Physical condition of female students with different level of body mass deficiency

Purpose: to study the features of morphofunctional and motor characteristics of female students with body mass deficiency and with normal body mass. Material: it was examined 17-21-year-old female students (n=1937). All students were in the main medical group according to the health condition and attended classes on discipline Physical culture. It was carried out the anthropometrical and physiometric examination of female students. Results: It was determined the low integrated criterion of physical fitness of female students with body mass deficiency. It was defined the dependence between the decrease in level of physical fitness and decrease in body mass of female students. It was determined reliable differences between the morphofunctional parameters and results of motor tests of female students with different body mass. Conclusions: The obtained data allow to correct educational process on physical training of students using integrative pedagogical methods and methods of training.


Introduction
The body mass of the person is the integrated criterion of levels of metabolic, energy, hormonal, and other processes in a human body [1,2] and now it is considered by many researchers as one of the key parameters of physical development of the person [3,4].
Recent researches devoted to the physical development of the students witness about the increase in a number of students with body mass deficiency or excess body mass. The number of students of full-time study with a deviation of body mass reaches 30-40% [5]. There are a few scientific works devoted to problems of students' body mass deficiency in comparison with works concerning problems of excess body mass [6].
More than 30% students of Volga Technical Institute have problems with body mass: increase and decrease of the norm. 17,7% females and 12,5% males of this institute have a body mass deficiency [7]. According to the authors, it indicates the serious disorder of constructive metabolism processes in the young organism. About 18% students of Moscow Universities have a body mass deficiency. Then females have the body mass deficiency in twice more often than males [8]. Among students of Yaroslavl Medical University, females have body mass deficiency more often than males (25% and 17% respectively) [9]. It is defined that the number of students with body mass deficiency doubles from 15,5% in 18 years up to 30,6% in 23 years [10]. There is a research proved that 63,5% female students of Far Eastern Federal University with body mass deficiency have decrease in working capacity [11].
The considerable deviation of body mass from norm influences on physical and mental activities, the somatic health of the person. Also, it affects negatively on professional activity [8], reproductive system of females [12,13], complicates pregnancy and childbirth [14,15]. The modern process of students' studying becomes more computerized [16] and inactive [17,18]. It is determined the decrease in the motivation of students to physical culture training [19]. A lot of researchers consider the following reasons of students' body mass deviation from the norm: hypodynamia [20,21], a disorder of nutritional status [22], hormonal changes in the organism [23], the influence of psychogenic factors [24]. The increase of intellectual and psychoemotional loads, noncompliance with a base of a healthy lifestyle by students [2,30], interest in computer games and Internet influence negatively on physical [25,26], mental [27] and somatic [28,29] health of the youth.
The body mass of the person responds to the volume, intensity, and regularity of physical culture and sports training [31,32]. The component structure of a body is the level and harmony of person's physical development. The component structure of a body is the criterion of health condition and physical activity of the person [33,34].
It is determined that the physical fitness and physical development of students with body mass deficiency are closely connected with a muscular component of body structure on the basis of the analysis of correlation interrelations [35]. Therefore, such students demonstrate low results in tests of hands' muscle strength [36,37] and the general endurance [35] at physical culture training. There are data that students with body mass deficiency have hands' muscles strength decrease almost twice [11]. It is determined the dependence between the content of muscle mass in the component structure of female students' body and the number of classes on discipline "Physical culture" [38].
Studying of questions concerning level's interrelation of students' physical development with physical activity, the comparative analysis of morphofunctional characteristics and physical fitness of female students with different body mass is relevant.
Hypothesis. Authors presuppose that the received results of a research can be used during creation of individual and motivated motor programs for correction of the physical condition of female students with body mass deficiency.
The purpose of the work is to study features of the morphofunctional and motor characteristics of the organism of female students' with body mass deficiency in comparison with physical conditions of females with normal body mass.

Material and methods.
Participants. it was examined female students of junior courses (n=1937, 17-21-year-old) of Irkutsk National Research Technical University. All students were in the main medical group according to the health condition and attended classes on discipline Physical culture. 2 times a week. The performed work doesn't prejudice the rights and doesn't endanger the wellbeing of female students according to ethical standards [39].
Organization of a research. The anthropometrical and physiometric examination of female students was conducted using standard techniques [40]. The females were divided into three groups: with the normal body mass "N"; with body mass deficiency "D"; excess body mass "E". The sample of examined females was divided into 5 sigma classes (gradations) according to the body mass parameter value: М±0,67 σ -is "average" value of body mass parameter for sample. If the value of parameter was within the range from М±0,67 σ to М±1,34 σ, the body mass value was estimated as "above average" or "below average". If the value of an parameter was beyond of М±1,34 σ, the gradation was estimated as "high" or "low".
The motor qualities of female students were measured using the range of tests. It was used the following tests: 20 m run (sec); 10x5 m shuttle run (sec); 5 min run (m); hung (sec); sit-up (times); trunk flexion (cm); standing long jump, trunk flexion (cm) [47,48].
Statistical analysis. It was used programs "Microsoft Excel", "StatSoft Statistica 6.1" and the author's complex "Analysis of Physical Health Data of Population" (state registration of the program ECM №2010612275, from 3/26/2010). It was defined the arithmetic average value of parameters (M), mean square deviation (σ) and standard error (SE). The reliability of distinctions of average values of independent samples was estimated by parametrical methods by means of Student t-test. Statistically significant were considered differences between values of parameters at level р<0,05.
It was determined the decrease of BMI parameter value by 14,9% in females of group "D" in comparison with females of the group "N". Females of groups "N" have better somatometrics and physiometrics parameters, than all females with body mass deficiency (р<0,05). Females of groups "D" with gradation "below average" have lower value of parameters of flexibility and trunk muscle strength tests (tab. 2). In this group muscle strength of shoulder girdle were higher, than in females of groups "N" (р<0,05).
Females of group "D" with gradation "low" of body mass have the lowest parameters in four of seven physical fitness tests (shuttle run, 20 m run, 5 min run, sit-up). Strength parameter in the test "hung" was higher, than in females of groups "N".
Results of research of body structure component ( fig. 1) shown the difference of quantitative content of muscular (MM) and fatty (FM) mass between females with body mass deficiency and female students with normal body mass (р<0,05).
In body component structure of females of group "D" Note: * -reliable differences between parameters of "N" and "D" groups (Р<0,05) # -reliable differences of parameters in group "D" (Р<0,05) Note: * -reliable differences between parameters of "N" and "D" groups (Р<0,05) # -reliable differences of parameters in group "D" (Р<0,05) with gradation of body mass "below average" content of muscular (in 9,3%) and fatty (in 12,3%) mass is less, than in females of group "N" with gradation "average". Females of groups "D" with gradation of body mass "low" have less content of muscular (in 14,8%) and fatty (in 27,2%) mass in body component structure, than in female students of group "N" with norm body mass.

