Citation: Hackney AC, Aggon E(2018) Chronic Low Testosterone Levels in Endurance Trained Men: the Exercise-Hypogonadal Male Condition. Sportsmen and women who participate in endurance events perform a tremendous amount of exercise training. For instance, it is not uncommon for a marathon or ultra-distance runner to perform150 to 200 kilometers of intensive running per week as part of their regular training. For instance, it is not uncommon for a marathon or ultra-distance runner to perform 150 to 200 kilometers of intensive running per week as part of their regular training. Chronic exercise training to this extent results in positive physiological adaptations that are highly advantageous to the human body. Such physiological changes result in an increased human performance capacity. Yet exercise training to this extent can also place an incredible amount of stress and strain on the athlete’s body and result in unwanted physiological responses and health problems. One of the body’s physiological systems that is extremely sensitive to the stress of exercise training is the endocrine system.