Acu-Hooping? Does it work??

etcollins95

Sooo, I'm trying to strengthen my core and I recently found an acu-hoop in my basement. I never really hula-hooped as a kid, but somehow I managed to hoop for about 30 minutes yesterday. I couldn't do it for as long today because my midsection was sore as hell.
Is this worth it, and has anyone used the acu-hula hoop and had good results? It certainly feels worth it..but is it actually working or just bruising me?