Adapted Physical Activity as Complementary Treatment to Alleviate the Symptoms of Endometriosis? The CRESCENDO Program (inCRease Physical Exercise and Sport to Combat ENDOmetriosis)

a. Objectives and research hypothesis

1. Endometriosis and its consequences Endometriosis is a chronic disease characterized by growth of endometrial tissue outside the uterine cavity which affects 200 million women (The investigators use the word "women" generically. However, this study takes into account gender identity. In other words, a person with endometriosis may identify as a man, as woman or no/other gender.) worldwide. In addition to infertility, one of the most common symptoms of endometriosis is pelvic chronic pain. Evidence has suggested that these symptoms result from a local inflammatory peritoneal reaction caused by ectopic endometrial implants that undergo cyclic bleeding. This disease generates significant health care costs (e.g., 9,5 billion in France) because there is no definite cure for it and its management involves pain related treatment and/or surgery. Research showed that these treatments are only relatively effective in reducing pain.

This pain can cause psychological distress and interpersonal difficulties that are as difficult to live with as the pain itself. Compared to women who do not suffer from endometriosis, women with this disease develop a lower sense of femininity, altered body image, higher levels of stress, depression and anxiety. These factors affect their quality of life (QoL) and can have deleterious effects on the response to treatment. Interpersonal relationships are also impacted such as romantic, professional and social relationships, because the symptoms make it difficult to move and carry out daily activities. However, studies on the psychological and social consequences of endometriosis are scarce, few have investigated life-partners' view of the disease and its consequences, and all adopt cross-sectional designs. 2. The effects of physical activity on endometriosis: a question for further investigation In their recent publication, INSERM (L'Institut national de la santé et de la recherche médicale) highlights the beneficial effects of regular physical activity (PA) and adapted physical activity (APA) on chronic diseases. Research suggested that (A)PA may have a beneficial effect on the physical symptoms and the psychological and social consequences of these diseases, thus may be also in endometriosis context. However, studies questioning the link between PA and endometriosis (and its symptoms) are rare, cross-sectional, and their results are inconsistent. The scarcity of studies can be explained by the fact that due to the painful symptoms caused by the disease; women do not practice much PA spontaneously and autonomously or even avoid practicing. In addition to this difficulty, widely recognized barriers to PA (i.e., lack of time, lack of adequate and nearby infrastructure, and low self-confidence and motivation for PA) can also contribute to the low level of PA. It is worth noticing that, in the specific context of endometriosis, the barriers and facilitators to the practice of PA are not clearly identified. Otherwise, due to their cross-sectional design, it was not possible for these studies to establish a causal link between PA and endometriosis. A randomized controlled trial (RCT) is needed to test the effects of (A)PA on the symptoms of endometriosis and its consequences. 3. Summary of scientific barriers to be lifted

Based on previous research and their limits, there are three major scientific barriers to be lifted regarding the investigation of the link between (A)PA and endometriosis:

1. There is a need to better understand the psychological and social factors associated to endometriosis. For instance, consequences of endometriosis on these factors and the impact of the disease in romantic relationships (i.e., on the patient and on her life partner2) need to be more documented. Some of these factors could be related to patient PA or could mediate or moderate the relation between endometriosis (and its symptoms) and PA.
2. Although barriers of PA are well known, in the context of endometriosis the barriers and facilitators to the practice of PA are not clearly identified. Given the specificity of this disease which only affect women and its impact on body functioning and body perception, this topic deserves to be investigated.
3. Otherwise, due to their scarcity and their cross-sectional design, it was not possible for previous studies to strongly establish a causal link between PA and, endometriosis and its symptoms. Conducting a RCT may help to overcome this limitation.