The influence of physical exercises on the body of women aged 25-30 years old within KhMAR-Ugra

Фотографии: 

M.N. Mal’kov, associate professor, Ph.D.
S.I. Loginov, professor, Dr.Biol.
A.S. Kintyukhin, postgraduate
M.V. Batraeva, postgraduate
D.A. Khodosova, postgraduate
Surgut state university KhMAR-Ugra, Surgut

Key words: body mass index, cardiorespiratory system, physical exercises, physical load, physical health, women aged 25-30 years.

Introduction. It is known that the living conditions in KhMAR-Ugra (Ugra) are unfavourable due to the effects that the ecological factors and the peculiarities of the geographical location of the city of Ugra have on the human health and organism [5]. Scientists of Ugra have been putting attempts into practice for long as to the improvement of the state of human health, in particular by affecting with targeted physical exercises the organism of people living in Ugra [8]. Lately, such physical exercises are more frequently held in gyms and not outdoors. This touches not only upon children of every age, but adults with cardiovascular and respiratory diseases too. The air temperature in Ugra stands firm at 30ºC and below for many months [5, 7, 6], thus the so-called "gym" form of physical exercises is getting most preferable for Ugra citizens. However, there are several issues in this case as well. Physical exercises, organized by commercial fitness centres, are available to a limited extent, even for people with an average income. Apart from that, the surveillance of the health state of people who are regularly engaged in physical exercises is inadequate or totally non-existent. In such a case, the result of suchlike classes in a long-term perspective is unclear and ambiguous. There arises the necessity to organize targeted recreational activities combined with biomedical support to people engaged. However, a solution can be found, for example, with the help of specially organized (and available for people with different incomes) physical exercises, conducted on the basis of budgetary institutions of the city of Ugra.

The purpose of the study was to examine the influence of regular classes of recreational physical culture on the characteristics of physical fitness and health of 50-year-old females, permanent residents of the KhMAR-Ugra.

Materials and methods. The study involved 20 women randomly selected from the staff of Surgut State University. All the study participants were divided into the experimental group "EG" (n = 10, age of 28.7 ± 5.64 years) with control activity in the form of 36 week long specialized recreational training sessions; and the comparison group "CG" (n = 10, age of 28.7 ± 3.56 years), working independently occasionally. Before the beginning of the study, researchers measured the women's body length with no shoes on (BL) using a stable stadiometer with approximation of 0.5 cm; body mass (BM) using medical scales with approximation of 0.1 kg; expiratory chest circumference at expiration (CC exhalation, cm), at inhalation (CC inhalation, cm) and pausing (CC pause, cm); waist circumference (WC, cm) and hip circumference (HC, cm); along with breathing diagnostics for the indicators of the cardiorespiratory system in the physiological rest position and after a standardized test "sit-to-stand" for 3 seconds. They kept record of the indicators of heart rate (HR, bpm) at rest, after exercise and during recovery; the value of systolic (SBP, mm Hg) and diastolic (DBP, mm Hg) blood pressure in the physiological rest position; the value of vital capacity (VC, ml) and timed inspiratory capacity (Stange's test, sec); power in right and left hand muscles (kg). They evaluated the following indices: body mass index (kg/m2), power index (%), birth-death ratio (ml/kg), endurance index (r.u.). As to the levels of physical fitness, physical health, personal and situational anxiety and health self-assessment, they were evaluated using a set of tests of the expert system "CosMos" [2, 3]. The control activity (independent variable) was a combination of recreational training sessions, in which aerobic (walking and jogging on a Bremshey treadmill) and power (body-weight exercises with the use of specialized strength training equipment) physical exercises were used. The exercises mentioned above were combined with breathing and stretching ones. The sessions were conducted on a three-times-per-week basis for 40-60 minutes and the repeated diagnosis was made in 12, 24 and 36 weeks. Descriptive statistics and regression analysis were carried out using the Statistica 6 Software, assessing the significance of the differences derived by the criteria of the Student's t-test and the Wilcoxon test at the significance level of p≤0,05.

