Five training sessions improves 3000 meter running performance.

AIM: The primary aim of the present study was to evaluate the effect of two weeks of endurance training on 3000-meter running performance. Secondary we wanted to assess the relationship between baseline running performance and change in running performance over the intervention period. METHODS: We assigned 36 military recruits to a training group (N.=28) and a control group. The training group was randomly allocated to one of three sub-groups: 1) a 3000 meter group (test race); 2) a 4x4-minutes high-intensity interval group; 3) a continuous training group. The training group exercised five times over a two-week period. RESULTS: The training group improved its 3000 meter running performance with 50 seconds (6%) compared to the control group (P=0.003). Moreover, all sub-groups improved their performance by 37 to 73 seconds (4-8%) compared to the control group (P<0.037). There was a significant relationship between pretest performance and improvement from pre- to post-test (ρ=-0.65, P<0.001) in the training group. CONCLUSION: We conclude that five endurance training sessions improved 3000 meter running performance and the slowest runners achieved the greatest improvement in running performance.

Early risk factors for pubertal asthma.

BACKGROUND: Early life risk factors are previously described for childhood asthma, but less is known related to asthma in adolescence. We aimed to investigate early risk factors (before 2 years) for pubertal asthma and secondarily for pubertal asthma phenotypes based upon allergic comorbidities. METHODS: Based on data from 550 adolescents in the prospective birth cohort 'Environment and Childhood Asthma' study, subjects were categorized by recurrent bronchial obstruction (rBO) 0-2 years, asthma 2-10 years, and pubertal asthma from 10 to 16 years including incident asthma in puberty and asthma in remission from 10 to 16 years or as never rBO/asthma 0-16 years. Asthma in puberty was further classified based on the comorbidities atopic dermatitis and allergic rhinitis (AR) from 10 to 16 years. Twenty-three common asthma risk factors identified by 2 years of age, including frequency and persistence of bronchial obstruction (severity score), were analysed by weighted logistic regression for each phenotype. RESULTS: In adjusted models, the risk of pubertal asthma increased significantly with higher severity score, parental rhinitis, being the firstborn child, and familial stress around birth. Pubertal asthma in remission was significantly associated with severity score and number of lower respiratory tract infections and inversely associated with breastfeeding beyond 4 months. Pubertal incident asthma was more common among firstborn children. All asthma phenotypes with allergic diseases were significantly associated with severity score, whereas familial perinatal stress increased the risk of asthma only. Asthma combined with AR was associated with parental asthma and being firstborn, whereas the risk of asthma with both atopic dermatitis and AR increased with higher paternal education, atopic dermatitis, being firstborn, and familial perinatal stress. CONCLUSION AND CLINICAL RELEVANCE: Important early risk factors for pubertal asthma were early airways obstruction, parental rhinitis, being the firstborn child, and perinatal familial stress.

Effects of formoterol on endurance performance in athletes at an ambient temperature of -20 degrees C.

The use of inhaled beta2-agonists is restricted in sports. No benefit of inhaled formoterol upon performance was found in healthy athletes under normal climatic conditions, but it has not been investigated whether formoterol improves performance in athletes during exposure to cold. To investigate the effect of inhaled formoterol vs placebo upon performance and lung function at -20 degrees C in 20 healthy male athletes. We used a randomized double-blind, placebo-controlled, cross-over design. The subjects performed a run until exhaustion after inhaled study drug. The speed was 95% of the predetermined maximal oxygen uptake (VO2 max) the first minute and increased to 107% of VO2 max for the remaining part of the test. Time until exhaustion, ventilation (VE), VO2, respiratory rate (RR), tidal volume (VT), heart rate (HR) and arterial oxyhemoglobin saturation (SPO2) were recorded during exercise. Lung function was measured before inhaling, after inhaling the study drug and after the treadmill run. Inhaled formoterol did not improve endurance performance in cold environments compared with placebo, although formoterol significantly improved lung function (FEV1, FEF50 and PEF) and HR 4 min after the start of the exercise. Inhaled formoterol did not improve endurance performance in healthy, well-trained athletes exposed to cold.