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1.
Psychophysiology ; 59(11): e14090, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35599295

RESUMO

Although well-evidenced in older adults, the effects of exercise on the hippocampus in youth are relatively unknown. This study examined the impact of a 6-month school-based physical activity intervention on hippocampal metabolism in adolescents using magnetic resonance spectroscopy. A subset of lower fit older adolescents [N = 56, 61% female, 16.1 ± 0.4 years] was included from four secondary schools (10 classes) in New South Wales, Australia, who were participating in a larger cluster randomized controlled trial. Participants were randomized to the Burn 2 Learn (B2L) intervention (five classes, 30 participants) or a control group (five classes, 26 participants). Changes in hippocampal metabolism were assessed using linear mixed models adjusted for clustering at the class level. We observed group-by-time effects for the B2L intervention on N-acetylaspartate (NAA) (+2.66 mmol/L, 95% CI 0.20 to 5.11, d = 0.66) and glutamate+glutamine (Glx) (+3.38 mmol/L, 95% CI 0.34 to 6.42, d = 0.67) in the left hippocampus. Increases in left hippocampal NAA and Glx concentrations were associated with improvements in cardiorespiratory fitness (NAA: rs  = 0.52, p = .016; Glx: rs  = 0.57, p = .007), lower body muscular fitness (NAA: rs  = 0.49, p = .018; Glx: rs  = 0.59, p = .003), and working memory (NAA: rs  = 0.42, p = .032; Glx: rs  = 0.43, p = .028) in the intervention group. Our findings suggest physical activity may improve hippocampal metabolism in lower fit older adolescents with implications for working memory. Further studies involving larger samples are needed to replicate our findings.


Assuntos
Treinamento Intervalado de Alta Intensidade , Adolescente , Idoso , Feminino , Glutamatos/metabolismo , Glutamina/metabolismo , Hipocampo , Humanos , Espectroscopia de Ressonância Magnética/métodos , Masculino
2.
Environ Res ; 212(Pt A): 113152, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35341754

RESUMO

Mercury distribution and bioaccumulation in aquatic ecosystems of tropical Australia is poorly characterised. Barramundi (Lates calcarifer), a widespread high-order predator in both fresh and coastal marine waters of the region, fulfils requirements for a bio-indicator of mercury contamination. In a study of the Mary River system of the Northern Territory, total mercury in the muscle tissue of 300 specimens gathered over four years (2013-2017, across both wet and dry seasons) was determined by direct combustion-atomic absorption spectrometry. Source of nutrition and trophic position of barramundi in the food web was also estimated via carbon and nitrogen isotopes (δ13C and δ15N), respectively, in tissue by stable isotope mass spectrometry, and determination of strontium isotopes (87Sr/86Sr) in otoliths by laser ablation-ICPMS differentiated between freshwater and saltwater residence. Results showed that fish moving into freshwater floodplain wetlands concentrated mercury in muscle tissue at approximately twice the level of those that remained in saline habitats. Resolving life histories through otolith analyses demonstrated diversity in mercury bioaccumulation for individual fish of the same migratory contingent on the floodplains. Although trophic level (δ15N), capture location, source of nutrition (δ13C), and age or size partly predicted mercury concentrations in barramundi, our results suggest that individual variability in diets, migration patterns and potentially metabolism are also influential. Using a migratory fish as a bio-indicator, and tracking its life history and use of resources, proved valuable as a tool to discern hot spots in a coastal waterway for a contaminant, such as mercury.


