Professor, PhD T.V. Popova¹
PhD, doctoral student Y.I. Koryukalov¹
PhD, Associate professor O.G. Kourova¹
Dr.Biol. I.P. Dovbiy^1
1South Ural State University, Chelyabinsk

Keywords: university students, athletes, fatigue, mental stress, adaptation.

Introduction. It is a well-known fact that fatigue affects adaptation to various activities, including university studies. Overall health issues commonly found in university students indicate that adaptation to academic load remains a relevant problem. Combining studies and sports means heavier loads on the body, which may trigger maladaptive symptoms. On the other hand, some scientific research suggests that young people who are into sciences, sports, and arts keep fit throughout the whole period of academic studies and achieve more occupational success as graduates [3, 7].

The findings of the research [5, 6] suggest that the fitness shape and good health of students depend on the level of fatigue caused by academic activities. Mental stress is another key factor in getting out of fitness shape. Exam-related stress and strain are the underlying causes of worsening of both physical and psychic states of students. Intensified academic activities also contribute to deteriorated psychofunctional states of students. While the mechanisms of adaptation to academic load in students who combine studies and sports still require more profound research, the findings of the research in question are essential for optimisation of an academic process.

Objective of this research was to characterize fatigue and mental stress in students who combine sports and university studies.

Structure and methods of research. 62 students aged between 17 and 21 volunteered to take part in the research. The subjects formed four groups, groups 1 and 2 being made up of students who did not do any sport, the total of 32 students, 17 females and 15 males, while groups 3 and 4 were made up of first-class athletes and Candidate Masters of Sport of various specializations and skill levels, the total of 30 students, 15 females and 15 males, their athletic experience ranging from 3 to 5 years. Static handgrip strength measurements were taken to assess fatigue in the subjects during their academic activities. The subjects had their static grip strength measured by squeezing hand-held dynamometer with the grip strength of 1/3 of the maximum until the onset of fatigue (that is, until they made a verbal statement they were unable to continue to hold down the dynamometer at the set value). The value of 1/3 of the maximum that we provided in the course of the measurements was the mean value for any age group [1]. The static grip strength was assessed based on how long a subject was able to squeeze the dynamometer and measured in seconds. Each subject had his/her blood pressure, heart rate, and cardiointervalography measurements taken before, during, and after the exercise sitting on a chair. Heart rate variability was calculated according to the Baevsky's mental stress evaluation procedure [2]. In addition, we assessed neuro- mental stress using the T.A. Nemchin's method [10].

Table 1. Static grip strength (с) in students at various stages of academic process (М±м)

Note: * means confirmed differences from the semester period data; ** means confirmed differences between sporty and unfit subjects; at р<0.05

The results of this research suggest that fitness shape of the students varied from stage to stage of an academic period. Sporty students had higher static handgrip strength indices throughout the semester than the unfit students, the indices being the lowest among the unfit females and the highest among sporty males (Table 1).

A significant decrease in the static grip strength indices could be observed in the subjects, especially the sporty ones. The measurements of static grip strength suggested that students became fatigued towards the end of every academic year, when end-of-semester exams took place, especially towards the end of the fifth year, just before graduation exams.

The very nature of adaptive heart reactions to local static loads also varied from group to group. Heart rate and blood pressure indices measured in the unfit female and male 1st year students while at rest were practically no different from those in the sporty students (Table 2). Diastolic blood pressure values were significantly higher at rest in the unfit females than in the sporty ones.

In end-of-semester exam period, heart rate and systolic blood pressure were found to be higher than throughout the semester on average in all of the 1st year subjects. Significant changes in heart rate were found in the unfit females and in systolic blood pressure in all the males. Diastolic blood pressure indices were somewhat higher in all the subjects (and significantly higher in the sporty males) and lower in the unfit females during the exams than throughout the semester period. Significant increase in heart rate and blood pressure was found in all the subjects when subject to local muscle work, with the increase rates being higher in the unfit subjects than in the sporty ones.

Table 2. Heart rate and blood pressure indices in 1st year students subject to local muscle work in the semester period (М±м)

Note: * are significant differences from the initial values; ** are significant differences between sporty and unfit subjects; at р<0.05.

Increased heart rates were found in all the subjects during the exams and the 1^st and 2^nd years of studies, the increase being lower in the sporty males. Systolic and diastolic blood pressure indices increased during the exams, especially in the unfit students, with the reaction close to hypertensive in the unfit males. The highest diastolic blood pressure indices were also found in the unfit males.

All in all, the heart performance data collected while at rest and during local static work tests suggested that  functional heart strain increased in the students as they did their 1^st and 2^nd year studies, with the strain being more pronounced in the unfit students than in the sporty ones.

The differences in the structure in heart rate variability between the sporty and unfit 1^st year students were the most pronounced in the females. The unfit subjects had higher (р<0.05) mode amplitude (АМо = 33.30±1.03%) and tension index (TI)(TI = 82.44±3.05 conventional units) versus sporty ones who had 29.8±1.07 and 75.17±4.05 respectively. The unfit males had the highest АМо indices, 36.14±2.01%. More significant increase in the АМо indices under loads was observed in the sporty males rather than the unfit females. Most of the subjects had a pronounced increase of the tension index (р<0.05). The unfit males had the highest TI indices caused by loads, 156.27±9.11 conventional units.

