Effects of dance therapy on the selected hematological and rheological indicators in older women

Abstract

OBJECTIVE: The aim of this study was to analyze the effects of dance therapy on selected hematological and rheological indicators in older women.

METHODS: The study included 30 women (aged 71.8±7.4), and the control group comprised of 10 women of corresponding age. Women from the experimental group were subjected to a five-month dance therapy program (three 45-minute sessions per week); women from the control group were not involved in any regular physical activity. Blood samples from all the women were examined for hematological, rheological, and biochemical parameters prior to the study and five months thereafter.

RESULTS: The dance therapy program was reflected by a significant improvement of erythrocyte count and hematocrit. Furthermore, the dance therapy resulted in a significant increase in the plasma viscosity, while no significant changes in glucose and fibrinogen levels were noted.

CONCLUSIONS: Dance therapy modulates selected hematological parameters of older women; it leads to increase in erythrocyte count and hematocrit level. Dance therapy is reflected by higher plasma viscosity. Concentrations of fibrinogen and glucose are not affected by the dance therapy in older women, suggesting maintenance of homeostasis. Those findings advocate implementation of dance therapy programs in older women.

Keywords

Ageing dance therapy hematology hemorheology plasma viscosity

1 Introduction

Ageing represents natural and unavoidable period in everyone’s life. The global fraction of people living to senility increases successively, and demographic ageing of societies is one of the symbols of 21st century. Ageing is not solely a statistical phenomenon; it has also serious social and economic consequences. Among others, this problem should be also analyzed in the context of growing therapeutic requirements, demand for rehabilitation and care, and questions related to geriatric ergonomics.

Dance therapy is attractive and relatively less exhausting therapeutic modality for older patients. According to literature, rhythmic exercise is one of the most comprehensive forms of therapy; since it modulates both the biology and the psychological and social needs of humans [1].

Physical activity in the form of rhythmic exercise to music (dance therapy) prolongs the period of physical fitness and independence of older people, improving the function of circulation and respiratory systems, as well as muscular elasticity [2]. Furthermore, it plays a role in the prevention of various disorders, including obesity, diabetes, osteoporosis, ischemic heart disease, and arterial hypertension [3].

Ageing is associated with growing concentrations of plasma fibrinogen, leading to higher viscosity of the plasma and whole blood, and enhanced aggregation of erythrocytes [4]. An age-related increase in fibrinogen concentration was reported by Kovacs et al. [5]. In their study, average plasma fibrinogen concentration of individuals between 60 and 74 years of age amounted to 3.3 g/l, compared to 3.5 g/l, in 75- to 90-year-old subjects, and 4.0 g/l in participants older than 90 years of age. Elevated level of fibrinogen constitutes a principal determinant of plasma viscosity [5, 6]. Fibrinogen is a natural macromolecule that forms bonds between erythrocytes, which enable their aggregation. This latter process is postulated the principal factor responsible for increased viscosity of blood observed by low shear stress [7].

Those abovementioned changes constitute an important risk factor of cardiovascular disorders in older individuals [8].

Implementation of physical activity regimens, in form of rhythmic exercise to music, can lead to improvement in the hemorheological parameters of older people. Ernst [9] reported considerable improvement of the rheological properties of blood (lower viscosity, favorable changes in elastic properties of erythrocytes) in people with a sedentary lifestyle who started regular physical training.

Compared to people with sedentary lifestyle, trained individuals are characterized by higher concentration of hemoglobin and lower hematocrit level, along with abovementioned reduced viscosity of plasma and whole blood, and higher erythrocyte deformability. The so-called hemodillution phenomenon is postulated to underlie those aforementioned changes [10]. An increase in plasma volume, along with resultant improvement of blood fluidity, are considered training-induced adaptive changes of the circulatory system [11].

Hematological and rheological changes that result from endurance training can considerably improve overall health status of an individual. Therefore, in view of age-related deprivation of hemorheological parameters, older people should be motivated to physical exercise. In current literature there is a lack of evidence regarding influence of dance therapy on the hematological and rheological indicators in older women. Therefore the aim of this study was to analyze the effects of dance therapy on selected hematological and rheological indicators in older women.

