The study will run from August 2008 to May 2009. Recruitment and screening of participants will occur from August to December 2008 for inclusion into the clinical trial. Prior to the clinical trial participants will have a one hour informational session to clearly present the study, obtain signed informed consent and set up fitness/blood appointments for data collection. Data collection will begin the first week of school in January. The 12-week exercise protocol will start the second week of school and continue through the middle of April. Research participants will not have any exercise session during spring break (March 16-20). Final data collection will occur during the last two weeks of school. Pre-treatment and post-treatment data collection will include a fitness assessment and blood draw. Medication usage for asthma will be monitored on a weekly basis thoughout the clinical trial. Physical activity will also be monitored monthly.