Injury related risk behavior - a study of Australian skydivers

Risk taking behaviour has been identified as an important host-related determinant of injury in young adults. The aim of this study is to clarify the relationship between the two key elements of risk taking behaviour - ie, risk assessment and risk acceptance - in participants of a high risk sporting activity. Skydivers registered with the Australian Parachute Federation were sampled at several jump meetings held at three 'drop-zones' in North Eastern Australia. A cross sectional survey of 215 skydivers ascertained each subject's risk assessment of each of nine hypothetical sky diving scenes and whether or not they would jump in the described conditions. Variables which independently predicted an individual's risk assessment were age group (p < 0.05), gender (p < 0.05) and scene details (p < 0.001). Risk assessment was found to be a statistically significant predictor of the decision to jump, with a 22% decrease in the odds of jumping with every unit increase in risk assessment (OR = 0.78: 95% Cl; 0.76, 0.80). Gender was also found to be a statistically significant predictor of the decision to jump, with males being 19% more likely to jump than females, after controlling for age, experience, currency and risk assessment (OR = 1.19: 95% CI; 1.04, 1.38). The importance of these results is that, by quantifying the relationship between two key elements of risk taking behaviour and several important host factor determinants, they facilitate more informed discussion about the possible role of risk taking behaviour in the causation of injury.

Alterações da força de preensão em portadores de polineuropatia amiloidótica familiar

Introdução: A polineuropatia amiloidótica familiar (PAF) é uma doença autossómica dominante neurodegenerativa relacionada com a deposição sistémica de fibras de amiloide essencialmente a nível do sistema nervoso periférico. Clinicamente, caracteriza-se por uma neuropatia sensitivo-motora iniciando-se quase sempre nos membros inferiores e comprometendo subsequentemente as mãos. Até agora, o único tratamento conhecido com efeitos positivos no atrasar da progressão da doença é o transplante hepático com medicação com efeitos negativos para o metabolismo muscular e consequentemente para a capacidade de produção de força. Do nosso conhecimento, não existem caracterizações quantitativas dos níveis de força nestes indivíduos nem comparações com a população saudável. Este conhecimento seria extremamente importante para verificar a evolução clínica e funcional desta doença e para a eventual prescrição adequada de um programa de reabilitação. Objectivo: O objectivo deste estudo foi descrever e comparar os níveis de força de preensão (peak force) entre doentes PAF com ou sem transplante de fígado (PAFTx e PAFNTx, respectivamente) com um grupo de indivíduos saudáveis (GC). Material e métodos: A amostra total foi constituída por 206 indivíduos, divididos em três grupos: 59 indivíduos PAFNTx (23 homens, 36 mulheres; idade 35 ± 8 anos); 85 indivíduos PAFTx (52 homens, 33 mulheres; idade 34 ± 8 anos) e 62 GC (30 homens, 32 mulheres; idade 33 ± 9 anos). A força de preensão foi avaliada com um dinamómetro de preensão portátil E-Link (Biometrics Ltd, UK). Tanto as posições de medição como as ordens fornecidas foram estandardizadas. O valor de força máxima considerado foi classificado de acordo com as normas do American College of Sports Medicine (ACSM) para a força de preensão. Resultados: Os três grupos são diferentes (p < 0,05) no peso, no IMC e na força de preensão em ambas as mãos, bem como na resistência da mão esquerda. Foram encontradas correlações negativas entre a força e a idade, para os grupos PAFNTx e PAFTx, mas não para o grupo GC. Conclusões: De acordo com os nossos resultados, os indivíduos portadores de PAF apresentaram valores mais baixos para a força de preensão em ambas as mãos do que os indivíduos aparentemente saudáveis e consequentemente uma pior classificação nas normas do ACSM. A maioria dos doentes apresenta valores de força de preensão abaixo da média ou mesmo precária. Estes resultados poderão mostrar as implicações negativas na funcionalidade destes indivíduos e indicam também a necessidade de um programa de reabilitação com especificidade ao nível da motricidade da mão.

