Comparison Between Continuous Versus Interval Exercise Training in Asthmatic Patients

Comparison to Short and Medium-term Effects of Continuous and Interval Aerobic Exercise Training in Improving Aerobic Capacity, Psychosocial Factors and Impact on the Level of Physical Activity in Patients With Asthma Moderate and Severe

University of Sao Paulo, Fundação de Amparo à Pesquisa do Estado de São Paulo, Conselho Nacional de Desenvolvimento Científico e Tecnológico

The treatment of asthma is based in clinical control. However, previous studies have been shown that patients that participate of the programs of regular or aerobic continuous exercise training (CT) presented improvements in the physical conditioning, and quality life, as well as decreased the levels of anxiety and depression, reduced the oxide nitric exhaled and leukocyte migration at the airways and reduced the airway hyperresponsiveness. The regular exercise also is important part in the rehabilitation of other lung disease as well as chronic obstructive pulmonary disease (COPD). Additionally, others studies have been shown the effects of high intensity interval training (IT) in the pulmonary rehabilitation of COPD patients, that after performed IT presented reduction of dyspnea, and increase the physical capacity. In this sense, the impact of IT in the asthmatic patients at the present moment is poorly studied, and necessity of the more investigation to prove the efficiency of this training model for asthma patients. .

The present study will compare the impact of IT and CT in patients with moderate or severe asthma, and investigate what is the most efficient and increases the physical capacity, and quality of life and reduces the inflammatory mediators. Sixty asthmatic adults will be randomly assigned into two groups: CT (Continuous training) or IT (Interval training). CT will have treatment 2x week, 40 min./session, 60-75% of maximum heart rate intensity and IT also 2x week, 40 min./session, 80-140% of the maximum load intensity, both performed in ergometer cycle by 24 weeks.

The continuous training (CT) will be held in two weekly sessions lasting total of 40 minutes and 5 minutes for heating and 5 to slowdown, and the duration will be 24 sessions (3 months). The exercise sessions will be will be performed on a stationary bicycle, with the initial intensity of 70% of VO2max. If the subject sustain continuously training intensity for 2 consecutive sessions without symptoms breathing, exercise intensity will be increased by 5% of heart rate. The patient may stop the activity if he has any symptoms or respiratory distress, returning it as soon present improvement. Throughout the training, will be monitored heart rate and the level of perception subjective effort (modified Borg scale).

The interval training (IT) will be held in two weekly sessions. The IT is individualized and will be performed on a stationary bicycle. Training sessions will be performed with total duration of 40 minutes consisting of 5 minutes extender, 30 minutes from the main part (IT), finishing with five minutes back to calm. In the main part (of 5 to 30 minutes), the patient will perform the exercise with high intensity in the first two weeks, the exercise will be conducted with an intensity 80% of maximum capacity obtained in cycle ergometer test and will cycle for 30 seconds followed by a 30 second recovery period. In the 3rd and 4th weeks, the intensity will be increased to 100% of the maximum obtained. After this period, the intensity will be increased by 5% charge.

The education program will discuss issues related to asthma and physical activity. Presentations and group discussions will be carried out, including information about asthma pathophysiology, medication and peak flow meter skills, self-monitoring techniques, environmental control, benefits and current recommendations of physical activity.

Measurements at isotime: at identical work rates before and after training, heart rate, perception exertion and dyspnea.

The level of nitric oxide exhaled (FEno) in the patients with asthma will be quantified with use of the equipment Niox Mino (Niox, Solna, Sweden).

The levels of inflammatory mediators interleukin (IL)-4, IL-5, IL-6, IL-8, IL-2, IL-12, IL-17, Interferon gamma (IFN-γ), Tumor necrosis factor alpha (TNF-α), IL-10, and chemokines IL-8, Regulated on Activation, Normal T cell Expressed and Secreted (RANTES), Monocyte Chemoattractant Protein-1 (MCP-1), Monokine induced by gamma interferon (MIG), Interferon gamma-induced protein-10 (IP-10) e Transforming Growing Factor-beta (TGF-b) in the serum will be analyzed by Cytometric bead array (CBA) technique (BD Biosciences, San Jose, California, EUA).

The level plasmatic of cortisol hormone will be quantified by fluoroimmunoassay by AutoDelfia (Turku, Finland).

The level of Physical activity will be analyzed using a pedometer Yamax model PW 610 (Yamasa, Japan) during 7 consecutive days.

Inclusion Criteria: Asthma moderate and severe Asthma will diagnosed (Global Initiative for Asthma - GINA) Body Mass Index (BMI) < 35kg/m2 Medical Treatment for at least 6 months Clinically stable (i.e., no exacerbation or medication changes for at least 30 days) Exclusion Criteria: Cardiovascular, musculoskeletal or other different chronic lung diseases Active cancer Pregnant Smokers