You're not going to believe this, but an actual study was conducted to check whether Hula Hooping (see picture below) is beneficial for weight loss.
A six-week study was conducted using a hula hoop, during which subjects (18 women) did nothing but daily hula hoop swings using a weighted hula hoop. Scientists measured differences in core strength, abdominal fat and overall fat. The results were... interesting: the subjects experienced a significant reduction in waist and hip circumference, but no change in core strength or endurance. In addition, there was no significant change in overall body fat percentage.
This indicates that the hula hooping did reduce "localized" fat deposits in the hips and waist area, but it did so by redistributing the fat to other parts of the body (not necessarily a bad thing).
Here's the link to the study (from the Journal of Strength and Conditioning Research, in case you thought this came from a non-credible source!).
As usual, any questions / comments, hit reply.