Assuntos
Características de História de Vida , Mercúrio , Perciformes , Poluentes Químicos da Água , Animais , Bioacumulação , Ecossistema , Monitoramento Ambiental , Peixes/metabolismo , Cadeia Alimentar , Mercúrio/análise , Isótopos de Nitrogênio/análise , Perciformes/metabolismo , Poluentes Químicos da Água/análise
3.
Scand J Med Sci Sports ; 29(3): 469-475, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30468537

RESUMO

Training and competition loads have emerged as valuable injury risk factors but very few studies have explored injury outcomes in adolescent athletes. The aims of this study were to describe injuries and to explore the relationship between training and match load volumes and injury in adolescent athletes participating in multiple contact team sports. One hundred and three male youth rugby athletes aged 14-16 years from 8 rugby union teams were prospectively monitored during a season for weekly training and match volumes and injuries. The relationship between volume and injury was explored by comparing the weekly volume in the week prior to an injury vs weeks without injury. There were 83 time-loss injuries in 58 athletes (62%). Overall injury incidence was 18.5 per 1000 player-hours. Mean weekly injury prevalence was 27% (95% CI 25-30). Average weekly volume was 5.4 (2.2) hours comprising 1.4 (1) match hours and 4 (2.6) training hours. Compared with weeks without injury, weeks prior to an injury had higher match volumes (110 [57] min vs 83 [59] min, P < 0.001). Poisson regression demonstrated that match volume was a predictor of injury with an odds ratio of 1.41 (P = 0.001). The contribution of match volumes to injury risk and the relatively high injury burden in these athletes may be profound. Very high match volumes are unlikely to be in the best interests of young athletes and could be avoided with a systematic approach to load management and athlete development.


Assuntos
Traumatismos em Atletas/epidemiologia , Futebol Americano/lesões , Carga de Trabalho , Adolescente , Humanos , Incidência , Masculino , Condicionamento Físico Humano , Prevalência , Estudos Prospectivos , Fatores de Risco
4.
Int J Sports Physiol Perform ; 14(5): 620-626, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30427236

RESUMO

Purpose: To examine the collective independent influence of a range of individual characteristics on physical and technical match performance during international rugby sevens matches. Methods: Data were collected from 20 international rugby sevens players from 1 team across 1 season. Activity profiles were measured using wearable microtechnology devices, and technical performance measures were collected from match video analysis. Subjective well-being measures were collected using a well-being questionnaire completed on the morning of main training days, and groin-squeeze assessments at 0° and 60° knee flexion were also conducted using a sphygmomanometer. Assessments of aerobic fitness were completed periodically across the season, including time to complete a 2-km run and final velocity during the 30:15 Intermittent Fitness Test (VIFT). A principal-components analysis was conducted to reduce the dimensionality of the physical and technical variables into single-factor values. Linear mixed models were then constructed to examine the collective influence of a range of individual contextual variables on physical and technical performance factors. Results: Increased muscle soreness, stress, and VIFT were associated with trivial to small increases in physical and technical performance values, whereas trivial to small decreases were associated with higher perceived recovery, body weight, and groin squeeze (0° knee flexion). Conclusions: A range of well-being metrics are required to account for a significant portion of the variance in physical and technical performance. These factors may be manipulated by coaches or practitioners to achieve favorable physiological readiness that may lead to improved match performance.


Assuntos
Desempenho Atlético , Futebol Americano , Adulto , Aptidão Cardiorrespiratória , Comportamento Competitivo , Humanos , Modelos Lineares , Estudos Longitudinais , Microtecnologia/instrumentação , Análise de Componente Principal , Estudos Prospectivos , Inquéritos e Questionários , Dispositivos Eletrônicos Vestíveis , Adulto Jovem
5.
Breast Care (Basel) ; 13(5): 369-372, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30498424

RESUMO

INTRODUCTION: Oncotype DX® analyses the expression of 21 genes within tumour tissue to determine a Recurrence Score® (RS). RS is a marker of risk for distant recurrence in oestrogen receptor-positive early breast cancer, allowing patient-specific benefit of chemotherapy to be evaluated. Our aim was to determine whether the introduction of Oncotype DX led to a net reduction in chemotherapy use. METHODS: Consecutive patients that underwent Oncotype DX at Warwick Hospital were reviewed. Patients were anonymised and re-discussed at a multidisciplinary team meeting (MDM; without RS), and treatment recommendations were recorded. This was compared to the original MDM outcome (recommendations made with RS). Differences were analysed using Wilcoxon signed-rank test. RESULTS: 67 patients were identified. Proportions of high, intermediate and low risk were 28, 33 and 39% (n = 19/22/26), respectively. Without RS, 56 (84%) patients were recommended for chemotherapy and 3 were not. The remaining 8 patients were deemed borderline for requiring chemotherapy and referred for discussion with an oncologist. With availability of RS, 34 (50%) patients were recommended for chemotherapy, and 24 (43%) patients were spared chemotherapy (p < 0.0005). The net reduction in chemotherapy was 33%. CONCLUSION: There has been a significant reduction in chemotherapy usage in patients at Warwick since the introduction of Oncotype DX.