2 Materials and method

2.1 Participants

This study included 30 women between 65 and 80 years of age, residents of a nursing home in Cracow, and the control group was comprised of 10 elderly women of corresponding age, living in the same nursing home. The average age of the women from experimental group was 71.8±7.4 years and from control group was 7.1±5.6 years. BMI of the women from experimental group was 27.7.

This study was conducted in accordance with the Declaration of Helsinki (1964). The subjects were familiarized with all the procedures and gave their informed consent to participate in the study. The protocol of this study was approved by the Ethics Committee of the Regional Medical Chamber in Cracow Nr 24 /KBL/OIL/2014.

Women from the control group were not involved in any regular physical activity throughout the five-month period of this study. In contrast, women from the experimental group were subjected to a five-month dance therapy program. The women qualified for the dance therapy program after obtaining approval from their primary care physician and following psychological and physiotherapeutic consultations with specialists employed by their nursing home. Exclusion criteria included paralysis and paresis hindering independent mobility, severe vertigo, dementia, diabetes, cardiovascular disorders, and using drugs that can modulate vascular perfusion. The participants did not use alcohol and nicotine throughout the period of the study.

Cephalic vein blood samples (5 ml) were obtained from all the women prior to the study and five months thereafter, and examined for hematological, rheological, and biochemical parameters. The samples were collected to vacuum tubes with K₂EDTA (1.5 mg/ml).

2.2 Dance therapy program

Women from the experimental group were subjected to a five-month dance therapy program, taking place at their nursing home (three 45-minute sessions per week).

The program was comprised of training proper dancing posture (exercises for normal body posture), slow dancing technique improving all muscle groups equally (exercise involving head and cervical spine, upper limb girdle and arms, trunk, abdominal and back muscles, lower limb girdle and legs), basic steps and figures of folk dance, ballroom dance, integration dance and dances of foreign nations, as well as practicing simple choreographies including previously learned steps and figures, dancing improvisation, and coordination, balance, breathing and relaxation exercises.

The overall pace of training was modulated by music, the character and rhythm of which were adjusted to the age and physical capacity of participants. Additionally, the intensity of training was regulated by the number of repetitions and series of various movements, combining them into larger entities, and the selection and technique of breathing exercise.

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).

2.3 Measurements of hematological parameters

Blood collected in 10μl samples was used to determine basic hematological measurements, and testing was performed using an analyzer for blood (ABX Micros 60 Hematology Analyzer, Horiba ABX Diagnostics, France). The following parameters were determined: red blood cell count (RBC, 10⁶/mm³), hematocrit (HCT, %), hemoglobin concentration (Hb, g/dl), mean corpuscular hemoglobin (MCH, pg), mean corpuscular volume (MCV, μm³), mean corpuscular hemoglobin concentration (MCHC, g/dl), leukocyte count (WBC, 10³/mm³), and platelet count (PLT, 10³/mm³).

2.4 Measurements of plasma viscosity

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

2.5 Biochemical analyses

2.5.1 Fibrinogen concentration

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

2.5.2 Concentration of glucose

Concentration of glucose was measured fasting with an aid of Optium Xido analyzer (Abbott).

2.6 Statistics

Statistical analysis was performed with the aid of Statistica 9.0 (StatSoft^®) package. The normal distribution of continuous variables was tested using the Kolmogorov-Smirnov test. Depending on variable distribution, baseline and post-dance therapy levels of studied parameters were compared using the Student t test for dependent variables or the sign test. The statistical significance was defined as p≤0.05.

3 Results

Blood samples from the women in the control group were re-examined five months after determining the baseline levels of studied parameters. No significant changes in morphological, rheological and biochemical parameters were noted.

3.1 Hematological parameters

The experimental and control groups did not differ significantly in terms of baseline hematological parameters. The dance therapy program was reflected by a significant increase of RBC and HCT in women from the experimental group (Tables 1 and 2).

