The aim of this study is to examine, using a comparative and experimental approach, the effects of nomophobia (fear of being without a smartphone) levels on acute neuromuscular and cognitive fatigue susceptibility induced by a standard physical exertion in young adults.

This project aims to fill a significant gap in the literature by examining the effects of Nomophobia (No Mobile Phone Phobia), one of the rapidly increasing behavioral problems of the digital age, on cognitive performance and the neuromuscular system through objective physiological measurements.

Nomophobia is increasing, especially among young adults, with the widespread use of smartphones; it is closely associated with high anxiety, distractibility, and stress levels . Studies in the literature have reported significant correlations (r ≈ 0.45) between Nomophobia and stress. However, the vast majority of these studies are based on subjective scales and do not provide objective data that directly examine neuromuscular and physiological effects. Therefore, the somatic reflections of psychological stress related to Nomophobia on muscle mechanics and cognitive resilience have not been sufficiently explained.

Smartphone users, particularly those in their adolescence and twenties, are at higher risk for musculoskeletal disorders due to prolonged and repetitive static positions. This leads to fatigue and pain in the neck (Sternocleidomastoid - SCM, Upper Trapezius), upper extremity (Flexor Carpi Radialis - FCR), and trunk (Lumbar Erector Spinae - LES, Rectus Abdominis) muscles

This project will objectively evaluate the effects of nomophobia-induced psychological stress on two key physiological domains to demonstrate its amplifying effect on this pre-existing physiological sensitivity:

Cognitive Performance: Examining the prolongation of Reaction Time (RT) in attention-demanding tasks after acute physical exertion in individuals with high levels of nomophobia. Cognitive performance will be assessed using the Nelson Hand Reaction Time Test (Simple Reaction Time - SRT), which measures the speed of a participant's hand motor response to a visual stimulus in milliseconds (ms).

Neuromuscular Response: Assessment of stiffness (ΔStiffness) and mechanical recovery rate (ΔDecrement) in postural (SCM, Upper Trapezius, LES) and functional (FCR, Rectus Abdominis) muscles as measured by MyotonPRO.

Physiological Cost: Determination of resistance sensitivity to fatigue through comparison of Core Endurance Time (seconds) achieved in maximal plank exercise .

In this respect, the project aims to demonstrate with scientific evidence that Nomophobia is not only a psychological condition but also a systemic stress factor that increases cognitive and neuromuscular sensitivity, by integrating the disciplines of behavioral psychology, physiology, and biomechanics. Research Question: Are young adults with high levels of Nomophobia more susceptible to cognitive and neuromuscular fatigue after acute physical exertion compared to those with low levels?

Key Hypotheses:

Individuals with high levels of Nomophobia will have a significantly higher percentage increase in Reaction Time (RT) after acute exertion.

Increased stiffness (ΔStiffness) and loss of elasticity (ΔDecrement) in postural and functional muscles will be more pronounced after the maximal plank test.

Individuals with high levels of Nomophobia will have a significantly shorter endurance time (seconds) in the Maximal Plank Position Endurance Test.

Expected Outcome: These findings will provide unique and objective evidence regarding the effects of technological addiction on neuromuscular health, demonstrating that individuals with high levels of nomophobia are more susceptible to both cognitive and physiological burnout.

Inclusion Criteria:

• Being between 18-25 years of age.
• Agreeing to participate in the study voluntarily and signing the Informed Consent Form.
• Being literate in Turkish.
• Being able to complete the Nomophobia and PAS scales.

Exclusion Criteria:

• Having undergone musculoskeletal surgery within the last 6 months.
• Having any chronic neurological or orthopedic condition that would prevent participation in the experimental protocol (e.g., herniated disc, fibromyalgia, cervical disc herniation, etc.).
• Taking medications that may affect muscle tone or pain perception continuously (e.g., antidepressants, antispasmodics, muscle relaxants).
• Having a diagnosed serious psychiatric disorder (clinical depression, bipolar disorder, etc.).
• Having a cardiovascular or respiratory disease that would prevent maximum physical exertion during the protocol.

SEDENTARY HEALTHY YOUNG ADULTS