6.
J Strength Cond Res ; 32(10): 2762-2769, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28723812

RESUMO

Harries, SK, Lubans, DR, Buxton, A, MacDougall, THJ, and Callister, R. Effects of 12-week resistance training on sprint and jump performances in competitive adolescent rugby union players. J Strength Cond Res 32(10): 2762-2769, 2018-Sprint performance is an important characteristic for success in many sports, including rugby union. Resistance training is used to increase muscular fitness (i.e., strength, endurance, and power) and may also be effective for improving sprint and jump performances. The aims of this study were to examine the effects of resistance training using 2 different periodized programs (linear and daily undulating) on sprint and jump performances and explore relationships between performance measures. Sixteen male (16.9 ± 1.0 years) adolescent rugby union players participated in 12 weeks of resistance training. A further 10 male (15.5 ± 1.0 years) participants were recruited as a control group. Assessments of strength (box squat), 10- and 20-m sprint (electronically timed), and jump height (maximal unloaded (body mass only) and loaded (body mass + 10 kg) countermovement jumps) were conducted before and after 12 weeks training. Large to very large increases in 1 repetition maximum box squat (linear: 33.9%; p < 0.001; effect size (ES) = 1.64; daily undulating: 44.5%; p < 0.001; ES = 2.33) were observed after training. Small decreases were seen in 10-m (linear: -1.6%; p = 0.171; ES = -0.84; daily undulating: -2.5%; p = 0.038; ES = -0.36) and 20-m (linear: -0.5%; p = 0.506; ES = -0.20; daily undulating: -1.7%; p = 0.047; ES = -0.27) sprint times. Small-to-moderate associations between changes in lower-body strength and improvements in 10- and 20-m sprint times were found. Resistance training increases lower-body strength in adolescent rugby union players and increases in lower-body strength may transfer to improved sprinting performance with improvements after daily undulating periodized resistance training slightly superior.


Assuntos
Desempenho Atlético/fisiologia , Força Muscular , Treinamento Resistido/métodos , Adolescente , Teste de Esforço , Futebol Americano/fisiologia , Humanos , Masculino , Corrida/fisiologia
7.
PLoS One ; 12(4): e0174762, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28403149

RESUMO

BACKGROUND: Biomarkers have been used extensively to provide the connection between external levels of contaminant exposure, internal levels of tissue contamination, and early adverse effects in organisms. OBJECTIVES: To present a three-step protocol for identifying suitable biomarkers to assess fish health in coastal and marine ecosystems, using Gladstone Harbour (Australia) as a case study. METHODS: Prior to applying our protocol, clear working definitions for biomarkers were developed to ensure consistency with the global literature on fish health assessment. First, contaminants of concern were identified based on the presence of point and diffuse sources of pollution and available monitoring data for the ecosystem of interest. Second, suitable fish species were identified using fisheries dependent and independent data, and prioritised based on potential pathways of exposure to the contaminants of concern. Finally, a systematic and critical literature review was conducted on the use of biomarkers to assess the health of fish exposed to the contaminants of concern. RESULTS/DISCUSSION: We present clear working definitions for bioaccumulation markers, biomarkers of exposure, biomarkers of effect and biomarkers of susceptibility. Based on emission and concentration information, seven metals were identified as contaminants of concern for Gladstone Harbour. Twenty out of 232 fish species were abundant enough to be potentially suitable for biomarker studies; five of these were prioritised based on potential pathways of exposure and susceptibility to metals. The literature search on biomarkers yielded 5,035 articles, of which 151met the inclusion criteria. Based on our review, the most suitable biomarkers include bioaccumulation markers, biomarkers of exposure (CYP1A, EROD, SOD, LPOX, HSP, MT, DNA strand breaks, micronuclei, apoptosis), and biomarkers of effect (histopathology, TAG:ST). CONCLUSION: Our protocol outlines a clear pathway to identify suitable biomarkers to assess fish health in coastal and marine ecosystems, which can be applied to biomarker studies in aquatic ecosystems around the world.


