Impact of Pilates Method on Myofascial Stiffness, Cardiorespiratory Fitness and Quality of Life in Breast Cancer Women

The effectiveness of breast cancer treatment is quite well documented. Still, side effects can underpin other treatment-induced diseases such as osteopenia, diabetes, and especially cardiovascular dysfunction. Therefore, finding a method that could partly counteract these side effects and at the same time be implemented throughout treatment is a challenge for researchers.

The main purpose of this experimental, randomized control trial was to analyze the effect of the Pilates Method (PM) intervention on changing the myofascial stiffness along the thoracic and lumbar spine, cardiorespiratory fitness and quality of life in women with breast cancer receiving aromatase inhibitor therapy. The apllied procedure of 12 -week PM training included the training intervention based on hypothesis:

* PM reduces myofascial stiffness along the thoracic and lumbar spine of women with breast cancer receiving aromatase inhibitor therapy
* PM improves the cardiorespiratory fitness of women with breast cancer receiving aromatase inhibitor therapy
* PM improves the quality of life of women with breast cancer receiving aromatase inhibitor therapy.

Possible practical applications include the domains of exercise medicine, physical activity in cancer and public health.

The trial was conducted by Poznan University of Physical Education in cooperation with UMP (Poland).

This design of trial assumed the parallel two-arm group, prospective, randomized controlled trial (RCT) comparing an exercises-based intervention (experimental group) to usual care and physical activity recommendation (control group) in women with breast cancer with perioperative hormonal treatment AI.Randomization were performed as a simple randomization with a 1:1 allocation (coin toss).

All patients were assessed and recruited by two oncologists regarding eligibility to participate in the study.

Before enrollment, all participants were given detailed information about experiment, procedures, risks, and benefits of the study and gave their written consent to participation. The patients were informed at any stage of the project may resign from participation without having to give a reason.The study was conducted in two stages. Patient recruitment and data collection started in February 2022. The baseline assessment of patients is carried out two weeks before the start of PT intervention. PT intervention lasted 12 weeks. Post-intervention assessment is performed during two weeks after PT intervention. Finally data (reports) collection and data preparation for analysis were completed in December 2023.

Potential patients matching primary criteria underwent clinical, laboratory, EKG and echocardiographic follow-up assessment by cardiologist. Clinical specialists eligible for the study provided information about the study and presented informed consent to patients. The patients were referred for further study diagnostics after clinical qualification and signed written informed consent to the planned research.

Together with oncologists the research group also included sports physiologists, cardiologist, certified Pilates teacher. All participants were evaluated by same qualified personnel according to standardized test protocols and in the same conditions at baseline and after 12-week intervention. Objective physical measurements were performed by trained and blinded assessors unaware of the assignment information.

At the baseline and post training period were performed following assessments:

* anthropometrics using digital stadiometer
* body composition tested by the dual X-ray absorptiometry method
* bone mineral density tested by the dual X-ray absorptiometry method
* questionnaire assessment of: (i) quality of life using EORTC QLQ-C30 Questionnaire version 3.0, EORTC QLQ-BR23 Questionnaire Breast cancer module), (ii) pain using Brief Pain Inventory Short Form Questionnaire), (iii) level of physical activity using IPAQ Questionnaire
* myofascial stiffness using myotonometr and a non-invasive shear-wave elastography examination
* respiratory function measured with spirometric tests
* cardiorespiratory fitness measured with: (i) cardiopulmonary exercise test CPET on the treadmil, (ii) metabolic response assessment with blood lactic acid concentration, (iii) subjective rating of perceived exertion with the Borg 6-20 scale
* vascular circulation indicators measured with the use of the Flow Mediated Skin Fluorescence
* inflammatory hematological ratios were calculated based on hematological medical patients indicators.

Patients characteristics has been completed by medical records and socio-demographic questionnaires.

The supervised physical activity intervention using the Pilates Method (60min each session, 2 sessions each week over 12 weeks) was used in this study.

In the study took part two groups - Exercise Group (experimental group performing PM intervention) and Usual-Care Group (control group).

The training program involved exercise performed on mats. The subjects took part in a model training session, during which all exercises were explained, performance was discussed, common mistakes were pointed out, and efforts were made to maintain proper exercise intensity and muscle activation and relaxation.The model PM training sessions was consisted of:

1. warm-up and respiratory exercises (5-10 min);
2. mat Pilates exercises with the traditional Pilates repertoire (basic, beginner) adapted for breast cancer patients needs and restrictions (40 min);
3. cool down and endings exercises (5 min);
4. session summary (2-3min). The training program was supervised by the same specialist of PM.

Eligibility Criteria:
Inclusion Criteria:

1. women with invasive breast cancer
2. stage of disease according to TNM classification I-III
3. cancer with estrogen receptor expression in at least 10% of cell nuclei
4. supplemental hormone therapy with an aromatase inhibitor used for at least 6 months
5. performance status according to ECOG classification 0-1
6. BMI of 18.5-30
7. without chronic diseases affecting the limitation of the use of oncological treatment
8. without contraindications to participation in group supervised Pilates classes
9. participation in at least 17 of 24 classes according to the proposed schedule

Exclusion Criteria:

1. invasive breast cancer stage IV according to TNM classification
2. performance status according to ECOG classification 2-4
3. unregulated hypertension
4. unstable ischemic heart disease
5. arrhythmia
6. rheumatic diseases
7. osteoporosis
8. advanced osteoarthritis
9. disease of rheumatic origin (AS, RA, fibromyalgia)
10. pregnancy
11. BMI \< 18.5 or above 30
12. unregulated hypothyroidism/hyperthyroidism

Criteria for drop out The criteria for discontinuing allocated interventions are as follows: 1) participant's voluntary withdrawal from the study; 2) worsening of oncological prognosis that prevents the continuation; 3) absence of training sessions due to unjustified reasons in the case of the PG (compliance below 70%).