The Shake Weight: Absurd Gimmick or Research Proof

By Mike Howard

The Shake Weight™ is a unique fitness device that effectively and dramatically sculpts arms, a major problem area for many women, while burning calories.”

That’s what the PR says. In reality?

Scientific Proof

It turns out that the makers of the Shake Weight have mustered up some scientific validity to their product. Or maybe not – let’s have a look. The testing parameters and methods were actually quite technical, using human simulator called the LifeMOD. Essentially a human-like model that can replicate muscular contraction and joint movement. For more information read here.

Compared to a Bicep Curl?

Before you pull out that credit card, one of the first things that should throw up a red flag is they were comparing the Shake Weight to a one-arm dumbbell bicep curl (2.5 lbs). This fact itself makes this entire “study” an absolute sham. It’s like claiming that the Shake Weight burns more calories than scratching your butt!

Sorry to give away the ending so soon, but for arguments sake, let’s have a look-see at the results.

The study analyzed the curl and Shake Weight for dumbbell curl-specific muscular activity (bicep muscle, anterior deltoid (front shoulder), lumbar region and whole body energy consumption.

Yes, the Shake Weight is Better Than a Dumbbell Curl

Predictably, the shake weight beat out the dumbbell quite substantially in all categories, prompting the Shake Weight people study’s authors to conclude the following:

  • You would have to exercise ~7 times longer with the dumbbell to expend the same total energy as the Shake Weight.
  • You would have to increase the weight of the dumbbell over ~10 times to expend the same energy in the same time as the Shake Weight.
  • The Shake Weight is a total body energizer. There is more full body muscular activation for the Shake Weight versus the Dumbbell curl.
  • The Shake Weight generates higher peak muscle forces in the main driving muscle groups.
  • The frequency of contraction is much higher for the Shake Weight.

Here are some of my conclusions

  • If you’re trying to build meaningful strength and lose body fat by doing only bicep curls with 2.5 lbs – I wish you all the best.
  • The Shake Weight works on what they call “dynamic inertia”, meaning you are maintaining an isometric position while the Shake Weight moves, forcing the muscles to respond. Of course this will cause more activation in the muscles than doing a light bicep curl.
  • Because the contraction is constant, it is going to inflate the benefits of the Shake Weight when it comes to muscle activation, as any dynamic constant resistance (ie. Traditional strength training) has points in the movement where there is more and less force being applied.
  • Comparing deltoid and lumbar muscle activation is an unfair advantage in favor of the Shake Weight, as the shoulder position is different. The Shake Weight model has the arms elevated while the dumbbell model has her elbows at her sides. By default, the anterior deltoids and the muscles of the lower back will have a greater contraction.

The Big Picture

  • When looking at these studies, it’s important to ask, “What does this actually RESULT in?” In this case, all this tells us is that the Shake Weight is superior to an activity that is virtually worthless.
  • For this study to be in any way valid, you would have to compare the Shake Weight to bigger lifts, with a higher relative resistance. Better yet, put the Shake Weight head to head against a traditional strength training program – control for other variables and show results in strength gains and fat loss.
  • While widespread muscle activation sounds great, again ask yourself, “What does that result in?”. If your goal is strength, function and fat loss, you aren’t really putting yourself at any advantage and in fact, you are putting yourself at a disadvantage when it comes to strength.


  1. BCK

    See, I disagree. I think that the goal of this product is to allow women to tone their arms without having to put in any effort at all.

    They figure (correctly) that most people are too lazy to do a traditional strenght training program, and therefore, it is appropriate to compare the results to essentially doing nothing.

    Most women aren’t concerned that they don’t have strength in their arms, as long as they are beginning to show a little definition there. And this will definitely accomplish that better than their most likely alternatives – either picking up a simple dumbell and doing a few curls or worse yet doing nothing at all.

  2. J. Foster

    Well at least it accomplishes something… I guess.

  3. Spectra

    BWA-HA-HA-HA! They’re comparing this thing to a bicep curl using a 2.5 lb weight??? Yeah, that’ll build strength in NO time…jeez, who besides Tracy Anderson recommends using a 2.5 lb weight for anything? I still think you could achieve better results just by doing pushups.

  4. John Sifferman - Physical Living

    Wow, you’ve got hand it to them. They’re trying VERY hard to make people believe this thing will help them. It’s just another excellent example that research is often a collection of facts that skirt around the truth.

    Your Big Picture was an essential part of this article. It reminds me of something I read recently about Tooth Fairy Science…

    “You could measure how much money the Tooth Fairy leaves under the pillow, whether she leaves more cash for the first or last tooth, whether the payoff is greater if you leave the tooth in a plastic baggie versus wrapped in Kleenex. You can get all kinds of good data that is reproducible and statistically significant. Yes, you have learned something. But you haven’t learned what you think you’ve learned, because you haven’t bothered to establish whether the Tooth Fairy really exists.”

    -Harriet Hall, MD