Comparison of body fat content and distribution of familial amyloidotic polyneuropathy patients versus healthy subjects

The deposition of amyloid fibers at the peripheral nervous system can induce motor neuropathy in Familial Amiloidotic Polyneuropethy (FAP) patients. This produces progressive reductions in functional capacity. The only treatment for FAP is a liver transplant, followed by aggressive medication that can affect patients' metabolism. To our knowledge, there are no data on body fat distribution or comparison between healthy and FAP subjects, which may be important for clinical assessment and management of this disease.

Effects of a randomized trial of exercise on body composition of liver transplanted patients

Liver transplantation is used as a only therapy so far, that stop the progression of some aspects of familial amyloidotic polyneuropathy disease (FAP) an autossomic neurodegenerative disease. FAP often results in severe functional limitations. Transplantation requires aggressive medication which impairs bone and muscle metabolism. Malnutrition plus weight loss is already one feature of FAP patients. All this may produce negative consequences on body composition. The effect of exercise training in FAP patients after a liver transplant (FAPTX) is currently unknown. The purpose of this study is to evaluate the effects of a six months exercise training program on body composition in FAPTX patients.

Relationship of balance to function independence in stroke survivors

Cerebral vascular disease is the primary cause of permanent disability in Portugal. Impaired stability is considered an important feature after stroke as it is related with higher risk of falls and functional dependence. Physiotherapy intervention usually starts early after stroke in order to direct motor recovery and help patients to improve their ability to perform activities of daily living (ADL). Purpose: to investigate the relationship of balance to functionality in acute stroke patients. Methods: 16 subjects (8 women and 8 men), mean age 63,62 ± 2,16y, with unilateral ischemic stroke in the middle cerebral artery territory, who were admitted to physiotherapy department of Fernando Fonseca Hospital in Portugal, within the first month after stroke were recruited to participate in this study. All subjects have no cognitive impairment according to Mini Mental State, no history of lower extremity orthopedic problems and no other disease that could interfere with treatments. All patients gave their inform consent to participate in this study. Subjects were assessed with the Modified Barthel Index (MBI) and the Berg Balance Scale (BBS).

Actividade física na criança com asma brônquica

Devido à sua prevalência, a asma brônquica (AB) é uma das patologias respiratórias mais frequente na nossa população. É de igual modo a doença crónica mais comum nas crianças. Outrora, a prática de qualquer actividade física era desaconselhada a crianças com AB. Hoje sabe-se que a actividade física pode ser um dos meios terapêuticos para controlar esta doença. São objectivos deste artigo reforçar a importância do exercício na criança asmática e dos benefícios desse mesmo exercício, não minimizando a asma induzida pelo exercício; evidenciar as linhas orientadoras do exercício segundo o American College of Sports Medicine (modalidades/tipo, frequência, intensidade, duração e condições especiais) para esta população; contribuir para diminuir os medos relativos à actividade física em crianças asmáticas presentes nos pais das crianças com asma e nas próprias crianças.

Crioterapia como tratamento de entorses de tornozelos de atletas: revisão sistemática

