• Journal of the Korea Convergence Society
• /
• v.8 no.11
• /
• pp.461-476
• /
• 2017

The purpose of this study was to investigate the existing theories related to overtraining syndrome and to examine the mechanism of overtraining syndrome from the viewpoint of brain science by examining domestic and foreign literature related to the relationship between overtraining syndrome and brain neurotransmitter. The aim of this paper is to provide basic data that can improve the understanding of the mechanism of overtraining syndrome and the role of neurotransmitters and neuromodulators. The results of this study and a number of hypotheses about the overtraining syndrome were proposed, each with strengths and weaknesses. Similar symptoms that occur when the concentration of serotonin in the neurotransmitter increases are related to signs and symptoms of overtraining syndrome. However, it has not been validated to date because it can not distinguish the mechanism of the mediator between the central nervous system and the peripheral nerves. This study suggests that the mechanism of overtraining syndrome will provide important basic information to understand the complex causes of overtraining syndrome through the interaction of existing theory and brain neurotransmitter. Although there has been a lack of studies on the mechanism of overtraining syndrome and brain neurotransmitters so far, we hope that this study will provide an opportunity for more and more people to broaden their understanding of overtraining syndromes.

• Journal of Life Science
• /
• v.25 no.11
• /
• pp.1324-1330
• /
• 2015

The present study was performed to analyze and review the physical and immune responses to overtraining syndrome in humans. Overreaching refers to the initial phage of overtraining syndrome and has been known as a physical fatigue which is mainly from metabolic imbalance. It has been known that overtraining also results in a loss of adaptability which may lead to an attenuation of exercise performance, sleeping disorder, central fatigue, neurohormonal changes, difficulty recovery to physical stress, and immunological changes. Additionally, overtraining syndrome is characterized by persistent fatigue, poor performance in sport due to the prolonged and strenuous physical training. Also, previous studies reported that endurance athletes experienced a high incidence of URTI during intense training and the post training. And also, high-performance athletes reported that suppression of cell mediated and anti-body mediated immune function. NK cell numbers were also reduced in the period of overtraining syndrome. Major components of prevention and treatment for the overtraining syndrome are screening, education, and detraining. Furthermore, the combination of these prevention and treatment strategies will be much helpful. Therefore, the current review will be helpful for athletes and individuals who are at the risk of overtraining syndrome.

• Journal of Digital Convergence
• /
• v.15 no.8
• /
• pp.501-509
• /
• 2017

The purpose of this study was to review the effects of the physical fatigue induced by overtraining on cognitive information processing and emotional change of athletes by neurophysiologic study. And to provide basic data for the athletes and coaches in the sports field to improve understanding of the overtraining symptoms from the brain physiological point of view. We reviewed the domestic and international academic materials and research reports published in the last 20 years using electronic databases and examined the literature that is consistent with the purpose of this study among the retrieved documents. Based on the reviewed literature, we examined the cognitive information processing and emotional change of the athlete according to the training, and overtraining can accumulate the fatigue of the body, which can cause severe side effects in terms of cognitive ability and emotional ability of athletes as well as deterioration of performance. The study using P300 and EEG cerebral hemispheric asymmetry difference indices also confirmed the possibility of a new approach to understand psychological and physiological effects of overtraining on information processing and emotional changes.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.19 no.4
• /
• pp.574-579
• /
• 2009

There have been much difficulties to construct an optimized neural network in complex nonlinear regression problems such as selecting the networks structure and avoiding overtraining problem generated by noise. In this paper, we propose a stepwise constructive method for neural networks using a flexible incremental algorithm. When the hidden nodes are added, the flexible incremental algorithm adaptively controls the number of hidden nodes by a validation dataset for minimizing the prediction residual error. Here, the ELM (Extreme Learning Machine) was used for fast training. The proposed neural network can be an universal approximator without user intervene in the training process, but also it has faster training and smaller number of hidden nodes. From the experimental results with various benchmark datasets, the proposed method shows better performance for real-world regression problems than previous methods.

• ETRI Journal
• /
• v.33 no.6
• /
• pp.914-923
• /
• 2011

This paper concerns robust and reliable speaker model training for text-independent speaker verification. The baseline speaker modeling approach is the Gaussian mixture model (GMM). In text-independent speaker verification, the amount of speech data may be different for speakers. However, we still wish the modeling approach to perform equally well for all speakers. Besides, the modeling technique must be least vulnerable against unseen data. A traditional approach for GMM training is expectation maximization (EM) method, which is known for its overfitting problem and its weakness in handling insufficient training data. To tackle these problems, variational approximation is proposed. Variational approaches are known to be robust against overtraining and data insufficiency. We evaluated the proposed approach on two different databases, namely KING and TFarsdat. The experiments show that the proposed approach improves the performance on TFarsdat and KING databases by 0.56% and 4.81%, respectively. Also, the experiments show that the variationally optimized GMM is more robust against noise and the verification error rate in noisy environments for TFarsdat dataset decreases by 1.52%.

• IMMUNE NETWORK
• /
• v.5 no.2
• /
• pp.117-123
• /
• 2005

The immune response to any stimulus is complex, requiring coordinated action by several types of cells in a tightly regulated sequence. Thus, a physical stress such as exercise may act at any number of points in the complex sequence of events collectively termed the immune response. Although exercise causes many propound changes in parameters of immune function, the nature and magnitude of such changes rely on several factors including the immune parameters of interest; type, intensity, and duration of exercise; fitness level or exercise history of the subject; environmental factors such as ambient temperature and humidity. Although regular moderate exercise appears to be important factor for increasing immunity, Athletes are susceptible to illness, in particular upper respiratory track infection, during periods of intense training and after competition. In addition, in elite athletes, frequent illness is associated with overtraining syndrome, a neuroendocrine disorder resulting from excessive training. Through this paper, we want to investigate the effects of exercise on the immunosuppression such as exercise induced lymphopenia, asthma, anaphylaxis, URT (upper respiratory track), and TB (tuberculosis) infection. and also, we want to suggest a direct mechanism, protection and therapy of exercise induced immunosuppression.

