THE ImpACT OF INDOOR CYCLING TRAINING ON HEmODYNAmIC pARAmETERS OF THE LEFT VENTRICLE OF mEN WITH ISCHAEmIC HEART DISEASE OR AFTER mYOCARDIAL INFARCTION

Aim. Younger age of the cardiac patients somehow necessitates the use of modern forms of physical training, which become alternative and interesting means to provide effective rehabilitation. One such form is endurance Indoor Cycling training. In the present study attempts to determine the impact of 1-month Indoor Cycling training on hemodynamic left ventricle parameters of men with ischemic heart disease or after myocardial infarction were made. material and methods. The study group consisted of 50 men under the model A of the 2 nd phase of cardiac rehabilitation (20 men of the Indoor Cycling group, IC, 20 men rehabilitated accordingly to the recommendations of the Polish Cardiac Society — a standard group, ST and 10 people who did not participate in any cardiac rehabilitation program — a control group, C). The average age of all patients was 56,60±8,25 years, the average left ventricular ejection fraction was 56%±4,00. Results. Echocardiogram did not show significant changes after 1-month of training in both groups undergoing comprehensive cardiac rehabilitation. Paralleled to the preliminary study in the group of patients who refused to participate in the cardiac rehabilitation, results showed a reduction in all echocardiographic parameters, including a significant decrease in the left ventricular end diastolic diameter (52,80 vs 50,50 mm) and volume (134,85 vs 121,88 ml; both variables at p<0,001), as well as in the left ventricular mass (239,46 vs 208,61 g; p=0,002) and the left ventricular mass index (123,52 vs 107,61 g/m 2 ; p=0,001). Conclusion. No negative influence of the Indoor Cycling training on morphological parameters of the left ventricle was observed. Indoor Cycling training in the second phase of cardiac rehabilitation in patients with ischemic heart disease or after myocardial infarction is a safe form of therapy and therefore may be an interesting alternative method to the classic bicycle ergometer exercise in the stage of an early cardiac rehabilitation.

High prevalence of cardiovascular diseases (on the one hand caused by the adverse impact of civilization, on the other -the increase of survival associated with the dynamic development of medicine, including cardiology) caused an increased significance of secondary prevention and rehabilitation. Evaluation of invasive cardiology methods, the use of new surgical techniques and conservative treatment (including dissemination of anticoagulation and fibrinolysis) have contributed to reduction of mortality from cardiovascular diseases [1][2][3].
will diversify rehabilitation program, on the other, there would be a better possibility to choose an appropriate load depending on the model of improvement [10].
The Indoor Cycling training of healthy individuals has several basic types of profiles -from least, through medium to strongly incriminating. Properly conducted training consists of a warm-up, an appropriate training and an end portion -crossover and stretching, which concerns proper muscle groups and tendons, especially legs, arms and the spine. Indoor Cycling training can be carried out in three basic positions of the hands, in sitting or standing techniques [10][11][12][13]. So far, there are no reports of the use of Indoor Cycling training as an alternative form to the traditional and commonly used endurance cycle ergometer training of patients after coronary events, which tends to analyze the effectiveness of this form of physical training. The study attempts to determine the impact of the 22 Indoor Cycling training units (1-month) on hemodynamic parameters of the left ventricle patients' with ischaemic disease or after myocardial infarction.

material and methods
The study group consisted of 50 men under the model A of the second phase of cardiac rehabilitation (results of exercise treadmill test ≥7 MET or 100 W). Groups were comparable in terms of age, body height, body weight and left ventricular ejection fraction. Their characteristics are Nowadays, primary aim is to reduce mortality, however the purpose is also to counteract secondary prevention of relapse and repeated cardiac episodes, and rehabilitationthe desire to restore the full quality of life of the patient, facilitating return to active and family life [2,4]. Therefore, logical and desirable seems to be a modification of cardiac rehabilitation, especially applied forms of physical training.
According to Cardiac Rehabilitation Standards of Polish Cardiac Society, traditional and commonly used training forms are endurance training in the form of walking on the treadmill or in the field, a bicycle ergometer training, swimming, training on the lifecycle and anaerobic resistance training. In patients with coronary artery events, both of these forms combined together provided the best results [5][6][7][8].
