Inclusion criteria:
Completing the voluntary company consent form
10 to 13-year-old elementary school girl students
Having smooth, flexible soles in both feet (grade two flat soles and navicular drop more than 10 mm)
Having crossed knee deformity (second degree)
Normal body mass index is between 18.5 and 24.9
Not participating in any other experimental or treatment program during the trial
Absence of cardiovascular diseases, diabetes, asthma
Absence of knee brace and backward knee abnormalities
Absence of pain, physical disability, orthopedic problem
Absence of abnormal range of motion of lower limb joints
No history of previous injuries and muscle disorders in the lower limbs
Exclusion criteria:
People with cardiovascular diseases, diabetes, asthma, deformities of bow-legs and Genu recurvatum knee
Presence of pain, physical disability, medical prohibition or orthopedic problem
Abnormal range of motion of lower limb joints
Having a history of previous injuries and muscle disorders in the lower limbs
Absence of more than 2 sessions in practice sessions
Dissatisfaction, withdrawal or non-cooperation