Muscle endurance is significant in athletic training as it determines an athlete's ability to perform repeated contractions over a prolonged period without fatigue. Improved muscle endurance enhances overall performance in various sports, particularly those involving sustained efforts, like running, cycling, or swimming. It supports better efficiency and technique during activities while reducing the risk of injuries. Additionally, athletes with strong muscle endurance can maintain higher levels of intensity longer, which can be crucial in competitive settings where stamina plays a vital role in success.