Evaluation of Physical Activity in Asthmatic Subjects

Asthma is a chronic disease, which leads to a number of adverse outcomes, including possible lower levels of physical activity (PA). Physical inactivity is an important risk factor, it and was shown that training improves cardiopulmonary fitness, symptoms and quality of life. Increasing PA has become a patient-centred goal for the treatment of subjects with asthma.

Data provided by activity monitors are commonly used to measure daily PA. For PA assessments using an accelerometer, recordings of at least 4 weekly days with a minimum of 8 hours of monitor use (during waking hours) are recommended. A recent systematic review showed that adults with asthma had lower levels of total, moderate and vigorous physical activity than those without asthma. Physical activity appears to be influenced by comorbidities such as obesity in addition to age and sex, decreased disease control, and increased severity. Ather authors involved obese subjects with asthma assigned to a 12-month lifestyle intervention dually targeted modest weight loss (achieve and maintain a weight loss of 7% of baseline body weight) and increased physical activity (achieve and maintain a minimum of 150 minutes per week of moderate intensity physical activity) compared with usual care (control group). Moderately and severely obese adults with uncontrolled asthma showed modest average weight reduction and PA improvements. Finally was showed that a comprehensive pulmonary rehabilitation (PR) program including a weight loss program and exercise training improves PA in moderately-severely obese adults with asthma.

There are no data showing the possible effects of a PR program on PA (number of daily steps) in normal-weight subjects with asthma.

The main objective of this pilot study is to obtain estimates of the mean value (and standard deviation) of number of daily steps, time spent on activity in hours and of other variables in normal-weight subjects with asthma measured before and after the PR program. No estimates about these parameters in the same population are currently available from literature search. This information will be used for formal sample size calculations when planning a future larger study investigating the number of daily steps and time in activity of normal-weight subjects with asthma before and after PR.

Inclusion criteria

• diagnosis of asthma according to GINA step 3-5
• body mass index (BMI) between 18.5 and 24.9 kg/m2
• under optimal medical treatment for at least 3 months according to GINA guideline
• able to perform and complete with studies procedures.

Exclusion criteria

• diagnosis of any other chronic pulmonary disease
• smokers or ex-smokers with pack/years ≥10
• acute exacerbation of asthma in the last 30 days
• engagement in exercise training program in the previous 6 months
• history of significant oncological, neurological, cardiovascular diseases
• musculoskeletal impairment
• medical diseases that are likely to compromise mobility and precluding exercise testing and PR
• use of a walker when moving
• reduced spontaneous gait speed (10 m walk test< at 0.8 m/sec).