Lifting Weights and Rotational Inertia

In physics we are now studying Rotaional and circular motions. I learned that theres a difference btw circular motion and rotational motion. Circular motion has a axis outside the object and a rotational has an axis within the object. The coolest thing about this concept is the rotaional inertia which is the property of an object to resist changes in its Rotational motion. It depends on two things; its mass and the distribution of the mass. For example, this weekend my sister wanted to prove that she was strong so I told her to hold to rotate the bar two different ways and she'll prove to be smart as well. So she held the bar in the middle and rotated it up and down. Then she held the bar at its ends and rotated it. I asked her which one was harder and she said the one in the middle but i told her it has more rotational inertia. Haha and she was like "ok" in a confused way. Then i told her she'll learn about it a couple years from now. hahaha Anyways, ill upload her pictures later bc my internet wasn't working on the weekend.=)