## 1 Introduction  
A comprehensive analysis of postural abnormality is necessary, since many healthcare practitioners often deal with lower-extremity musculoskeletal disorders (MSD) that could potentially influence people's quality of life [1]. Among all diseases in Saudi Arabia, MSD was seventh in prevalence with an age-standardized prevalence of 19.05% in 2019. Additionally, MSD were the second-highest cause of disability between 1990 and 2019, affecting more women than men [2]. Typically, young females with MSD experience balance abnormality which mostly affects their dynamic balance [3, 4]. Proper dynamic balance is necessary for implementing a number of daily functional tasks, such as walking, stair negotiation, as well as for occupational tasks and leisure [5]. Clinically, Star Excursion Balance Test (SEBT) is a widely used assessment tool that is commonly conducted to evaluate dynamic balance irregularities. The SEBT has been simplified into three main directions: the anterior (ANT), posteromedial (PM), and posterolateral (PL) directions, and termed as modified star excursion balancing test (mSEBT).  
Similar to SEBT, healthcare providers commonly use mSEBT to assess dynamic balance [6] as it considered reliable and valid method when used with both healthy and injured individuals [7, 8]. Moreover, the mSEBT test offers a practical alternative to less comprehensive assessments such as measurements of range of motion [6]. The test scores have also been related to lower extremity deficits in patients with lower extremity MSD and have been shown to be injury predictors in athletes [9; 10]. Although understanding the association between postural stability and the strength of lower extremity muscles may be crucial to recognize individuals who are more susceptible to injury [11], previous studies were limited to assess the association between the reached distance values and lower extremity strength in old age or sports injuries individuals [12; 13; 14]. No studies to date have examined the association between mSEBT and the strength of lower extremity muscles in young healthy females.  
The balance test requires strength, as well as flexibility, however, the mSEBT is merely a test and does not assess the etiology of the disorder [15]. Therefore, the mSEBT may be useful in exploring flexibility asymmetries and flexibility deficiencies in the lower extremity in healthy adults, but other tests may also be integrated in order to provide a more comprehensive view of functional mobility and injury risk [16]. Recently, [PERSON] and [PERSON] hypothesized that improvements in hip muscle flexibility could improve balancing capacity through changing hip joint strategies [17].  
Understanding these relationships is crucial not only for expanding our knowledge of dynamic balance in this population, but also for identifying individuals who may be more susceptible to injury. The insights from this study may have implications for the development of targeted interventions to enhance balance, particularly in anterior and posteromedial reach movements. Such interventions could benefit a range of individuals, from athletes to those undergoing physical therapy, by optimizing both flexibility and strength for specific reach movements. As a result, investigating the correlation between mSEBT and lower limb muscular flexibility and strength is of clinical importance. A societal investigation is still needed to assess balance and lower limb muscular strength and flexibility. To the best of our knowledge, convincing data on female Saudi populations are not yet available. Hence, the main objective of this study was to establish the association between the mSEBT score and the strength and flexibility of lower extremity muscles in young healthy Saudi females.