Physical training, which begins in the second stage of cardiac rehabilitation, is well understood and described, but rare publications on the use of modern, innovative forms of exercises for patients with cardiovascular diseases can be found. Younger age of the cardiac patients somehow necessitates the use of modern forms of physical training, which become an interesting and attractive means to provide effective process of recovery [9]. One such form is an endurance training, which in a sense resembles the traditional practice recommended for the second stage of the rehabilitation, but with a slightly different course -Indoor Cycling. On the one hand the use of this training  shown in Table 1. 100% of patients experienced ischemic heart disease, 74% of them had a myocardial infarction ( Table 2). The prevailing type of treatment in the study population was percutaneous coronary intervention (PCI) combined with implantation of 1 stent (Table 3 and 4). Inclusion criteria were: formal consent to participate in the study, stable coronary heart disease or uncomplicated course of myocardial infarction, time of last cardiovascular event not less than2 months and not more than 6 months, an exercise test results ≥7 MET / 100 W, left ventricular ejection fraction ≥50%. Exclusion criteria were: lack of formal consent to participate in the study, recent myocardial infarction, <2 months of a cardiovascular event, left ventricular ejection fraction <50%, the surgical treatment of coronary artery disease (CABG), unregulated hypertension, unstable ischemic heart disease, arrhythmias, diagnosed cancer, diseases of the central or peripheral nervous system, varicose veins of the lower limbs, degenerative disease of the peripheral joints and spine, past unhealed injuries of the lower limbs, advanced peripheral vascular disease, age ≥75 and incomplete medical documentation.
Between November 2014 and January 2015, reducing the number of confounding factors such as age, sex, disease entity, method of treatment, the level of exercise capacity, 50 patients enrolled in the study were allocated according to random selection into the three groups: 20 men, members of the Indoor Cycling group, IC, 20 men rehabilitated accordingly to the recommendations of the Section of Cardiac Rehabilitation and Physiology Effort Polish Cardiac Society -a standard group, ST and 10 people who did not participate in any cardiac rehabilitation program -a control group, C). Patients (except from the C group) underwent 22 training units performed 5 times a week (1 month). In the ST group the training included: endurance exercise on a bicycle ergometer, resistance training and calisthenics (general exercises). Whereas men in the IC group, instead of the traditional interval training on the ergometer, participated in the Indoor Cycling lessons arranged by the same instructor (Table 5, Figure 1). That group also participated in the other two types of trainings (resistance and calisthenics) according to the standards (Table 6). Heart rate frequency was constantly individually monitored during each lesson by the heart rate monitor (Polar FT1), as well as by the instructor.
At baseline and at the end of the rehabilitation period all patients underwent echocardiographic measurements, where the left ventricular mass was calculated as defined underneath.
The echocardiographic evaluation was performed with the patient lying in the left decubitus position, by one Table 3 The method of treatment in the Indoor Cycling, standard and control group Method     For all numerical parameters the arithmetic mean, minimum, maximum and standard deviation were calculated. For the presentation of qualitative data the prevalence of studied traits were used. In order to verify assumptions of tests the Shapiro-Wilk normality test was performed. For the    Table 7 shows results of the echocardiographic measurements in the three groups of patients before (I) and at the end (II) of cardiac rehabilitation.

The
Echocardiogram did not show significant changes after 1-month of training in Indoor Cycling and standard group. Noteworthy is, that in both groups undergoing comprehensive cardiac rehabilitation value of the LVEF was insignificantly higher than in the beginning (56,05 vs 57,20% in IC group and 56,10 vs 57,35% in ST group).
The analysis also showed significant differences in Δ results between groups (Δ of LVEDD, LVEDV, LVM and LVMI between IC, S and C group, as well as in Δ of LVEF among standard and control group).

