OF MORPHOLOGICAL CHARACTERISTICS AND MAXIMAL OXYGEN CONSUMPTION OF FOURTH GRADE PUPILS BASED ON GENDER

On a sample of 71 respondents, 37 boys and 34 girls, age of fourth grade elementary school, accordingly 9 years +/6 months, it is assessed correlation and prediction of maximal oxygen consumption based measures of morphological range. Maximum oxygen consumption was measured by indirect method, using a fi eld test of maximal multiple load of feedback running at 20 meters. Range of morphology was analyzed based on 5 measures of longitudinal dimensionality, 4 measures of volume and body mass and 3 measures of transversal dimensionality. Results of correlation analysis showed that in both sexes there was no statistically signifi cant correlation between results of maximal oxygen consumption and measures of longitudinal dimensionality, while regression analysis confi rmed that there was no statistically signifi cant prediction of maximum oxygen consumption based on measures of longitudinal dimensionality. While the correlation analysis deduced that part of volume measures and body mass and transversal dimensionality have statistically signifi cant correlation only with female respondents with results of maximal oxygen consumption. Regression analysis showed statistically signifi cant prediction of maximal oxygen consumption based on part of volume measures and body mass and transversal dimensionality. It is determined that female respondents with larger volumes of the thigh and lower leg, accordingly with smaller diameters of knee joint and ankle joint most likely will achieve better results in applied test, and therefore higher maximal oxygen consumption.


INTRODUCTION
One of the maximum capabilities of the organism to transport and use oxygen is the amount of oxygen consumed in some physical work (Živanić, Životić-Vanović, Mijić, & Dragojević, 1999).Other authors state that the maximum oxygen consumption is defi ned as level of oxygen consumption per minute at which further increases the work load does not lead to a further increase in oxygen consumption.Maxi-mal oxygen consumption (VО 2max ) is defi ned, too, as maximum amount of oxygen that a body can consume during intense physical activity, in a time of one minute (Šentija, 2010).On the quantity of maximum oxygen consumption could be aff ected by various factors, such as aerobic capacity, age and gender.Aerobic capacity is quite genetically determined.In practice, it is recognized that the ratio is approximately 2:1, meaning that the level of aerobic capacity can be increased at the most for a one third if appropriate training is applied.Gender also determines the level of aerobic capacity, and diff erences are evidential in early childhood.Th erefore six-year boys have higher values of maximum oxygen consumption than girls (Mitić, Ropret, Višnjić, & Radisavljević, 1997).Th e value of maximal oxygen consumption increases with growth and development and achieves the maximum in a period of 18 to 25 years old.Maximal oxygen consumption is expressed in absolute (l/min, ml/ min) and relative measures (ml/kg/min).Realistic results are provided by relative measures, so those were used in this study as well (Živanić et al. 1999).As part of battery of Eurofi t tests for assessing physical working capacity of children aged 5 to 19 years, in the countries of the European Union, as a test for the assessment of endurance it is used the test of maximal multiple load of feedback running at 20 meters, by authors Leger & Lambert 1982.Th is test represents one of optimal tests to estimate durability.Its practicality is refl ected in the fact that it can be implemented in a small space and on a relatively large sample of respondents at the same time.Th e greatest value of this test is that it eliminates wrong assessment of tempo selection and running speed at respondents, as the tempo of its performance is dictated and gradually increases.Range of morphology was analyzed with longitudinal, transversal dimensionalities and with range of volume and body mass.Several authors dealt with the defi nition of morphological characteristics.Under the morphological characteristics of the anthropological status of the man most oft en it is considered a certain system of basic anthropometric latent dimensions (Malacko, 1991).Also, morphological characteristics of anthropological state of man are usually implied processes of growth and human ontogenetic development (Malacko, & Rađo, 2004).Based on previous researches, four main the most often identifi ed factors are: a longitudinal dimensionality of the skeleton, transversal dimensionality of the skeleton, the mass and volume of the body and subcutaneous adipose tissue (Malacko, 1991).In a study of Mikić, Biberović, & Mačković (2001) are pointing out that height of the body during the period of junior school age up to 8 years keeps previous growth tempo, while aft er 9 years old growth tempo slows down considerably.For bone growth in width transversal dimensionality of the skeleton factor is responsible.Th e factor which is oft en called factor of circular dimensionality of the body, and which is responsible for the total mass and volumes of body, presents the factor of mass and volume of the body.It showed that it has the highest correlation with motor skills and is considered to be one of the most important factors in morphological range (Malacko, 1991).Body mass is associated with the impact of other factors that affect physical development in general, but the most is dictated by nutrition itself.Systematic physical exercise in children with an average body mass, with the optimal nutrition, leads to an easy weight gain, where this increase goes for multiplication of active tissues, especially muscle.According to Herlok, older preschoolers are featuring stepwise increase in muscle mass and that increase is 75% of muscle weight, according to (Stanković, 2007).Information about the structure of morphological characteristics is very important in terms of their transformation.Morphological characteristics are infl uenced by genetic and environmental factors.Th e infl uence of genetic factors is not the same for all latent morphological dimensions.Innateness coeffi cient for dimensionality of skeleton is approximately 0.98, 0.90 volume of the body, a fat tissue 0.50 (Malacko, 1991).Th erefore, the greatest transformation under the infl uence of exogenous factors is possible for adipose fat tissue, then body volume, and it is almost negligible with dimensionality of the skeleton (Malacko, 1991).With regard to treated problem of this scientifi c paper, the aim is analysis of relations between morphological characteristics and maximal oxygen consumption of fourth grade pupils in primary school in relation to gender.Th e research problem of this study regarded to relations of morphological characteristics and maximal oxygen consumption of fourth grade primary school pupils in relation to gender.In relation to the aim and research problem, there were set and analyzed certain assumptions, which ware related to whether the morphological measures have a correlation and prediction for value of maximal oxygen consumption.

