Treadmill Ergometry Research Articles

Rating of Perceived Exertion: A Large Cross-Sectional Study Defining Intensity Levels for Individual Physical Activity Recommendations

BackgroundPhysical inactivity is a growing risk factor worldwide, therefore getting people into sports is necessary. When prescribing physical activity, it is essential to recommend the correct training intensities. Cardiopulmonary exercise testing (CPX) enables precise determination of individuals’ training intensities but is unavailable for a broad population. Therefore, the Borg scale allows individuals to assess perceived exertion and set their intensity easily and cost-efficiently. In order to transfer CPX to rating of perceived exertion (RPE), previous studies investigated RPE on specific physiological anchors, e.g. blood lactate (bLa) concentrations, but representativeness for a broad population is questionable. Some contradictory findings regarding individual factors influencing RPE occur, whereas univariable analysis has been performed so far. Moreover, a multivariable understanding of individual factors influencing RPE is missing. This study aims to determine RPE values at the individual anaerobic threshold (LT2) and defined bLa concentrations in a large cohort and to evaluate individual factors influencing RPE with multivariable analysis.MethodsCPX with bicycle or treadmill ergometer of 6311 participants were analyzed in this cross-sectional study. RPE values at bLa concentrations 2 mmol/l, 3 mmol/l, 4 mmol/l, and LT2 (first rise in bLa over baseline + 1.5 mmol/l) were estimated by spline interpolation. Multivariable cumulative ordinal regression models were performed to assess the influence of sex, age, type of ergometry, VO2max, and duration of exercise testing on RPE.ResultsMedian values [interquartile range (IQR)] of the total population were RPE 13 [11; 14] at 2 mmol/l, RPE 15 [13; 16] at 3 mmol/l, RPE 16 [15; 17] at 4 mmol/l, and RPE 15 [14; 16] at LT2. Main influence of individual factors on RPE were seen especially at 2 mmol/l: male sex (odds ratio (OR) [95%-CI]: 0.65 [0.587; 0.719]), treadmill ergometry (OR 0.754 [0.641; 0.886]), number of stages (OR 1.345 [1.300; 1.394]), age (OR 1.015 [1.012; 1.018]), and VO2max (OR 1.023 [1.015; 1.030]). Number of stages was the only identified influencing factor on RPE at all lactate concentrations/LT2 (3 mmol/l: OR 1.290 [1.244; 1.336]; 4 mmol/l: OR 1.229 [1.187; 1.274]; LT2: OR 1.155 [1.115; 1.197]).ConclusionOur results suggest RPE ≤ 11 for light intensity, RPE 12–14 for moderate intensity, and RPE 15–17 for vigorous intensity, which slightly differs from the current American College of Sports Medicine (ACSM) recommendations. Additionally, we propose an RPE of 15 delineating heavy and severe intensity domain. Age, sex, type of ergometry, duration of exercise, and cardiopulmonary fitness should be considered when recommending individualized intensities with RPE, primarily at lower intensities. Therefore, this study can be used as a new guideline for prescribing individual RPE values in the clinical practice, predominantly for endurance type exercise.

Exercise testing in top athletes

Exercise testing is an essential part of the annual sports medical check-up for competitive athletes. The aim of the examination is to assess the current health status and to perform medical clearance for competitive sports. In addition, assessment of intraindividual changes over time, interindividual comparisons, and determination of training recommendations are of interest. For the assessment of cardiopulmonary fitness, abicycle or treadmill ergometry with ECG recordings is usually conducted. The exercise test is performed according to standardized exercise protocols until maximum individual exhaustion. In competitive sports, understanding of the muscular metabolic situation during exercise is crucial for assessing current exercise capacity and for managing workouts. Therefore, exercise tests are often performed as lactate performance testing or cardiopulmonary exercise test. Lactate performance testing is one of the most frequently used methods regarding exercise testing in competitive sports and is afixed component in most of the annual medical check-ups, which are performed in the sports medicine examination centers of the German Olympic Sports Confederation (DOSB). It enables the analysis of aerobic and anaerobic metabolism during exercise, which allows identification of individual endurance training intensities based on the underlying metabolism. Cardiopulmonary exercise testing is also suitable to determine the maximum oxygen uptake and to better understand medical issues related to exercise capacity.

