Where We Stand
Even though the purveyors of Power Balance bracelets have already admitted that there is no scientific basis for any of their claims and have starting giving refunds, and there is no physical way for the bracelets to work (beyond placebo), many people still buy into the pseudoscience of bracelets that can “align your natural frequencies”, or some other such nonsense.
Enter: the placebo band. Created by the “Skeptic Bros”, this bracelet is a great way to get people to ask about your bracelet, and explain the nonsense of Power Balance and its kin. The Skeptic Bros have given us a rundown of the balance bracelet testing, seen below, exposing how a little application of physics is all you need for people to fork over $60.
Beyond the dissection of their misleading tests, I have done some calculations to show that the only thing fooling the masses is the direction of force. Nothing more. You can find the calculations in the section titled “Physics of the Con.”
How Power Balance Cons You
Here’s a rundown of everything that the salesman will throw at you. Become your own Power Balance con-man (for science)!
Ask your subject to stand with feet together with their right arm outstretched in front of them, palm down. Have your subject twist to the right, from the waist, as far around as they can go (Fig. A) When they reach the point where they stop, place the Placebo Band on the back of their out stretched hand, or snap it on their wrist, and ask them to go a bit further around (Fig. B) Amazingly they will be able to!
The rationale is that the person will not actually go as far as they can go when they twist around. Once their body stops twisting, it will naturally twist back towards a comfortable position without the person knowing. It is then easy to twist again a bit further.
A (less convincing) variation on this is to have them touch their toes, pause, put the band on their back and ask them to go lower.
Without Placebo Band ask you subject to stand with their feet together with arms at the their side. Have them turn one hand palm out and cup their fingers up. Stand side by side with you friend put your fist in their cupped hand like you are trying to pass them something without everyone noticing. Tell them to ‘try’ to resist you (implying that they won’t be able to). Push down and slightly away from them (Fig. A) this should pull them off-balance. Now have them put on Placebo Band and repeat the test telling them to resist, except this time push down and slightly towards your subject (Fig. B). Amazingly it should be impossible to unbalance your friend!
The rationale behind this one is similar to the next two tests, “the scarecrow” and “you’re nicked”, and is explained below in the “Physics of the Con” section. As we will see, a simple change in the direction of force makes all the difference.
Without Placebo Band ask your subject to stand, arms outstretched to either side, balancing on one leg. In the same way as the The Deal push down and slightly away (Fig. A) while telling your subject to ‘do their best’ to resist you. They will fall off-balance easily. Then, with Placebo Band on your friends wrist and a hand firmly on the shoulder push down and slightly toward your subject. Amazingly your friend will be able to stand strong!
(Though not illustrated, this effect is best practiced with one hand on your friends shoulder – this will give you more control.)
Now you have their trust, lock it in.
Without Placebo Band ask your friend to stand in front of you facing away, feet together, with hands behind their back, fingers interlaced, palms up. Stand 60-90cm (2-3ft) behind your subject and push down and slightly away (Fig. A). When they fall backwards DO NOT let them hit the ground. Protect their head!
Then, with Placebo Band on your friends wrist repeat the test only this time push down and slightly towards your subject (Fig. B). Amazingly they will not fall over!
[Via the SkepticBros]
Why are these tests so effective at selling people pseudoscience? I can tell you what it isn’t. It isn’t “vibrations” or “frequencies” or “auras” or “alignments”, or any other buzzword meant to make it seem like these bracelets have some basis in science. It’s the application of a little physics.
Physics of the Con
Let’s imagine that a balance bracelet salesman approaches you to test your balance, and hopefully sell you some junk. The diagram below illustrates “The Scarecrow” position seen above.
To see why the direction of force makes all the difference, we have to consider the moment acting on the person. A moment is a description of the “twisting” or “rotational” force applied at a point, which is a function of how a force acts on a point at a perpendicular distance. It is this moment that will determine which position a person is easier to tip in, and not any magical “vibrational alignment.” Let’s do a little math, assuming that the person’s tipping point is at their foot (point A):
I’ll save you the engineering specifics, but 64 ft-lbs is the amount of twisting or rotational force (using the arbitrary angle and magnitude) that will be applied at the foot of the person taking the test (the tipping point/point A), assuming the length of their arm is 3 feet, and their height from their shoulder is 6 feet. This can be quite a large amount of force, depending on the pushing being done, and it could surely unbalance you. But the tester will then put the bracelet on you and test your balance again, this time changing the angle of the force being applied, as seen in the diagram below.
Only 21 ft-lbs, which is about one third as much force than was applied to you earlier (the negative sign means that the direction of rotation is the opposite). Being that you don’t want to be unbalanced again, are trying a lot harder to resist, want the bracelet to work, and are using more muscles (your core muscles) to resist a force significantly smaller (and in a direction that activates the larger core muscles), an impression is given that the bracelet had some effect.
The reality is simple physics. The way that the balance bracelet salesmen “prove” their effectiveness is merely taking advantage of forces, moments, and muscles. It has nothing to do with “frequencies” and “vibrations” and everything to do with statics. Nothing magical here.