Ankles are a genetics based thing more than an environmental thing & thus exercise isn't going to do a lot. It's like having a big nose- you can lose all the weight you want but it ain't going to get any smaller! This is because ankles aren't prone to fat distribution like thighs, buttocks and stomachs. Lots of thin people have disproportionately chunky calves & ankles (aka cankles) compared to the rest of their body.
If you feel your ankles are puffy due to fluid retention then speak with your doctor or pharmacist about ways to improve this situation.

