Overconsumption of caffeine can negatively affect athletic performance by leading to increased anxiety, restlessness, and muscle tremors, which can hinder focus and coordination. High caffeine intake may also disrupt sleep patterns, impacting recovery and endurance. While moderate doses can enhance performance by improving alertness and decreasing perceived effort, excessive caffeine can lead to dehydration and gastrointestinal issues, which are detrimental during intense physical activities. It's crucial for athletes to balance caffeine use to optimize performance without adverse effects.