Discussion
Echocardiography is considered a clinically relevant, non-invasive structures and function of the heart evaluation. Echocardiography should precede qualification Table 7 Results of the echocardiography test in three groups of patients before (I) and at the end (II) of cardiac rehabilitation  for rehabilitation because of the non-invasive character of the assessment of important parameters affecting the safety of its course (left ventricle ejection fraction or indicators of abnormal pressure and blood flow within the heart muscle cavities). The result of myocardial infarction and coronary artery disease is the impairment of mechanical myocardial function and progressive structural changes in the heart muscle (called remodeling), which affect all parts of the cardiovascular system equally [15]. Altered hemodynamic conditions (for instance reduction of stroke volume, enhancement of end-diastolic volume) and neurohormonal disorders (increased activity of the renin-angiotensinaldosterone as well as catecholamines) consistently contribute to impaired diastolic function of the heart, thus affecting systolic function with reduction of LVEF at the same time. Postinfarction cardiac remodeling, specifically -larger figure of the left ventricle may be an important factor for an unfavorable prognosis, and therefore assess its dimensions and functions should be performed routinely in most cardiac diseases [16]. In turn, postinfarction extension of the right ventricle can indicate the pressure and volume overload [15,16].
This paper presents an evaluation of left ventricular myocardium indicators. Our analysis shown insignificant increases in average values of LVEDD, LVESD, LVEDV, LVESV, LVM, LVMI, LVEF, and minor decrease of left LVSV in both rehabilitated groups after 22 training units. In turn, in the group of patients who refused to participate in the comprehensive cardiac rehabilitation achieved reduction of all these indicators and occurred significant changes in the case of LVEDD, LVEDV, LVM and LVMI. It should be emphasized that determine the influence of physical activity (primarily an endurance type) on postinfarction structure and functions of left ventricle remains still ambiguous [17]. Primarily, the causes of this problem may be differences in the methodology of the study carried out by subsequent authors (factors such as: selection of the population, the extent of myocardial infarction, age of the respondents, the period covered by the observation, measurement techniques and the combination of all mentioned factors as possible).
According to the Karpiński and Witkowska (2009) the end systolic volume in patients after myocardial infarction is strongly correlated with mortality and the incidence of postinfarction heart failure [15]. In the other site, Korzeniowska-Kubacka et al. (2010) claim that the left ventricular diastolic function may be an important factor of an increase in exercise tolerance after a period of rehabilitation [18]. It is not resolved whether exercise training used in cardiac rehabilitation can improve diastolic function of the left ventricle [18]. Gates et al. (2003) noted that regular physical activity does not stimulate changes in diastolic function of the left ventricle in healthy aging men. Observation of Gates et al. coincident with the result obtained in our control group, in which after the observation period was a significant reduction in boththe LVEDD and the LVEDV (p<0,001) [19]. Belardinelli et al. (2001) did not notice significant changes in the left ventricle diastolic function in physically active patients compared with inactive, in the course of the 6-month follow-up. However, they differed significantly in the LVESV after this period (40,8 in training group vs 48,8 ml in inactive group; p<0,009). Whereas the indicator which clearly differentiating patients after 6 months observation was the LVEF. Authors noted that in active patients LVEF increased from 52,3 to 57,3%, while in sedentary lifestyle patients LVEF slightly reduced from 50,2 to 49,3%, which is consistent with changes observed in our analysis [20].
