Try the place just East of Don Andres across Alejo Martinez on Calle D. Stern in the little U-shape center where they do laundry. If you speak Spanish tell them your problem with your 'piernas'. I go there when I'm sore, and I have a bad right leg and hip too. Usually I go to sleep during massages or at least as soon as I get home.
Only 500 pesos plus tip - as I know the girls survive on tips.
The older I get the more massage seems to help.
I have had them on the beach and usually sand is on my legs and is irritating plus a pain to go to the beach if that's all you want is a massage.
Oh they also do pedicure - since I'm a little big around the middle I get that once a month too.