Overtraining syndrome in athletes
- Thomas M Howard, MD, FACSM
Thomas M Howard, MD, FACSM
- Cary, North Carolina
- Section Editor
- Francis G O'Connor, MD, MPH, FACSM
Francis G O'Connor, MD, MPH, FACSM
- Section Editor — Sports-Related Injuries; Symptom Assessment and Physical Examination; Medical Issues Related to Sports and Exercise
- Professor of Military and Emergency Medicine
- Uniformed Services University of the Health Sciences
Overtraining was recognized as early as the beginning of the 20th century. In 1923, in an article on training college athletes, D.C. Parmenter warned: "Overtraining or staleness is the bug-a-boo of every experienced trainer" . Many contemporary athletes train hard and risk injury to achieve an advantage over their competitors. Among high level athletes, large training volumes and high intensity are required to achieve incremental gains in performance, and such training may in turn increase the athlete's risk of injury and fatigue.
Overtraining syndrome (OTS) is a complex clinical disorder identified in the athletic population that represents a maladaptive response to training. While studies to date have focused on endurance sports, OTS has been described in sports that rely on power and anaerobic performance. It addition, it is reasonable to assume that members of occupations requiring intensive physical training in combination with other biologic, psychological, and social stressors (eg, firemen, police officers, military personnel) may suffer from OTS. A term frequently associated with OTS is "burnout." While burnout may develop in athletes, it is found in numerous occupations, including healthcare providers; OTS is thought to be the result of an imbalance between exercise and rest, while burnout is secondary to mental overload.
The etiology, epidemiology, presentation, and management of overtraining syndrome will be discussed here. Specific injuries that may be sustained as a result of overtraining are reviewed in the topics devoted to that injury.
DEFINITIONS AND PRINCIPLES OF ATHLETIC TRAINING
In order to understand overtraining, one must first understand the basic terminology and principles of training.
Athletic training can be defined as specific, repeated body movements performed according to a planned program in order to improve or maintain one or more elements of physical fitness (eg, speed, endurance, strength, power). Intense athletic training is intended to disrupt the body's homeostasis, temporarily causing neuromuscular fatigue. Immediately following such a stress, performance declines, but given adequate rest and nutrition, the body regenerates and re-establishes homeostasis at a new level better able to cope with the activity that initially disrupted homeostasis. Once the body adapts, the previous training stress is no longer capable of disrupting homeostasis and stimulating further adaptation. Additional progress requires greater stress. This is known as the overload principle, and the body's response to such training is referred to as overcompensation or super-compensation.
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- DEFINITIONS AND PRINCIPLES OF ATHLETIC TRAINING
- TERMINOLOGY OF OVERTRAINING
- CURRENT THEORIES AND PHYSIOLOGY
- CLINICAL PRESENTATION
- DIAGNOSTIC EVALUATION
- DIFFERENTIAL DIAGNOSIS
- Nutritional deficiency
- Psychological problems
- Other medical problems
- PREVENTION AND MONITORING
- Prevention measures
- Suggested approach to monitoring
- Psychological and recovery monitoring
- Physiologic markers of overtraining
- Biochemical markers of overtraining
- SPECIAL CONSIDERATIONS IN THE YOUNG ATHLETE
- SUMMARY AND RECOMMENDATIONS