METHOD Th e sample of respondents
Th e study was conducted on a sample of 71 children of age fourth grade primary school, respectively 9 years +/-6 months, on 37 male and 34 female re-assess general and specifi c working capacity.For endurance estimates in a larger number of respondents, the practice has shown that it is the best to use selected fi eld test.Th is test was used in this study according to the protocol of test that gave Leger and Lambert (Leger & Lambert, 1982).Th e test is performed so that the respondents are running between two lines at a distance of 20 meters to the pace dictated by the signal.At each beep the subject must be with both feet on over the line.Th e aim of the test is that the respondents run off as many as possible shares.Th e initial velocity is 8.5 km/h (20 m by 9 seconds) and corresponding light running aft er a certain time tempo increases to 0.5 km/h.Th e test is terminated when subject is no longer able to follow the default tempo, or when three times in a row does not arrive at the line at the beep.Audible signal announces any change in speed (level).Each level contains a certain number of shares.Monitoring of running shares is made on the sheet with the specifi ed levels and the number of shares in each level.Before starting the test were explained to respondents bearing in mind their age.Assessing the relative maximal oxygen uptake was performed using the calculator estimate that was used on the offi cial web site.
Th e reason that applied this test to measure endurance, is that the results of this test in previous research showed a high level of correlation when are compared with the results obtained using laboratory test: r=0.76 (Leger & Lambert, 1982), r=0.68 for boys, r=0.69 for girls, and r=0.76 for both genders combined (Van Mechelen, Hlobil, & Kemper, 1986), r=0.87 (Boreham, Paliczka, & Nicholos, 1990), r=0.93 (Naughton, Colley, Kemey, & Smith, 1996) and r=0.83 for boys and r=0.76 for girls (Machoney, 1992), which indicates on objectivity of test for maximum load of multiple feedback run on 20 meters as the real indicator of aerobic capacity .

Processing data
Applied descriptive statistics were calculated using the arithmetic mean, variation width, standard deviation, variance, measures skewness asymmetry and kurtosis, Kolmogorov-Smirnov test.Applied is also a correlation analysis that examined the association between achieved results and regression analysis to determine the qualitative correlation, or prediction criteria of the predictor.Th e process used statistical program SPSS (version 11.0).spondents.Respondents were involved in some form of physical activity, in various schools of sport.Th e pupils participated in this study voluntarily and had full consent of parents and teachers of physical education.Th e predictor variables were evaluated maximum consumption of oxygen: a test for the assessment of maximal oxygen consumption (20-MOC), tested run distance (RUNDISTA), running speed in the test (RUNNSPE).(Leger & Lambert, 1982).

