Excercise machines.

haha yeah I had the same thought when I saw that re j/o.

From a fitness standpoint, it's a valid idea for certain benefits, but of course what they leave out on the commercial is that you'd have to STILL have a full weight lifting routine to build the muscle in the first place that you're shaking back and forth.
 
From a fitness standpoint, it's a valid idea for certain benefits, but of course what they leave out on the commercial is that you'd have to STILL have a full weight lifting routine to build the muscle in the first place that you're shaking back and forth.

But people wouldn't buy it if they knew it was a cure-all.