A Comparison of Anaerobic Power Tests using Cycle Ergometry and Non-motorized Treadmill Ergometry at Optimized Loads

A Comparison of Anaerobic Power Tests using Cycle Ergometry and Non-motorized Treadmill Ergometry at Optimized Loads

The Relationship between Ergometric Treadmill or Bicycle Performance and Isokinetic Trunk Strength - A Retrospective Analysis.

The relationship between trunk strength and athletic performance is well known. In the past, trunk strength and athletic performance were measured in field tests. Previous studies encouraged sport-specific analyses. The goal of this study was to investigate whether there is a relation between ergometrically measured treadmill or bicycle endurance and isokinetic trunk strength. This retrospective analysis included 1334 bicycle and 1838 treadmill ergometry examinations in 1149 subjects. Bicycle and treadmill ergometer performance were analysed in relation to isokinetic trunk strength. Statistics were performed by Pearson correlation and mixed or generalised linear models. Higher treadmill and bicycle power correlated with higher isokinetic trunk strength, with highest absolute trunk strength in the treadmill group. For both running and cycling endurance, a positive correlation with trunk strength could be quantified in regression models. Increased ergometry endurance and lower flexion/extension ratios are connected weakly. Ergometry performance had the strongest correlation with extension trunk strength (r=0.312-0.398 for bicycle ergometry and r=0.168-0.229 for treadmill ergometry, p<0.001). We encourage prospective studies using both kinds of ergometry to evaluate the effect of trunk strengthening to enhance sport-specific endurance performance. Weight-adapted trunk strength values showed overall greater correlation to trunk strength and we recommend the use of weight-adapted values.

Continuous Protein Supplementation Reduces Acute Exercise-Induced Stress Markers in Athletes Performing Marathon.

The aim of this study was to determine the changes in endurance performance and metabolic, hormonal, and inflammatory markers induced by endurance stress (marathon race) in a combined strategy of training and dietary protein supplementation. The study was designed as a randomised controlled trial consisting of regular endurance training without and with a daily intake of a soy protein-based supplement over a three-month period in 2 × 15 (10 males and 5 females per group) endurance-trained adults. Body composition (body mass, BMI, and fat mass) was determined, and physical fitness was measured by treadmill ergometry at baseline and after 3 months of intervention; changes in exercise-induced stress and inflammatory markers (CK, myoglobin, interleukin-6, cortisol, and leukocytes) were also determined before and after a marathon competition; eating behaviour was documented before and after intervention by a three-day diet diary. Although no significant influence on endurance performance was observed, the protein supplementation regime reduced the exercise-induced muscle stress response. Furthermore, a protein intake of ≥20% of total energy intake led to a lower-level stress reaction after the marathon race. In conclusion, supplementary protein intake may influence exercise-induced muscle stress reactions by changing cellular metabolism and inflammatory pathways.

The Relationship Between Cardiorespiratory Fitness and Middle Cerebral Artery Velocity in Women

Age-related declines in cerebral blood flow have been linked to greater risk for cognitive decline. Habitual exercise is recommended to prevent or delay cognitive impairment. Previous studies have found a positive correlation between cardiorespiratory fitness and middle cerebral artery blood velocity (MCAv) in men; however, there is limited data on this relationship in women. This study aimed to examine the relationships between cardiorespiratory fitness, age and MCAv in women. We hypothesized that MCAv would decline with advancing age and there would be a positive association between MCAv and cardiorespiratory fitness in women. Data from 74 women (age = 46 ± 21 y, range = 18 – 83 yrs.) were collected at 4 institutions (University of Kansas Medical Center; University of Wisconsin-Madison; Université Laval; Mayo Clinic) as part of previously conducted studies. All participants were determined to be of low risk for cardiovascular disease according to the American College of Sports Medicine criteria. MCAv, mean arterial pressure, end tidal carbon dioxide and cardiorespiratory fitness (maximal oxygen consumption: VO2max) were retrieved from study records. MCAv was collected unilaterally at rest using a transcranial Doppler ultrasound. VO2max was collected during either cycling ergometry (n = 61) or treadmill ergometry (n = 13) tests. Associations were assessed using a Pearson product-moment correlation. In the 74 women, the absolute VO2max was 2089 ± 622 ml·min-1 and average relative VO2max was 34 ± 10 ml·kg-1·min-1. The average MCAv for the entire group was 64 ± 16 cm·s-1. As expected, there was an inverse association between age and MCAv (r = -0.310; p = 0.007) such that women who were older demonstrated lower MCAv. There was a positive association between absolute VO2max and MCAv (r = 0.310; p = 0.007). Likewise, there was a positive association between relative VO2max and MCAv (r = 0.309; p = 0.007) such that women with higher cardiorespiratory fitness demonstrated higher MCAv. However, the relationship between VO2max and MCAv was no longer significant when adjusted for age (absolute VO2max; r = -0.105, p = 0.375; relative VO2 max; r = -0.089, p = 0.452). Cardiorespiratory fitness is positively associated with MCAv in women. This suggests that habitual exercise may be protective against age-related declines in cerebral blood flow. However, because the association between cardiorespiratory fitness and MCAv is attenuated when it is adjusted for age, future studies could utilize non-linear modeling to understand how age, MCAv and cardiorespiratory fitness are related in women.

