Eye-Hand Cross-Dominance and Upper Extremity Performance in Volleyball Players

Comparison of Upper Extremity Muscle Strength and Motor Performance Between Volleyball Players With and Without Crossed Eye-Hand Dominance

Eye and hand dominance may influence visuomotor coordination, motor control, and upper extremity performance in athletes. Crossed eye-hand dominance occurs when the dominant eye and dominant hand are located on opposite sides of the body. However, evidence regarding the relationship between crossed eye-hand dominance and upper extremity performance in volleyball players remains limited.

This observational cross-sectional study aims to compare upper extremity muscle strength and motor performance between volleyball players with and without crossed eye-hand dominance. Participants' eye and hand dominance will be determined using standardized assessments. Upper extremity muscle strength and motor performance outcomes will then be measured and compared between the two groups.

Inclusion Criteria:

• Aged between 18 and 30 years.
• Male or female volleyball player.
• At least three years of active volleyball participation.
• Currently training at least three days per week.
• No upper extremity injury within the previous six months.
• Normal or corrected-to-normal visual acuity with eyeglasses or contact lenses.
• Willing to participate and able to provide written informed consent.

Exclusion Criteria:

• History or presence of an acute or chronic musculoskeletal disorder that may affect study assessments.
• Presence of a neurological or vestibular system disorder.
• Presence of visual field loss, strabismus, or a severe refractive error that cannot be adequately corrected.
• History of shoulder, elbow, or hand surgery within the previous six months.
• Not currently participating regularly in volleyball or structured exercise.