Thanks for the submission. This is a cute design and I kind of like the attitude she shows, but she looks a little too much like a skinny Bratz character than a defined, strong chick that works out hard at the gym. I'd like to see more of her, including her knee-high socks and she needs to be more defined, with muscles. Not bulky with muscles. But, defined with muscles.
This character could also be doing something with a barbell to help show how strong she is.
For reference, look at these images of CrossFit chicks:
https://www.google.com/search?q=crossfit&source=lnms&tbm=isch&sa=X&ei=z9t7U8GIGurksASprICYAw&ved=0CAkQ_AUoBA&biw=1383&bih=630#facrc=0%3Bcrossfit%20women&imgdii=_&imgrc=_She doesn't have to have six-pack abs, but she should be defined muscularly and not a waif.
I actually really like the feel of her attitude and the look and feel of the overall design so far, but the character needs some work to look more athletic.
Thanks!