A crioterapia é prática comum na medicina esportiva, pela praticidade, facilidade de acesso e baixo custo, possuindo vantajoso uso na Saúde Pública. No entanto, os efeitos analgésicos do gelo tem pouca base objetiva e sistematizada em termos de técnicas, duração e frequência. O objetivo deste estudo foi sintetizar através da revisão sistemática (RS) as evidências relativas à efetividade da crioterapia para o tratamento das entorses de tornozelo de atletas. A RS é um método de pesquisa observacional e retrospectivo, pelo qual se tratam artigos, preferencialmente Ensaios Clínicos Aleatórios – ECA, como sujeitos da investigação, com rigorosos critérios de inclusão e exclusão e, quando possível, realiza-se uma macro estatística dos resultados – metaanálise. No presente RS, foram consultados cinco bancos de dados - Medline, Embase, Cochrane, Lilacs e PEDro para buscar ECA sobre crioterapia com os desfechos dor, edema, rigidez e função. Resultados: 289 estudos foram identificados inicialmente, dos quais nove com tratamentos isolados ou associados à crioterapia, porém apenas um preencheu aos critérios de inclusão, cujo N era 121 atletas, dos quais 64 receberam a crioterapia (funcional) e 57 no grupo controle (imobilização). Maior probabilidade para o evento dor foi observada no grupo controle, após 3 e 12 meses. A RS revelou uma lacuna em ECA dentro do tema, mas não encontrou efeito adverso na prática da crioterapia, sendo um princípio analgésico importante, sobretudo em lesões de tecidos moles.

Sciatic Nerve High Division: Two Different Anatomical Variants

Introduction: Sciatic nerve variations are relatively common. These variations are often very significant in several fields of Medicine. The purpose of this paper is to present two such variants and discuss their clinical implications. Material and Methods: Three Caucasian cadavers with no prior history of lower limb trauma or surgery were dissected and found to present anatomical variants of the sciatic nerve. Results: In all cases the sciatic nerve divided above the popliteal fossa. In two cases (cadavers 1 and 2) it divided on both sides in the inferior portion of the gluteal region in its two terminal branches: the common fibular and the tibial nerves. In another case (cadaver 3) the sciatic nerve was found to divide inside the pelvis just before coursing the greater sciatic notch. The common fibular nerve exited the pelvis above the pyriformis muscle and then passed along its posterior aspect, while the tibial nerve coursed deep to the pyriformis muscle. Discussion: According to the literature, the anatomical variant described in cadaver 3 is considered relatively rare. This variant can predispose to nerve entrapment and thus to the pyriformis syndrome, sciatica and coccygodynia. The high division of the sciatic nerve, as presented in cadavers 1 and 2, can make popliteal nerve blocks partially ineffective. Conclusion: The anatomical variants associated with a high division of the sciatic nerve, must always be born in mind, as they are relatively prevalent, and have important clinical implications, namely in Anesthesiology, Neurology, Sports Medicine and Surgery.

ACL injuries identifiable for pre-participation imagiological analysis: Risk factors

Identification of pre-participation risk factors for noncontact anterior cruciate ligament (ACL) injuries has been attracting a great deal of interest in the sports medicine and traumatology communities. Appropriate methods that enable predicting which patients could benefit from pre- ventive strategies are most welcome. This would enable athlete-specific training and conditioning or tailored equipment in order to develop appropriate strategies to reduce incidence of injury. In order to accomplish these goals, the ideal system should be able to assess both anatomic and functional features. Complementarily, the screening method must be cost-effective and suited for widespread application. Anatomic study protocol requiring only standard X rays could answer some of such demands. Dynamic MRI/CT evaluation and electronically assisted pivot-shift evaluation can be powerful tools providing complementary information. These upcoming insights, when validated and properly combined, envision changing pre-participation knee examination in the near future. Herein different methods (validated or under research) aiming to improve the capacity to identify persons/athletes with higher risk for ACL injury are overviewed. 

Efeito do treinamento físico de membros superiores aeróbio de curta duração no deficiente físico com hipertensão leve

