Effects of dance movement therapy on the rheological properties of blood in elderly women

Abstract

OBJECTIVE:

The aim of this study was to analyse the effects of dance movement therapy exercises (DMT) on the rheological properties of blood in elderly women.

METHODS:

The study encompassed group of women (mean aged: 67 years), who were subjected to three-month dance movement therapy programme (n = 20). Blood samples from all the women were examined for their haematological, rheological, and biochemical parameters both prior to the study and three months thereafter.

RESULTS:

DMT did not cause statistically significant differences in the number of erythrocytes, thrombocytes, leukocytes and the haematocrit value. DMT affected the rheological parameters of the blood in elderly women, improving the erythrocyte deformability at the lowest shear stress value and reducing the half-time of the total aggregation. Plasma viscosity and concentration of fibrinogen did not change after dance therapy.

CONCLUSIONS:

DMT modulate rheological properties of blood of older women. The results of this study suggest that physical exercise program for older women can prevent unfavorable age-related changes. Some indicators such as the haematological parameters, plasma viscosity and fibrinogen level were not affected by DMT in older women, suggesting the maintenance of homeostasis.

Keywords

Dance movement therapy elderly women erythrocyte deformability haemorheology plasma viscosity

1 Introduction

Ageing has a considerable effect on the rheological properties of human blood [1]. Blood fluidity disorders occur with age, including increased plasma viscosity and blood viscosity and the disorders of erythrocyte deformability and their increased aggregation. An increased concentration of fibrinogen in the plasma is a common phenomenon caused by a pro-inflammatory condition in elderly persons. An increased concentration of fibrinogen explains the higher plasma viscosity and higher aggregation of erythrocytes in elderly persons. Increased oxidative stress at an elderly age causes changes in the blood fluidity though decreased erythrocyte deformability, which is an important factor in deciding the blood viscosity [2]. Two distinct properties of erythrocytes contribute to blood viscosity at high and low shear rates. Erythrocyte deformability is a determinant of blood viscosity at high shear rates; while low shear viscosity is a determinant of erythrocyte aggregation [3].

Blood rheology factors are significantly affected by ageing [4], which is connected with a high incidence of chronic illnesses among elderly persons. The age-related decline in haemorheological health mainly reflects the effect of disease progression rather than the ageing process itself [5]. Increases of plasma viscosity and blood viscosity are observed in people with atherosclerosis [6] and people who have suffered a myocardial infarction [7]. Blood viscosity also increases in cerebrovascular diseases and is connected with a deterioration of cognitive functions [8]. Other studies show that the increase of blood viscosity with age does not depend on the haematocrit (Ht) and the classical risk factors for cardiovascular diseases, which suggests that ageing may have a direct effect on erythrocytes [9].

The most effective method of preventing haemorheological disorders is regular physical activity, which reduces the haematocrit, decreases erythrocyte aggregation, increases erythrocyte deformability and reduces the level of fibrinogen [10]. The current literature lacks evidence of the effects of dance movement therapy on the haematological and rheological indicators in elderly women. Therefore, the aim of this study was to analyse the effects of dance movement therapy exercises (DMT) on the rheological properties of blood in elderly women.

2 Methods

2.1 Participants

The study encompassed group of women that presented a sedentary lifestyle, who were subjected to three-month DMT programme (n = 20). The participants subjected to DMT were aged between 61 and 75 years (mean: 67.45 years). The subjects were familiarised with all the procedures and gave their informed consent to participate in the study. The protocol of the study was approved by the Local Bioethics Committee at the Regional Medical Chamber in Krakow Nr 24 /KBL/OIL/2014.

Exclusion criteria included: paralysis and paresis hindering independent mobility, severe vertigo, dementia, diabetes, cardiovascular disorders and using drugs that can modulate vascular perfusion. Blood samples from the cephalic vein (5 ml) were collected from all the women both prior to the study and three months thereafter, and were examined for the haematological, rheological and biochemical parameters. The samples were collected in vacuum tubes with K2EDTA (1.5 mg/ml).

