You can create any event related to sports activity and invite your friends and anonymous people to join them.
You can search for sports events which are created by anonymous people or by your friend and join them.
If you think fitness can be achieved in any other way then list that way and help people and also get exposure.
Find gym in your area and find detail about gym and provide your valuable feedback.
If you think you can guide people in any sports activity then this place for you register your self and get exposure to reach people.
If You are a owner of any sports facility then this place for You,list here your place and get geographical reach.