<Li> Zumba in the Circuit combines dance with circuit training . These classes usually last 30 minutes and feature strength exercises on various stations in timed intervals . </Li> <Li> Zumba Kids and Zumba Kids Jr. classes are designed for children between the ages of 7 and 11 . </Li> <Li> Zumba Gold - Toning is a toning class for older participants with goals of improving muscle strength, posture, mobility, and coordination . </Li> <Li> Zumba Sentao is a chair workout that focuses on using body weight to strengthen and tone the body . </Li>

Who invented zumba and how did it happen