Calf mobility (Day 9) injury

I performed the calf mobility stretches yesterday without any pain at all, but by evening there was some soreness in my left achilles and this morning I have serious pain and a limp. I'm not too upset by the injury, but if I didn't experience any pain during the stretches, how do I keep from re-injuring my achilles? 

Any tips on what I did wrong?

(FYI, I do have hyper-extending joints which may have played a role).

Thanks.

Hi Sean,

If you have not used your calves/achilles for some time, the first time you do so can lead to some rather spectacular muscle soreness.

Greatly reduce the intensity with which you approach your calf mobility.  All should be fine in a week or so.

Yours in Fitness,

Coach Sommer