Yes, epsom salt baths can work wonders since your body is absorbing all of that magnesium which helps with muscle tissue health as well as nerve function. And post workout is definitely a good time to get in some mobility work I know I take a few minutes before I’m actually warmed up and I don’t have to fight my muscles as much after a workout. Like I said doing it before a workout will help with efficiency while doing it post workout will lead to greater gains since you already have increased bloodflow from the workout. Flexibility becomes much less of a hassle ha.