One of the issues that have risen the past few decades due to excessive use of technological advances is internet gaming disorder (
IGD). Past research has concluded that there is a negative association between
IGD and exercise as well as a positive association between
IGD and
attention deficit hyperactivity disorder (
ADHD). However, the existing studies on these subjects are scarce. Furthermore, researchers have showcased that symptoms of depression, anxiety and stress are positively associated with
IGD and
ADHD but negatively associated with exercise. Consequently, maybe these symptoms mediate the relationships between
IGD, exercise and
ADHD. The purpose of the present study is to investigate the relationship between
IGD and exercise as well as between
IGD and
ADHD. A correlational study was conducted on 515 adults through Google forms. The Internet Gaming Disorder Scale-Short-Form was used to detect
IGD symptoms, the Leisure-Time Exercise Questionnaire was utilized so as to evaluate participants' leisure - time exercise habits, and the Barkley Adult
ADHD Rating Scale was used to assess
ADHD symptoms. Furthermore, the Depression, Anxiety and Stress Scale-21 was utilized to evaluate symptoms of depression, anxiety, and stress. It was found that there is a negative correlation between
IGD symptoms and leisure time exercise as well as a positive correlation between
IGD symptoms and
ADHD symptoms. Moreover, when taking all the variables that were examined into consideration, it was indicated that inattention symptoms and impulsivity symptoms were significantly associated with
IGD symptoms whereas symptoms of depression were partially and significantly mediating the association between
IGD symptoms and Attention deficit as well as the association between
IGD symptoms and Impulsivity. The findings of the current study suggest that people who deal with
IGD symptoms tend to exercise less on their free time. Additionally, people with more
IGD symptoms display not only more
ADHD symptoms, symptoms of inattention and impulsivity specifically, but also more symptoms of depression. Therefore, clinicians should evaluate the possible coexistence of such symptoms when treating people with
IGD, in order to prevent as well as treat more efficiently
IGD and its consequences.