I am suffering from the same thing. A couple of months ago I felt a slight cramp in my lower calf after a run, then a few days later while running downhill I had this intense pain.
after walking home I checked online and realised it was my Achilles and not my calf muscle.
I initially took 2 weeks off, then ran only once a week. At first I struggled and had to keep resting. I am now up to 7miles and looking into sneaking another run in, in the same week.
My advice is rest and slowly get back into it. My pace is slow at the moment, but I'm managing to get around.
before adidas I was told to try asics 3020 trainers. To this day I'm sure that's what screwed up my achilles
Have a look at the saucony range. I ran with adidas for years but was dissapointed with the adidas boost.
i originally wanted the saucony kinvara but was persuaded with the boost.
when I changed over I would never go for anything else.
i alternate between the kinvara's and the virrata's.
I was checked and told that I overpronate and should buy trainers that correct this. But learned that you are better off improving your running form.
I now suffer from very few injures.
Try different trainers and find the best that suits you. Do not go by what the shop assistant tells you.
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