Vivoactive 5 Strength Training change from lbs to kg

How do I change the units of measurement in the strength training app to show weight as kg not lb on the actual watch face? Measurements in the app on my phone appears to be kg but during my workouts its still showing up as lbs when I record sets and all the weights in my gym are kg, I don't want to have to do a mental conversion to lb evertime I work out!