2.2 Laboratory procedures

2.2.1 Measurements of the basic haematological parameters

The haematological parameters were measured using a blood analyser (ABX Micros 60 Haematology Analyser, Horiba ABX Diagnostics, France). The following parameters were determined: red blood cell count (RBC), haematocrit (HCT, %), mean corpuscular haemoglobin (MCH, pg), mean corpuscular volume (MCV, μm³), mean corpuscular haemoglobin concentration (MCHC, g/dl), leukocyte count (WBC, 10³/mm³), and platelet count (PLT, 10³/mm³).

2.2.2 Rheological analysis

The erythrocyte deformability and aggregation of the red blood cells was determined using a Laser-assisted Optical Rotational Cell Analyser (LORRCA, RR Mechatronics, Holland), according to the Hardeman method. The deformability was expressed using elongation index (EI) values. The EI for erythrocytes was calculated according to the formula: EI = (A– B)/(A+B), where A and B represent the vertical and horizontal axes of the ellipsoid, respectively. EI allowed for the estimation of erythrocyte elasticity and was calculated based on the change in erythrocyte shape (from round to ellipsoid) under the influence of shear stress. The following aggregation parameters were estimated: 1) aggregation index (AI, in %), 2) the amplitude and total extent of aggregation (AMP, in arbitrary units), and 3) the half time (T½, in s) which describes the kinetics of the aggregation process an disproportional to the time of reaggregation of disintegrated red cell complexes. Measurements of aggregation parameters were carried out at native haematocrit. AI was calculated from the syllectrogram (light scatter vs. time curve during a 120 s period). This method relies on the fact that there is less light backscattered from aggregating red cells.

2.2.3 Measurements of the plasma viscosity

The viscosity of the blood plasma was determined with a viscosimeter (type D-52159 Roetgen, Myrenne, Germany) with the results displayed in mPas.

2.2.4 Biochemical analyses – measurements of the fibrinogen

The concentration of fibrinogen was determined with a Chrom-7 coagulometer. The measurement was based on a determination of the changes in optic density (without simultaneous mechanical mixing) occurring during the clotting reaction, and a kinetic analysis of the reaction. The results were expressed as g/l.

2.3 Dance movement therapy programme

DMT programme lasted for 3 months (three sessions per week). In line with the motor rehabilitation guidelines for geriatric patients, each single session lasted for no longer than 45–50 minutes. The intensity of exercising corresponded to no more than 40–60% of heart rate reserve, which was calculated for each participant using the Karvonen-formula. Therefore, the heart rates of participating women during dance therapy sessions were monitored with the aid of a cardiac monitor (Polar Sport Tester, Polar Electro Oy, Finland).

DMT session started with a low-intensity warm-up lasting for 5–10 minutes and preparing the participants for more strenuous exercise. The warm-up included light exercises performed in a sitting position, such as movements of the head and distal limb segments. Due to a gradual involvement of the major joints and trunk, the patients were then forced to resume a standing position and continue exercising, marching, clapping and stamping to music. The main phase of each training session included selected steps and figures from folk dance, ballroom dance and integration dance, as well as predefined and modified choreographies, dancing-gymnastic exercises and dancing improvisation. The aim of the training was to improve the muscle strength, endurance and general exercise capacity of the participants. Moreover, practising simple choreographies improved the visual and auditory motor coordination of the patients, as well as their general physical fitness, balance and agility. The final phase of each training session lasted for 5–10 minutes and included cooling-down with breathing and relaxation exercises, as well as stretching exercises aimed at an optimisation of the training effects.

2.4 Statistics

The measurements taken prior to and after the dance movement therapy programme were subjected to a statistical analysis. The normality of distribution was verified with the Shapiro-Wilk test. Depending on variable distribution, baseline and post-therapy levels of studied parameters were compared using the Student t-test for dependent variables or the Wilcoxon signed-rank test. All calculations were carried out with the Statistica 7 package (StatSoft, USA), with the threshold of statistical significance set at p≤0.05. SS_1/2 and EI_max were calculated by fitting SS versus EI to equation, representing Lineweaver-Burke model, using a non-linear curve-fitting algorithm available in a commercial statistical package (Prism 7.0, GraphPad Software Inc., La Jolla, CA). Details have been described elsewhere [11].

