## 2 Materials and Methods
### Evaluation Protocol  
To standardize the electromyographic (EMG) data, each muscle underwent maximal voluntary isometric contraction (MVIC). We recorded the EMG signal amplitude during these contractions. While the test postures mirrored those found in standard physical therapy manuals for muscle testing, we applied additional manual resistance to the back muscles. This progressive manual pressure was gradually increased to a maximum and held for five seconds. With a 30-s rest period between each repetition, each muscle was tested three times. Additionally, we checked the accuracy of electrode placement by scrutinizing the EMG amplitudes during these tests. Specifically, to assess the erector spinase muscles, we stabilized the participant's lower limbs while they performed maximal prone trunk extension, with resistance applied to the upper thoracic region [8; 20]. Furthermore, the placement of the EMG electrodes was performed according to the guidelines provided by the SENIAM [21].  
The exercises were performed in a controlled environment with adequate space and a non-slip surface. Each participant underwent an initial assessment to tailor the exercise to their specific scoliosis curve. The participant was seated with the spine in a neutral position. Participants then started the exercise by extending their spines. This involves lengthening the torso, focusing on creating space between the vertebrae. During the extension phase, the correct breathing technique is emphasized with inhalation from the convex side to the concave side following the corrective symmetric body position. The participant performs specific movements aimed at spinal de-rotation, side shifting in central position, and keeping neutral kypholordosis. This included lateral shifting, rotational movements or shoulder and pelvic adjustments until a symmetric body position was maintained. Throughout the exercise, the participant practiced scoliosis-specific 3-dimensional exercise-specific breathing and correction techniques. All three exercise types included elongation from caudal to cranial with neutral lumbar lordosis, thoracic kyphosis and fixed neck chin in position, breathing and self-correction directed from the convex side to the concave side of the body to facilitate de-rotation against the gibposity side in the transverse plane. The side shifted from the convex side to the concave side in the frontal plane, and neutral and relaxed thoracic kyphosis and lumbar lordosis was maintained in the sagittal plane. All of this 3D protocol was then applied with manual resistance using hand rhythmic stimulation on the concave side (Figure 1A) and with self-resistance from the concave side to the convex side on participants with a TheraBand. In this position, the participant tries to pull himself into a symmetric position against resistance from a TheraBand (Figure 1B), with the TheraBand chosen based on OMNI-RES scores for each participant [22], and the other group used just breathing and self-correction (Figure 1C). To eliminate the learning effect and ensure randomization, each participant performed the exercises in a random order. In order to lessen the effects of tiredness, rest intervals of 30 s were permitted between each exercise repeat, and a minute-long break was provided between workouts.