Results and discussion. The comparison of the anthropometric/functional indicators in the EG of women aged 25-30 years and the CG did not reveal statistically essential differences before the study (Table 1). It is noted that, the BM and the body mass index (BMI) of women regularly engaged in recreational training sessions with the use of aerobic (walking and jogging on a treadmill) and power (body-weight exercises using specialized strength training equipment) physical exercises decreased significantly throughout 36 weeks of classes. At the same time, the BM and BMI of women engaged on a case-to-case basis (CG), in contrast, increased significantly after 24 weeks and kept increasing over the next 12 weeks of the observation. The women of the EG, after 36 weeks of regular training, looked visually more "fit" than before the study. This fact is also confirmed by the reduced hip circumference.

On the contrary, women of the CG had an increase in hip, waist and chest circumferences while exhaling. The calculated on the basis of the initial data, power index in women of the EG increased throughout 36 weeks, while in the comparison group similar changes were not detected (Table 1).

Table 1. Dynamics of anthropometric indicators of women during 36-week training sessions, Me (± 95% CI)

Indicators

Experimental group, n=10

Control group, n=10

Before

After

12 weeks

After

24 weeks

After

36 weeks

Before

After

12 weeks

After

24 weeks

After

36 weeks

 

 

 

 

 

 

 

 

Age,

years

28.0

(24.7; 32.7)

28.0

(25.1; 33.1)

29.0

(25.4;

33.4)

29.0

(25.7;

33.7)

29.5

(26.1; 31.2)

29.5

(26.6;

(31.4)

30.0

(26.9; 32.1)

30.5

(27.1; 32.2)

Body

length, cm

162.0

(160.1; 166.3)

162.5

(160.0; 166.2)

162.5

(160.0; 166.0)

163.0

(159.8; 166.0)

165.0

(161.4; 171.2)

165.0

(161.6;

171.2)

165.0

(161.8; 171.4)

165.0

(161.7; 171.3)

Body

mass, kg

59.0

(55.5; 68.3)

57.0

(53.8; 67.6)

* 2.1

57.5

(53.8; 67.0)

* 3.1; 3.7

56.0

(52.7;

66.3)

* 4.1; 4.8

69.0

(58.0; 76.4)

69.0

(58.5;

77.2)

69.0

(59.8; 79.1)

* 7.5; 7.6

71.0

(60.8; 80.6)

* 8.5; 8.7

BMI

kg/m2

22.6 (21.0; 25.5)

22.0

(20.4; 25.2)

* 2.1

21.8

(20.4; 25.1)

* 3.1

21.4

(20.0; 24.9)

* 4.1; 4.3

23.8

(21.6; 26.8)

24.4

(21.8;

27.0)

24.7

(22.2; 27.6)

* 7.5; 7.6

25.5

(22.6; 28.2)

* 8.5; 8.7

CC

exhalation, cm

88.0

(83.9; 92.3)

87.0

(82.8; 92.0)

86.5

(82.5; 91.7)

86.0

(82.0; 91.2)

89.5

(84.6; 95.0)

89.5

(85.5;

96.5)

* 6.5

90.5

(85.7; 97.1)

* 7.5

91.5

(86.5; 97.7)

* 8.5; 8.7

CC

inhalation, cm

95.0

(90.1; 98.7)

94.0

(88.9; 97.5)

93.5

(89.1; 97.0)

94.0

(89.4; 97.4)

96.0

(90.2; 101.6)

96.0

(90.0;

101.6)

95.0

(90.2; 101.7)

95.5

(90.2; 102.2)

CC

pause, cm

90.5

(86.0; 94.8)

88.0

(85.0; 93.8)

88.0

(84.6; 93.5)

88.0

(84.5; 93.5)