LVEF is a clinical indicator of global myocardial contractility and pumping action. Moreover, it is one of the most important prognostic parameters in patients after myocardial infarction [21,22]. Postinfarction myocardial range of the left ventricle remodeling can be measured by the LVEF obtained from the echocardiogram. Among the many advantages of comprehensive cardiac rehabilitation, positive impact on this indicator is also mentioned [6].  analyzed the impact of 8-week cardiac rehabilitation program in 70 patients with ischemic heart disease and left ventricular dysfunction. Authors evaluated changes in indicators such as: LVEF, LVESD and LVEDD. Mentioned authors demonstrated that the LVEF increased significantly from 45,14 to 50,44% (p<0,001). However, there were no significant changes in the LVEDD (54,63 vs 53,86 mm) and the LVESD (38,91 vs 38,09 mm) parameters after the rehabilitation program. Therefore, authors concluded that exercise training in patients with ventricular dysfunction may have beneficial effects on cardiac function, at the same time without adversely affecting the reconstruction of the left ventricle and causing no serious cardiac complications [23]. Similar results obtained Nowak et al. (2010) who after the 6-month follow-up reported a significant increase in the LVEF (51,64 vs 52,45%, p<0,02) and no significant changes in the LVEDD (51,10 vs 51,35 mm) and LVESD (34,93 vs 34,33 mm) indicators [24]. The direction of changes observed by these authors is consistent with our results in which LVEDD and LVESD parameters were not significantly different after 22 training units in the Indoor Cycling and standard group and the LVEF value of these groups was an irrelevant, but still an increase of more than 1%. In patients undergoing comprehensive cardiac rehabilitation are expected to further increase in LVEF parameter in accordance with the fact of the left ventricular contractility improvement. Haddadzadeh et al. (2011) in turn, analyzed the effectiveness of individually selected program of cardiac rehabilitation in 42 patients with coronary heart disease. The authors obtained a significant improvement of the LVEF in patients receiving 12-week program for rehabilitation enriched by the exercise training (46,9 vs 61,5%; p=0,001), compared to the control group, which lacked an element of physical activity in rehabilitation program (47,9 vs 47,6%) [21]. On the other hand, Markuszewski et al. (2006) evaluated the impact of type 2 diabetes on postinfarction myocardial remodeling in patients after myocardial infarction with ST-segment elevation treated by percutaneous transluminal coronary angioplasty (PTCA). Authors compared the changes in the parameters of the left ventricle -LVEF, LVEDV, LVESV in 110 people. It has been shown that after 3 months of myocardial infarction in patients with type 2 diabetes and patients without that disease was significantly reduced LVEF and significantly increased LVESV value. Because patients with diabetes often suffer from other conditions such as hypertension and obesity as well as a biochemical metabolic disorders which have a negative impact on left ventricular diastolic function are occurred equally, in the case of such patients should be considered implementation of controlled and systematic physical activity. Negative changes observed in the Markuszewski et al. analysis were not present in our work, in which type 2 diabetes occurred in 22% of the total study population [22].
Further analyzed indicators were the LVM and the LVMI. According to Nowak (2006) LVM is an independent prognostic factor of overall mortality from cardiac causes and complications of coronary artery disease in people over the age of 40 and LVMI -used to assess the degree of left ventricular myocardium hypertrophy [25]. LVM is proportional to the body. It can refer to the weight (kg) growth (m) or body surface area (m 2 ). The increase of LVM resulting from the hypertrophy is an important risk factor for heart failure and reduction of LVEF value [16]. According to Pitsavos et al. (2011) physical activity associated with leisure time is correlated with reduction of the LVM. Our analysis showed a slight increase in LVM and LVMI in both cardiac comprehensive rehabilitation groups. Noteworthy is fact that in the Indoor Cycling and standard group average value of LVMI was lower than 116 kg/m 2 classified as a moderate left ventricular hypertrophy [26]. An interesting change can be observed in the case of patients who refused to participate in the rehabilitation program, in which the average value of LVMI was significantly reduced (123,52 vs 107,61 g/m 2 ; p=0,001), as well as LVM (239,46 vs 208,61 g; p=0,002). These observations differ from the analysis Pitsavos et al. (2011), who evaluated the effect of a regular 16-week physical training on the cardiovascular system of middle age men with normal or moderately elevated blood pressure. It should be emphasized, that these patients had no clinical signs of coronary artery disease, which in the case of the control group in our analysis, is essential. After the observation period the average value of LVM and LVMI in physically active group significantly decreased (225,10 [24]. The overall conclusion is that the effect of exercise training on myocardium has not been clearly explained yet. In most studies, as in the present could not be demonstrated a significant influence of exercise training on the morphological and functional ventricular parameters or confirmed that physical activity improved it irrelevantly (in particular, with reference to a preferred change in left ventricle ejection fraction). However, it should be noted that in the control groups, which have not undergone training often been reported deterioration of left ventricular function of the heart muscle during the observation period.

Conclusion
In conclusion, no negative impact of the Indoor Cycling training on morphological parameters of left ventricle of men with ischemic heart disease or after myocardial infarction was found. Analysis shown that Indoor Cycling is a safe, engaging, effective and welltolerated form of endurance training, which would expand the range of activities recommended in the comprehensive cardiac rehabilitation beginning in the second stage. Further studies are needed to define the long-term effects of use this form of physical activity as well as the introduction of Indoor Cycling in women after coronary events.