• To compare between modified strength training program and aerobic exercises on quality of life on children with Acute Lymphoblastic Leukemia.
• To compare between modified strength training program and aerobic exercises on functional capacity on children with Acute Lymphoblastic Leukemia.

This study will be done to determine any exercise from aerobic exercises or modified strength training program will be more effective on quality of life and functional capacity on children with Acute Lymphoblastic Leukemia .Acute Lymphoblastic Leukemia is wide spread in the world and the children with this disease are fragile so must know the most program effect.

Inclusion Criteria:

• Age range from8-12years.
• Children during 3rd phase( maintenance phase of the treatment). According San et al(2007) who found children with Acute Lymphoblastic Leukemia in maintenance phase of treatment can safely perform both aerobic and resistance training .
• Time elapsed since the start of the maintenance phase >20weeks.
• Children with muscle weakness due to chemotherapy.
• The height , weight and body mass index of the child will take on standard scale.
• preserved cardiac structure and function as assisted by echo-cardiogram.
• The children have ability to walk.

Exclusion Criteria:

Children who have one or more of the following criteria will be excluded from the study:

• Receiving more intensive chemotherapy.
• Mental disabled.
• Sever cardiomyopathy (ejection fraction <40%, ECG will be used as a pretest as it might be a more sensitive tool to exclude angina pectoris).
• Low blood platelet levels (< 50.000 per µl).
• Marked anemia (hemoglobin < 8 g/dl).
• Severe cachexia (i.e., weight mass loss > 35%).
• Pain in bone.
• Inability to walk.
• Sensory disturbance.
• Peripheral neuropathy.