Assuntos
Doenças dos Peixes/diagnóstico , Doenças dos Peixes/metabolismo , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/metabolismo , Proteínas de Peixes/metabolismo , Peixes , Estresse Oxidativo , Revisões Sistemáticas como Assunto , Poluentes Químicos da Água/metabolismo , Qualidade da Água
8.
Gland Surg ; 6(6): 682-688, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29302486

RESUMO

BACKGROUND: The last two decades have seen significant changes in surgical management of breast cancer. The offer of immediate breast reconstruction (IBR) following mastectomy is currently standard practice. Skin sparing and nipple sparing mastectomy with implant-based IBR have emerged as oncologically safe treatment options. Prepectoral implant placement and complete coverage of implant with acellular dermal matrix (ADM) eliminates the need to detach the muscle from underlying chest wall in contrast to the subpectoral technique. We report short-term outcomes of a multicentre study from the United Kingdom (UK) using Braxon® in women having an IBR. METHODS: A prospective study was conducted from December 2015 to October 2016 and included all patients from three breast units in the UK who underwent a mastectomy and an implant-based IBR using Braxon®. The demographic details, co-morbidities, operative details, immediate and delayed complications were recorded. Specific complications recorded were infection, seroma, unplanned readmission and loss of implant. A comparison was made with complications reported in the National Mastectomy and Reconstruction Audit. RESULTS: Seventy-eight IBRs were included in the analysis with a median follow-up of 9.98 months. Mean age of the cohort was 50 years with a mean body mass index of 25.7 kg/m2. Mean implant volume was 365 cc. The inpatient hospital stay was 1.48 days. About 23% of patients had a seroma, 30% had erythema requiring antibiotics and the explant rate was 10.2 percent. Bilateral reconstructions were significantly associated with implant loss and peri-operative complications on univariate analysis. CONCLUSIONS: Our early experience with this novel prepectoral technique using Braxon® has shown it to be an effective technique with complication rates comparable to subpectoral IBR. The advantages of prepectoral implant-based IBR are quicker postoperative recovery and short post-operative hospital stay. Long-term studies are required to assess rippling, post-operative animation, capsular contracture and impact of radiotherapy.

9.
Nutrients ; 8(9)2016 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-27618089

RESUMO

OBJECTIVES: The aims of the current study were to comprehensively assess the dietary intakes and diet quality of a sample of Australian competitive adolescent rugby union players and compare these intakes with National and Sports Dietitians Association (SDA) Recommendations for adolescent athletes. A secondary aim investigated applying different physical activity level (PAL) coefficients to determine total energy expenditure (TEE) in order to more effectively evaluate the adequacy of energy intakes. DESIGN: Cross-sectional. METHODS: Anthropometrics and dietary intakes were assessed in 25 competitive adolescent male rugby union players (14 to 18 years old). Diet was assessed using the validated Australian Eating Survey (AES) food frequency questionnaire and diet quality was assessed through the Australian Recommended Food Score. RESULTS: The median dietary intakes of participants met national recommendations for percent energy (% E) from carbohydrate, protein and total fat, but not carbohydrate intake when evaluated as g/day as proposed in SDA guidelines. Median intakes of fibre and micronutrients including calcium and iron also met national recommendations. Overall diet quality was classified as 'good' with a median diet quality score of 34 (out of a possible 73); however, there was a lack of variety within key food groups including carbohydrates and proteins. Non-core food consumption exceeded recommended levels at 38% of the daily total energy intake, with substantial contributions from takeaway foods and sweetened beverages. A PAL coefficient of 1.2-1.4 was found to best balance the energy intakes of these players in their pre-season. CONCLUSIONS: Adolescent rugby players met the percent energy recommendations for macronutrients and attained an overall 'good' diet quality score. However, it was identified that when compared to specific recommendations for athletes, carbohydrate intakes were below recommendations and these players in their pre-season reported high consumption of non-core foods, particularly sugar sweetened drinks and low intakes of vegetables.


