The purpose of this randomized controlled study is to investigate the immediate effects of ankle joint mobilization on countermovement jump performance and ankle dorsiflexion range of motion in healthy university students. Participants will be randomly assigned to either an ankle joint mobilization group or a sham mobilization group. Countermovement jump performance will be assessed using the My Jump Lab mobile application, and ankle dorsiflexion range of motion will be measured using the weight-bearing lunge test with a digital inclinometer before and immediately after the intervention. The findings of this study are expected to improve the understanding of the acute effects of ankle joint mobilization on functional performance and ankle mobility.

Vertical jump performance is an important indicator of lower-extremity explosive power and neuromuscular function. Adequate ankle dorsiflexion range of motion plays a critical role in force production, movement efficiency, and landing mechanics during jumping tasks. Previous studies have demonstrated that ankle joint mobilization can improve dorsiflexion range of motion through mechanical and neurophysiological mechanisms. However, limited evidence exists regarding whether these immediate improvements in ankle mobility translate into enhanced jump performance in healthy individuals.

This randomized controlled study aims to evaluate the immediate effects of ankle joint mobilization on countermovement jump performance and ankle dorsiflexion range of motion in healthy university students.

Approximately 50 healthy university students will be recruited and randomly allocated to either an ankle joint mobilization group or a sham mobilization group (25 participants per group). Before the intervention, all participants will undergo assessments of countermovement jump performance using the My Jump Lab mobile application and ankle dorsiflexion range of motion using the weight-bearing lunge test with a digital inclinometer.

Participants in the intervention group will receive ankle joint mobilization using the Mobilization with Movement (MWM) technique. Participants in the sham group will be positioned similarly and perform the same movement without the application of therapeutic posterior talar glide. Immediately after the intervention, all outcome measures will be repeated using the same standardized procedures.

The primary outcome will be countermovement jump performance, while the secondary outcome will be ankle dorsiflexion range of motion. The results of this study may provide evidence regarding the immediate effects of ankle joint mobilization on functional performance and may contribute to the development of evidence-based manual therapy interventions for improving lower-extremity performance

Inclusion Criteria:

• Healthy university students aged 18-30 years.
• Willing to participate and provide written informed consent.
• No history of lower extremity musculoskeletal injury or surgery within the -previous 6 months.
• No neurological or vestibular disorders affecting balance or movement.
• No contraindications to manual therapy.

Exclusion Criteria:

• Current pain in the lower extremity or spine.
• History of ankle fracture or surgery.
• Acute lower extremity injury within the previous 6 months.
• Any systemic, neurological, or rheumatological disease affecting movement.
• Participation in another intervention study during the study period.
• Inability to complete the assessment procedures.

Individual participant data will not be shared because the study involves a limited number of participants and no consent for public sharing of anonymized individual-level data was obtained. Aggregate study results will be reported in scientific publications.

Participants and outcome assessors will be blinded to group allocation. Both groups will undergo procedures in similar positions and will receive identical movement instructions. The intervention group will receive a therapeutic posterior talar glide during the mobilization procedure, whereas the sham group will perform the same movement without the application of mobilization force. The researcher administering the intervention will not be blinded. Outcome assessments will be performed by a separate researcher who is unaware of group allocation.