Inspiratory Muscle Training in Children and Adolescents With Idiopathic Scoliosis Undergoing Schroth Therapy.

Assessment of pulmonary ventilation will be performed using pulmonary function testing with a MasterScreen Pneumo spirometer (Jaeger). This examination is non-invasive and performed in accordance with ATS and ERS criteria.

The data collected for analysis will include the following parameters: vital capacity (VC), forced vital capacity (FVC), forced expiratory volume in one second (FEV1), peak expiratory flow (PEF), maximal expiratory flow at 50% of forced vital capacity (MEF50).

Unite of measurements: all measurements are taken as a percentage from predicted.

Pulmonary function test will be performed using a MasterScreen Pneumo spirometer (Jaeger). This examination is non-invasive and performed in accordance with ATS and ERS criteria.

Maximal inspiratory flow at 50% of FVC (MIF50) is expressed in litres per second (l/s).

Pulmonary function test will be performed using a MasterScreen Pneumo spirometer (Jaeger). This examination is non-invasive and performed in accordance with ATS and ERS criteria.

The MEF50/MIF50 ratio is a dimensionless value (because in this case the MEF50 value is expressed in l/s, similarly to MIF50). This indicator assesses airway patency. It is mainly used for the diagnosis and differentiation of upper airway stenosis.

Respiratory muscle strength will be assessed by measuring maximal inspiratory and expiratory pressure. The test is non-invasive and will be performed using a pneumatic adapter connected to the tachometer of the device used for pulmonary function testing. The assessment will be conducted in accordance with ATS/ERS guidelines; following the recommended procedure, 5 to 10 measurements will be taken, from which the three highest values will be selected.

Based on the results of this test, the training parameters for the planned intervention will be determined.

To provide information on the mechanical and elastic properties of the respiratory system, the forced oscillation technique (FOT) will be performed. For this purpose, the Resmon Pro V3 device (MGC Diagnostics®) will be used, employing the built-in pediatric mode that applies an 8 Hz signal frequency. The main parameters analyzed will be resistance (Rrs) and reactance (Xrs).

This test will be used to assess cardiorespiratory fitness. The examination will be conducted in accordance with the American Thoracic Society guidelines for this test. The parameter analyzed will be the distance covered by the participants.

Isokinetic dynamometry using the Biodex Multi-Joint System will be employed to assess the participants' ability to maintain postural stability in different planes under static and isokinetic conditions.

Assessed muscle groups responsible for trunk stabilization: trunk flexors (abdominal muscles) and trunk extensors (back muscles).

The evaluated parameter, peak torque, represents the maximum recorded torque produced by the analyzed muscle group at a specified angular velocity, expressed in newton-meters (N·m).

Measurements will consist of performing trunk flexion and extension as quickly as possible with maximal force at two angular velocities. A warm-up will be conducted prior to testing. Five maximal trials will be performed, with rest periods between trials. During the trials, participants will be verbally encouraged to exert maximal effort.

Isokinetic dynamometry using the Biodex Multi-Joint System will be employed to assess the participants' ability to maintain postural stability in different planes under static and isokinetic conditions.

Assessed muscle groups responsible for trunk stabilization: trunk flexors (abdominal muscles) and trunk extensors (back muscles).

Total work is the work performed by the muscles throughout all movements executed during the task. It also allows for the assessment of muscle endurance. This parameter is expressed in joules (J).

Measurements will consist of performing trunk flexion and extension as quickly as possible with maximal force at two angular velocities. A warm-up will be conducted prior to testing. Five maximal trials will be performed, with rest periods between trials. During the trials, participants will be verbally encouraged to exert maximal effort.

Isokinetic dynamometry using the Biodex Multi-Joint System will be employed to assess the participants' ability to maintain postural stability in different planes under static and isokinetic conditions.

Assessed muscle groups responsible for trunk stabilization: trunk flexors (abdominal muscles) and trunk extensors (back muscles).

Average power is a parameter calculated by dividing the work performed during a single repetition by the duration of the movement. Its values are expressed in watts (W).

Measurements will consist of performing trunk flexion and extension as quickly as possible with maximal force at two angular velocities. A warm-up will be conducted prior to testing. Five maximal trials will be performed, with rest periods between trials. During the trials, participants will be verbally encouraged to exert maximal effort.

Physical activity levels will be assessed using the PAQ-C (Physical Activity Questionnaire for Children) or PAQ-A (Physical Activity Questionnaire for Adolescents). This questionnaire gathers information on the frequency and intensity of physical activities, including sports, outdoor play, and other forms of exercise. Higher scores indicate greater levels of physical activity.