Th e sample of variables
Techniques and conditions of measurement of morphological characteristics were conducted in accordance with the International Biological Program (IBP).Measurement of anthropometric characteristics was carried out in a sports hall in the aft ernoon.Respondents were in the sporting goods.Th ere are used the standard anthropometric instruments, calibrated before each measurement.Before measurement, anthropometric levels and points were determined and marked precisely.For realization of this program are used the following instruments: anthropometer by Martin, sliding caliper and a metal measuring tape.Maximum oxygen consumption was measured by indirect method, using a fi eld test of the maximum of multiple loads in feedback running at 20 meters.Th e tests used for the evaluation of durability, like the basic motor skills, are almost always be an integral part of the group of tests which is used to

RESULTS
Table 1 shows the descriptive statistics and results of longitudinal, transversal dimensionality, volume and body mass of both genders.Th e values of KS test of normality appropriate layout of the results.Th e average time to test (20-MOC) in male respondents was 207.22 seconds, or 3:27:22 minutes, according to the tables corresponding to the approximate oxygen consumption VO 2max of 27.35 ml/kg/min.Th e female respondents had an average time of 170.60 seconds, or 2:50:60 minutes, according to the same plates approximately corresponds to the current consumption of oxygen from the VO 2max 25.10 ml/kg/min.In this way it is proved by many studies that have dealt with maximal oxygen uptake in children depending on the sex of the respondents.To the conclusion is that male respondents aged seven years have higher maximal oxygen consumption VO 2max then female respondents (Mitić, et al., 1997).Gender determines the level of aerobic fi tness and diff erences are apparent in early childhood.
Th ose six-year boys have higher values of maximum oxygen consumption than girls (Živanić, et al., 1999).Research of Robinson, Astrand, Rodhala, Davies and Anderson showed that boys aged ten years a considerable advantage over the girls in this age of maximum oxygen consumption VO 2max (according to Bijelić, & Simović, 2005).Maximum pulmonary ventilation in minutes in a boy 9 years old is increased by 10 liters compared to girls of the same age (Mikić, & Bjeković, 2001).Also, the results of the tests which evaluated the average distance covered (RUNDISTA) and average running speed (RUNNSPE) that the respondents made when conducting this test is determined based on the table.In all these tests, the average scores were in favor of the male respondents compared to female respondents, and based on this we can conclude that they have achieved better results.Analyzing the numerical relationship between the results of longitudinal dimensionality of the skeleton and the results of tests for the assessment of maximal oxygen uptake, in a tested run distance and running speed in the test, it was found that there was no statistically signifi cant correlation with all measures in both genders.However, although this study did not show that the longitudinal dimension aff ect the results of tests for the assessment of maximal oxygen uptake, some previous studies have reached certain results related to this issue.Th e infl uence of the anthropometric characteristics of the conditional parameters is investigated at football players (Wong, Chamari, Dellal, & Wislőff , 2009).Th e authors have shown that there is a statistically signifi cant correlation between body height and the results of the test 20-MOC (r=0.26) and body height and VO 2max (r=0.35).When is analyzed numerical correlation between measures of volume and mass of the body, and the results of tests for the assessment of maximal oxygen uptake, in a tested run distance and running speed in the test, is showed a statistically signifi cant correlation between morphological measures the volume of the thigh (VOLULOWLE) with test scores (20-MOC), (RUNDISTA) and (RUNNSPE), and measure the volume of the lower leg (VOLUBREA) with test scores (20-MOC), (RUNDISTA) in female respondents.Measures transversal dimensionality of the skeleton diameter of the knee joint (DIAMKNEEJO) and the diameter of the hock (DIAMHOCK) in female subjects showed a statistically signifi cant correlation with the test results (20-MOC).At male respondents has not been established any numerical correlation.
Table 4 shows the inter-correlation between the results of the test for the assessment of maximal oxygen consumption (20-MOC) results in the lengths of run distance test (RUNDISTA) and running speed in the test (RUNNSPE).Observed a high level of correlation coeffi cients suggests or allows the assumption of high levels of concordance of results of regression analysis of predictors of criteria in the current space.
In Tables 5, 6 and 7 the results of the regression analysis that examined the qualitative correlation between the criterion and predictor variables and based on that determined the prediction criteria of the predictors.the lower extremities are refl ected in initiating, supporting and dynamic balance.Th e importance of strengthening the muscles of the lower extremities is most prevalent in the stiff ness of the connection between the pelvis and trunk.Th is rigid connection is important in determining the effi ciency of pressure which passes through the leg at the moment of contact with the ground.Th is pressure can be transferred to various parts of the pelvis-trunk system, which should be avoided because it may lead to unnecessary wastage of potential energy in parts of the body where it is not needed.When training for muscle development must take into account the use of muscle to hind leg moved forward and to fi x it in the position of running.By analyzing the biomechanics of an open kinetic chain of the lower extremity, it was evident that, as the lower leg to the long arm of gravity higher, which causes greater force fl exor muscles of the knee joint.Th is leads to a greater speed of movement of the lower leg, and hence a greater speed, so many times how many times faster leg is greater than the gravity force arm muscle, and the number of times greater than the force of the muscle force of gravity.Here are concludes that as the force fl exor muscles of the lower leg (quadriceps femoris) is greater, will be higher and the speed of movement of the lower leg (Mikić, & Bjeković, 2004).If more force fl exor muscles (quadriceps femoris) of lower leg, it can be assumed that the greater the volume of the thigh, which justifi es the results obtained in this study.A more detailed analysis can be assumed that respondents with larger volume of the thigh and lower leg can achieve better results in tests of maximal oxygen uptake, tested run distance and running speed in the test.Th is statement can be confi rmed based on the results in Table 6.which shows that if the volume of the thigh increased by 1 centimeter in female respondents, can be expected to run greater distances to 22.26 m and increase the running speed of 0.18 m/s resulting in an increase in maximal oxygen uptake of 0.53 ml/min/kg.While, if the volume of the lower leg increases by 1 centimeter, can be expected to run a greater distance to 32.06 m, which will also result in an increase in maximal oxygen consumption of 0.63 ml/min/kg.Confi rmation of this hypothesis regression analysis is associated with the obtained inter-correlation results shown in Table 4. On the basis of analysis of the results, the assumption of the object and the problem of work, which is expected statistically signifi cant correlation and pre-

