This study will evaluate whether the short-term use of activity tracking devices improves short-term weight loss in adolescents. The investigators will evaluate whether weight loss translates into a change in obesity-related biomarkers associated with adolescent obesity. In addition, the investigators will report outcomes after the implementation of activity tracking devices in conjunction with an intense adolescent weight loss program.

This study will evaluate the short-term use of activity tracking devices and their effects on short- and long-term weight loss in adolescents. The investigators plan to establish whether weight loss translates into a change in obesity-related biomarkers associated with adolescent obesity. Each participant with an activity tracking device will have the goal of reaching 10,000 steps per day, in addition to their individual fitness plan.

Inclusion Criteria:

Ages 12-18 years BMI ≥ 95th percentile for age and sex group Participant able to read and understand English Willingness to be randomized to any condition

Exclusion Criteria:

Inability to obtain informed parental consent and/or child assent Inability to participate in the program due to pre-existing conditions (e.g., paralysis, heart failure, severe autism or mental retardation, psychosis) Pregnancy Clinical judgment concerning safety Inability of the participant to speak English

The investigators will provide all data, regardless of publication, collected as part of this project. All external investigators must submit a written request identifying their research question(s) and specifying the data they are requesting. The request must include a data security plan and explanation of how the data will be stored and who will have access.

Data will only be available upon request

The request must include a data security plan and explanation of how the data will be stored and who will have access.