Achilles tendonitis proper treatment & mixed advice

I am an older marathoner - 65 next week - and have done 6 since starting in 2003.  Three months ago I just did a 5 mile run an hour or so afterward my left Achilles started to hurt along the back side of my leg. I have done therapy including acupuncture, massage, physio (ice and heat) and chiro (laser and hard manipulation to break down adhesions).  My question: some people say ice is no good for anything except pain and swelling.  I agree.  But many tell me complete rest for left foot - no excercise at all until completely healed.  I do regular stretching but surely there is something else that I can do to keep somewhat fit (I have put on 20 pounds since stopping my runs) and to expedite the healing process.  I know there is not a lot of blood feeding any tendons but there has to be something else I can do.  I am also putting topical anti-inflammatory gel, Voltarene but I fear that it does not absorb through my 3 layers of skin - albeit they are thin - and into the tendon.  Please, would some expert in the field provide me with proper advice? Thank you.