Table 1
Mean values (±SD) of hematological parameters in the controls and in the experimental group prior to and after the dance therapy program

Parameter Experimental group Control group p Experimental group p

prior to dance therapy after dance therapy

RBC (10⁶/mm³) 4.256±0.353 4.321±0.344 0.9167 4.480±0.626 0.0098^a

Ht (%) 38.780±2.896 38.460±2.378 0.9705 40.830±5.280 0.0104^a

MCH (pg) 30.303±1.610 29.750±2.032 >0.05 30.187±1.690 0.5467

MCHC (g/dl) 33.207±0.945 33.340±1.022 0.9496 33.007±0.561 0.3210

MCV (μm³) 90.897±3.374 89.300±4.322 >0.05 90.862±3.482 0.8390

WBC(10³/mm³) 5.810±1.294 6.767±1.594 >0.05 5.560±1.263 0.2345

PLT (10³/mm ³) 216.655±61.305 213.200±46.789 >0.05 199.448±55.390 0.1863

Parameter	Experimental group	Control group	p	Experimental group	p
RBC (10⁶/mm³)	4.256±0.353	4.321±0.344	0.9167	4.480±0.626	0.0098^a
Ht (%)	38.780±2.896	38.460±2.378	0.9705	40.830±5.280	0.0104^a
MCH (pg)	30.303±1.610	29.750±2.032	>0.05	30.187±1.690	0.5467
MCHC (g/dl)	33.207±0.945	33.340±1.022	0.9496	33.007±0.561	0.3210
MCV (μm³)	90.897±3.374	89.300±4.322	>0.05	90.862±3.482	0.8390
WBC(10³/mm³)	5.810±1.294	6.767±1.594	>0.05	5.560±1.263	0.2345
PLT (10³/mm ³)	216.655±61.305	213.200±46.789	>0.05	199.448±55.390	0.1863

^aSignificantly different compared to value determined prior to dance therapy program.

Table 2

Median values (with interquartile ranges) of hemoglobin concentration (Hb) in the controls and in the experimental group prior to and after the dance therapy program

Parameter	Experimental group	Control group	p	Experimental group	p
	prior to dance therapy			after dance therapy
Hb (g/dl)	12.8 (12.5–13.8)	12.75 (12.3–13.4)	1.0000	12.95 (12.1–14.2)	0.7003

3.2 Plasma viscosity

The experimental and control groups did not differ significantly in terms of baseline plasma viscosity. The dance therapy regimen was reflected by a significant increase in the median plasma viscosity (Table 3).

Table 3
Median values (with interquartile ranges) of blood plasma viscosity (BPV) in the controls and in the experimental group prior to and after the dance therapy program

Parameter Experimental group Control group p Experimental group p

prior to dance therapy after dance therapy

BPV(mPas) 1.245 (1.180–1.380) 1.330 (1.190–1.380) >0.05 1.370 (1.220–1.630) 0.0163^a

Parameter	Experimental group	Control group	p	Experimental group	p
BPV(mPas)	1.245 (1.180–1.380)	1.330 (1.190–1.380)	>0.05	1.370 (1.220–1.630)	0.0163^a

^aSignificantly different compared to value determined prior to dance therapy program.

3.3 Biochemical parameters

No significant differences in fibrinogen and glucose levels were noted between the experimental and control groups prior to this study. Furthermore, no significant changes in these parameters were noted in women from the experimental group who completed the dance therapy program (Table 4).

Table 4
Mean values (±SD) of fibrinogen and glucose concentrations in the controls and in the experimental group prior to and after the dance therapy program

Parameter Experimental group Control group p Experimental group p

prior to dance therapy after dance therapy

Fibrinogen 4.259±1.307 4.138±1.332 >0.05 4.796±1.315 0.4787

Glucose 5.743±0.962 5.410±1.033 0.7185 6.000±1.607 0.2533

Parameter	Experimental group	Control group	p	Experimental group	p
Fibrinogen	4.259±1.307	4.138±1.332	>0.05	4.796±1.315	0.4787
Glucose	5.743±0.962	5.410±1.033	0.7185	6.000±1.607	0.2533

4 Discussion

Lower erythrocyte synthesis rate is a physiological consequence of ageing. With age, a decrease in the volume of bone marrow involved in hematopoiesis is reported. According to the second proposed theory, anemia, the incidence of which is increasing in older people, develops secondarily to various chronic disorders. However, many older individuals with normal health status are characterized by normal blood morphology. Consequently, anemia cannot be considered as a simple characteristic of older age and/or poorer health status [12].

