Basically, here is a good definition of ideomotor action, per this website Ideomotor Action. 
"The term     "ideomotor action" was coined by William B. Carpenter in 1852 in his explanation     for the movements of  rods and pendulums by dowsers, and     some table turning or lifting by spirit mediums      (the ones that weren't accomplished by cheating). Carpenter argued that      muscular movement can be initiated by the mind independently of volition or      emotions. We may not be aware of it, but suggestions can be made to the mind      by others or by observations. Those suggestions can influence the mind and      affect motor behavior."
This is the explanation of why some people feel that Applied Kinesiology 'works.'  Read on at the link included and you will see plenty of examples of how many TRUE Scientists have tried to see if AK works, to try and give it credit, but to no avail.  It is no better than guessing and you shouldn't pay for something that doesn't work and can have some pretty detrimental effects on your mind and your wallet. 
