Myofascial System and Physical Exercise: A Narrative Review on Stretching (Part I).

Over the past 20-30 years, numerous studies have expanded our understanding of the connective components within the human musculoskeletal system. The term "fascia" and, more specifically, the "fascial system" encompass a variety of connective tissues that perform multiple functions. Given the extensive scope of the topic of fascia and the fascial system, which cannot be fully addressed in a single article, this work will focus specifically on the role of fascia in tension transmission (mechanotransduction). This includes both the tensions generated by the contractile muscular component and the elastic recoil, which contribute to movement and posture in the human body. A functional alteration of the fascia, due to the high density of receptors within it, can trigger pain symptoms identified as myofascial pain; this typically manifests at so-called myofascial trigger points (MTrPs). This article presents a new hypothesis on how MTrPs may develop as a result of imbalanced tension loading on the fascial components arranged in series and parallel to the contractile muscular component. While the literature contains several studies on the manual manipulation of fascia, limited evidence is available regarding the treatment of fascial dysfunctions through alternative modalities, such as therapeutic exercises aimed at lengthening or shortening these structures. This work is divided into two parts: the first section provides an overview of the composition of fascia used for the transmission of tension forces and introduces the basis of the approach, using stretching techniques, to address dysfunctions related to excessive rigidity in the myofascial system. Additionally, a mechanical physiological basis is proposed for the various stretching methods described in the literature. The second part addresses the treatment of dysfunctions related to reduced rigidity in the fascial system through therapeutic exercise. The fascial training recommendations provided in this article are aimed at preventing and treating musculoskeletal disorders. They should be integrated with muscle-strengthening work, cardiovascular training, and coordination exercises. Developing a fascial network in the body that is both flexible and resistant to injury involves applying recent discoveries from the rapidly advancing field of fascia research into effective training programs. This paper aims to motivate physiotherapists, osteopaths, sports trainers, and other movement instructors to integrate these principles and adapt them within their professional practices.