"Inspiratory Muscle Training in Older Women"

Overview

Objective: To evaluate the effectiveness of two protocols of inspiratory muscle training (IMT) in older women to improve respiratory strength, spirometric parameters and dyspnea. Low-intensity vs high-intensity resistance training programs. Evaluations: Determination of the maximum inspiratory pressure (MIP) and the maximum expiratory pressure (MEP); spirometry - maximum voluntary ventilation (MVV), peak expiratory flow (PEF), tidal volume (TV); functional capacity measured with 6 minute walk test; dyspnea using the Borg scale and clinical evaluations. The participants will be evaluated at the beginning and end of the intervention period. Intervention: There are two groups of patients, one works with low loads (20% MIP) and another with high loads (40% MIP). They train 5 days/week 15 cycles lasting 1 minute. There is a rest of 1 minute between each cycle.

Participants: Institutionalized women will be recruited to participate in an 8-week randomized trial. All patients will be asked to carry out the 5-day weekly program, and a recording sheet will be provided to each participant so they will can record the time of each daily respiratory training session. All participants signed an informed consent form. The patients will be assigned to the two groups randomly. The main researcher doesn´t meet any of the participants until the initial assessment will be carried out. Evaluation: The participants are evaluated at the beginning and end of the intervention period. The evaluation of MIP and MEP is performed using a pressure transducer, Elka 15, which obtains each measurement in millibar and converts it into the reference unit of centimeter of water (cm H2O) (1 mbar = 1.01973 cm H2O .), following the rules of the American thoracic society/European respiratory society (ATS / ERS). The procedure will be repeated until 3 values were obtained with a difference of less than 5%, and the highest value will be used for the analysis. The MIP of the intervention group will be assessed every 2 weeks to set the IMT workload. Lung volumes are assessed using a spirometer (model: datospir touch) with a turbine transducer with a maximum flow of 16 l/s and a maximum volume of 10 l. The ATS/ERS rules will be followed \[19\], and the highest value of three correct measurements will be chosen. Data is collected for the following parameters: maximum voluntary ventilation (MVV), forced expiratory volume in the first second (FEV1), peak expiratory flow (PEF), mean expiratory flow (FEF25-75), vital capacity (VC), tidal volume (TV) and forced vital capacity (FVC). Dyspnea will be measured using the modified Borg scale \[20\]. Functional capacity will be measured with 6 minute walk test. All evaluations will be done in the corresponding center, during the same time slot and by the same examiner for both groups. Intervention: "High-intensity group". The device incorporates a unidirectional valve independent of flow to guarantee constant resistance and includes a specific pressure setting (in cm H2O). The intensity of the device will be 40% of MIP. The protocol includes 15 cycles lasting 1 minute, twice a day: one in the morning and one in the afternoon. The participants rest for 1 minute between each cycle. In total, the protocol includes 30 minutes of daily respiratory training. The patients will be instructed to inhale with enough force to reach the opening of the valve. "Low-intensity group".The device incorporates a unidirectional valve independent of flow to guarantee constant resistance and includes a specific pressure setting (in cm H2O). The intensity of the device will be 20% of MIP. The protocol includes 15 cycles lasting 1 minute, twice a day: one in the morning and one in the afternoon. The participants rest for 1 minute between each cycle. In total, the protocol includes 30 minutes of daily respiratory training. The patients will be instructed to inhale with enough force to reach the opening of the valve.