (P = 0.002), VO2peak (P = 0.003), and the biomarkers (IL-6, P = 0.004; CRP, P = 0.016; and EC-SOD, P = 0.012). Within the YG, pretest to posttest scores for the total (P = 0.02) and physical subscales (P < 0.001) of the MLwHFQ were improved. CONCLUSIONS: Yoga therapy offered additional benefits to the standard medical care of predominantly AA HF patients by improving cardiovascular endurance, QoL, inflammatory markers, and flexibility.


Assuntos
Negro ou Afro-Americano , Insuficiência Cardíaca/etnologia , Insuficiência Cardíaca/reabilitação , Yoga , Adulto , Idoso , Teste de Esforço , Terapia por Exercício , Feminino , Humanos , Inflamação/sangue , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Inquéritos e Questionários
20.
J Strength Cond Res ; 22(4): 1081-6, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18545204

RESUMO

Creatine monohydrate (CrMH) supplementation aids the ability to maintain performance during repeated bouts of high-intensity exercise, including jump performance. However, carbohydrate supplementation may also provide similar benefits and is less expensive. This study compared the effects of an energy-free placebo, 2 different caloric concentrations of carbohydrate drinks, and a CrMH supplement on repeated jump heights. Sixty active males (mean age, 22 +/- 3.2 years) performed 2 sets of countermovement static jump height tests (10 jumps over 60 seconds) separated by 5 days to determine the differential effects of the placebo, carbohydrate, and CrMH on jump height sustainability over 10 jumps. Subjects were randomly assigned to groups (15 subjects per group) to receive daily doses (x5 days) of carbohydrate drinks containing 100 or 250 kilocalories (kcal), a 25-g CrMH supplement, or an energy-free placebo. After 5 days, the CrMH group experienced a significant weight gain (+1.52; +/-0.89 kg, p < 0.01), while the other groups did not. The 2 levels of carbohydrate and CrMH supplements were all significantly better at sustaining jump height than the energy-free placebo over the final 3-4 jumps. The 250-kcal carbohydrate-supplemented group experienced a level of benefit (p < 0.01) that was at least equal to that of the CrMH group (p < 0.05), suggesting that the higher dose of carbohydrate was as effective as CrMH in maintaining repeated bouts of high-intensity activity as measured by repeated static jumps. Given the equivalent performance improvement and the absence of weight gain, the carbohydrate supplementation could be considered the preferred option for weight-conscious power athletes involved in activities that require repeated- motion high-intensity activities.


Assuntos
Creatina/administração & dosagem , Carboidratos da Dieta/administração & dosagem , Suplementos Nutricionais , Extremidade Inferior/fisiologia , Movimento/efeitos dos fármacos , Adolescente , Adulto , Bebidas , Humanos , Masculino , Movimento/fisiologia , Método Simples-Cego , Aumento de Peso
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