Has anyone injured themselves doing the 30DS

1a1a

Mainly, I read from someone that by the end of the month, their ankles were in terrible shape, now that I think about it, I can feel mine starting to crack and twinge. I don't want to stop shredding but don't want to do damage either. Anyone that's been hurt, what did you hurt? Does anyone know good stretches and exercises to minimise injury from the shred?