I have it too, and am a personal trainer and practitioner of martial arts with an interest in chinese medicine. I have spoken to colleagues and teachers about it.

Here's what I've concluded on my own, put in the simplest terms I can. Hope it helps someone out:

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CAUSES:
1.) Problem is caused by inflammation of the cartilage surrounding sternum / ribs.
2.) Problem exacerbated (made worse.) by SMOKING, heavy weight training, incorrect posture such as computer/driving.
3.) Red Meat increases inflammation.


SOLUTIONS (possible):
1.) Daily stretching routine to keep limber
2.) Mentally correcting your posture whenever you can.
3.) Quitting smoking.
4.) Light exercise / weight training.
5.) 3-6 grams of Fish oil per day (check with doctor before starting)
6.) Anti-oxidants such as green tea.
7.) Finally, letting go of stress and learning to relax.

Ya my chest pop/crack started when i was 17. This is when i started to lift weights heavily. In fact I believe that i was in the gym the first time that i ever experienced it. Another guy that i worked out with said that he gets it as well. 10 years has gone by and for a while thay were few and far between. But i recently started working my out again and i hit my chest a little too hard the first time around (flys, bench press) and im going through a week of recovery here. Very sore and strained. I'm on day 4 today and wouldn't you know it, 3 CRACKS THIS MORNING! THATS RIGHT THE FIRST ONE WAS THE BIGGEST AND THE OTHERS GOT SMALLER. So i do see the connection with excessive chest strain ( not neccesarily at the gym) i'm also a bricklayer and experience some intence lifting at work as well. Kids are heavy too! lol I have never seen a doctor for it but i really appreciated the posts and suggestions on diet (protien, ant-oxidnts) and believe that these do contribute. So cheers to my fellow poppers and remember eat live and lift responsibly, and don't pick at your scabs, or intentionally agrivate your sternum. P.s those 3 pops today left me with a little added discomfort. 1 can be relieving.

i also have athsma and straining and flexing of chest due to symtoms probably contributes.

I really like your post (goodtaichi) i think we are on the same page and i've been experiencing for ten years. excellent suggestions. really!!!!!!! everyone should head this advice. its good advice no matter what the ailment.

Stop smoking. it willl kill everything inside your chest!!! and vapourize the gonja!!

I lay flat on the floor facing down and i lift my upper body back and face the roof. It gives me a good back and sternum stretch.

In my opinion this problem is related to bad posture and excess internal fat accumalated around the heart and lungs. Excess stomach area fat could also be a hindrance as it pulls our posture incorectly. Sitting incorrectly also and lying down too much is bad. Most chairs arent designed for good posture so get a good chair that fits your body ( get off that squishy sofa )- i think pilates and yoga wil help and low fat diet of poly or mono unsaturtes ( dunno???) like peanuts and olives apparantly. Cardio exercise too! I'm sure this is what it is.. Good luck too you all and lets get this sorted out between us. Doctors huh! phfff!! GKJ

I was just wondering if anyone has had this problem after having CPR done to them? This whole sternum hurting happened after CPR was done one me about 10 days ago, was just wondering how long the pain lasts.

I cry erey night im in pain dnt no how to get help drs say its all in my head my pain is so bad id tryed to kill my salf its in my nick all the way down my back in my pelvis knee hands chest feet wrist wont stop cracking no one well lisin and im dyslexic