OBJETIVO: Verificar as alterações provocadas pelo treinamento físico (TF), com membros superiores (MMSS), em condição aeróbia de curta duração, sobre variáveis dos sistemas cardiovascular e metabólico. MÉTODOS: Foram estudados 11 deficientes físicos (DF) paraplégicos, com média de idade de 59 anos, sendo 7 homens e 4 mulheres, com lesão de T9 a T11 e grau leve de hipertensão arterial sistêmica (HAS). Os DF foram avaliados antes e após 12 semanas de um programa de TF supervisionado de MMSS, por meio de teste ergométrico (TE) em cicloergômetro mecânico adaptado para MMSS, utilizando-se protocolo intermitente com incremento de carga de 125kgm/min (20w) para mulheres e 140kgm/min (25w) para homens a cada 3min., em velocidade que variou de 83 a 95rpm. O consumo de oxigênio (VO2) foi calculado de acordo com a equação para MMSS do American College of Sports Medicine. A intensidade do exercício durante o programa de TF foi estabelecida pela reserva de freqüência cardíaca (RFC) de Karvonen, com variação de 65% a 85% e escala de percepção subjetiva ao esforço de Borg obtida pelo TE. RESULTADOS: A capacidade aeróbia máxima estimada aumentou 22% (930±349 vs 1138±290mL/min; p=0,003); a pressão arterial sistólica (PAS) e diastólica (PAD) em repouso e no exercício submáximo diminuíram em 4%, 15% e 5%, 5%, respectivamente. CONCLUSÃO: O TF aeróbio de intensidade leve a moderada com MMSS, além de melhorar a aptidão funcional exerce também papel importante como modelo terapêutico não medicamentoso na resposta hipertensiva observada em DF paraplégicos.

A new proposal to guide velocity and inclination in the ramp protocol for the treadmill ergometer

OBJECTIVE: To suggest criteria to guide protocol prescription in ramp treadmill testing, according to sex and age, based on velocity, inclination, and max VO2 reached by the population studied. METHODS: Prospective study describing heart rate (HR), time, velocity, inclination, and VO2 estimated at maximum effort of 1840 individuals from 4 to 79 years old, who performed a treadmill test (TT) according to the ramp protocol. A paired Student t test was used to assess the difference between predicted and reached max VO2, calculated according to the formulas of the "American College of Sports Medicine". RESULTS: Submaximal HR was surpassed in 90.1% of the examinations, with a mean time of 10.0±2.0 minute. Initial and peak inclination velocity of the exercise and max VO2 were inversely proportional to age and were greater in male patients. Predicted Max VO2 was significantly lower than that reached in all patients, except for female children and adolescents (age < 20 years old). CONCLUSION: Use of velocity, inclination, and maximum VO2 actually reached, as a criterion in prescribing the ramp protocol may help in the performance of exercise in treadmill testing. The ramp protocol was well accepted in all age groups and sexes with exercise time within the programmed 8 to 12 minutes.

Detection of testosterone administration based on the carbon isotope ratio profiling of endogenous steroids: international reference populations of professional soccer players.

BACKGROUND AND OBJECTIVES: The determination of the carbon isotope ratio in androgen metabolites has been previously shown to be a reliable, direct method to detect testosterone misuse in the context of antidoping testing. Here, the variability in the 13C/12C ratios in urinary steroids in a widely heterogeneous cohort of professional soccer players residing in different countries (Argentina, Italy, Japan, South Africa, Switzerland and Uganda) is examined. METHODS: Carbon isotope ratios of selected androgens in urine specimens were determined using gas chromatography/combustion/isotope ratio mass spectrometry (GC-C-IRMS). RESULTS: Urinary steroids in Italian and Swiss populations were found to be enriched in 13C relative to other groups, reflecting higher consumption of C3 plants in these two countries. Importantly, detection criteria based on the difference in the carbon isotope ratio of androsterone and pregnanediol for each population were found to be well below the established threshold value for positive cases. CONCLUSIONS: The results obtained with the tested diet groups highlight the importance of adapting the criteria if one wishes to increase the sensitivity of exogenous testosterone detection. In addition, confirmatory tests might be rendered more efficient by combining isotope ratio mass spectrometry with refined interpretation criteria for positivity and subject-based profiling of steroids.

