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Overtraining, Exercise, and Adrenal Insufficiency

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Abstract

Running, or any aerobic training in moderation, has a positive effect on health. There is a point of diminishing returns, where chronic stress from overtraining, which is common in runners, may be linked to problems in the adrenal gland. Overtraining Syndrome (OS) has been linked with adrenal insufficiency. There is a direct link between stress and the adrenal glands, and the physical stress of overtraining may cause the hormones produced in these glands to become depleted. Overtraining Syndrome (OS) has been described as chronic fatigue, burnout and staleness, where an imbalance between training/competition, versus recovery occurs. Training alone is seldom the primary cause. In most cases, the total amount of stress on the athlete exceeds their capacity to cope. A triggering stressful event, along with the chronic overtraining, pushes the athlete to start developing symptoms of overtraining syndrome, which is far worse than classic overtraining. Overtraining can be a part of healthy training, if only done for a short period of time. Chronic overtraining is what leads to serious health problems, including adrenal insufficiency. Severe overtraining over an extended period can result in adrenal depletion. An Addison-Type overtraining syndrome, where the adrenal glands are no longer able to maintain proper hormone levels and athletic performance is severely compromised has been described by researchers. The purpose of this review is to describe the relationship between overtraining, chronic fatigue, and adrenal insufficiency and to address the overlap in these conditions, as well as examine critical research on the relationship between the dysfunction of the adrenal axis in over trained and stressed athletes.
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... Adrenaline insufficiency has been related with overtraining. Epinephrine and nor epinephrine are related to failure in coping with stress and pain tolerance [38]. This problem has been addressed in sleep-deprived over trained athletes. ...
... Overtraining is related with adrenalin insufficiency [38]. The adrenal gland secretes adrenalin, nor-adrenalin, aldosterone, cortisol and cortisone which are critical in maintaining homeostatic metabolic environment and coping with stress. ...
... Cortisol is important for regulation of energy transfer and metabolism. Low serum cortisol is associated with ill-defined malaise, scattered thinking and focus, decreased concentration and memory and increased glucose depletion [38]. Sleep deprivation in athletes' results in cortisol imbalance that disturbs metabolism of carbohydrates, fats and proteins further disturbing the energy metabolism and utilization economy in sports population. ...
Article
Purpose Sleep is basic and common biological activity in human beings. Sleep is vital for recovery for recovering or replenishments of energy loss during daily functional activities. Sports involve expending excess energy more than required for day-to-day operations. Hence extended sleep becomes mandatory for replenishment of expended energy during sporting activities. However, real time scenario depicts athletes get lesser sleep than normally required taxing the physiological system, predisposing chronic injury and hindering sports performance. Methodology Literature search was done through PubMed Central, CINAHL, Proquest and Cochrane Central with keywords of “Sports performance AND Sleep,” “Sleep extension OR micro-sleep OR sleep deprivation AND sports.” The full-text articles or English language were analyzed and prepared for a historical review in logical order. Results Sleep deprivation has a significant impact on various physiological systems such as cardiorespiratory, nervous and endocrine system. Sleep extension has benefits in sports performance despite the variety of sports. Conclusion Sleep quality and intensity shall be borne in mind in coaching athletes before, during and after the competitions. The sleep education should be part of coaches, psychologist and team manager's training for behavior modification and fruitful team performance.
... An exercise is a form of physical stressors that have a variety of side effects, therefore, the physical exercise that is incompatible with the basic principles of exercise will adversely affect the function of the human system (6). One of the physical exercises that are not in accordance with the basic principles of training can be described as an excessive physical exercise or commonly known as "overtraining" (7). ...