Improved Exercise Tolerance and Lung Function in Women with LAM Following Three Months of Exercise Training

Rationale: While exercise has been shown to improve respiratory symptoms, exercise tolerance, and bone mineral density in many populations, no supervised exercise training interventions have been undertaken in patients with lymphangioleiomyomatosis (LAM). Objectives: To assess the effects of a supervised exercise intervention on exercise tolerance, pulmonary function, and bone mineral density in patients with LAM. Methods: subjects with LAM (Sporadic LAM n=7; TS-LAM n=1) enrolled in the study. Subjects participated in two weekly supervised aerobic exercise training (50-60 minutes) at 80-85% heart rate max for 12 weeks. Heart rate and oxygen saturation levels were monitored throughout the intervention. Treadmill ergometry (VO2peak), spirometry (FEV1, FVC, FEV1/FVC, FEV1 predicted, peak flow), and bone mineral density assessments were performed prior to and 12 weeks after initiation of intervention. Measurements and Main Results: After 12 weeks of supervised aerobic exercise training, group mean improvements were seen in all outcomes including VO2peak, FEV1, FVC, FEV1/FVC, FEV1 predicted, peak flow, and whole body bone mineral density. Conclusions: Results from this study indicate that supervised exercise training can improve exercise tolerance, pulmonary function, and bone mineral density in patients with lymphangioleiomyomatosis. Further research is needed, including longitudinal studies with larger sample sizes, to determine long-term effects and consistency of these findings. Aerobic exercise may offer a viable alternative to, or work in conjunction with, pharmacological intervention in the treatment of lymphangioleiomyomatosis.

Incidence and severity of postthrombotic syndrome after iliofemoral thrombosis - results of the Iliaca-PTS - Registry.

Background: Deep venous thrombosis (DVT) and in particular, iliofemoral thrombosis (IFT) can lead to recurrent thrombosis and postthrombotic syndrome (PTS). Data on the prevalence, predictors and outcome of IFT are scarce. Patients and methods: We retrospectively searched our database of outpatients who had presented with DVT and IFT including the iliac veins from 2014 until 2017. In addition, we performed a prospective registry in a subgroup of patients with IFT. These patients received duplex ultrasound, magnetic resonance venography and measurement of symptom-free walking distance using a standardized treadmill ergometry. The severity of PTS was analyzed using the Villalta-Scale (VS) and quality of life was assessed using the VEINES-QOL/Sym Questionnaire. Results: 847 patients were retrospectively identified with DVT and 19.7% (167/847) of these presented with IFT. 50.9% (85/167) of the IFT-patients agreed to participate in the prospective registry. The majority of these patients (76.5%: 65/85) presented with left-sided IFT. In 53.8% (35/65) May-Thurner syndrome was suspected. 27.1% (23/85) underwent invasive therapy. Moderate or severe PTS (VS≥10) occurred in 10.6% (9/85). The severity of PTS is correlated with a reduced quality of life (ρ (CI 95%)=-0.63 (-0.76; -0.46); p<0.01). None of the patients presented with a venous ulcer at any time. A high body mass index was a significant predictor (OR (CI 95%)=1.18 (1.05; 1.33), p=0.007) for the development of clinically relevant PTS (VS≥10) and venous claudication. Conclusions: Every fifth patient with DVT presented with an IFT. The majority developed left sided IFT. Every 10th patient developed moderate or severe PTS (VS≥10). A high body mass index was predictive for the development of PTS and venous claudication.

