There is a phenomenon that I learned in my Psych One class many years ago; it is called the Hawthorne Effect. An experiment was done at a manufacturing plant to measure the effect of changes in lighting on productivity. The workers knew they were part of an experiment- that is a key to understanding the phenomenon. The researchers found that if they turned the lights up and made it brighter that productivity increased and they found that if they made the lights dimmer productivity also increased. In short any change had a positive effect. We see this quite often in sport. We suggest that we are going to put an emphasis on speed or strength and soon everyone is commenting on how they feel faster or stronger. If you publicize it and TV commentators get a hold of it then they begin to look for and comment on how much faster or stronger looking the team or the athlete are.
Sometimes there is an actual change, but never as quickly as people are prone to comment on the change. In fact it was the suggestion of improved speed or strength that resulted in the perceived change. The lesson is that the power of suggestion and subsequent belief in the suggestion is quite strong. As coaches we need to make sure that the suggestion is supported by reality and is more than a Hawthorne effect, set a goal for what you want to improve. Elicit the power of suggestion by sharing the goal and getting everyone on board. Measure what you want to improve and keep measuring periodically to insure progress toward the goal and turn perception into the reality of measurable competition results.