3 Results

The study did not observe statistically significant differences in the red blood cell count (RBC), haematocrit value (Ht), mean corpuscular haemoglobin (MCH), mean corpuscular volume (MCV), white blood cell count (WBC) and leukocyte count (PLT) between the women after the application of the dance movement therapy programme. Only in mean corpuscular haemoglobin concentration (MCHC) a significant decrease was observed in women from the research group (Table 1).

Table 1
Mean values (±SD) or median values (with an interquartile range) of the haematological parameters in the experimental group prior to and after the dance movement therapy programme

Parameter DMT (n = 20)

Prior to DMT After DMT P

RBC (10⁶/mm³) 3.921 (±0.511) 3.856 (±0.352) p = 0.3787

Ht (%) 36.32 (±4.401) 35.33 (±2.420) p = 0.2149

MCH (pg) 31,14 (±2,013) 30,20 (±1,991) p = 0,3895

MCHC (g/dl) 33,05 (±0,488) 32,69 (±0,585) p = 0,0085^*

MCV (μm³) 85,47 (±4,599) 85,21(±4,674) p = 0,3835

WBC(10³/mm³) 5,465 (±1,171) 5,170 (±0,977) p = 0,3037

PLT (10³/mm³) 202,5 (48,5) 196,0 (44,0) p = 0,3803

Parameter	DMT (n = 20)
RBC (10⁶/mm³)	3.921 (±0.511)	3.856 (±0.352)	p = 0.3787
Ht (%)	36.32 (±4.401)	35.33 (±2.420)	p = 0.2149
MCH (pg)	31,14 (±2,013)	30,20 (±1,991)	p = 0,3895
MCHC (g/dl)	33,05 (±0,488)	32,69 (±0,585)	p = 0,0085^*
MCV (μm³)	85,47 (±4,599)	85,21(±4,674)	p = 0,3835
WBC(10³/mm³)	5,465 (±1,171)	5,170 (±0,977)	p = 0,3037
PLT (10³/mm³)	202,5 (48,5)	196,0 (44,0)	p = 0,3803

^*significantly different compared to the value determined prior to dance movement therapy (p < 0.05).

In the experimental group, a statistically significant increase of the EI at the lowest shear stress value (0.30) was noted after DMT sessions. No statistically significant changes at the other shear stress values were observed in this group (Table 2).

Table 2

Mean values (±SD) or median values (with an interquartile range) of the elongation index (EI) at various levels of shear stress in the experimental group prior to and after the dance movement therapy programme

Shear stress (Pa)	DMT (n = 20)
Shear stress (Pa)	Prior to DMT	After DMT	P
0.30	0.113 (±0.042)	0.130 (±0.045)	p = 0.0375^*
0.58	0.137 (±0.034)	0.141 (±0.029)	p = 0.5306
1.13	0.076 (0.025)	0.079 (0.023)	p = 0.9702
2.19	0.112 (0.016)	0.112 (0.010)	p = 0.3958
4.24	0.196 (±0.013)	0.197 (±0.011)	p = 0.8536
8.23	0.301 (±0.013)	0.299 (±0.012)	p = 0.4156
15.96	0.395 (±0.013)	0.393 (±0.014)	p = 0.4417
31.04	0.470 (±0.012)	0.470 (±0.014)	p = 0.9682
59.97	0.530 (±0.011)	0.531 (±0.013)	p = 0.5746

^*significantly different compared to the value determined prior to dance movement therapy (p < 0.05).

In the experimental group did not observe statistically significant differences in the SS_1/2, EI_max and SS_1/2/EI_max values after the application of the dance movement therapy programme (Table 3).

Table 3

Mean values (±SD) or median values (with an interquartile range) of the of SS_1/2, EI_max and SS_1/2/EI_max ratio in the experimental group prior to and after the dance movement therapy programme

Parameter	DMT (n = 20)
Parameter	Prior to DMT	After DMT	p
SS_1/2	7.282 (±1.195)	7.158 (±1.721)	p = 0.5755
EI_max	0.588 (±0.018)	0.584 (±0.047)	p = 0.5503
SS_1/2/EI_max	12.260 (±1.810)	12.120 (±2.818)	p = 0.6813

The DMT resulted in a marked decrease of T½, while no significant training-related changes were observed in the AI and AMP values (Table 4).