91.0

(86.6; 97.8)

91.0

(86.7;

98.4)

92.0

(87.4; 98.8)

92.5

(87.5; 98.9)

Waist

circumference, cm

75.5 (70.5; 82.3)

75.0

(69.8; 82.2)

75.0

(69.4; 81.7)

75.0

(69.1; 81.5)

78.0

(72.4; 85.2)

78.0

(72.2;

85.6)

79.0

(73.0; 86.6)

* 7.5; 7.6

80.0

(73.6; 87.4)

* 8.5; 8.7

Hip

circumference, cm

96.5 (93.2; 104.4)

95.0

(92.3; 104.1)

95.5

(92.2; 104.0)

95.0

(91.5; 103.5)

* 4.3

101.5

(95.4; 107.4)

102.0

(96.1;

107.3)

103.5

(97.3; 107.9)

7.6

104.5

(97.7; 108.1)

Power

index, %

31.6 (29.8; 36.8)

35.4

(33.5; 41.7)

* 2.1

38.9

(35.4; 44.1)

* 3.1

42.7

(38.7; 47.5)

* 4.1

36.6

(31.3; 42.7)

36.6

(30.9;

43.3)

38.7

(31.6; 42.4)

35.3

(30.6; 39.0)


Legend: Me - median, CI - confidence interval, CC - chest circumference (cm), BMI - body mass index, kg/m2. * – the differences between indicators in the corresponding columns are significant (p<0.05)

Based on the analysis of physiological indicators, a significant increase was established in VC in women of the EG, throughout 36 weeks of regular performance of physical exercises. On the other hand, in the comparison group, the decrease of those indicators became evident after 24 weeks in women of the same age (table 2).

Table 2. Dynamics of physiometric indicators of women aged 25-30 years throughout 36-week training sessions, Me (± 95% CI)

Indicators

Experimental group, n=10

Control group, n=10

Before

After

12 weeks

After

24 weeks

After

36 weeks

Before

After

12 weeks

After

24 weeks

After

36 weeks

 

 

 

 

 

 

 

 

VC, ml

3,170

2,834; 3,666)

3,195

(2,840; 3,669)

3,270

(3,008; 3,732)

3,560

(3,291; 3,897)

* 4.1; 4.3

3,785

(3,193; 4,019)

3,805

(3,253; 3,997)

3,595

(3,170; 3,872)

* 7.6

3,495

(3,121; 3,741)

* 8.7

HR, bpm

Rest

75.0

(72.2; 81.2)

72.5

(66.5; 76.6)

72.5

(67.1; 78.1)

71.0

(65.9; 74.5)

* 4.8

70.0

(66.3; 78.3)

75.0

(70.4; 81.6)

76.5

(73.4; 82.4)

79.0

(75.9; 85.3)

* 8.5

Exercise

136.0

(129.6; 145.4)

128.0

(124.8; 139.0)

* 2.6

135.0

(126.9; 139.9)

* 3.7

133.5

(128.0; 139.0)

* 4.8

139.0

(128.9; 147.1)

147.0

(134.3; 151.9)

145.0

(140.5; 150.9)

* 7.5

148.0

(142.1; 151.6)

* 8.5

Recovery

102.5

(94.3; 113.9)

95.0

(86.5; 105.1)

* 2.1

91.0

(83.8; 104.4)

* 3.1

93.0

(84.0; 98.4)

* 4.1; 4.8

98.5

(89.4; 108.0)

100.0

(93.3; 109.7)

100.0

(97.4; 108.4)

102.5

(100.2; 109.6)

BP, mm Hg

Systolic

121.0

(113.3; 129.8)

120.5

(113.0; 125.4)

121.0

(115.9; 126.6)

118.5

(116.7; 122.5)

* 4.8

118.0

(108.5; 121.1)

122.0

(115.7; 126.5)

* 6.5

125.5

(120.5; 127.5)

* 7.5

125.0

(122.7; 126.7)

* 8.5

Diastolic

75.5

(70.8; 79.6)

78.5

(71.2; 82.4)

79.0

(70.5; 81.5)

74.5

(71.0; 78.0)

* 4.8

72.5

(65.2; 78.4)

79.5

(71.4; 83.2)

* 6.5

78.0

(74.5; 80.7)

81.5

(78.1; 83.5)

* 8.5; 8.7

Stange's test, sec.

