I only need ER diagram

Design a database for a fitness tracker(eg FitBit) Design must meet third normal form requirements. Provide ER diagram normalized to 3rd normal form.

Business Requirements

1.For each user record Name, age, gender.

2.Like Facebook user can add friends, the friends need to be Fitbit user.

3.The application only tracks steps walked.

4. A user can start a competitions with friends(1st degree). A user can be part of multiple competitions with different sets of users at the same time. (Define your own competitions, in the multiple of 1 day, eg, 1day, 2day, 5day and 7 days)

5.A user2 participating in a competition can add his/her friends to the competition. (2nd degree friends to the user1 who started the competition.

6.Different users can be in different time zones. EG. If user 1 is in CST and user 2 is in PST then for the user 1 the competition will end before user 2.

7.Competition participation and results should be accessible even later. 8.User will also earn medals for individual performance even when not competing in anything. The date of earning a medal or badge should be accessible. (Medals for 5000 steps, 10000 steps and 20000 steps)