Assuntos
Dieta Saudável , Metabolismo Energético , Exercício Físico , Fenômenos Fisiológicos da Nutrição Esportiva , Adolescente , Austrália , Estudos Transversais , Carboidratos da Dieta/administração & dosagem , Gorduras na Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Água Potável/administração & dosagem , Ingestão de Energia , Futebol Americano , Humanos , Masculino , Micronutrientes/administração & dosagem , Avaliação Nutricional , Política Nutricional , Recomendações Nutricionais , Inquéritos e Questionários
10.
Mar Pollut Bull ; 112(1-2): 427-435, 2016 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-27423445

RESUMO

A need exists for appropriate tools to evaluate risk and monitor potential effects of contaminants in tropical marine environments, as currently impact assessments are conducted by non-representative approaches. Here, a novel bioassay is presented that allows for the estimation of the chronic toxicity of contaminants in receiving tropical marine environments. The bioassay is conducted using planktonic larvae of the barnacle Amphibalanus amphitrite and is targeted at generating environmentally relevant, chronic toxicity data for water quality guideline derivation or compliance testing. The developmental endpoint demonstrated a consistently high control performance, validated through the use of copper as a reference toxicant. In addition, the biological effects of aluminium, gallium and molybdenum were assessed. The endpoint expressed high sensitivity to copper and moderate sensitivity to aluminium, whereas gallium and molybdenum exhibited no discernible effects, even at high concentrations, providing valuable information on the toxicity of these elements in tropical marine waters.


Assuntos
Alumínio/toxicidade , Bioensaio/métodos , Thoracica/efeitos dos fármacos , Animais , Cobre/toxicidade , Gálio/toxicidade , Larva/efeitos dos fármacos , Molibdênio/toxicidade , Controle de Qualidade , Reprodutibilidade dos Testes , Qualidade da Água
11.
Breast Dis ; 36(1): 23-6, 2016 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-27177340

RESUMO

INTRODUCTION: Assessment of the sentinel lymph node biopsy (SLNB) is used to stage the axilla in patients with breast cancer. There are a variety of methods to assess metastatic disease within the SLN. One-step nucleic acid amplification (OSNA) has a high sensitivity for detecting metastatic disease within the SLN and avoids the use of staged axillary surgery. However there remains a paucity of data within the literature on the psychological effects upon patients with the use of OSNA. METHODS: All patients undergoing breast surgery (breast-conserving surgery or mastectomy) and assessment of the SLNB with OSNA from December 2011 to June 2012 were included in the study. A questionnaire was sent to patient within four weeks of surgery to assess their understanding and satisfaction with the OSNA procedure. RESULTS: 60 patients responded to the questionnaire (83% response rate). All patients were female with a mean age of 63 years (range 38-71 years). 19 patients had positive SLNB as assessed by OSNA and all had ALND. 15 patients expressed pre-operative anxiety about having OSNA although 97% stated that they would be happy to undergo the same procedure again. CONCLUSION: Our study has identified the anxiety points that patients experience with OSNA based management and this will allow improved direct emotional support and provision of information.


Assuntos
Ansiedade/psicologia , Neoplasias da Mama/psicologia , Técnicas de Amplificação de Ácido Nucleico/métodos , Linfonodo Sentinela/metabolismo , Adulto , Idoso , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Feminino , Humanos , Metástase Linfática , Mastectomia , Mastectomia Segmentar , Pessoa de Meia-Idade , Estadiamento de Neoplasias/métodos , Estadiamento de Neoplasias/psicologia , Satisfação do Paciente , Linfonodo Sentinela/patologia , Biópsia de Linfonodo Sentinela , Inquéritos e Questionários
12.
Orthop J Sports Med ; 4(3): 2325967116634075, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27069947