DISCUSSION
Th e results in Table 5 showed that there is no signifi cant qualitative correlation between predictor and criterion variables, resulting in the inability to predict the results of maximal oxygen consumption based on the measurement of longitudinal dimensionality of the skeleton.On the basis of analysis of the results, the assumption of the object and the problem of work, which is expected statistically signifi cant correlation and prediction of maximal oxygen consumption based on the measurement of longitudinal dimensionality of the skeleton, are not fully accepted.
In Table 6 the results of the regression analysis that examined the qualitative correlation between the predictor variables and measures of volume and body mass.Th e results show that all measures of volume and mass of the body, on the basis of measures the volume of the thigh and lower leg circumference, possible to predict the results of maximal oxygen uptake.Analyzing the impact of scale on the upper leg maximal oxygen uptake, in a tested run distance and running speed in the test, and also impact the volume of the lower leg to the maximum oxygen consumption and run so the distance to the test in female respondents, it was noted that there is a statistically signifi cant impact of these morphological characteristics.Th e impact of morphological characteristics on the results of maximum oxygen consumption, running distance and running speed in the test can be associated with the embodiment of this test.Description performing this test mentioned above and it can be assumed that for its successful execution, in addition to a good stamina, which plays a major role in maximal oxygen consumption, and the need to own a good running speed, coordination and rhythm of movement.What is the maximum oxygen consumption, which is estimated by this test is directly related to the length of the tested run distance and running speed in the test, so it can be assumed that respondents with higher volumes of lower extremities can achieve greater distance and running speed, and therefore the higher maximum oxygen consumption.Th e impact of large-scale upper leg and lower leg in running speed was analyzed by Tončev (2000) and he concluded that it is necessary to develop the muscles of the lower extremities, which have three basic functions while running.Th e functions of the muscles of diction of maximal oxygen consumption based on the measurement volume and weight of the body is partially accepted.Th e reason for the partial acceptance is that it is only a measure of volume and body weight showed a statistically signifi cant association, or just based on some measures can make a statistically signifi cant prediction of maximal oxygen uptake.
Criterion variable diameter of the knee joint and ankle joint showed a statistically signifi cant prediction of maximal oxygen uptake (Table 7).Based on the results of the correlation relationship that has a negative sign can be assumed that the respondents in the smaller diameters of the knee joint and ankle joint can run so achieve greater distance and greater running speed in the test.With the realization of greater distance and running speed, will achieve better results in the test (20-MOC), and therefore a higher maximum oxygen consumption.Th e impact of the measures on the transversal dimensionality of the skeleton running speed was involved in a lot of authors, among them Molnar and Smajić (2008).Correlations they concluded that most of the statistically signifi cant relationship with the specifi c motor skills have morphological variable diameter hock (DIAMHOCK) and the diameter of the knee joint (DIAMKNEEJO).Th ese two transversal measures of the skeleton are the only statistically signifi cant in the correlation with specifi c motor skills where the focus is on running speed.In addition to increased speed, which aff ects the better results in the test (20-MOC), it can be assumed that the respondents express greater coordination also can achieve better results on this test.Correlation measures the transversal dimensionality of the coordination analyzed (Jakovljević, Bijelić, Jovanović, Božić, & Vukić, 2013).Th ey came to the conclusion that the diameter of the hock (DIAMHOCK) and the diameter of the knee joint (DIAMKNEEJO) signifi cantly aff ect the expression of coordination.Th e signifi cance of coordination is refl ected in the performance test (20-MOC), which was applied in this study.Coordination aff ects the proper running technique, then the technique of change of direction, which is typical for this test, and rational use of energy throughout the course of the test.It is in any case important for the rational use of energy will allow for greater run so distant, and therefore higher maximum oxygen consumption.Detailed review of the results of the regression analysis, it can be assumed that respondents with lower diameter of the knee joint and ankle joint to achieve better results in tests of maximal oxygen uptake.Th is statement can be confi rmed based on the results in Table 7 showing that if the diameter of the knee joint and ankle joint "reduce" to 1 centimeter in female subjects, will achieve a higher oxygen consumption for 0.37 or 0.88 ml/min/kg.In addition, confi rmation of this assumption of regression analysis is associated with the results of inter-correlations shown in Table 4. On the basis of analysis of the results, the assumption of the object and the problem of work, which is expected statistically signifi cant correlation and prediction of maximal oxygen consumption based on the measurement of the transversal dimensionality of the skeleton, are partially accepted.Th e reason for the partial acceptance is that it is only part of measures transverse dimensions of skeleton showed a statistically signifi cant association, or just based on some measures can make a statistically signifi cant prediction of maximal oxygen uptake.

