Overtraining Syndrome



Overtraining Syndrome


Elizabeth Gannon

Thomas M. Howard



INTRODUCTION



  • Overtraining has been described and has been well known to athletes and trainers for decades. In 1923, Dr. Parmenter described overtraining as “a condition difficult to detect and still more difficult to describe. Evaluation should focus on training load, nutrition, sleep, rest, competition stress, and psychological state” (14).


  • There are multiple hypotheses on the cause of overtraining. There continues to be research on overtraining to further define the condition and pathophysiology and identify markers for diagnosis, treatment, and prevention.


  • Overtraining, if left unrecognized or untreated, can result in injury, poor performance, and early retirement.


  • Overtraining syndrome is a condition that arises along a continuum of fatigue.


  • The diagnosis of overtraining syndrome is one of exclusion and often requires an extensive workup of the athlete.


  • Treatment of overtraining syndrome is rest; however, it often requires a multidisciplinary approach involving the physician, trainers, nutritionist, and often, a sports psychologist.




PHYSIOLOGIC CHANGES WITH TRAINING


Immunologic



  • Decreased salivary immunoglobulin A (IgA)


  • Increased white blood cells (WBCs), lymphocytes, natural killer cells, and polymorphonuclear cell (PMN) activity


  • Transient decrease in T helper/T suppressor (Th/Ts) ratio


  • Decreased serum glutamine


Endocrine



  • Increased testosterone proportional to exercise intensity and muscle mass stimulating glycogen regeneration and protein synthesis (anabolism).


  • Transient increase in cortisol relative to the duration and intensity of exercise. The stress response (catabolism).


  • The ratio of free testosterone to cortisol (FTCR) represents the balance of catabolism and anabolism. A 30% decrease in this ratio may suggest inadequate recovery or overreaching (5).


  • Norepinephrine increases before exercise (anticipation) and early in exercise, stimulating lipolysis.


  • Epinephrine increases proportional to exercise intensity.


  • Decreased sex hormone binding globulin (SHBG) production with intense exercise.


  • Suppression of pulsatile secretion of gonadotropin-releasing factor (GnRH), probably affected by stress and poor nutrition.


  • Growth hormone peak secretion at night and with exercise ˜50% [V with dot above]O2max, blunted response with intense exercise.



EPIDEMIOLOGY



  • Overtraining affects 5%-15% of elite athletes at any one time and as much as two-thirds of runners during an athletic career. It may also be seen in amateur athletes.


  • More commonly seen in endurance events, such as swimming, cycling, or running. Overtraining in powerlifters is probably different.


  • Susceptible athletes include highly motivated, goal-oriented individuals; athletes who design exercise programs by themselves; and athletes that tend to be focused, conventional, and conservative.


HYPOTHESES

May 22, 2016 | Posted by in SPORT MEDICINE | Comments Off on Overtraining Syndrome

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