Tight muscle just won't loosen

Anyone have experience with a tight oblique at the upper and lower attachments? Heat seems to temporarily loosen it, but that's about it. It doesn't feel like stretching is loosening it but maybe that takes longer than expected? Any tips?

How do you know which muscle is affected, did a physiotherapist diagnose this? What do you mean by tight, do you have restricted range of movement or stiffness or what? Are you overtraining/ under recovering your core? What is your stretching regimen - do you warm up, how far do you stretch, how long for, how many repeats, how many times a day or week?

Please don't take anti inflammatory drugs unless advised by a medical professional, they can delay healing. Who recommended the heat?

Yes, the PT said it's the right oblique. A few weeks ago, it started with tightness below the last rib and into the quadratus lumborum. I continued with the core strengthening and massages but still couldn't get it to loosen. They added some pelvic tilts and that's when what I'm assuming the lower oblique attachment started acting up. When I say tight, I mean limited movement (and pain) with twisting especially/starting crunches, doing side to side reaches on your back. Warm up consists of massage and the rolling my back on the stability ball. Not sure how to answer how far I stretch. In total, the core exercises last about an hour and a half. Started again last week with once a week, this week going to shoot for once/twice depending on how tomorrow goes. I've said this to the PT, but they haven't come up with anything different other than "don't push yourself too hard if it hurts." Tried some stretching and heat yesterday. Heat loosened the muscle up temporarily but as soon as I started stretching the hamstrings, I felt that tight/contracted feeling again in the right oblique. That and after removing the heat, I felt kind of achy in the area so maybe it was too soon for heat for the surrounding muscles which just got worked on Friday. It feels so contracted that it just doesn't want to relax. Feels a bit too tender to foam roll today.

Lengthy, but they have me doing mainly 3 sets, 10 reps each of crunches, oblique crunches, side to sides, ball planks (3 sets, 15 sec holds), tba presses (60 lbs), wood chops (40 lbs), trunk rotations (50 lbs), pelvic tilt with leg extension, bridge marches, reverse crunches on the stability ball. I've been doing all this off and on for the last few months, trying to take a "break" when things act up or hurt too much.

Still feeling some tightness/pain today, but might try more yoga today to see if it helps. From previous posts, I always have a hard time not crossing that line between when you should push yourself and when you shouldn't.

anti-inflamatory (advil), heat, stretches (yoga/pilates). Repeat. It is old fashioned... also, a massage followed by drinking LOTS of water/green tea to wash out the lactic acids that have built up and then been released back into your system following the massage.

Oh! I had no idea about this. Going to start bringing the green tea with me from here on out. Thanks.