Does anyone know some good exercises to help tighten up your stomach, thighs, and your behind.

I walk on my treadmill every day, but this doesn't seem to help my stomach, thighs or my behind.

I will like to tighten up those, but just don't know what to do.

I walk on my treadmill every day, but this doesn't seem to help my stomach, thighs or my behind.

I will like to tighten up those, but just don't know what to do.