The purpose of this study was the biological effects of cycling exercise on reducing symptoms of children’s attention deficit hyperactivity disorder (ADHD) in 7 to 11 years children’s in the city of Isfahan. This study conducted in 2010-2009. Based on the CSI-4 teachers and parents scale, and using D.SM-IV diagnostic criteria, 20 patients were selected. Subjects for the 16 weeks and 2* sessions in weeks, underwent biological effect of cycling. Immediately after completion of the intervention the post test was conducted on the subject, after two weeks the follow-up test was performed again. Research results induced from analysis of variance showed one period of bike game can reduce the symptoms of the ADHD disorder is (p ≤ 0.0001). The reduction in the pre test and follow-up test track in both in parents and teachers had the same assessment (p ≤0.01).