45.0

(30.2; 50.4)

60.0

(39.1; 64.5)

* 2.1

56.0

(42.1; 62.3)

* 3.1

60.0

(53.7; 64.3)

* 4.1;

4.3; 4.8

47.5

(34.0; 58.4)

47.0

(35.3; 75.7)

* 6.5

50.0

(33.7; 70.3)

37.5

(27.8; 57.2)

* 8.7

Life index, ml/kg

52.4

(46.9; 58.6)

52.4

(48.5; 59.2)

56.1

(50.6; 61.8)

61.8

(55.4; 66.7)

* 4.1;

4.3; 4.8

54.7

(47.7; 61.4)

53.2

(47.9; 60.9)

49.8

(44.8; 58.7)

* 7.6

48.6

(43.3; 56.0)

* 8.5; 8.7

Endurance index, r.u.

11.6

(9.7;

13.9)

9.8

(8.0; 11.9)

* 2.1

10.1

(8.1; 11.9)

* 3.7

9.5

(8.0; 11.0)

* 4.1; 4.8

10.9

(8.8; 13.0)

11.8

(9.9; 14.2)

12.1

(11.3; 14.0)

* 7.5

13.4 (12.1; 14.4)

* 8.5; 8.7


Legend: Me - median, CI - confidence interval * – the differences between indicators in the corresponding columns are significant (p<0.05)

At the same time, the HR dynamics in the physiological rest position in women of the EG tended to decrease throughout 36 weeks of activity, although statistically significant differences were not detected. In women of the CG, the HR dynamics had an increasing tendency, as after 36 weeks they were significantly higher, compared with the HR values of the entrance diagnostics. With the carrying-out of the standardized "sit-to-stand" test for 3 min., after 36 weeks of training, the HR in women of the EG was insignificantly lower in comparison with the entrance testing. The women of the CG, as a result of repeated testing procedures, after 24 and 36 weeks had significantly higher values, compared with the HR values recorded after the entrance testing. Upon comparing the EG with the CG on the basis of the results of the "sit-to-stand" test, it was observed that immediately after the exercise, the women of the EG, after 12, 24, 36 weeks of activity, were found with significantly lower HR indicators, which means that it was easier for them to perform the exercise and their efficiency was higher. At the same time, according to the HR indicators, the recovery was significantly faster, i.e. women of the EG recovered better, after carrying-out the "sit-to-stand" test after 12, 24, 36 weeks of training. Upon comparing the EG with the CG, it was observed that, after 36 weeks, the HR in women of the EG was significantly lower than in women of the CG (Table 2). The blood pressure of women of the EG was reduced after 36 weeks, still it is not statistically significant. At the same time, in the case of young women of the CG, a significant increase in the blood pressure was observed after 36 weeks. The values of blood pressure of women of the EG were essentially lower than those in the CG after 36 weeks. According to the results of the Stange's test, it was found that women of the EG, after 36 weeks of targeted activity, showed a significantly longer timed inspiratory capacity than those in the CG, which as a fact implies the higher efficiency of the respiratory system. In addition, statistically significant changes in the birth-death ratio were indicated in the EG, as well as higher values of the very index in comparison with the CG. Based on the endurance index, we can come to the conclusion that women of the EG had significantly higher indicators than those of the CG (Table 2). At the same time, the dynamics of the endurance index in women of the EG is positive, while the changes after 36 weeks as to the group are average.