RESUMO

BACKGROUND: Rugby union is a collision-based ball sport played at the professional level internationally. Rugby union has one of the highest reported incidences of injury of all team sports. PURPOSE: To identify the characteristics, incidence, and severity of injuries occurring in Australian professional Super Rugby Union. DESIGN: Descriptive epidemiology study. METHODS: The present study was a prospective epidemiology study on a cohort of 180 professional players from 5 Australian Super Rugby teams during the 2014 Super Rugby Union Tournament. Team medical staff collected and submitted daily training and match-play injury data through a secure, web-based electronic platform. The injury data included the main anatomic location of the injury, specific anatomic structure of the injury, injury diagnosis, training or match injury occurrence, main player position, mechanism of injury, and the severity of the injury quantified based on the number of days lost from training and/or competition due to injury. RESULTS: The total combined incidence rate for injury during training and match-play across all Australian Super Rugby Union teams was 6.96 per 1000 hours, with a mean injury severity of 37.45 days lost from training and competition. The match-play injury incidence rate was 66.07 per 1000 hours, with a mean severity of 39.80 days lost from training and competition. No significant differences were observed between forward- and back-playing positions for match or training injury incidence rate or severity. CONCLUSION: The incidence of injury for the present study was lower during match-play than has previously been reported in professional rugby union; however, the overall time loss was higher compared with previous studies in professional rugby union. The high overall time loss was due fundamentally to a high incidence of injuries with greater than 28 days' severity.

13.
J Sci Med Sport ; 19(2): 163-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25709054

RESUMO

OBJECTIVES: To determine changes in maximal strength between two different resistance training progression models, linear (LP) and daily undulating (DUP), over a 12-week resistance training programme in sub-elite adolescent rugby union players. DESIGN: The study used a quasi-experimental study design. Following baseline assessments, participants from Squad 1 were randomised to either LP or DUP; participants from Squad 2 formed a non-randomised comparison group (CON). METHODS: Participants were 26 sub-elite adolescent rugby union players who were assessed at baseline and after 12 weeks. Outcomes included 5 repetition maximum (RM) box squat and bench press, height, body weight, skeletal muscle mass, percentage body fat and maturation status. RESULTS: Participants in both the LP and DUP groups significantly increased their squat and bench press strength from baseline to 12 weeks. There were no significant differences between groups for squat and bench press increases after 12 weeks (p>0.05). No significant increases in squat or bench press strength were observed after 12 weeks in the CON group. Increases in lower body strength were large in the LP group (ES: 1.64) and very large in the DUP group (ES: 2.33). Upper body strength changes were small in both groups (LP, ES: 0.57; DUP, ES: 0.31). CONCLUSIONS: Twelve weeks of LP or DUP resistance training are both effective at increasing maximal lower and upper body strength in adolescent rugby athletes. Additionally, twice weekly frequency of resistance training in adolescent rugby athletes with greater than 6-months resistance training experience is sufficient to elicit substantial increases in maximal strength.


Assuntos
Desempenho Atlético/fisiologia , Futebol Americano/fisiologia , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Treinamento Resistido/métodos , Adolescente , Humanos , Masculino
14.
Breast Care (Basel) ; 10(1): 39-43, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25960724

RESUMO

BACKGROUND: This study assessed the views of patients undergoing breast surgery for breast cancer with a planned overnight stay, asking whether they would be happy to be discharged home on the same day of surgery. METHODS: A structured questionnaire sent out in the 6 weeks following surgery was used to ascertain the patients' views. RESULTS: The majority of patients undergoing mastectomy and axillary node clearance preferred an overnight stay, primarily for psychological reasons. CONCLUSIONS: Patients undergoing breast-conserving surgery were more prepared to go home on the day of surgery.