Coppola et al. [13], who studied individuals between 19 and 102 years of age, revealed that subjects older than 60 years were characterized by markedly lower hemoglobin concentration and erythrocyte and thrombocyte counts as compared to younger participants.

Physical training is associated with an array of changes that lead to increase in blood oxygen capacity. Also the positive effect of endurance training manifested by a higher erythrocyte count is a well-documented phenomenon [14]. This association was confirmed by Ahmadizad and El-Sayed [15] and Hu et al. [16], who documented an increase in erythrocyte count in young adults subjected to endurance training.

Due to the lack of any articles about effects of dance therapy on the hematological and rheological indicators in older women, we collected and analysed such data and compared it to the results of researches decribing this influence in regards to other physical activity.

Bobeuf et al. [17] analyzed hematological parameters of older individuals (61–73 years of age) who were subjected to a 6-month regimen of endurance training, and did not observe any significant changes in erythrocyte, thrombocyte and leukocyte counts, hemoglobin concentration, hematocrit levels and MCV, MCH and MCHC. This suggests, that in contrast to young people, endurance training is not reflected by favorable changes in the hematological parameters in the elderly. Bobeuf et al. [17] and Murray-Kolb et al. [18] suggested that this abovementioned lack of response to endurance training can be a direct consequence of ageing. In contrast, our study revealed a significant increase in erythrocyte count (by 5%) and hematocrit levels (also by 5%) in older women who were subjected to dance therapy.

Systematic physical activity can, although not necessarily, modulate function of the immune system. Literature evidence in this matter is inconclusive. In one study, several months of training were not reflected by considerable changes of immune parameters determined at rest [19]. However, other authors [20] observed that training can lead to increase in cytotoxic activity of NK cells measured at rest (12–48 after the exercise). Furthermore, training can contribute to increase in macrophage activity. Peripheral blood macrophages of chronically trained mice (45 minutes of running at 50–75% VO2 max daily, 5 days per week in a 16-week period), when stimulated with interferon gamma and bacterial toxin, killed malignant cells more effectively than the macrophages of control animals [21].

Some authors observed that endurance training can result in higher leukocyte counts, both in young adults [22] and in older women [23]. In contrast, six months of endurance training did not change leukocyte counts of older women and men analyzed by Bobeuf et al. [17]. Also in our study, the exercise was not reflected by higher leukocyte count. Moreover, we did not observe significant changes of other studied morphological parameters: hemoglobin concentration, thrombocyte count, MCV, MCH, and MCHC.

Viscosity of blood plasma is determined mainly by concentration of proteins and blood lipids [24]. The viscosity increases in concert with plasma concentration of non-spherical proteins that are characterized by higher molecular mass, aggregation properties, and sensitivity to temperature, pH and water content changes [25]. Additionally, physiological increase in plasma viscosity is observed with age. Filatova et al. [26] analyzed blood viscosity in apparently healthy subjects of both sexes within the age range from 1 to 75 years. They observed an increase in blood viscosity from infancy to adulthood, followed by a decrease in older age in males. A progressive increase in viscosity was observed in females with aging. However Jung et al. [27] proved that in apparently healthy subjects, there was no increase in plasma viscosity with age, in contrary to data from patients with coronary artery disease.

In most cases, both maximal and submaximal exercise, irrespective of its duration, is reflected by higher blood viscosity, resulting from higher plasma viscosity and higher hematocrit level. Fluid shift from extravascular space into working muscular tissue is reflected by hemoconcentration which is associated with higher values of hematological parameters and elevated concentration of plasma proteins [28]. Vandewalle et al. [29] proved that exercise-induced hemoconcentration constitutes the principle mechanism responsible for an increase in hematocrit level and plasma viscosity. An increase in plasma viscosity observed during the initial hours of intense physical exercise and subsequent decrease of this parameter, markedly below its baseline level, corresponds to considerable dilution of blood. This phenomenon is referred to as “autohemodillution” [11]. An increase in circulating blood volume is observed during subsequent days of endurance training mostly associated with the higher volume of blood plasma. Among others, this favorable adaptive mechanism, improving endurance and fatigue-resistance during prolonged exercise, results from increased stroke volume, higher effectiveness of thermoregulatory mechanisms, and improved hemorheological parameters (lower viscosity and higher fluidity of blood) leading to better muscular perfusion and better oxygen supply of active tissues [30 –32].

