I am posting this in the Forerunner 645 section. I have owned a 645 since 2018, and continue to use it. There is no dedicated section for Garmin Coach issues in the forums to my knowledge, so I am posting this here.. I have been using the Coach Jeff Galloway half-marathon program over the past several weeks (as of August 9, 2023).
A number of posters have reported that the built-in Run-Walk alert feature does not function during user programmed workouts or Coach workouts, going back 4 years across multiple watches. They expressed disappointment and/or frustration. I join them. I encountered this issue when I tried to use the Run-Walk alert feature during Coach workouts, but no alerts occurred.
There is a Connect IQ workaround for this problem that is compatible with many Garmin watches, but it is not listed as being compatible with 645.
I read a post somewhere a few days ago, which recommended using the lap button to skip past the run and cool down portions of a Coach workout, and then resuming the run, so that Run-Walk alerts become active; and then continuing to do the intended run. I tried this a few days ago and the watch behaved as expected. However, I do not know if the Virtual "Coach" even "knows" that I completed the intended run in this scenario. I suspect that it does not, but that is a guess. Who can tell me? Where can I find the information that would tell me?
A solution would be that the Run-Walk intervals would be user selectable in Garrmin Connect; a simple concept; other have mentioned this.
For me right now, the only options I see are: (1) do run-walk alerts in my head by monitoring elapsed time on the watch, (2) wear a second device to provide the alerts, or (3) purchase a watch which is compatible with the Connect IQ workaround, and use the Connect IQ workaround, which is not supported by Garmin.
Suggestions, corrections,, ideas, etc welcome. Thank you for reading this.