Hi Everyone,
I have some discoveries that I think may benefit others. Like a couple previous posters, I developed costochondritis as a result of hastiness in beginning ring work, particularly muscle-ups, ring dips, and ring supports. My sternal tendons were clearly not ready, as it resulted in costochondritis which has now been nagging me for the past year.
After the standard treatments (Fish Oil, Glucosamine, Chondroitin, MSM, heat, ice, rest, light stretching) combined with months of rest without direct chest work there was no improvement until I started using a softball to massage the tender spots on my chest and lats. Although direct massaging of the sore spots on the sternum is still quite painful, I noticed an incredible improvement almost instantaneously from massaging my lats (of all places!) and the pec minor.
Other people may have a different experience, but for what it's worth, it has been the only thing in the last year that has helped, and I can now feel my chest becoming slightly better daily from SMR work and daily pushups (which don't aggravate it in my case).
For context, my chest hurts during the following:
Back Lever
Muscle-ups
Dips
Ring Support
The more I puff out of my chest and pull my shoulders back and down, the less I feel pain. As a a result, I've put in a lot of extra pulling exercises on the horizontal plane (Inverted Rows, Cable Rows, Urgometer) to good effect.
I hope this post helps some other people suffering from the same problem!