Changes in Running Mechanics and Spring-Mass Behaviour during a 5-km Time Trial

Research into the biomechanical manifestation of fatigue during exhaustive runs is increasingly popular but additional understanding of the adaptation of the spring-mass behaviour during the course of strenuous, self-paced exercises continues to be a challenge in order to develop optimized training and injury prevention programs. This study investigated continuous changes in running mechanics and spring-mass behaviour during a 5-km run. 12 competitive triathletes performed a 5-km running time trial (mean performance: 17 min 30 s) on a 200 m indoor track. Vertical and anterior-posterior ground reaction forces were measured every 200 m by a 5-m long force platform system, and used to determine spring-mass model characteristics. After a fast start, running velocity progressively decreased (- 11.6%; P<0.001) in the middle part of the race before an end spurt in the final 400-600 m. Stride length (- 7.4%; P<0.001) and frequency (- 4.1%; P=0.001) decreased over the 25 laps, while contact time (+ 8.9%; P<0.001) and total stride duration (+ 4.1%; P<0.001) progressively lengthened. Peak vertical forces (- 2.0%; P<0.01) and leg compression (- 4.3%; P<0.05), but not centre of mass vertical displacement (+ 3.2%; P>0.05), decreased with time. As a result, vertical stiffness decreased (- 6.0%; P<0.001) during the run, whereas leg stiffness changes were not significant (+ 1.3%; P>0.05). Spring-mass behaviour progressively changes during a 5-km time trial towards deteriorated vertical stiffness, which alters impact and force production characteristics.

Skeletal Muscle Mitochondrial and Lipid Droplet Volume Density: Validity of Electron Microscopy Point-counting Measurements

Mitochondrial (M) and lipid droplet (L) volume density (vd) are often used in exercise research. Vd is the volume of muscle occupied by M and L. The means of calculating these percents are accomplished by applying a grid to a 2D image taken with transmission electron microscopy; however, it is not known which grid best predicts these values. PURPOSE: To determine the grid with the least variability of Mvd and Lvd in human skeletal muscle. METHODS: Muscle biopsies were taken from vastus lateralis of 10 healthy adults, trained (N=6) and untrained (N=4). Samples of 5-10mg were fixed in 2.5% glutaraldehyde and embedded in EPON. Longitudinal sections of 60 nm were cut and 20 images were taken at random at 33,000x magnification. Vd was calculated as the number of times M or L touched two intersecting grid lines (called a point) divided by the total number of points using 3 different sizes of grids with squares of 1000x1000nm sides (corresponding to 1µm2), 500x500nm (0.25µm2) and 250x250nm (0.0625µm2). Statistics included coefficient of variation (CV), 1 way-BS ANOVA and spearman correlations. RESULTS: Mean age was 67 ± 4 yo, mean VO2peak 2.29 ± 0.70 L/min and mean BMI 25.1 ± 3.7 kg/m2. Mean Mvd was 6.39% ± 0.71 for the 1000nm squares, 6.01% ± 0.70 for the 500nm and 6.37% ± 0.80 for the 250nm. Lvd was 1.28% ± 0.03 for the 1000nm, 1.41% ± 0.02 for the 500nm and 1.38% ± 0.02 for the 250nm. The mean CV of the three grids was 6.65% ±1.15 for Mvd with no significant differences between grids (P>0.05). Mean CV for Lvd was 13.83% ± 3.51, with a significant difference between the 1000nm squares and the two other grids (P<0.05). The 500nm squares grid showed the least variability between subjects. Mvd showed a positive correlation with VO2peak (r = 0.89, p < 0.05) but not with weight, height, or age. No correlations were found with Lvd. CONCLUSION: Different size grids have different variability in assessing skeletal muscle Mvd and Lvd. The grid size of 500x500nm (240 points) was more reliable than 1000x1000nm (56 points). 250x250nm (1023 points) did not show better reliability compared with the 500x500nm, but was more time consuming. Thus, choosing a grid with square size of 500x500nm seems the best option. This is particularly relevant as most grids used in the literature are either 100 points or 400 points without clear information on their square size.