# Stretching and Eccentric Exercises Normalize Gait Parameters in Gastrocnemius Tightness Subjects
## 1 Introduction  
Isolated gastrocnemius tightness (IGT) is a widely encountered condition associated with various foot pathologies, including metataralsalgia and hallux valgus [1, 2, 3]. The prevalence of IGT is challenging to determine accurately due to the lack of a consensus definition and validated measuring device [4]. However, IGT is believed to be a commoncondition [4], with some studies reporting a prevalence of up to 50% in the general population [5]. Furthermore, in cases involving foot pathology, the prevalence of IGT can reach as high as 96.5% [6]. In the surgical community, it is generally assumed that IGT induces ankle dorsiflexion restriction during the midstance phase of the gait, which would induce an increase in forefoot plantar pressure [7]. This hypothesis is supported by studies involving 3D models or cadaveric specimens [8; 9]. However, it is important to note that these studies were not conducted on living subjects and remain speculative. Laboratory gait analyses conducted on living subjects have yielded inconsistent results regarding the restriction of ankle dorsiflexion in individuals with IGT. Contrary to the hypothesis, studies have not consistently found evidence supporting restricted ankle dorsiflexion during the midstance phase except in specific populations with neuropathic involvement [10; 11; 12]. Moreover, gait analysis studies have reported increased knee flexion during the gait without restricted ankle dorsiflexion [13; 14]. However, these studies focused on unilateral IGT patients with associated forefoot pathologies and utilized force plates, which do not provide detailed information on localized forefoot pressure [13; 14]. In an attempt to address these limitations, we conducted a study comparing asymptomatic bilateral IGT subjects and controls, using quantitative gait analysis and dynamic baropodometry [15]. Similarly, our findings contradicted our initial hypothesis, as we did not observe restricted ankle dorsiflexion or increased forefoot pressure during the midstance phase in the individuals with bilateral IGT. Instead, we observed knee flexion during this phase, as was previously reported [13; 14]. The discrepancy between the clinical and laboratory results can be attributed to compensatory mechanisms such as increased knee flexion, which allows gastrocnemius relaxation, thus releasing the ankle dorsiflexion restriction [15]. However, the exact pathophysiological link between IGT and foot pathologies remains unexplained, highlighting the incomplete understanding of gastrocnemius tightness and the potential for management errors such as inappropriate lengthening procedures [16]. Knowing the gait pattern of IGT subjects is still valuable, and we can assume that correcting gait disorders in these subjects could treat or prevent IGT-related pathologies. Assuming that knee flexion is a compensatory mechanism in IGT subjects to allow ankle dorsiflexion during the midstance phase, we can hypothesize that IGT treatment could result in the disappearance of this gait compensation. Although stretching and eccentric exercises are commonly used for IGT management, their impact on gait parameters remains poorly understood. Isolated gastrocnemius tightness can be treated in a variety of ways, from simple stretching to surgical lengthening [16; 17; 18; 19]. There is currently no consensus on the type of stretching or physical therapy to use to treat IGT. However, the Stanish protocol, although originally described for Achilles trantionopathy, includes calf stretching and eccentric exercises, both of which are recognized as effective for IGT [17; 20; 21; 22]. In our center, this is the protocol we routinely use, as it is well known and easy to implement, whether with a physiotherapist or as self-rehabilitation. From a research point of view, the use of this predefined, well-known protocol will contribute to improved external consistency and clinical applicability of study outcomes.