j h says:

i have had this off & on for years. 1st time i diagnosed myself as it being muscle, but then got worried so checked with doctor too. he did blood workup and etc, and was 100% certain it was muscle, not heart. it eventually went away, but about a year later started having dull low end chest pain & i swore it had to be heart. it would come and go. sometimes lasting up to an an hour & sometimes a whole day with nothing. i could run, climb, and bike fine & never any pain when being active. finally after 2 years of this i awoke in morning with BIG pain and spread out from heart. Got terrified, went to ER & got full testing – blood (twice at 3 hour interval), EKG, and xrays. Verdict? I have super strong heart with perfect rates and xray appearance & blood results. Not just ok, perfect. So what was it? all muscle from a couple hours painting a small room ceiling & then following day putting up a ceiling fan… very odd, as i have beat my body much worse and much longer work without any chest pain like that. They gave me muscle relaxant & something to reduce muscle swelling & within hours no heart pain & only neck muscle & center chest muscle pain… Always good to check even if just doing general yearly exam, but muscle abused can happen with smallest activity & result in strange areas of pain, then worry or stress makes it much worse. With that said, there are many different types of symptoms for many different types of heart problems and being iin shape cant alwasy deter prolems especially unknown genetic or freak variances with heart.
I knew a guy I worked wiht in great shape at 27 & died instantly on chair watching tv. Had unknown heart artery problem no one ever knew about and just decided one day to burst. He was dead so fast he looked like he was still watching tv.