After upgrading to Google Play Service to version 6.5 many users that have an Android Wear device connected are experiencing “Connected, running sync Loop” infinite loop message. While the message varies from “Connected” to “Connected, running sync Loop”.
According to AC both messages mean the same and it occurs because Developer Options have been enabled on your phone (spoiler, this is also where the fix for the issue is but more on that later). The reason why a different message appears is because developers usually need more information this is why it shows a different message.
How to fix “Connected, running sync loop”
This message currently appears if you have any of the many different Android Wear devices (like the LG G Watch, Moto 360, Samsung Gear Live etc.) and can be fixed very easily by disabling Developer Options this can be done by navigating to Settings > Developer Options, then disconnect and reconnect your watch. For those wondering, the fact that having the developer mode enabled adds the text “running sync loop” doesn’t affect the battery or the device, it is essentially the same message as “connected”
Developer options also changes some other messages like “Waiting (number) seconds to retry connection” and “View wearable bug report”. Overall the feature is really handy to have enabled.