Some really ridiculous fitness products have been brought to market, but the Shake Weight just might represent the cream of the crop when it comes to nonsensical exercise equipment. Based on the oxymoronic “principle” of “dynamic inertia,” the Shake Weight is alleged to give users, “lean, sculpted arms and shoulders.”
Despite the fact that the muscles of the arms, chest, shoulders and back are not moving through a range of motion the makers of the Shake Weight claim to be able to deliver muscle and strength building results. This flies in the face of just about every bit of existing legitimate scientific data on the subject of muscle and strength building.
Furthermore, the muscles of the biceps and triceps are among the smallest muscles of the body, and “exercising” them provides very little stimulus – metabolic or strength/muscle building. There is a lot to learn from the advertisement’s claim that users will, “feel it instantly.”
Just because you may “feel” something doesn’t mean that this something is beneficial or will result in a beneficial outcome, strength/muscle building or otherwise. For example, bend your index finger back as far as possible towards the back of your hand and hold it there. You feel that, don’t you? Does that “feeling” mean that you will derive a benefit from the action? Nope.
The users of the Shake Weight do not provide any of the so-called independent scientific research that is responsible for the creation of this gimmicky gadget. If this research is such a home run and illustrates that the Shake Weight is better than using dumbbells, the makers of this product should be featuring this information on their web site. I did not find any research on dynamic inertia in the vast, online databases of the National Strength and Conditioning Association or American College of Sports Medicine.
Dynamic inertia is a great example of what I call, “Vapor Research;” research touted as proof of effectiveness by an equipment huckster that isn’t provided and cannot be found.
Keeping the upper body in an isometric contraction for any length of time, while holding any implement, is going to induce fatigue. Squeeze the steering wheel of your car while you sit in traffic and your entire body will feel the effects before too long. And this is NOT a good thing.
The submaximal isometric contraction needed to hold the Shake Weight has no dynamic or functional strength building benefits. Furthermore, isometric contraction training only provides benefits to the muscle at the specific angle in which the contraction is held.
So an isometric contraction where the arms are held at a 90 degree angle will only offer strength benefits at this specific angle. Certainly, taking a muscle group/joint through a complete range of motion using dumbbells is much more efficient and effective method of training.
Save your time, money, and effort. The Shake Weight gets a, “Do Not Buy,” recommendation.