Table 4

Mean values (±SD) or median values (with an interquartile range) of the aggregation index (AI), half-time of the total aggregation (T½) and aggregation amplitude (AMP) in the experimental group prior to and after the dance movement therapy programme

Parameter	DMT (n = 20)
Parameter	Prior to DMT	After DMT	p
AI (%)	67.45 (±5.935)	69.33 (±5.891)	p = 0.0590
T½ (s)	1.807 (±0.462)	1.600 (±0.468)	p = 0.0352^*
AMP (a.u.)	16.52 (3.645)	15.56 (2.545)	p = 0.1590

^*significantly different compared to the value determined prior to dance movement therapy (p < 0.05).

After DMT, no statistically significant changes in the median of the plasma viscosity were observed (Table 5).

Table 5

Median values (with an interquartile range) of the plasma viscosity (BPV) in the experimental group prior to and after the dance movement therapy programme

Parameter	DMT (n = 20)
Parameter	Prior to DMT	After DMT	P
BPV(mPas)	1.300 (0.105)	1.290 (0.075)	P = 0.7937

No statistically significant changes in the levels of fibrinogen in the elderly women were observed in the research group (Table 6).

Table 6

Mean values (±SD) of the fibrinogen concentration in the experimental group prior to and after the dance movement therapy programme

Parameter	DMT (n = 20)
Parameter	Prior to DMT	After DMT	p
Fibrinogen	5.569 (±1.419)	5.337 (±1.188)	p = 0.4900

4 Discussion

The blood of elderly persons shows changes such as a decrease in the number of erythrocytes, and a decrease of the haemoglobin concentration and the haematocrit, which lead to anaemia. The number of erythrocytes, and consequently the aerobic capacity of the blood in elderly persons, can be increased through physical exercises [12]. Studies by Ahmadizad and El-Sayed [13] and by Hu et al. [14] also confirm that the erythrocyte count in young adult persons increases after resistance training.

In the present study, the dance movement therapy did not caused statistically significant changes in the number of erythrocytes, thrombocytes, leukocytes, haematocrit values, MCV and MCH of the research group of elderly women. Only MCHC decreased after DMT.

A research study by Bobeuf et al. [15] that examined the haematological parameters after six months of resistance training in a group of elderly women and men (61–73 years of age) also did not observe statistically significant changes in erythrocyte, thrombocyte and leukocyte counts, haemoglobin content, MCV, MCH, MCHC and the haematocrit. Ageing may weaken the response to resistance training, which may be related to body homeostasis, which in turn is responsible for maintaining the physiological proportions in the blood [15, 16].

The deformability of erythrocytes depends on the elasticity of cell membranes, shape of the red blood cells, morphology of the vascular bed, and intraerythrocytic viscosity of the haemoglobin, and it decreases with age [17]. The correct deformability of erythrocytes in the bloodstream has a crucial role in vascular blood flow and is responsible for the effective supply of oxygen to working muscles [18]. Studies examining the effect of long term exercise on red blood cell deformability have produced conflicting results. In some studies a substantial decrease was reported, while in the others no change or even an increase was found [19].

In the present study, DMT caused an increase of erythrocyte deformability at the lowest shear stress value. In a study by Marchewka et al. [20], the erythrocyte deformability in elderly women at the lowest shear stress values (0.30 and 0.58) also improved after a five-month dance programme.

The increase in red blood cell deformability may be associated with a decrease in mean corpuscular haemoglobin concentration (MCHC) after DMT application. There is negative relationship between red blood cell flexibility and MCHC, thus indicating that the lower the MCHC, the greater the flexibility of red cells. Red blood cell deformability depends on the internal haemoglobin concentration. Physical activity dilutes the blood, increases the ease of flow and increases oxygen supply to the working musles [19].

According to Manetta et al. [21], regular cycling training maintains a low haematocrit level in cyclists aged 51.6 years, but it does not prevent an increased rigidity of erythrocytes or their aggregation.

