Acute lymphoblastic leukemia (ALL) is the most common cancer in children and, along with lymphoblastic lymphoma, represents the most common group of childhood lymphoid malignancies. Survival rates have improved over the years, but many children still experience long-term side effects from treatment. These can include tiredness, weak muscles, pain, nerve problems, difficulty moving, and other physical challenges. Many children with ALL are also overweight at diagnosis, and weight gain often continues during treatment. As a result, about half of childhood leukemia survivors have a BMI at or above the 85th percentile.

Treatment decisions are usually based on a child's symptoms and genetic risk factors. However, some risk factors such as physical activity can be modified. Exercise during treatment may help children feel better and may even improve survival. However, research on early symptom tracking and structured exercise during the first phase of chemotherapy is limited, uses different methods, and often does not include reliable patient-reported symptoms.

Effective exercise programs for children with ALL and lymphoblastic lymphoma need to consider the child's age, treatment side effects, motivation, family support, and ways to encourage long-term behavior change. Because children spend little time in the hospital during the induction phase, a mix of in-person and virtual sessions supported by real-time Zoom instruction can make it possible to offer safe and supervised exercise at home.

This study will use a guided exercise plan that includes tools to track sets, repetitions, intensity, warm-up time, and perceived exertion. These tools help with consistent monitoring and support both patients and caregivers throughout the program. Twenty children newly diagnosed with ALL or lymphoblastic lymphoma who receive standard 3-4 drug induction chemotherapy will be invited to participate. Our goal is to determine whether a 9-week hybrid exercise program, combined with weekly symptom check-ins, is practical and achievable in both hospital and home settings.

Inclusion Criteria for children:

All subjects must meet the following criteria:

• Written informed consent obtained to participate in the study and HIPAA authorization for release of personal health information. OR Written assent and parental/legal guardian consent.
• Age >= 6 and < =21 years at the time of diagnosis.
• Newly- diagnosed with one of the following diseases: B-cell or T-cell Acute Lymphoblastic Leukemia or Lymphoblastic Lymphoma

Exclusion Criteria for children:

• Subjects must not be receiving any investigational or additional anti-cancer medicines during induction.
• Significant concurrent disease, illness, or psychiatric disorder or social issue that would compromise subject safety or adherence to the protocol treatment or procedures, interfere with consent, study participation, follow-up, or interpretation of the study results.

Optional caregiver participation:

Inclusion Criteria :All caregivers must meet the following criteria

• Written informed consent to participate in the caregiver interviews.
• The caregiver must be a parent or legal guardian ≥ 18 years old, and their child must be <18 years