Are the shaking belts efficient for fitness? and when should we use them?

hi

i have an electrical shaking fitness belt .i want to know are they useful for fitness and losing fat .and also i want to know which time is better to use? after exercises? or before? and are they efficient without doing exercises?Are the shaking belts efficient for fitness? and when should we use them?i dont think its going to do much... except make u look at urself jiggle. i have been doing this for a while-%26gt; http://www.youtube.com/watch?v=WaL03V3YN鈥?/a> and its helped me. i just added it to my diet and went from there. maybe it will help u too (but i wld definitely say diet wld benefit u more than a shake machine)