Cardiorespiratory fitness is not associated with risk of venous thromboembolism: a cohort study.

Objectives. The inverse and independent association between cardiorespiratory fitness (CRF) and arterial thrombotic disease is well established. However, the potential association between CRF and venous thromboembolism (VTE) is not well known. We aimed to assess the prospective association of CRF with the risk of VTE. Design. Cardiorespiratory fitness, as measured by maximal oxygen uptake (VO2max), was assessed using a respiratory gas exchange analyser in 2,249 men aged 42-61 years without a history of VTE at baseline in the Kuopio Ischemic Heart Disease prospective cohort. Cox-regression models were used to calculate hazard ratios (HR) with 95% confidence interval (CI) for VTE. We corrected for within-person variability in CRF levels using data from repeat measurements taken several years apart. Results. There were 144 (6.4%) incident VTE events recorded during a median follow-up of 25.2 years. The age-adjusted regression dilution ratio of CRF was 0.58 (95% CI: 0.53-0.64). The risk of VTE did not significantly decrease per 1 standard deviation increase in CRF in age-adjusted analysis (HR 0.90; 95% CI 0.75-1.08). The association remained consistent in analyses adjusted for several established and emerging risk factors (HR 0.90; 95% CI 0.73-1.12). The corresponding adjusted HRs were 0.80 (95% CI: 0.52-1.23) and 0.82 (95% CI: 0.51-1.32) respectively, when comparing the extreme tertiles of CRF levels. Conclusions. In a middle-aged Caucasian male population, CRF was not associated with future risk of VTE. Further studies are required to confirm and to generalize these findings, particulary in women and other age groups.

Effect of ipratropium bromide on EIB in children depends on vagal activity.

PURPOSE: Ipratropium bromide (IB) has been used to prevent exercise-induced bronchoconstriction (EIB), but its effect varies among individuals. We hypothesized that such variability may reflect individual differences in vagal activity (VA), and therefore determined whether a correlation exists between VA and the effect of IB on EIB in 13.0 (+/-0.8)-yr-old children with asthma and documented EIB. METHODS: Subjects served as their own control and were tested on three occasions in an ambient temperature of 5 degrees C. Visit I included no treatment. In visits II and III (counterbalanced sequence) subjects inhaled either 500 microg IB or 0.9% NaCl as a placebo, 45 min before exercise provocation. Investigators and the subjects were blinded to the inhaled substance. VA was assessed by a 4-s exercise test (3). The ratio of resting ECG R-R-interval at full inspiration to the lowest R-R interval during 4-s cycling was taken as an index of VA. Eight-minute cycling at constant work rate (HR=173+/-4 bpm) at 5 degrees C was used to provoke EIB. A two-factor (treatment x time) repeated-measures ANOVA was used. RESULTS: The exercise-induced drop in FEV1 was similar in the three sessions. However, because the IB caused a 15.7+/-4.1 increase in FEV1 preexercise, the postexercise values after a placebo or no treatment were consistently lower than after IB. The beneficial response to IB, compared with no treatment and with placebo, was positively correlated to VA (for FEV1: r=0.91, P=0.002; and r=0.90, P=0.002, respectively). CONCLUSION: We suggest that the therapeutic effect of IB on exercise-induced asthma may be related to vagal activity.

Efeitos do treinamento físico contra resistência sobre a composiçäo corporal e a potência muscular em adultos deficientes de hormônio do crescimento / Effects of physical training against resistance over the corporal composition and the muscular potency in deficient adults of growth hormone

A síndrome de deficiência do hormônio de crescimento (GH) no adulto está bem esclarecida, assim como os benefícios da terapia de reposiçäo com o GH recombinante. Dentre as alteraçöes observadas nesses pacientes, as da composiçäo corporal estäo entre as mais estudadas, sendo caracterizadas por um aumento da gordura corporal total com predomínio de gordura no tronco, diminuiçäo da massa magra, da força muscular e da água corporal total. Todas säo quase completamente revertidas após tratamento de reposiçäo com GH. Estudamos a composiçäo corporal e potência muscular de 11 pacientes com deficiência de GH, antes e após serem submetidos a um programa de treinamento com exercícios contra resistência por 12 semanas, sem reposiçäo com o GH. Avaliamos a composiçäo corporal através de medidas de circunferências, dobras cutâneas, peso, altura, cálculo do índice de massa corporal e relaçäo cintura-quadril. A potência muscular localizada foi avaliada em vários grupos musculares através de cinco exercícios numa unidade de exercícios musculares localizados, onde foi acoplado um tensiômetro. Após análise dos resultados, observamos que näo houve mudança na composiçäo corporal destes pacientes, em relaçäo ao índice de massa corporal, relaçäo cintura-quadril e peso. Quando estudamos separadamente a soma das dobras cutâneas centrais e periféricas, houve diminuiçäo no volume da soma das dobras centrais. Em relaçäo à força e potência muscular, näo houve ganho de força de preensäo manual medida através do dinamômetro (p>0,05), já a potência mostrou um aumento significativo após treinamento (p<0,01). Concluímos que esses pacientes, se submetidos a um programa de treinamento de exercícios contra resistência realizado em casa, ganham potência muscular e que esta forma de exercício é uma alternativa terapêutica para que possam melhorar sua qualidade de vida, quando näo for possível a utilizaçäo do GH.