Feasibility and results of an intensive cardiac rehabilitation program. Insights from the MxM (Más por Menos) randomized trial

Introduction and objectivesCardiac rehabilitation programs (CRP) are a set of interventions to improve the prognosis of cardiovascular disease by influencing patients’ physical, mental, and social conditions. However, there are no studies evaluating the optimal duration of these programs. We aimed to compare the results of a standard vs a brief intensive CRP in patients after ST-segment elevation and non–ST-segment elevation acute coronary syndrome through the Más por Menos study (More Intensive Cardiac Rehabilitation Programs in Less Time). MethodsIn this prospective, randomized, open, evaluator-blind for end-point, and multicenter trial (PROBE design), patients were randomly allocated to either standard 8-week CRP or intensive 2-week CRP with booster sessions. A final visit was performed 12 months later, after completion of the program. We assessed adherence to the Mediterranean diet, psychological status, smoking, drug therapy, functional capacity, quality of life, cardiometabolic and anthropometric parameters, cardiovascular events, and all-cause mortality during follow-up. ResultsA total of 497 patients (mean age, 57.8±10.0 years; 87.3% men) were finally assessed (intensive: n=262; standard: n=235). Baseline characteristics were similar between the 2 groups. At 12 months, the results of treadmill ergometry improved by ≥ 1 MET in ≥ 93% of the patients. In addition, adherence to the Mediterranean diet and quality of life were significantly improved by CRP, with no significant differences between the groups. The occurrence of cardiovascular events was similar in the 2 groups. ConclusionsIntensive CRP could be as effective as standard CRP in achieving adherence to recommended secondary prevention measures after acute coronary syndrome and could be an alternative for some patients and centers.Registered at ClinicalTrials.gov (Identifier: NCT02619422).

Factibilidad y resultados de un programa de rehabilitación cardiaca intensiva. Perspectiva del estudio aleatorizado MxM (Más por Menos)

Introduction and objectivesCardiac rehabilitation programs (CRP) are a set of interventions to improve the prognosis of cardiovascular disease by influencing patients’ physical, mental, and social conditions. However, there are no studies evaluating the optimal duration of these programs. We aimed to compare the results of a standard vs a brief intensive CRP in patients after ST-segment elevation and non–ST-segment elevation acute coronary syndrome through the Más por Menos study (More Intensive Cardiac Rehabilitation Programs in Less Time). MethodsIn this prospective, randomized, open, evaluator-blind for end-point, and multicenter trial (PROBE design), patients were randomly allocated to either standard 8-week CRP or intensive 2-week CRP with booster sessions. A final visit was performed 12 months later, after completion of the program. We assessed adherence to the Mediterranean diet, psychological status, smoking, drug therapy, functional capacity, quality of life, cardiometabolic and anthropometric parameters, cardiovascular events, and all-cause mortality during follow-up. ResultsA total of 497 patients (mean age, 57.8±10.0 years; 87.3% men) were finally assessed (intensive: n=262; standard: n=235). Baseline characteristics were similar between the 2 groups. At 12 months, the results of treadmill ergometry improved by ≥ 1 MET in ≥ 93% of the patients. In addition, adherence to the Mediterranean diet and quality of life were significantly improved by CRP, with no significant differences between the groups. The occurrence of cardiovascular events was similar in the 2 groups. ConclusionsIntensive CRP could be as effective as standard CRP in achieving adherence to recommended secondary prevention measures after acute coronary syndrome and could be an alternative for some patients and centers.Registered at ClinicalTrials.gov (Identifier: NCT02619422).

Development of peak oxygen uptake from 11\u201316 years determined using both treadmill and cycle ergometry

