The effect of beliefs on maximum weight-lifting performance

Abstract

The role of beliefs based on perceived external cues in determining maximum-strength lifting performances on a resistance exercise machine was examined. The task in question was a single maximum inclined bench press performed with other strength tests once per week for 6 weeks. Forty-eight college male volunteers engaged in physical education activities unrelated to strength development were randomly assigned to three groups. All subjects lifted for 3 weeks to establish baseline strength before the resistance settings were deceptively altered for testing under the treatment conditions. In one treatment the resistance was altered so that more weight was being pressed than the subject believed. Another treatment involved lifting less weight than the subject believed, and the third treatment was performed while subjects were denied direct knowledge of weight being pressed. A control group lifted each week without any manipulation of the resistance. Treatment groups were counterbalanced for order effect. Analysis of variance of mean differences for both groups and treatments showed significant (p <.05)main effect for treatments. A posteriori comparison revealed significantly higher strength performances when the resistance was greater than the subject believed. This performance difference was attributed to subjects' attempts to remain consistent with self-expectations based upon environmental cues.