running improves every part of your body. if youre looking to tone your stomach you need to run too. sit ups alone do nothing but build the muscle UNDER the fat, making your stomach appear even bigger.
running also is not the best exercise for u, its not good for ur joints, but i run anyways. but what they said is true. biking tho i think is even better exercise
It tones your calves, thighs, butt, and arms if you run properly. It gives all over weight loss though that includes your stomach.
it actually tones everything but it mainly does ur butt thighs stuff like that butt it sheds everywhere even tummy