This study aims to identify injury risk factors using a clinical/functional test battery in university basketball and volleyball athletes, to develop individualized exercise prescriptions for athletes scoring below established cut-off values on each test, and to evaluate the effects of an 8-week intervention program on test parameters.

As a secondary aim, all participants will be monitored prospectively over a 6-month season to assess the incidence of injuries and health problems, and to evaluate the contribution of the individualized program to injury-related health outcomes.

The study consists of four phases: (1) baseline cross-sectional assessment (T0), (2) 8-week individualized exercise intervention for athletes below cut-off thresholds, (3) post-intervention reassessment (T1), and (4) 6-month prospective injury surveillance (T2).

BACKGROUND:

Musculoskeletal injuries in athletes represent a significant sports medicine and public health problem due to restricted training/competition participation, prolonged rehabilitation, and increased re-injury risk. Epidemiological data indicate that basketball and volleyball athletes carry elevated risk for lower extremity sprains/strains, knee ligament injuries, and overhead-related shoulder pathologies. University athletes are particularly vulnerable given the concurrent demands of intense academic schedules and high training loads.

Clinical/functional tests can systematically identify modifiable risk factors including neuromuscular control, balance, flexibility, and functional strength. The Y-Balance Test (YBT-LQ), Hop-for-Distance Test (Limb Symmetry Index), Active Straight Leg Raise (ASLR), Closed Kinetic Chain Upper Extremity Stability Test (CKCUEST), and Glenohumeral Internal Rotation Deficit (GIRD) assessment are employed in this study, each with established reliability and predictive validity.

STUDY DESIGN:

This is a non-randomized, parallel-group interventional study. Athletes scoring below literature-defined cut-off values on any test receive test-specific individualized exercise prescriptions (Intervention Group), while athletes meeting all cut-off thresholds receive no intervention and serve as the observation group. Both groups undergo identical assessment at T0 and T1, and are monitored for injuries through T2.

INTERVENTION:

The 8-week individualized exercise program is prescribed based on each athlete's specific deficits:

• YBT-LQ below cut-off (composite score less than 94% or asymmetry greater than 4 cm): Dynamic balance and proprioception exercises
• Hop Test LSI below 90%: Plyometric control and symmetry exercises
• ASLR below 70 degrees: Hamstring/posterior chain flexibility exercises
• CKCUEST below cut-off (males less than 21, females less than 23 touches): Scapular stability and upper extremity endurance exercises
• GIRD above cut-off (internal rotation deficit greater than 20 degrees or total rotation difference greater than 5 degrees): Posterior shoulder capsule and rotator cuff exercises

Frequency: 3 days/week, 20-30 minutes per session. First 2 weeks supervised, subsequent weeks partially independent. Weekly compliance logged.

INJURY SURVEILLANCE (T2):

All participants are monitored for 6 months using IOC 2020 Consensus Statement methodology. Events are classified by type (injury/illness), onset (acute/overuse), anatomical region, severity (time-loss days), and recurrence status. Participant reports are cross-checked with team staff records where available.

STATISTICAL ANALYSIS:

Descriptive statistics (mean +/- SD, median, frequencies). T0-T1 comparisons: paired t-test or Wilcoxon signed-rank test (only athletes below cut-off for each respective test). Between-branch comparisons: independent t-test / Mann-Whitney U, chi-square / Fisher exact test. Effect sizes (Cohen's d). Injury incidence comparison between intervention and observation groups at T2. Significance level: p less than 0.05.

Inclusion Criteria:

• Active member of Acibadem University basketball or volleyball team
• Regular training within the past 6 months
• Age 18 years or older
• Willing to participate and provide written informed consent
• Physical and cognitive capacity to complete test protocols

Exclusion Criteria:

• Surgical intervention within the past 6 months
• Acute musculoskeletal injury within the past 2 weeks (acute sprain/strain/contusion etc.) that would preclude testing
• History of vestibular disorder, neurological disease, or systemic condition that may affect balance testing
• Uncontrolled cardiovascular disease/hypertension or other medical condition contraindicating exercise
• Pregnancy or within the first 6 months postpartum (female athletes)
• Refusal to provide informed consent

Open label. No masking is employed. Group allocation is based on objective test results against pre-defined cut-off values, making blinding not feasible.