Does running tone thighs and legs?

Yes: Certainly does. Also builds healthier cardiovascular system. Mix comfortable pace with some intervals (speed) and/or track workouts for variety and best results. Above all -- have fun doing it. Check out nearby running clubs. (USAT Level I coach) Good Luck.

Running.: Running is effective for burning fat throughout the body, which is good for tone in general. As well, running employs the muscles of the legs, especially if you run a course with hills, and as such adds muscular definition to the legs.