Moreover, women of the EG, in comparison with those of the CG, were found with lower values ​​of situational and personal anxiety, and on the average these values conformed to the moderate anxiety level, which as a fact indicates psycho-emotional stability (Table 3). At the same time, women of the CG had high anxiety levels after 12 weeks and later on (24 and 36 weeks).

Table 3. Dynamics of situational and personal anxiety of women, Me (±95% CI)

Indicators

Experimental group, n=10

Control group, n=10

Before

After 12 weeks

After 24 weeks

After 36 weeks

Before

After 12 weeks

After 24 weeks

After 36 weeks

 

 

 

 

 

 

 

 

Situational

anxiety, r.u.

37.0

(29.7;

40.5)

36.5

(30.6; 47.2)

* 2.6

34.5

(30.6; 45.6)

* 3.7

41.0

(34.5; 51.7)

36.5

(32.0; 43.0)

51.0

(48.3;

54.5)

* 6.5

55.0

(51.2; 58.0)

* 7.5

50.5

(45.0; 53.8)

* 8.5

Personal

anxiety, r.u.

43.0

(37.9;

493)

45.0

(38.9; 48.9)

* 2.6

41.0

(33.0; 46.8)

* 3.7

42.5

(38.1; 47.5)

* 4.8

46.0

(42.1; 49.7)

50.0

(47.2;

55.4)

* 6.5

55.5

(50.1; 57.6)

* 7.5

52.5

(44.2; 56.0)


Legend: * p – the differences between indicators in the corresponding columns are significant (p<0.05)

Proceeding from the data shown in Fig. 1, women of the EG estimated the state of their own health ("health self-assessment" survey) as above the average. On the other hand, women of the CG assessed their own health as average.

Fig. 1. Change in the health self-assessment of women in the dynamics of a 36-week training process. Health self-assessment is presented in r.u. - 1 = low; 2 = below the average; 3 = average; 4 = above the average; and 5 = high level. The vertical lines correspond to confidence interval of 0.95%

The conducted studies showed that, according to the data used by our expert system, the level of physical fitness of women of both the experimental and the comparison group varied from low to below the average after 36 weeks of training (Fig. 2, A).

In addition, it was observed that the health level of women of the EG and CG was below the average by the end of the 36-week period of physical-culture and recreational activity (Fig. 2, B).

Fig. 2. Change in the physical fitness level – PFL (A) and physical health - PHL (B) of women in the dynamics of a 36-week training process in the experimental and control groups. PHL and PFL are presented in points - 1 = low; 2 = below average; 3 = average; 4 = above average; and 5 = high level. The vertical lines correspond to confidence interval of 0.95%

According to the results of the regression analysis, the correlation between the value of blood pressure of women at rest and their age came to light (n=20). SBP and DBP have an increasing tendency with age (Fig. 3, A), which, as a fact, is consistent with the literature data having been acquired earlier [11]. The correlation is described by the regression equations: SBP = 138.6 - 1.91x + 0.0408х2 and DBP = 75.2 - 0.44х + 0.0131х2. Under the influence of regular training sessions, the blood pressure value in women of the EG decreased, but not significantly (Table 3).

The correlation between the women’s hip circumference value and age was also evidenced (n=20): it tends to increase with age (Fig. 3, B). The correlation is described by the regression equations: hip circumference = 52.75 + 2.73x - 0.0369х2. Regular training sessions contribute to the decrease of the hip circumference value in women of the EG (Table 1).