Plasma viscosity can be modulated due to consumption of fluids during physical exercise. Marked exercise-induced increase in hematocrit level and concentration of plasma proteins was observed only in those trainees who did not drink any fluids during training; in, contrast, an exercise-induced increase in whole blood and plasma viscosity was less pronounced in individuals who drankwater [33].

Blood viscosity is characterized by a discrete circadian variability [34]. Additionally, blood viscosity can change depending on the type of ingested food products and their water content [35].

In our study, dance therapy resulted in a 12% increase in plasma viscosity. This change could result from a physiological degree of dehydration, losing water with sweat, reluctance to drink fluids during exercise, or a diet deficient in products with a high content of water which are capable of reducing blood viscosity. Furthermore, the blood samples of our participants were collected during morning hours, i.e. at a time of a day characterized by highest hemoconcentration.

According to Hagen-Poiseuille law, increased viscosity of blood is an unfavorable phenomenon since it increases vascular resistance. However, Forconi and Gori [36] revealed that decreased blood viscosity, e.g. due to hemodilution, is not necessarily unfavorable finding. Erythropoiesis, occurring in response to high altitude, is associated with changes in oxygen carrying capacity and may lead to compensatory vasodilatation. Higher viscosity of blood, representing an adaptive mechanism, has positive impact on human health [37].

An increase in blood and plasma viscosity is usually associated with pathological states and increased risk of cardiovascular complications. This hypothesis is partially based on the results of a study which revealed that blood viscosity can increase to extremely high values due to hemoconcentration [37]. Microcirculation impairment results solely from pathologically elevated rheological parameters of blood [38], and the results of recent studies suggests that moderately elevated increase in hematocrit is associated with improved circulation. However, this relationship is non-linear due to changes in peripheral vascular resistance; they result from higher blood viscosity, increase in shear stress and responsive enhanced synthesis of nitric oxide. Similar effect can be observed if plasma viscosity increases due to considerable hemodilution. Microcirculation improvement is observed in both abovementioned cases [37]. Therefore, the positive changes resulting from submaximal exercise, i.e. synthesis of nitric oxide and vasodilatation, may require increase in blood viscosity [39, 40].

Plasma viscosity depends on fibrinogen concentration which increases with age. Fibrinogen concentration reaches the upper limit of its reference value in the elderly, whereas the levels of other plasma proteins do not change considerably [41, 42]. Hager et al. [41] compared concentrations of fibrinogen in individuals below 41 years of age and subjects older than 65 years, and observed that this latter group was characterized by significantly higher (by 44%) values of this parameter. Concentrations of fibrinogen in older individuals can be reduced as a result of physical training [43], and correlate inversely with physical fitness [44].

Lower levels of plasma viscosity in training individuals are mostly ascribed to lower fibrinogen concentrations as compared to untrained subjects [45]. In our study, however, dance therapy was not reflected by significant changes in fibrinogen levels in older women.

Physical exercise is reflected by enhanced synthesis of proteins that transport glucose within muscular cells, leading to improved glucose uptake and glycogen synthesis. Additionally, systematic training improves tissue insulin sensitivity. In subjects with impaired tolerance of glucose, i.e. so-called prediabetes, systematic exercise can delay the development of systematic diabetes or even prevent this condition [46].

However, our study did not reveal statistically significant changes in glucose concentration resulting from implementing the program of rhythmic exercise to music. Also Bobeuf et al. [17] did not observe significant changes in glucose level of 61- to 73-year-old women and men subjected to six-month regimen of endurance training.

5 Conclusions

(1) Dance therapy modulates selected hematological parameters of older women; it leads to increase in erythrocyte count and hematocrit level. In contrast, rhythmic exercise to music is not reflected by significant changes of other hematological parameters. (2) Dance therapy is reflected by higher plasma viscosity. (3) Concentrations of fibrinogen and glucose are not affected by the dance therapy in older women, suggesting maintenance of homeostasis; this observation is particularly favorable in the context of natural age-related tendency to increase in those parameters. (4) Those findings advocate implementation of dance therapy programs in older women.

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