Professor, Dr.Biol. J.V. Koryagina
Ph.D. E.A. Reutskaya
L.G. Roguleva
Ph.D. S.V. Nopin
Siberian Academy of Physical Culture, Omsk

Keywords: training process, biomedical support, physiology of sport, non-training techniques, ergogenic methods, rehabilitation, physical working capacity, functional systems of body, adaptation.

Introduction. Nowadays the intensity of loads in elite sport is critical. Active sports activity causes certain changes in the functional state of the body associated with adaptation to physical and psycho-emotional stress and, consequently, to the degree of tension of regulatory mechanisms. Along with the constant improvement of the educational component of the training process new, advanced technologies need to be developed to optimize sports training that help extend the range of adaptation capacities of the human body. In this connection, analysis and systemization of information on the ergogenic methods as well as the effectiveness of using them in order to restore and enhance special physical working capacity in various sports are of great interest for theory and practice of sport.

The purpose of the research was to analyze and systemize research on development and use of existing physiological ergogenic methods in sport.

The research methods included information search, gathering and analysis (papers, conference proceedings, books of abstracts, journals).

Results and discussions. Today methods that can improve performance while exercising and/or enhance adaptation to training loads are called ergogenic methods. Scientists note that ergogenic methods must meet the following requirements: - not be included in the WADA list of prohibited substances; - be physiologically and metabolically effective; - not cause undue discomfort or lead to extreme situations; - not cause immediate and deferred negative health outcome for athletes; - not cause excessive and long-term decrease of physical fitness; - not have negative reviews in publications [17].

There are different approaches to the classification of ergogenic methods used to improve physical abilities of athletes. Basically, five different classes of ergogenic methods are considered including: nutritional, physiological, psychological, pharmacological and mechanical. This paper deals with the analysis of the results of recent scientific publications on the matters of application of physiological ergogenic methods by elite athletes.

Methods of pre- (and post-) workout stimulation of physical working capacity of athletes, that accelerates the recovery processes including those during competitive activity, are of special importance [2]. Scientists of different countries are actively researching in this direction, identifying the impact of hyperoxia. A group of scientists from Canadian universities are studying the impact of hyperoxia on the content of lactate and pyruvate as well as on the partial pressure of respiratory gases in the muscles [17]. They have found that hyperoxia (60% content of O2) has an impact on reduction of muscle glycogenolysis, reduction of lactate accumulation and its utilization, reduces concentration of blood adrenaline by ~ 44% as compared with ordinary air while performing a high-intensity exercise.

J. Suchý et al., researchers from the University of Prague, tried to use inhalation of concentrated oxygen during repeated performance of the Wingate Anaerobic Test [18]. Inhalations of 99.5% oxygen when recovering after doing the Wingate Anaerobic Test significantly speed up short-term recovery processes. A much smaller decline in the performance effectiveness of the second Wingate Anaerobic Test was noted after inhaling 99.5% oxygen as compared to air. A study similar to the one described above was conducted by scientists from New Zealand [15]. They used a randomized test to assess breathing 21%, 60% and 100% oxygen during a four-minute rest after a 30-second exercise of maximum intensity during repeated exercise performance. Breathing 100% oxygen while resting after the exercise of maximum intensity improves the effectiveness of the next exercise, although fatigue indicators are also increased, and the transient ergogenic effect is thus not long – perhaps, 1-2 seconds.

As seen from the study, the use of hyperoxic gas mixture influences directly the function capabilities of the cardiorespiratory system, optimizing the autonomic support. The use of oxygen to support an athlete before a maximum load contributes to better performance of the oxygen transport system, overall performance of the heart, as well as reduction of limiting capacities of the respiratory system. Breathing hyperoxic gas mixture for 20 minutes after the exercise of maximum intensity contributes to the acceleration of the urgent restoration of the cardiovascular and respiratory systems [7].

Feedback on changes of physiological processes and performance results is one of the applications of physiological methods directly within or simultaneously with the training process. The feedback is useful in increasing performance of athletes, as well as in the course of motor learning and rehabilitation [12, 16]. However, organization and ways of feedback vary considerably. This can be attributed not only to the conditions and provision of the feedback, but also depends on the differences of the subjects. In addition, internal processes that facilitate the effectiveness of training and rehabilitation are underexplored.  

Biofeedback reaction-time training is an integral part of the psychological training of the Canadian speed skating program «Mind Room» [14]. Researchers from the universities of San Francisco (USA) and Toronto (Canada) have introduced a new system in the form of restarts. The protocol of measuring the activation of the foot pedal was set up for the feedback to be recorded when the pedal is released, not when it is pressed down, so athletes could respond simulating their actual start on the ice. The results can be reported to each athlete as feedback, and then the start signal sounds 2 seconds later for the athletes to release the pedal.

Scientists assign an important role in improving the results of athletes to the use and recording of biorhythms. V. Pougaschová with scientists from the universities of Slovakia and the Czech Republic has analyzed the relationship between biorhythms and physical working capacity of biathletes [19]. They identified 6 pm as the optimal time for the development of velocity, 9 am as the time for strength abilities, and afternoon and evening - for shooting practice.