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Background: Normal exercise can improve human physical abilities, but strenuous exercise can damage human cells. Strenuous exercise causes oxidative stress to the body. In order to determine the level of oxidative stress, it is important to check the levels of Superoxide Dismutase (SOD) and Malondialdehyde (MDA) in the body. SOD is the first line of defence in fighting against the oxidative stress, whereas MDA is the result of oxidative stress cell damage in the body. The sperm cell is the one that is affected by oxidative stress. This research aimed to investigate the differences in the effects of acute and chronic strenuous exercise on SOD production, MDA, and sperm quality. Methods: The research was based on experimental design with post-test only control group design with Wistar rats. Eighteen male Wistar rats were randomly divided into 3 groups (n = 6). Group I: Normal control, Group II: Rats were treated to swim for about 25-40 minutes until they were drowning for 1 day (acute strenuous physical exercise), and Group III: Rats were treated to swim for about 25-40 minutes until they were drowning for almost every day for 2 weeks (chronic strenuous physical exercise). Examination of SOD and MDA levels was done using spectrophotometry, examination of sperm quality was done by looking at the morphology, motility, and sperm quantity through the light microscope at x1000 with haemocytometer. Results: Chronic strenuous exercise significantly affects the decreasing SOD levels, increasing MDA levels, and decreasing sperm quality compared to the control group and acute strenuous exercise (P < 0.05). Conclusion: According to the results of this study, the chronic strenuous exercise effects increase oxidative stress and sperm damage.
... (5) Tetapi apabila olahraga dilakukan secara berlebihan maka akan menimbulkan masalah/gangguan kesehatan. (6) Olahraga secara berlebihan akan meningkatkan produksi radikal bebas didalam tubuh atau biasa dikenal dengan reaktif oksigen spesies (ROS) lebih banyak. Karena olahraga yang berlebihan mengalami peningkatan kebutuhan oksigen sekitar 100-200 kali lipat daripada saat beristirahat. ...
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Excessive exercise increases the production of Reactive Oxygen Species (ROS) in the body. Too much ROS will result in decreased sperm quality. The purpose of this study was to determine the impact of excessive exercise on sperm quality. The method used was experimental design with post test only control group design on the experimental animal rat Galur Wistar. Rats were given swimming activity for ± 25 minutes every day for 4 weeks. Examination of sperm quality by looking at morphology, motility and sperm count. The results of all examinations obtained a p-value <0.05, it means that the impact of excessive exercise will worsen sperm quality. Conclusion: Excessive exercise decreases sperm motility, morphology and sperm count
... (6) In addition, impaired regulation of HPA axis activity in response to exhaustive exercise-induced stress has also been observed in overstrained athletes. (7,8) These studies suggest that the alteration of the HPA axis activity in highly trained athletes could have relevance for evaluating their overtraining status and improvement of sports performance. ...
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This study investigated the effects of a drink supplement containing Momordica charantia extract from bitter melon on physical fitness and levels of stress hormones during a four week exercise training program in a hot environment. Ten male tennis players were orally administrated in a four week (100 ml, 6 times a day), and the pre and post supplementation levels of different physical fitness variables and cortisol, and adrenocorticotropic hormone in plasma were measured at four time points-before (baseline), during, and after the exercise, and on the next day of the supple mentation. The findings showed that the supplementation has significant positive effects on enhancement of physical fitness parameters especially balance (d = 22.10, p = 0.013), flexibility (d = 4.83, p = 0.015), and cardiorespiratory fitness (d = 10.00, p = 0.030). Moreover, the adrenocorticotropic hormone levels were reduced during the exercise, and the cortisol levels showed the decreasing trend during and after the exercise, which was correlated with the change of cardiorespiratory fitness (r = 0.65, p<0.05). These results indicated the possible adaptogenic effects of Momordica charantia extract intake. Based on the findings, we suggest that Momordica charantia could be used as a source of adaptogenic supplement to alleviate the exercise and environment induced stress.
... If participants answered "yes" to any health questions on the PAR-Q, they were excluded before participation. Participants with factors affecting hormone levels such as hormonal disorders, adrenal gland insufficiency, pregnancy, or individuals who smoke were excluded from this study [23][24][25]. Individuals taking oral contraceptives were excluded from the cortisol analysis (n = 2). ...
