Well it depends what your priorities are. If that priority is building muscle mass, and you really want to get in your four workouts a week, then boxing is going to come second. If you see your lifts suffering, or you’re too beat up in the weightroom, cutting back on boxing would be a good idea.
But if you’re finding you can handle the workout pretty well, then stick with it - although be careful about the volume you’re doing and the intensity you’re hitting it with.
Boxing is #1 for me, so if I’m skipping something it’s weight room work, and I’m basing the days I lift around my days in the ring. I can’t handle doing 3-4 days of boxing and more than 2 days of lifting, but if you can without hitting a wall, go for it.
Keep in mind that it may become too much for you, and you’ve got to keep an eye on it…especially if you go full bore boxing. Obviously we can do full boxing workouts every day and with intensity (as fighters do) but I’ve found that if I really go all out, my lifts are gonna suffer so I’ve got to cut the volume with the weights back.
This is my log.