• Journal of the Korean Society of Physical Medicine
• /
• v.15 no.1
• /
• pp.11-18
• /
• 2020

PURPOSE: This study was to investigate examined the differences in the autonomic nervous functions of elite female judo athletes according to their performance by measuring the heart rate variability (HRV). METHODS: Sixteen elite female judo players participated in this study. The participants were divided into a high performance and low performance group according to the results of their competitions. The HRV (mean heart rate, SDNN, RMSSD, TP, LF, HF, LF/HF ratio) was measured in the resting status. A t-test was used to compare the two groups, and bivariate logistic regression analysis was performed to determine the HRV elements that affect performance. The data were analyzed using IBM SPSS Statistics ver. 24.0 (IBM Co., Armonk, NY, USA). RESULTS: The mean heart rate was higher in the high performance group (72.88) than in the low performance group (64.75) (p=.049). The LF/HF ratio was higher in the high performance group (3.43) than in the low performance group (0.83), and the results were significant (p=.038). No HRV elements having a significant effect on the performance were observed. CONCLUSION: This study showed that the activity of the sympathetic nervous system was dominant in the high performance group in the resting status than in the low performance. The high performance group is believed to be in the overtraining status who experience more stress.

• Korean Journal of Exercise Nutrition
• /
• v.16 no.1
• /
• pp.19-26
• /
• 2012

The purpose of this study was to analyze the effects of intake of aronia, montmorency, and Prunus mume on 10 km endurance exercise by investigating changes in blood lactate, ammonia, creatine kinase (CK), and lactate dehydrogenase (LDH), and eventually to recommend them as ergogenic aids, which are effective for recovering from exercise fatigue and muscle damage. The subjects were divided into a P. mume intake group, an aronia intake group, a montmorency intake group, and a control group. Blood samples were taken from the brachial vein at rest, and at 0, 30 min, and 24 hr after running to measure recovery status. All data were analyzed by a two-way repeated-measures analysis of variance using SPSS. The results are summarized as follows: The changes in blood ammonia and LDH concentration following 10 km of running were not significantly different among the groups. However, lactate and CK recovery ratio increased significantly in the aronia and montmorency groups compared to those in the P. mume and control groups. In particular, CK concentration was significantly different in the montmorency group compared to that in the other groups. These results suggest that the effects of aronia and montmorency are associated with improved recovery from muscle fatigue and damage induced by highly intensive exercise, endurance exercise, or overtraining. In particular, montmorency is recommended as an ergogenic aid to inhibit muscle pain resulting from high-intensity endurance exercise.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.16 no.4
• /
• pp.350-357
• /
• 1991

A speech recognition system based on a neural network, which can be used for telephon number services was tested. Because in Korea two different cardinal number systems, a koreanic one and a sinokoreanic one, are in use, it is necessary that the used systems is able to recognize 22 discret words. The structure of the neural network used had two layers, also a structure with 3 layers, one hidden layreformed of each 11, 22 and 44 hidden units was tested. During the learning phase of the system the so called BP-algorithm (back propagation) was applied. The process of learning can e influenced by using a different learning factor and also by the method of learning(for instance random or cycle). The optimal rate of speaker independent recognition by using a 2 layer neural network was 96%. A drop of recognition was observed by overtraining. This phenomen appeared more clearly if a 3 layer neural network was used. These phenomens are described in this paper in more detail. Especially the influence of the construction of the neural network and the several states during the learning phase are examined.

• Journal of Life Science
• /
• v.28 no.5
• /
• pp.621-626
• /
• 2018

We introduced the physiological responses of aging, active aging and also suggest the impact of physical exercise on body health status and elderly immunity. In this purpose, we searched the Pub Med data base for the articles (include our experimental papers) and review papers having the terms 'Aging', 'Active aging' and 'Physical activity and elderly' in the title, published from 1999 until 2018. The results were as follows: Exercise training has been extensively studied about the reduction of inflammation, oxidative stress, disease, and aging in syndrome X patients and elderly. Combined and aerobic or resistance exercise training could reduce obesity, insulin resistance, type 2 diabetes and hypertension. Exercise training has been extensively studied in cancer settings as part of prevention or treatment strategies. From this research, regular exercise has the potential to target tumor growth through regulation of inflammation and immune responses such as lactate clearance, NK cell activation (innate immunity), activation of cytotoxic immune cells, T cell activation (adaptive immunity), and immune surveillance. However, Endurance physical activity not only induces thermogenesis and diverse sports injuries but also elicits mobilization and functional enhancement of monocytes, neutrophils (which is caused by the cytokine changes such as TNF-alpha, IL-1) whereas it suppresses cell mediated immunity causing to increased susceptibility to inflammation and infections like cough and URTIs (upper respiratory track infections) in young and especially in elderly people. Therefore, Strategies to prevent physical fatigue, sports injuries include avoid overtraining, Adequate recovery and various type of rest during and after physical activity and assuring adequate nutrition supplementation such as glutamine, vitamin B, vitamin C, carbohydrate, ion or berry-contain sports beverages is helpful in physically active elderly.