20 years after surgery I'm getting electric shock type pain when I exercise. Advice?

  I would recommend an exam by a plastic surgeon or your general practice doctor.  Not everything that hurts in that area is related the breast implants.  The exercise may have created chest wall pain due to costochondritis, which may spontaneously resolve.  It could be any number of things.

I concur that all pain in the chest area in women with breast implants is not necessarily related to the implants.  It sounds like you have had a great 20 years with your implants and hopefully will have another 20 ahead.  Since this pain has only recently become an issue and is directly related to your workouts, I would recommend trying to avoid the exercises that aggregate it for a couple weeks.  If your stomach tolerates Advil (ibuprofen), this may help significantly, especially if this is musculoskeletal pain.  If it does not resolve with that I would recommend seeing a board certified plastic surgeon who does a lot of augmentations.  Good luck. 

The most common problem causing late pain after a breast augmentation is a capsular contracture.  You need to have your breast examined by a plastic surgeon to determine the etiology of your problem.  Try to wear a supportive bra until you can be seen by a plastic surgeon.