We agonize over minor details, which then grow into enormous problems. Check out the assembled field at the starting line of any roadrace. Being nervous before competition is natural. The symptoms vary for each sport. In baseball, pitchers do a lot of deep breathing, while hitters seemingly cannot control their urge to spit and scratch as they ready themselves to face a 90MPH fastball.
Tension is an enemy when it comes to racing.
We need to feel loose and be fluid in movement. Tight muscles hinder efficiency. Apprehension causes us to be tentative. The result can be slower times and a poor performance. Even though you may feel a slight chill in the air prior to the gun , your race effort will generate a lot of body heat.