This pilot randomized controlled trial will investigate the effects of a 7-week core stabilization program performed on stable versus unstable surfaces in young competitive rhythmic gymnasts. Sixteen athletes will be randomized into two groups and will be assessed for changes in static balance and pivot performance.

Rhythmic gymnastics requires high-level neuromuscular control, especially for skills involving balance and rotation. Core stabilization exercises are commonly included in training, but limited evidence exists regarding the impact of surface type on training effectiveness. This pilot study will compare the effects of a 7-week core stabilization program conducted on stable versus unstable surfaces on balance and pivot execution in rhythmic gymnasts aged 7-12. Participants will be randomly allocated into two equal groups and will be assessed pre- and post-intervention on selected balance and pivot tasks in accordance with Fédération Internationale de Gymnastique (FIG) standards. The study aims to inform future trials by estimating effect sizes and assessing the feasibility of the protocol.

Inclusion Criteria:

• Female rhythmic gymnasts aged 7 to 12 years
• Minimum of 1 year of experience in rhythmic gymnastics
• Active participation in organized training at least 3 times per week
• No current musculoskeletal pain or injury
• Ability to perform all training and assessment tasks safely
• Written informed consent provided by a parent or legal guardian

Exclusion Criteria:

• History of acute lower limb or spinal injury within the past 6 months
• Presence of neurological, orthopedic, or vestibular disorders affecting balance
• Concurrent participation in other structured physical training programs outside rhythmic gymnastics
• Any medical condition that would contraindicate participation in physical exercise