1.  The hams can be involved in stabilization of the pelvis if other muscles are not working like the glutes, or if you have incorrect posture, or similar.  If you become dependent on the hams to stabilize your pelvis, then they can get SUPER tight and overworked and especially under high load or loads over time/distance.  I’d have to look at your posture and also whether you are bracing with your ab and back muscles or are generating intrabdominal pressure to help counteract the need for the hams to be so involved.

2. another thing you could look at is that something on the other side of the hams is not activating in those movement patterns to turn the hams off.  in this case, it could be any one of the hip flexors.  so for say KB swings, if you do not pull yourself down strongly with the hip flexors, then you could cause the hams to never get the signal to shut off. over time they will just stay tight and then you’ll feel them after the workout.  for this, you would practice “clamshelling” your body down against your top of quads and pulling down strongly with your hip flexors every time you have a movement that requires this.  So pull yourself down into loading up for the deadlift for example, or pulling yourself down when the KB swing goes between your legs instead of being lazy and relaxing yourself down.

if this is the case, then the classic posterior chain floss with banded distraction to the rear, and doing it on the floor could be something that will help a lot especially if you flex the quad strongly like Kstarr says.

food for thought.