Common causes of knee injuries in athletes include improper technique, overuse, and sudden increases in activity intensity. High-impact sports involving twisting, jumping, or sudden stops, such as basketball or soccer, put significant stress on the knee joint. Additionally, inadequate warm-up, muscle imbalances, or lack of strength in surrounding muscles can contribute to injuries. Athletes should focus on proper training techniques, sufficient rest, and strengthening exercises to minimize the risk of knee injuries during physical activity.