Since you're a size 2 and you were a past sprinter I assume your legs just
have extra muscle not fat.
If this is the case I would recommend you stop weight training and any high
intensity cardio in which there is a vertical component.
Weight training as well as cardio with a vertical component will maintain or
increase your legs muscle mass. Cardio with a vertical component is stairmaster,
stairclimber, steep treadmill incline has the same effect of weight training
because your muscles encounter extra resistance because they perform more work
If you want to lose muscle on your legs, you must eat a balanced moderate to low
calorie diet and jog or perform other long distance cardio for 45-60 minutes at
a time. (You've seen marathon runner's legs?) Also focus on stretching your
legs as much as you can which could cause your legs to appear slimmer.
Make sure you have enough vitamins, minerals and most importantly calcium so you
don't cause any joint or bone problems with long distance running/cardio.