15.
J Strength Cond Res ; 29(4): 1113-25, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25268290

RESUMO

Periodization is known to improve training adaptations but the most effective periodization approach for muscular strength development for a wide variety of populations is yet to be determined. This systematic review and meta-analysis examined all studies directly comparing linear and undulating periodized resistance training programs to determine and compare their effects on muscular strength. A systematic search of the MEDLINE, SCOPUS, and SPORTDiscus databases revealed 17 studies satisfying the inclusion criteria. There were a total of 510 participants in the included studies. Sixteen studies reported significant increases in strength for both periodization approaches. Five studies reported significant differences in improvements between groups. The meta-analyses determined that there were no differences in the effectiveness of linear vs. undulating periodization on upper-body or lower-body strength. The short-term nature of studies and the previous training history of participants were identified as potential confounding factors in the interpretation of findings. The results suggest that novelty or training variety are important for stimulating further strength development. Few studies have examined the effect of periodization approaches in adolescent or athletic populations.


Assuntos
Força Muscular , Músculo Esquelético/fisiologia , Treinamento Resistido/métodos , Adaptação Fisiológica , Adolescente , Humanos
16.
J Sci Med Sport ; 18(1): 72-6, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24388353

RESUMO

OBJECTIVES: The study aim was to assess rater agreement of the Resistance Training Skills Battery (RTSB) for adolescents. The RTSB provides an assessment of resistance training skill competency and includes six exercises. The RTSB can be used to assess performance and progress in adolescent resistance training programmes and to provide associated feedback to participants. Individual skill scores are based on the number of performance criteria successfully demonstrated and an overall resistance training skill quotient (RTSQ) is created by summing the six skill scores. DESIGN/METHODS: The eight raters had varying experience in movement skill assessment and resistance training and completed a 2-3h training session in how to assess resistance training performance using the RTSB. The raters then completed an assessment on six skills for 12 adolescents (mean age=15.1 years, SD=1.0, six male and six female) in a randomised order. RESULTS: Agreement between seven of the eight raters was high (20 of the 21 pairwise correlations were greater than 0.7 and 13 of the 21 were greater than 0.8). Correlations between the eighth rater and each of the other seven raters were generally lower (0.45-0.78). Most variation in the assigned RTSB scores (67%) was between cases, a relatively small amount of the variation (10%) was between raters and the remainder (23%) was between periods within raters. The between-raters coefficient of variation was approximately 5%. CONCLUSIONS: The RTSB can be used reliably by those with experience in movement skill assessment and resistance training to assess the resistance skill of adolescents.


Assuntos
Teste de Esforço , Destreza Motora , Aptidão Física , Treinamento Resistido , Adolescente , Feminino , Humanos , Masculino , Variações Dependentes do Observador , Reprodutibilidade dos Testes
17.
J Strength Cond Res ; 28(5): 1373-80, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24755868

RESUMO

The aim of this study was to describe the development and assess test-retest reliability and construct validity of the Resistance Training Skills Battery (RTSB) for adolescents. The RTSB provides an assessment of resistance training skill competency and includes 6 exercises (i.e., body weight squat, push-up, lunge, suspended row, standing overhead press, and front support with chest touches). Scoring for each skill is based on the number of performance criteria successfully demonstrated. An overall resistance training skill quotient (RTSQ) is created by adding participants' scores for the 6 skills. Participants (44 boys and 19 girls, mean age = 14.5 ± 1.2 years) completed the RTSB on 2 occasions separated by 7 days. Participants also completed the following fitness tests, which were used to create a muscular fitness score (MFS): handgrip strength, timed push-up, and standing long jump tests. Intraclass correlation (ICC), paired samples t-tests, and typical error were used to assess test-retest reliability. To assess construct validity, gender and RTSQ were entered into a regression model predicting MFS. The rank order repeatability of the RTSQ was high (ICC = 0.88). The model explained 39% of the variance in MFS (p ≤ 0.001) and RTSQ (r = 0.40, p ≤ 0.001) was a significant predictor. This study has demonstrated the construct validity and test-retest reliability of the RTSB in a sample of adolescents. The RTSB can reliably rank participants in regards to their resistance training competency and has the necessary sensitivity to detect small changes in resistance training skill proficiency.


