The first time I heard about Dynamic Inertia was after I had watched the Shake Weight infomercial, loaded up their website and read through the details about this curious and fascinating new piece of equipment.
This is what the official website says about this concept:
Based on a completely new workout technology called Dynamic Inertia, which ignites the muscles in your arm, shoulders, and chest.
I searched high and low for more information about this new fitness concept but could find very little. Here is what I do know: Dynamic Inertia works when you use a product like the Shake Weight which has two spring like weights on either side that create resistance when they're shaken to and fro.
This stationary movement is supposed to work your muscles very quickly as the range of motion is close to nothing. The Shake Weight ad says that you can get up to 240 muscle contractions per minute. Naturally this sounds tempting but you should remember that such a high number of contractions is mostly due to the low motion range.
Obviously, dynamic intertia works very differently than regular weight lifting does. This is more of a static workout where tension is applied to the muscles continuously. This can be useful to a point but for optimal results you do need to engage your muscles in more traditional exercises as well.
As the Shake Weight is a highly popular product these days, I have no doubt that we'll continue hearing and reading more about how it works in the near future.
I recommend that even if you choose to use this new fitness technology, that you don't forget that real results take time and come from hard work both in cardio and weight training. In addition, remember that your nutrition also plays a key role so don't depend just on one machine or device.