Simmonds et al. [22] researched the rheological properties of blood in elderly women aged between 56 and 74 years who suffered from Type 2 diabetes, following a 12-week training programme that involved walking on a treadmill. The research revealed a decrease of erythrocyte aggregation and deformability in the studied women.

An increase of red blood cell aggregation connected with age is caused by an increase of the fibrinogen concentration in the plasma. Similarly, a decrease of the fibrinogen concentration after physical training causes a decrease of the aggregation of red blood cells, which has been confirmed by some studies [2].

In the present study, DMT caused a reduction of the half-time of the total aggregation. However, as far as the other erythrocyte aggregation parameters are concerned, DMT did not caused statistically significant changes.

A single training session usually leads to increased plasma viscosity and blood viscosity, and decreased erythrocyte deformability [23]. On the other hand, regular physical training is one of the most effective methods of preventing haemorheological disorders [2].

Physical effort is followed by a phenomenon called haemoconcentration, which is caused by an increase of plasma concentration due to a loss of water, and this in turn leads to an increase in the number of red blood cells, haemoglobin and haematocrit [15]. This phenomenon takes place due to at least five separate mechanisms: the redistribution of erythrocytes in the vascular bed; an increase of red blood cells though their release from the spleen, which contracts during physical effort; enrichments of the plasma with proteins that likely infiltrate from the lymphatic system; loss of water through sweat caused by thermoregulation; and the transfer of water into the muscle cells [24].

Previously, it was believed that increased blood viscosity had a negative influence on the cardiovascular system and the aerobic capacity. However, most recent studies suggest that dynamic changes in the blood viscosity may have a positive effect on the functioning of blood vessels during exercise, through the production of nitric oxide [2].

Twenty-four hours after the physical effort, the effect of excessive viscosity reverses. The volume of the plasma increases, which indicates a considerable dilution of the blood, and positive rheological changes in the red blood cells take place [25]. This process is referred to as ‘auto-haemodilution’, which is a positive adaptive change – it increases endurance and resistance to tiredness during long-term effort by increasing the stroke volume, improving the effectiveness of thermoregulation mechanisms, improving the rheological properties of the blood, etc. Consequently, blood viscosity decreases and blood fluidity improves, which increases the blood flow to muscles and improves the oxygen supply to working tissues [26].

Increased blood viscosity can be explained by an increase of plasma viscosity [9], especially in women [2]. Plasma viscosity and blood viscosity decrease after regular exercise, as a consequence of a decrease of the fibrinogen concentration in the plasma [2].

In the present study, DMT did not cause a statistically significant change in the plasma viscosity.

Plasma viscosity depends on the level of fibrinogen, which increases with age and normally achieves the upper limit in elderly persons; while the levels of other plasma proteins change only minimally [27]. Training reduces the level of fibrinogen, and the difference in the plasma viscosity between training and non-training persons is mainly attributed to a lower concentration of fibrinogen in the training persons [10]. Para et al. [28] believe that, in persons between 65 and 78 of age, regular physical activity, even of a moderate intensity, correlates with a lower level of fibrinogen regardless of the person’s sex, which then reduces the risk of cardiovascular complications or even death.

Stratton et al. [29] revealed that six months of regular physical training will improve aerobic capacity and considerably reduce the level of fibrinogen in the plasma of elderly men (by 13%).

Conversely, the study by Marchewka et al. [20] did not reveal statistically significant changes in the level of fibrinogen in a research group of elderly women after a 5-month programme of dance movement therapy.

In the present study, DMT did not cause statistically significant changes in the levels of fibrinogen in the research group of elderly women. Nonetheless, considering the increase in the level of fibrinogen with age, maintaining the homeostasis of this parameter is a positive phenomenon.

5 Conclusions

DMT affects the rheological parameters of the blood of elderly women, improving the erythrocyte deformability at the lowest shear stress values and reducing the half-time of the total aggregation. Some indicators such as the number of erythrocytes, thrombocytes, leukocytes and the haematocrit value, plasma viscosity and fibrinogen level are not affected by DMT in older women, suggesting the maintenance of homeostasis. This observation is particularly favorable in the context of natural age-related tendency to increase in those parameters. Those findings advocate implementation of dance therapy programs in older women.

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