Assuntos
Teste de Esforço , Treinamento Resistido , Levantamento de Peso/fisiologia , Adolescente , Feminino , Força da Mão/fisiologia , Humanos , Masculino , Destreza Motora/fisiologia , Reprodutibilidade dos Testes
18.
Congenit Heart Dis ; 9(4): E110-2, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-23701826

RESUMO

Bland-White-Garland syndrome, also known as anomalous origin of the left coronary artery from the pulmonary artery, is a rare congenital disorder affecting around one in 300,000 live births. The majority of these present within the first year of life with 90% mortality rate if untreated and consequently is an extremely rare presentation in the adult. We present the first published case with a left dominant system in an adult presenting in their late 20s, illustrated by multimodality imaging.


Assuntos
Síndrome de Bland-White-Garland/diagnóstico , Circulação Colateral , Angiografia Coronária/métodos , Circulação Coronária , Vasos Coronários , Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X , Adulto , Síndrome de Bland-White-Garland/diagnóstico por imagem , Síndrome de Bland-White-Garland/patologia , Síndrome de Bland-White-Garland/fisiopatologia , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/patologia , Vasos Coronários/fisiopatologia , Humanos , Masculino , Imagem Multimodal , Valor Preditivo dos Testes , Disfunção Ventricular Esquerda/diagnóstico , Disfunção Ventricular Esquerda/fisiopatologia , Função Ventricular Esquerda , Remodelação Ventricular
19.
J Sci Med Sport ; 15(6): 532-40, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22541990

RESUMO

OBJECTIVES: Resistance training in untrained adolescents can positively effect health-related fitness as well as improve muscular power and sports performance. The impact of resistance training on adolescent athletes is less clear. The purpose of this review is to determine the effectiveness of resistance training programs on muscular power and sports performance in adolescent athletes. DESIGN: Systematic review and meta-analysis of previously published studies investigating resistance training in adolescent athlete populations. METHODS: A systematic search of Medline, Embase, and SPORTDiscus databases was conducted on 21st March 2011 to identify studies evaluating resistance training programs on power and sports performance in adolescent athletes. RESULTS: Thirty-four studies were identified. All but two of the studies reported at least one statistically significant improvement in an alactic muscular power outcome. The most common indicators of alactic power were vertical jump (25 studies) and sprint running (13 studies) performance. Fourteen studies provided data to allow for pooling of results in a meta-analysis. A positive effect was detected for resistance training programs on vertical jump performance (mean difference 3.08 [95% CI 1.65, 4.51], Z=4.23 [P<0.0001]). CONCLUSIONS: There is sufficient evidence to conclude that resistance-training interventions can improve muscular power in adolescent athletes. A positive effect on sports performance attributable to participation in resistance training was reported by almost half the included studies, however limited objective evidence to support these claims was found. Improvements in motor performance skills, such as jumping, are widely stated as indicators of improvements in sporting performance.


Assuntos
Atletas , Desempenho Atlético/fisiologia , Força Muscular/fisiologia , Treinamento Resistido , Adolescente , Feminino , Humanos , Masculino , Destreza Motora/fisiologia , Corrida/fisiologia , Resultado do Tratamento
20.
Am J Kidney Dis ; 47(5): e67-72, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16632009

RESUMO

Posttransplantation lymphoproliferative disorder (PTLD) is one of the most serious complications of solid-organ transplantation. It potentially is treatable in most cases, but current methods involve withdrawal or reduction of immunosuppression and the consequent risk for graft rejection. Sirolimus was shown in vivo and in vitro to limit proliferation of a number of malignant cell lines, including those of PTLD-derived cells. We present a case of disseminated PTLD in a patient with a renal transplant that resolved completely with conversion of immunosuppression to sirolimus. Graft function was maintained and improved with treatment. This offers a novel means of treating these patients and minimizing transplant loss.


Assuntos
Imunossupressores/uso terapêutico , Transplante de Rim/efeitos adversos , Transtornos Linfoproliferativos/tratamento farmacológico , Transtornos Linfoproliferativos/etiologia , Sirolimo/uso terapêutico , Adulto , Humanos , Transtornos Linfoproliferativos/patologia , Masculino , Indução de Remissão
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