During the building process, you will be unable to adjust the name and description of the workout. Both of these are auto-generated. The reasons are twofold. First, it keeps people from building duplicate workouts. If you attempt to build a workout that already exists on the BTWB, the site will return you that workout. Second, it helps the site, and ultimately you, find workouts more easily. In addition, it keeps workouts standardized across the site.
Gym admins will be able to attach a custom title to a given workout that only it's members will be able to see. The default name will remain the same though for the rest of the site's users.