Traditionally having an extra week to prepare for a team has gone well for teams. Since 2014, the Miami Dolphins are 3-2 so it is not a given that teams will win after their bye week.
Last year Miami lost to the Colts out of the bye week. Since 2014 they are 3-2.
Brad Perniciaro of Cheatsheetwarroom.com posted analytics for the NFL and the leagues bye-weeks that bring some of this into focus. He has a list of each teams win/loss record after a bye week since 2014.
The Dolphins will play the winless Washington Redskins next week and will try to improve to 4-2 after a bye.