Trying to set LTHR and have calculated my average HR 177 over a 30 min effort run - trying to set on watch but the guide is 3-17 - how do I know what to select ? Thanks

Hello, I'm not sure what you mean by the guide is 3-17, however to manually set a LTHR, if you go to the menu, then scroll down to User Profile, then Heart Rate, then LTHR, then set it to the heart rate you calculated. You can also do this from the Garmin Connect App, or at connect.garmin.com. From the app, just go to the menu, Garmin Devices, select the 745, then select User Settings, then select Heart Rate Zones. Change Based on to % of Lactate Threshold and then set your LTHR. From connect.garmin.com select the watch icon, then go to User Settings, change Based on to % of Lactate Threshold and then input your Lactate Threshold value.