Scientists of the University of Liverpool are conducting the most active research on sports chronobiology. They have compared responses to continuous training in the morning and in the evening in a hot environment (35 ° C) [11]. The following indicators were studied: body temperature, aerobic capacity, power output and workout time in the graded cycle ergometer test. The research was conducted at 8 am and 5 pm. The authors have detected a 9 watts increase of the average power output and a 2.8% increase of performance time in the evening compared to the morning values. 

Researchers of the Laboratory of Exercise Physiology of the University of São Paulo [9] have found that training at a late time in the day, though it leads to more stress of the cardiovascular system, is not accompanied by a decrease in aerobic capacity or perceived as more strenuous.  

According to scientists of the Department of Obstetrics and Gynecology, Division of Reproductive Endocrinology of the University of Patras (Greece) [13], elite artistic gymnasts have abolished circadian rhythm of salivary cortisol, possibly due to intense training and competitions. Artistic gymnasts have higher levels of salivary cortisol in the morning and of psychological stress compared to the level of salivary cortisol of untrained men and women.  

Currently, in chronobiological studies the focus is being shifted from studying the dynamics of body functions and physical working capacity at different times of the day to research related to allocation of rhythms of the body systems as indicators of the functional state and adaptive processes. Different researchers have shown the role of physical activity as a pacemaker synchronizing and desynchronizing human circadian rhythms.   

According to scientists of the Department of Physiology of the School of Medicine of Hokkaido University (Japan), the pacemaker of the biological clock of mammals including humans is not only bright light but also physical activity [20]. They have identified phase-shifting effects of physical exercise. Planned physical exercise during wakefulness contributed to an increase of melatonin in blood plasma. Regular exercise also contributed to a greater intensity of circadian rhythms, which is associated with the acute phase of the delayed shift of sleep/wakefulness and light/dark cycle. These results indicate that physical exercises as external time signals are useful for regulating the circadian rhythm. We had similar findings in our studies which indicate that physical activity contributes to greater rhythmicity of physiological and psychological indicators of intellectually disabled school children [3].

Scientists of the Department of Psychobiology of the Federal University of São Paulo (Brazil) and the Research Institute for Sport and Exercise Sciences of Liverpool John Moores University conducted the first study to determine the circadian rhythm at all various movement speeds and in all the muscle groups in a standardized protocol [10]. This study has shown a pronounced 24-hour rhythm in slow and fast movements of knee extensors and flexors.   

In addition, as seen from our studies of the rhythmic organization of psycho-physiological parameters of athletes of various specializations [3], the daily dynamics of psycho-physiological processes of athletes mostly has a 24-hour rhythmic structure. In addition to 24-hour rhythms those of 14 and 30 hours are detected due to the nature of sports activities: athletes engaged in cyclic dynamic sports have ultradian 14-hour rhythms, those engaged in situational sports have infradian 30-hour rhythms, and athletes engaged in strength sports can have both ultradian 14-hour rhythms and infradian 30-hour ones.  

In another work of ours [4] we have analyzed rhythmicity and defined chronobiological features of the main systems limiting physical working capacity of skiers. It has been shown that the rhythmic organization of the respiratory system of athletes is represented by ultradian 14-hour and 16-hour, nychtemeral 24-hour, infradian 30-hour rhythms. Circadian rhythmicity of the cardiovascular system of skiers is represented by nychtemeral 24-hour and ultradian 14-hour rhythms of the central hemodynamics parameters and by nychtemeral rhythms (24-hour) of the peripheral hemodynamics parameters.   

Methods of chronocorrection and optimization of the functional state of man are being developed. Scientists from the Institute of Biomedical Research VSC RAS and North Ossetian State Medical Academy offered and successfully tested new methods of state chronocorrection of athletes [8]. In their research ergogenic methods such as low-intensity magnetic-laser impact in the biofeedback mode along with intake of adaptogens ensure successful correction of pathological desynchronoses, enhance health status, overall physical working capacity and load tolerance.

We believe, transcranial electrical stimulation that uses impulse current (TES), is another promising method for immediate post-training and post-competition rehabilitation effect. This non-invasive method selectively and in strictly measured proportions activates the structures producing endogenous opiate peptides [6].

Data on the use of TES in sports practice are rare. In some studies scientists used TES for correction of psycho-physiological status of athletes. Our studies have shown that after the competition load TES usage accelerates the recovery processes of autonomic regulation of the cardiovascular system of athletes. The cumulative effect of the course of TES treatments manifested itself in the optimization of the EEG rhythms of the brain of athletes. Therefore, TES is a promising physiological method to optimize the functional state of athletes in the course of their adaptation to training and competition loads as well as in the process of recovering from them [5].

Conclusion. Thus, in the present review we have analyzed data on the findings of both domestic and foreign scientists on the use of physiological ergogenic methods that are mostly applied both for immediate and cumulative effects at the same time. The comprehensive use of physiological methods of stimulation along with engagement of training means in training cycles are strategic areas. These combinations of methods and substantiation of their use in various sports will help achieve a higher cumulative training effect, increase adaptive potential of the body of an athlete and the effectiveness of competitive activity.   

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Corresponding author: koru@yandex.ru