Personal data collected by fitness trackers can leave users open to security and privacy threats, often without their knowledge. We explored whether increasing user awareness of security and privacy risks might prompt users to take action to protect their personal information. First, we conducted an online survey with 212 fitness tracker users to understand participants' knowledge, attitudes and behaviours related to security and privacy with their fitness trackers. We designed information posters based on our results and conducted a second in-person study with 34 participants. Overall, we found users have distinct sharing preferences for specific types of data and for specific recipients; and they exhibit contradictory behaviour. We demonstrate that it is possible to change fitness trackers' users reported privacy behaviours by showing them information posters. Overall, our findings show fitness tracker users require a greater awareness of protection practices and can benefit, if provided with information.