Effectiveness of a Nordic Walking in Patients With Asthma.

A parallel group, randomized controlled trial to compare the effectiveness of an eight-week Nordic walking program plus three educational sessions and usual care in contrast to three educational sessions and usual care in patients with asthma.

The researchers hypothesize that Nordic walking program plus educational sessions and usual care is superior to educational sessions and usual care in terms of exercise tolerance, physical activity, asthma and symptoms control, dyspnea, lung function, handgrip strength, quality of life, quality of sleep, rate of medication intake, treatment adherence, and healthcare use in patients with asthma

Sample size was calculated considering a minimum clinically important difference (MCID) of 26 meters and a standard deviation of 45.49 meters. With a power of 80%, an alpha level of 0.05 and supposing a dropout rate of 15%, a total of 114 patients, 57 in each group, are required.

Patients will be recruited from Pulmonology and Allergology services of University Hospital Complex of A Coruña, Pulmonology service of HM Modelo Hospital (A Coruña) and primary care centres in Coruña.

Nordic walking and educational sessions will be conducted in A Coruña city. Exercise tolerance, physical activity, asthma and symptoms control, dyspnea, lung function, handgrip strength, quality of life, quality of sleep, rate of medication intake, treatment adherence, and healthcare use will be measured at baseline, and then at two (post-intervention), three and six months. Respiratory muscle strength will be measure at baseline to characterize the sample. Any adverse effect occurring during evaluation or intervention will be recorded and analysed.

Data distribution will be check with Kolmogorov-Smirnov test. Quantitative data will be expressed as mean and standard deviation when normally distributed and as a median and quartiles (Q1-Q3) when no normally distributed. To compare outcomes between Nordic walking group (NWG) and control group (CG), it will be calculated an ANOVA test for repeated measures or a Kruskal-Wallis test.

Also, qualitative analysis will be made to get information about NWG experience: the way to deal with the disease, satisfaction with the intervention given, perceived progress in management of disease after intervention. Qualitative information will be collected from focus groups. The interview will be recorded, transcript, and re-read by two of the investigators to generate codes and, afterwards, themes. These themes will be named and defined. Absolut and relative frequencies will be analysed from each theme. Inter-rate agreement will be measured through agreement percentages calculated as number of thematic units in which evaluators agree divided by total number of units; and through Kappa of Cohen, considering \>0.81 almost a perfect agreement.

Eligibility Criteria:
Inclusion Criteria:

* Being ≥18 years old.
* Present an asthma diagnosis.
* People that desires participate in the study.
* People able to sign the informed consent.

Exclusion Criteria:

* People with other respiratory pathologies.
* Smokers.
* Asthma exacerbation in the last four weeks.
* Heart failure in the last six months.
* Cardiac arrhythmia with IIIb or superior grade in Lown scale.
* Respiratory infection in the last four weeks.
* Gait disorders that impaired the Nordic walking activity.
* Comorbidities that entail reduced exercise capacity: significant anaemia, electrolyte imbalance, or hyperthyroidism.
* People that follow training sessions of more than 30 minutes per day with a moderate or vigorous intensity.
* People that have followed in last three months a pulmonary rehabilitation program.
* Pregnant and lactating women.
* People meeting exclusion criteria to perform cardiovascular exercise following American Heart Association (AHA).
* People meeting exclusion criteria for 6MWT following ATS/ERS criteria