CONCLUSION
Based on the analysis of relations of morphological characteristics of respondents and maximal oxygen consumption in relation to gender, it has been explained in few next conclusions.Measures of longitudinal dimensionality of skeleton in subjects of both genders showed no statistically signifi cant correlation with the results of the test for the assessment of maximal oxygen consumption, tested run distance and running speed in the test.Morphological characteristics of volume and body mass showed positive relations with the results of the test for the assessment of maximal oxygen uptake in a test run, so distance and running speed in the test only in female respondents.A more detailed analysis of the qualitative relationship, or prediction, it can be concluded that respondents with larger volume of the thigh and lower leg can achieve better results in tests of maximal oxygen uptake, running distance in the test and running speed in the test.A positive relation was observed in the transverse correlation of morphological features with the test results to estimate maximal oxygen uptake and was found statistically signifi cant prediction, based on which it can be assumed that female respondents with smaller diameters of the knee joint and Th e variables in this study were divided on the criterion and predictor: Criterion variables were evaluated morphological status of respondents in relation to gender: a) Th e gender of respondents, b) Longitudinal dimension: body height (BH), leg length (LEGLEN), the length of the upper leg (LENUPPLE), the length of the lower leg (LENLOWLEG), foot length (FOOTLENG), c) Th e volume and mass of the body: body weight (BW), the volume of the upper leg (VOLUPPLE), the volume of the lower leg (VOLULOWLE), the volume of the breast (VOLUBREA), d) Transversal dimension: diameter of the knee joint (DIAMKNEEJO), diameter of the hock (DIAMHOCK), the width of the foot (WIDTFOOT), (Metikoš, Prot, Hofman, Pintar, & Oreb 1989).

Table 1 .
Descriptive statistics results of longitudinal, transversal dimensionality, volume and body mass of both genders

Table 2
shows the descriptive statistics of test results to estimate maximal oxygen uptake (20-MOC).

Table 2 .
Descriptive statistics of test results 20-MOC, RUNDISTA and RUNNSPE Chart 1.Average values of results relative oxygen consumption (ml/kg/min) both genders Chart 2. Average values of results test speed run (m/s) in both genders

Table 3 .
Correlation between the longitudinal skeleton dimensionality, volume and mass of the body and transversal dimensionality of the skeleton, with the results of tests 20-MOC, RUNDISTA and RUNNSPE

Table 5 .
Predicting the results of tests 20-MOC, RUNDISTA and RUNNSPE based on measures of longitudinal dimensionality of the skeleton

Table 6 .
Predicting the results of tests 20-MOC, RUNDISTA and RUNNSPE based on measures of volume and body mass

Table 7 .
Predicting the results of tests 20-MOC, RUNDISTA and RUNNSPE based measures transversal dimensionality of the skeleton