Stress can cause physical symptoms, including chest tightness, due to the body's natural fight-or-flight response. When you're stressed, your muscles may tense up, your breathing can become shallow, and your heart rate may increase—all of which can contribute to a sensation of tightness in the chest. This is usually temporary and tends to subside as your body relaxes. However, if chest tightness persists or is accompanied by other symptoms like shortness of breath, dizziness, or pain radiating to the arm or jaw, it's important to seek medical attention to rule out any serious conditions.