Anxiety is a natural human response to a threatening situation.
In order to perform well in a challenging situation, you must be psychologically and physically alert. Some degree of arousal is essential for optimal performance. The problem is that when the intensity of arousal gets too high, we often begin to feel nervous and tense and experience anxiety. When psyched up, you'll be able to focus on the task at hand and performance will feel natural. You can improve your resistance to anxiety by getting adequate rest, eating appropriately, and taking care of your physical health.