Before the exams, 70% of the sporty subjects were under mild mental stress (30-50 range) while the rest 30% (51 to 70 grades) were under moderate mental stress. After the exams, mental stress indices remained within the moderate range (51-70) in 10% of the subjects, while 90% of the subjects had average tension values.

At the beginning of the research, 40% of the subjects had moderate mental stress values (51 to 70 grades), while 60% had mild mental stress values. After the exams, 30% of the subjects had moderate mental stress values and 70% had mild mental stress values.

We found that mild mental stress predominated among the sporty subjects, while there were fewer moderate mental stress cases than among the unfit ones. Adaptive changes that developed in the sporty students throughout the semester were those of increasing fatigue and emotional tension, but their levels were lower than those in the unfit students.

We established criteria for adaptation to academic load, which characterize levels of fatigue and emotional tension in students, namely  1) “satisfactory” – heart rate increased by 10 bpm, blood pressure increased by 10 mmHg, TI increased by 20 conventional units, and static grip strength being 50 to 70 sec; 2) “strained” – heart rate increased by 20 bpm, blood pressure increased by 20 mmHg, TI increased by 30 conventional units, and static grip strength being 30 to 45 sec; 3) “overstrained” – heart rate increased by 25 or more bpm, blood pressure increased by 30 or more mmHg, TI increased by 40 or more conventional units, and static grip strength being less than 25 sec.

Results and discussion. Our earlier research into functional states of central nervous system [11] also suggested that three static grip strength female groups aged 17 and 18 were detected; higher strength meant higher resistance to fatigue, longer pre-fatigue time, and enhanced functional reserves of the central nervous systems.

Another work of ours suggested that an occupational psychophysiology course involving scientific-based organisation of intellectual work, as well as regular relaxation sessions of university students majoring in social works caused healthy changes in their psychophysical body states.  Following implementation of the course, we found that students had decreased fatigue and improved psycho-emotional state. The results of this research suggested that recreational and preventive activities were a must for university students who combine sports and studies.

Disharmonic physiological performance parameters caused strain, overstrain, or even maladaptation, depending on the advancement degree of the disharmony. The research [12] found out that 59% did their studies under chronic mental stress, while 27% formed a risk group [12]. 

The researchers [8] found out that exam-related stresses affected the state of circulatory and respiratory systems in students aged between 17 and 19, and highlighted that 1^st year students developed hypertension before and after exams, while 2^nd year students had hypotension after exams. The researchers attributed their findings to long-term adaptive processes that occur in students.

The research [13] suggested that stress-resistant individuals had higher heart rate and TI values when they worked under emotional stress, as well as more pronounced increase in heart rate and TI values, compared to the rates under normal conditions. The researchers [9, 15] viewed the degree of functional lability and strength of nervous processes that determine informational and adaptive reserves of the human nervous system as the leading psychophysiological adaptation parameters.

Methods to reduce fatigue and enhance working capacity through, e.g., relaxation session, will contribute to students’ good health, given that their fitness shape and health depend on the level of fatigue they had during their studies [14].

Conclusions

1. The sporty students had less pronounced changes in cardiovascular system parameters during exams and higher fatigue threshold in terms of static grip strength than in the unfit students.
2. Cardiovascular systems of the sporty students tended to overreact to local physical work, namely, they had blood pressure increased by 10 to 20 mmHg, TI increase by 40 to 60 conventional units, and mode amplitudes АМо – by 10 to 15% due to improved capability to mobilize body reserve through elevated tension of central regulatory mechanisms.
3. Health-promotion technologies must be embedded in the academic curriculum to prevent excessive fatigue in students with adaptive levels 2 and 3, which are “strain” and “overstrain” respectively.

References

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Corresponding author: tati.popova2010@yandex.ru

Abstract

The paper studies psychophysiological functions of university students that major in management and combine studies and sports. 62 students aged between 17 and 21 volunteered to take part in the research. The subjects formed four groups, groups 1 and 2 being made up of students who did not do any sport, the total of 32 students, 17 females and 15 males, while groups 3 and 4 were made up of I degree athletes and Candidate Masters of Sport of various specializations and skill levels, the total of 30 students, 15 females and 15 males, their athletic experience ranging from 3 to 5 years. Static hand fatigue measurements were taken to assess fatigue in the subjects during their academic activities. Analyzed were static grip strength, blood pressure, and heart rate variability according to Baevsky's procedure in the students both while at rest and during local muscle work tests, and assessed their neuropsychic strain. It has been proved that adaptive changes in both sporty and unfit students involve onset of fatigue and emotional strain, their levels being considerably lower in the sporty students than in the unfit ones. We have also established criteria for description of fatigue and neurophysic strain levels in students.