Analysing The Impact of Foot Arch Height on Leg Muscle Tone and Balance in Young Adults.

Foot posture abnormalities due to high or low arches, such as pes planus (flatfoot) and pes cavus (high-arched foot), significantly impact daily activities, particularly among young adults engaged in prolonged standing, walking, or physical activities. Pes planus is commonly associated with ligamentous laxity, muscle weakness, or genetic predisposition, leading to diminished medial, lateral, and transverse arches, resulting in excessive pronation, instability, and compromised shock absorption. This has been linked to knee pain and altered lower extremity alignment, and individuals with pes planus often experience foot pain, fatigue, and reduced physical performance.

Conversely, pes cavus is characterized by an exaggerated medial and lateral arch and diminished transverse arch, often linked to neuromuscular disorders, tight plantar fascia, or congenital factors. This condition leads to reduced shock absorption and uneven weight distribution, increasing the risk of recurrent ankle sprains, calluses, and metatarsalgia. Individuals with pes cavus frequently encounter discomfort during weight-bearing tasks and difficulties maintaining balance, which can hinder participation in physical and social activities.

Pes planus is linked to excessive pronation, while pes cavus is associated with excessive supination and rigidity, limiting adaptive responses to uneven surfaces. Both conditions have been associated with deficits in static and dynamic balance due to altered foot and lower limb alignment, leading to postural instability and increased sway during quiet standing and movement tasks. These balance deficits highlight the need for comprehensive assessments to identify individuals at greater risk of mobility impairments.

Lower extremity muscle tone plays a critical role in postural stability and overall functional movement, contributing to joint stabilization, shock absorption, and postural control during both static and dynamic activities. Individuals with lower muscle tone and stiffness have been shown to exhibit greater postural sway, indicating reduced postural control. Myotonometry provides reliable, repeatable, and non-invasive measurement of muscle tone, stiffness, and elasticity. Muscle strength and power also play a crucial role in foot function, balance, and postural stability by providing the necessary force for efficient movement and weight-bearing. Deficiencies in muscle power can lead to compensatory movement patterns that increase the risk of falls and injuries, particularly in individuals with foot posture abnormalities.

Prior research has examined dynamic balance, static balance, and muscle tone across different foot arch types separately, but no study has integrated foot posture, static and dynamic balance, muscle tone, and muscle strength within a single framework. This study addresses that gap by evaluating these factors together to provide a more comprehensive understanding of how foot posture abnormalities influence postural stability across genders.

Aim of Study

This study aims to examine how different foot arch types (pes planus, pes cavus, and normal arch) affect lower extremity muscle tone, muscle strength, and static and dynamic balance, in order to better understand their impact on postural stability and movement efficiency. The primary goals are to examine the relationship between foot posture abnormalities and muscle tone, balance performance, and strength in young adults; to identify differences in these factors based on gender; and to determine the functional impact of foot posture on stability, movement efficiency, and injury risk.

Hypotheses

The null hypothesis states that foot posture (pes planus, pes cavus, and normal arch) has no significant effect on static and dynamic balance performance, lower limb muscle tone, or muscle strength. The alternative hypothesis states that foot posture significantly affects static and dynamic balance performance, lower limb muscle tone, and muscle strength, with variations in arch structure influencing postural stability and muscle function, and that this effect differs between male and female participants.

Overview of Procedures

Participants will be classified into one of three foot arch groups using the Arch Height Index and confirmed with the Foot Posture Index-6. Each participant will complete a sociodemographic questionnaire and anthropometric measurements, followed by static balance assessment (Single Leg Stance), dynamic balance assessment (Star Excursion Balance Test and Single-Leg Hop for Distance), muscle tone assessment using a myometer, and muscle strength assessment using a handheld dynamometer. Assessments will be conducted in a standardized order for all participants to minimize order-related bias. Detailed eligibility thresholds and outcome measure definitions are provided in the corresponding registration modules.

Inclusion criteria

• Aged 18-25 years old-
• Not diagnosed with other medical conditions, fractures, or deformities
• No prior foot or lower limb surgeries affecting musculoskeletal health
• Wears sport shoes majority of the time

Exclusion criteria

• Neurological Disorders: Conditions affecting balance or muscle tone
• Balance Disorders like vestibular or inner ear conditions
• Women that wears high heels majority of the time
• Men that wear stiff and hard material shoes majority of the time