Fig. 3. Correlation of the values of blood pressure (A) and hip circumference (B) of women aged 25-30 years with their age

Conclusion. Proceeding from numerous studies, regular physical exercises contribute to the reduction of the BM and its index, as well as to the normalization of the value of blood pressure [1, 4, 10]. Within the framework of our study, regarding the comparison of the BMI - resulting from the entrance testing - of the women of the EG with the standard indicators, it's possible to determine the normal body mass as 22.6 (21.0; 25.5) kg/m2 (18-25 kg/m2 as standard), although two young women of the group had excess body mass. By the end of 36 weeks of training, all study participants had reduced their BMI to the standard level of 21.4 (20.0; 24.9) kg/m2. At the same time, the BMI - resulting from the entrance testing - in women of the CG was 23.8 kg/m2 (21.6; 26.8) and reached the value of 25.5 kg/m2 (22.6; 28.2) after 36 weeks. Since BMI characterizes the risk level of cardiovascular diseases' occurrence, its increase in women of the CG should be considered as a negative phenomenon. What's more, the reduction of the hips' circumferential size in women of the EG is considered to be a beneficial prognostic sign. Apart from the alteration of the indicators presented above, an increase regarding the power index of the women of the EG was observed. Thus, prior to exposures and after 36 weeks, this index's value was 31.6 (29.8; 36.8) and 42.7 (38.7; 47.5) %, and corresponded to the below-average indicator (51-55% is the average value for the power index), according to which further directional activity is required.

We observed beneficial, in our opinion, changes in functioning of the cardiorespiratory system in the women of the EG after 36 weeks of activity, expressed by the evidenced increase of  indicators such as HR, blood pressure, timed inspiratory capacity, vital capacity, as well as life and endurance indices. So, for example, after 36 weeks of training, HR in the physiological rest position was decreased from 75.0 (72.2; 81.2) to 71.0 (65.9; 74.5) bpm and corresponded to the standard values (60-90 bpm). All the while, the women of the EG, in the dynamics of this period, demonstrated an increase of the HR indicator, both after the standardized physical load and during the recovery period. The improvement of the state of the cardiorespiratory system is also ascertained by the indices, including birth-death ratio, amounting to 52.4 ml/kg (46.9; 58.6) prior to the beginning of the activity, and corresponded to a lower-than-standard level (55-60 ml/kg is the standard level for women) and 61.8 (55.4; 66.7) ml/kg after 36 weeks, which is already the standard value. The alteration of this indicator's value states the improvement of the functionalities of the external respiration apparatus in women of the EG. In addition, we observed a value change of the endurance index from 11.6 (97; 13.9) prior to the activity to 9.5 (8.0; 11.0) r.u after 36 weeks, i.e the decrease of this index, in this case, shows the change of the level from below the average to average (after 36 weeks) and, consequently, the improvement in functioning of the cardiovascular system. Moreover, studies of local authors also indicate the beneficial effect physical exercises have on the state of the cardiovascular system of women. For example, in one of those studies, in which 26 women aged 30-50 years participated, aerobic exercises were used in the form of recreational jogging and walking, breathing exercises and combined developing exercises with walk-in music. According to the study's results, the author noticed an improvement in the state of the participants' cardiovascular system [9].

The psycho-emotional state of women of the EG was stable after 36 weeks, which is certified by the presence of moderate situational and personal anxiety of this group's representatives.

Regarding physical fitness level, women, who regularly performed physical exercises, undoubtedly, had a better physical fitness level, which in turn ascertains the importance of the regular pursuit towards physical exercises. However, the development of the women's health state is a difficult and time-consuming process; that's why we didn't find any statistically significant differences between health states of women of the EG and the CG after 36 weeks of activity, except that a developmental tendency as to the health state can certainly be traced (including the correspondence of the health self-assessment of its objective level). In our opinion, a further engagement of the study's participants with the recreational physical culture is required. This conjecture is confirmed by the results we have obtained through the regression analysis. It has been found that the values of blood pressure and hip circumference in women increase with age, which can increase the risk of the occurrence of cardiovascular diseases.

Hence, regular physical exercises done within the controlled classes promote decrease of the body mass index, waist and hip circumference, enhance external respiratory function, reduce diastolic blood pressure and heart rate after load in 50-year-old women, permanent residents of the KhMAR-Ugra (Surgut).

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