Overtraining in Athletes

Abstract

Overtraining appears to be caused by too much high intensity training and/or too little regeneration (recovery) time often combined with other training and nontraining stressors. There are a multitude of symptoms of overtraining, the expression of which vary depending upon the athlete's physical and physiological makeup, type of exercise undertaken and other factors. The aetiology of overtraining may therefore be different in different people suggesting the need to be aware of a wide variety of parameters as markers of overtraining. At present there is no one single diagnostic test that can define overtraining. The recognition of overtraining requires the identification of stress indicators which do not return to baseline following a period of regeneration. Possible indicators include an imbalance of the neuroendocrine system, suppression of the immune system, indicators of muscle damage, depressed muscle glycogen reserves, deteriorating aerobic, ventilatory and cardiac efficiency, a depressed psychological profile, and poor performance in sport specific tests, e.g. time trials. Screening for changes in parameters indicative of overtraining needs to be a routine component of the training programme and must be incorporated into the programme in such a way that the short term fatigue associated with overload training is not confused with the chronic fatigue characteristic of overtraining. An in-depth knowledge of periodisation of training theory may be necessary to promote optimal performance improvements, prevent overtraining, and develop a system for incorporating a screening system into the training programme. Screening for overtraining and performance improvements must occur at the culmination of regeneration periods.

Endurance training, overtraining and baroreflex sensitivity in female athletes

“…Overtraining, resulting from heavy endurance training without adequate recovery, is also supposed to induce changes in autonomic function (Israel, 1976;Lehmann et al, 1993), Overtraining is a general term that indicates that an individual has been stressed by training and extraneous sttessors to the extent that he/she cannot perform at an optimum level after an appropriate regeneration period. (Fry et al, 1991). Over-reaching is short-term overtraining in which the restoration of performance capacity may take from several days to a few weeks.…”

“…The criteria for overtraining were (1) decreased maximal oxygen uptake by at least 2 rnl kg-1 min-I, (2) .decreased treadmill performance, (3) unwillingness to train and a feeling of inability to continue training in combination with certain overtraining signs and symptoms, e.g. mood disturbances (decreased positive feelings: energetic, helpful, calm, vigorous, relaxed, confident; and increased negative feelings: irritable, depressed, moody, fatigued, anxious, confused, excited, desperate, unable to concentrate), sleeping problems, menstrual irregularities, bad appetite, trembling hands, sweating or other psychosomatic symptoms, and (4) no illness, injury or other factors explaining the performance decrement (Kuipers & Keizer, 1988;Fry et al, 1991;Hooper & McKinnon, 1995). Five ETG athletes \vere diagnosed as being overtrained and they formed a subgroup of overtrained athletes (OAsubgroup).…”

High‐Intensity Resistance Training with Insufficient Recovery Time Between Bouts Induce Atrophy and Alterations in Myosin Heavy Chain Content in Rat Skeletal Muscle

“…Although some studies have reported loss of appetite, due to the arduous training schedule (Mackinnon, 2000;Meeusen et al, 2006), our results showed no differences in food intake between groups (data not shown). Thus, the weight loss observed in the Tr group could also be related to the reduction in plantaris muscle fiber CSA's, although other factors such as loss of motivation, apathy, irritability, and depression could be related to the weight loss (Fry et al, 1991;Mackinnon, 2000).…”

“…However, when recovery time, volume, and intensity are inadequate, they can cause a series of hormonal and physiological changes in the organism Fry et al, 2005), such as alterations in muscle fibers, a decrease in strength and an increase in protein catabolism, leading to a state called overtraining (Fry et al, 1991;Lehmann et al, 1999). Petibois et al (2003) observed that overtrained individuals presented higher amino acids and lower protein blood accumulation in response to exercise than well-trained individuals, suggesting that proteins were catabolized for amino acid supply during exercise.…”

“…Skeletal muscle adaptation to athletic training generally involves applying a progressive overload, which implies workload beyond a comfortable level to optimize performance (Fry et al, 1991;Stone et al, 1991). Unfortunately, there is a fine line between improved and reduced performance.…”