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... Regular and moderate exercise can contribute to the health maintenance, disease prevention, and stress relief (Kingwell, 2000;Reimers et al., 2012). However, exhaustive exercise or athletic overtraining may lead to excessive physical loading, and eventually persistent or relapsing fatigue, or even damages such as oxidative stress (Sen, 1995;Fehrenbach and Northoff, 2001;Popovic et al., 2012;McLeay et al., 2017), local and systemic inflammation (Woods et al., 2006;Baynard et al., 2012;Kohne et al., 2016;Liu et al., 2017), muscle damage (Woods et al., 2006;Camera et al., 2016;Liu et al., 2017), adrenal insufficiency (Brooks and Carter, 2013), or even kidney function failure (Wu et al., 2012;Lin et al., 2013), which can adversely affect the quality of people's lives. Thus, it is urgently needed to prevent and treat these changes during exhaustive exercise besides scientific diagnosis and assessment. ...
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Performance and hormones were determined in eight middle- and nine long-distance runners after an increase in training volume (ITV, February 1989) or intensity (ITI, February 1990). Seven runners participated in both studies. The objective was to cause an overtraining syndrome. The mean training volume of 85.9 km week-1 increased within 3 weeks to 176.6 km week-1 during ITV and 96-98% of training volume was performed as long-distance runs at mean(s.d.) 67(8)% of maximum capacity. Speed endurance, high-speed and interval runs averaging 9 km week-1 increased within 3 weeks to 22.7 km during ITI, and the total volume increased from 61.6 to 84.7 km. A plateau in endurance performance and decrease in maximum performance occurred during ITV, probably due to overtraining, with performance incompetence over months. Nocturnal catecholamine excretion decreased markedly (47-53%), contrary to exercise-related plasma catecholamine responses, which increased. Resting and exercise-related cortisol and aldosterone levels decreased. Improvement in endurance and maximum performance occurred during ITI indicating a failure to cause an overtraining syndrome in ITI. Decrease in noctural catecholamine excretion was clearly lower (9-26%), exercise-related catecholamine responses showed a significant decrease, cortisol and aldosterone levels remained almost constant, exercise-related prolactin levels decreased slightly. There were no differences in insulin, C-peptide, free testosterone, somatotropic hormone (STH), follicle stimulating hormone (FSH), luteinizing hormone (LH), thyroid stimulating hormone (TSH), tri-iodothyronine (T3) and thyroxine (T4). The decrease in nocturnal catecholamine excretion during ITV might indicate a decrease in intrinsic sympathetic activity in exhausted sportsmen. But it remains open whether this reflected a central nervous system incompetence.
The influence of an increase in training volume (ITV; February 1989) vs intensity (ITI; February 1990) on performance, catecholamines, energy metabolism and serum lipids was examined in two studies on eight, and nine experienced middle- or long-distance runners; seven participated in both studies. During ITV, mean training volume was doubled from 85.9 km.week-1 (pretrial phase) to 174.6 km within 3 weeks. Some 96%-98% of the training was performed at 67 (SD 8)% of maximal performance. During ITI, speed-endurance, high-speed and interval runs increased within 3 weeks from 9 km.week-1 (pretrial phase) to 22.7 km.week-1 and the total training distance from 61.6 to 84.7 km.week-1. The ITV resulted in stagnation of running velocity at 4 mmol lactate concentration and a decrease in total running distance in the increment test. Heart rate, energy metabolic parameters, nocturnal urinary catecholamine excretion, low density, very low density lipoprotein-cholesterol and triglyceride concentrations decreased significantly; the exercise-related catecholamine plasma concentrations increased at an identical exercise intensity. The ITI produced an improvement in running velocity at 4 mmol lactate concentration and in total running distance in the increment test; heart rate, energy metabolic parameters, nocturnal catecholamine excretion, and serum lipids remained nearly constant, and the exercise-related plasma catecholamine concentrations decreased at an identical exercise intensity. The ITV-related changes in metabolism and catecholamines may have indicated an exhaustion syndrome in the majority of the athletes examined but this hypothesis has to be proven by future experimental studies.