Discussion
Body mass characterizes level of metabolic, energy, plastic and other processes in a human body [1,49]. According to the WHO classification, the body mass index parameter value <18,5 kg/m 2 is considered as chronic energy insufficiency or body mass deficiency [46]. Study of the body mass deficiency distribution among youth, especially females as future mothers, is relevant [12,50]. According to our data, approximately 27,15% of females students of Baikal Technical University have body mass deficiency. This parameter is within the sigma deviation from M = -0,67 σ to M = -1,34 σ and below that will comport with results of other researchers in various regions of Russia [9,10].
The analysis of our results showed the difference between somatometric and physiometric parameters of females with normal body mass and body mass deficiency. Females of groups "N" have better somatometric parameters (length and body mass, CC) and physiometric parameters (VLC, dynamometry of hands' muscle strength, HBR at rest and HBR recovery time after 20 squats, Robinson's Index), than all females of groups "D" (р<0,05). Among females of group "D" higher results of somatometric and physiometric parameters have females with gradation "below average", than females with gradation "low" (р<0,05; except the characteristic of HBR after 20 squats in 30 sec). Results of our researches are confirmed by scientific works concerning the interrelation between body mass deficiency, a disharmony of physical development and low physical working capacity among students of Far Eastern Federal University [11] and Ural Federal District of Russia [51].
According our data all females with body mass deficiency have reliable low parameter of cardiovascular system condition (HBR at rest and HBR recovery time after 20 squats), than females with normal body mass (р<0,05). It will comport with results of research of cardiorespiratory system in students of Volga Institute [36].
According to some authors [11] one of the reasons of low physical efficiency of females with body mass deficiency is the insufficient efficiency of cardiovascular system. Decrease in overall performance of cardiovascular system of an organism of females of group "D" is confirmed by increase in 13,9% of Robinson Index parameter value in comparison with value of this parameter in females of group "N" (81,6±0,52 and 70,2±0,22 c.u. respectively), р<0,05. Our data will comport with researches concerning the definition of Robinson Index in women of the first mature age with normal body mass index [52].
According to our data, the physical fitness of females with body mass deficiency is much lower in comparison with test results of students with normal body mass. It is confirmed by researches of other authors [7,11]. We have found dependence between decrease in level of physical fitness and decrease of female students' body mass. Females of group "D" with gradation of body mass "below average" have lower values of motor tests parameters (situp, trunk flexion), than females of group "N". Females of group "D" with gradation of body mass "low" have rather lower parameters in tests of physical fitness (shuttle run, 20 m run, 5 min run, sit-up), than females of group "N" (р<0,05).
The mean score of integral criterion of physical fitness ( fig. 2) of females of group "D" with gradation of mass "below average" and "low" is 2,97±0,01 and 2,68±0,23 points respectively. It is lower in 13,4% and in 21,8% of mean score of students with a normal body mass (р<0,05). We presuppose that low characteristics of physical condition of females with body mass deficiency are caused by weak work of myocardium and small content of muscular tissue in body structure. It will comport with the results of other researchers [31,38]. The insufficient content of muscular component in females of group "D" leads to decrease in results in motor tests of strength, high-speed and general endurance. These results were lower, than in students with a normal body mass. The muscle mass deficiency doesn't significantly influence on working capacity in the static mode of shoulder girdle muscles [7]. It explains rather high values of parameters in all females with body mass deficiency in the test "hung", in comparison with parameters of students with a normal body mass.
Teachers of physical culture at the universities are recommended to use the individual differentiated approach to the choice of aerobic physical exercises of average intensity for the females with body mass deficiency. It should be used the exercises on the basis of sports and game technologies for the development of speed, strength and dexterity. It adapts the females' cardiovascular system to physical activities. It also will increase high-speed and general endurance of female students. The further comprehensive study of questions concerning physical fitness of females with body mass deficiency will increase in efficiency of physical training.

Conclusions
1. 17-21 year-old females with body mass deficiency have rather lower somatometric and functional characteristics of organism (the content of muscle and fatty mass, motor qualities), than in females with a normal body mass (р<0,05). It is determined the less body mass of females, the lower is the level of their physical fitness.
2. The obtained data concerning features and interrelations of the morphofunctional characteristics and motor qualities of females with different body mass allow to correct educational process on physical training with use of integrative pedagogical methods and methods of training.

Conflict of interests
The author declares that there is no conflict of interests.