Stryd is compatible with the Vivoactive 3, Fenix 5 and 5S, meaning you can pair it as a foot pod, receive power, pace, distance, and all the other metrics that we offer (with the Vivoactive 3 you need to disable GPS). We do not list those watches in our compatible ecosystems online due to the inconsistency of Garmin's ANT+ connectivity. We have had many reports of dropouts so we are not comfortable recommending the combination of Stryd and the Vivoactive 3, Fenix 5, and 5S to our customers.
However, if you purchased Stryd and would like to use it with your 5/5S instructions to pair to your watch are the same as pairing to the FR 935 & Fenix 5X. If you have the Vivoactive 3 and would like to use it with Stryd, please follow these instructions: Stryd Zones data field for Garmin Watches
Even if you experience problems, you can still use Stryd. You will get power data on the Vivoactive 3, Fenix 5 & 5S, even if the connection is not reliable (you may see the power drop at times). Stryd will continue to record your data accurately, and you can upload your data from Stryd with the Stryd app on your phone. Stryd might record some extra time before and after your run, but you can edit this data with a Fit Tool.