PurposesTo investigate the development of peak oxygen uptake (dot{{V}}{text{O}}_{2}) assessed on both a treadmill and a cycle ergometer in relation with sex and concurrent changes in age, body mass, fat-free mass (FFM), and maturity status and to evaluate currently proposed ‘clinical red flags’ or health-related cut-points for peak dot{{V}}{text{O}}_{2}.MethodsMultiplicative multilevel modelling, which enables the effects of variables to be partitioned concurrently within an allometric framework, was used to analyze the peak dot{{V}}{text{O}}_{2}s of 138 (72 boys) students initially aged 11–14 years and tested on three annual occasions. Models were founded on 640 (340 from boys) determinations of peak dot{{V}}{text{O}}_{2}, supported by anthropometric measures and maturity status.ResultsMean peak dot{{V}}{text{O}}_{2}s were 11–14% higher on a treadmill. The data did not meet the statistical assumptions underpinning ratio scaling of peak dot{{V}}{text{O}}_{2} with body mass. With body mass appropriately controlled for boys’ peak dot{{V}}{text{O}}_{2}s were higher than girls’ values and the difference increased with age. The development of peak dot{{V}}{text{O}}_{2} was sex-specific, but within sex models were similar on both ergometers with FFM the dominant anthropometric factor.ConclusionsData should not be pooled for analysis but data from either ergometer can be used independently to interpret the development of peak dot{{V}}{text{O}}_{2} in youth. On both ergometers and in both sexes, FFM is the most powerful morphological influence on the development of peak dot{{V}}{text{O}}_{2}. ‘Clinical red flags’ or health-related cut-points proposed without consideration of exercise mode and founded on peak dot{{V}}{text{O}}_{2} in ratio with body mass are fallacious.

Comparison of Anaerobic Power Tests During Cycle and Non-Motorized Treadmill Ergometry at Optimized Loads.

Comparison of Anaerobic Power Tests During Cycle and Non-Motorized Treadmill Ergometry at Optimized Loads.

127 Relationship between plasma concentrations of b-type natriuretic peptide and exercise capacity in hypertrophic cardiomyopathy

BackgroundHypertrophic cardiomyopathy (HCM) is characterised by increased left ventricular wall thickness leading to exercise intolerance and heart failure. Peak oxygen consumption (peak VO2) on cardiopulmonary exercise testing (CPET) is often...

Consistency of Peak Fat Oxidation Rates During Treadmill Ergometry: A Pilot Protocol and Methodological Elaborationt

Consistency of Peak Fat Oxidation Rates During Treadmill Ergometry: A Pilot Protocol and Methodological Elaborationt

Accuracy of Wrist-Worn Activity Monitors during Treadmill and Elliptical Ergometry

Accuracy of Wrist-Worn Activity Monitors during Treadmill and Elliptical Ergometry

Assessment of Arm Crank and Wheelchair Treadmill Ergometry in Wheelchair Basketball Players

Assessment of Arm Crank and Wheelchair Treadmill Ergometry in Wheelchair Basketball Players

Profiling Sprint Mechanics by Leg Preference and Position in Rugby Union Athletes

Lower-extremity power characteristics are central to performance in rugby. However little is known regarding the effects of leg preference and playing position on sprint mechanics. The purpose of this study was to profile sprint kinetics and kinematics in rugby union athletes and compare between legs and between positions. Thirty male academy-level rugby union athletes, separated into forwards (n=15) and backs (n=15), participated in this cross-sectional analysis. Non-motorised treadmill ergometry was used to evaluate peak relative vertical (FV) and horizontal (FH) force and peak relative power (Pmax) of the preferred and non-preferred legs during maximal sprinting. The non-preferred leg of the forwards produced less FV, FH and Pmax than the preferred leg during acceleration (ES=-0.32, - 0.58 and - 0.67) and maximal velocity (ES=- 0.50, - 0.65 and - 0.60). Backs produced more FV, FH and Pmax than the forwards during initial acceleration (ES=0.51, 1.58 and 1.30) but less at maximal velocity (ES=- 0.74, -0.79 and - 0.81). Backs had faster split times at 2, 5, 10 and 15 m (ES=-1.03, -0.82, -0.63 and -0.50) but slower times at 35 and 40 m (ES=0.78 and 1.10) compared with forwards. Forwards produced larger sprint kinetics compared with backs, but also larger lower-extremity imbalances; potentially reducing sprint efficiency and/or increasing injury risk.

Reliability and day-to-day variability of peak fat oxidation during treadmill ergometry

BackgroundExercising at intensities where fat oxidation rates are high has been shown to induce metabolic benefits in recreational and health-oriented sportsmen. The exercise intensity (Fatpeak) eliciting peak fat oxidation rates is therefore of particular interest when aiming to prescribe exercise for the purpose of fat oxidation and related metabolic effects. Although running and walking are feasible and popular among the target population, no reliable protocols are available to assess Fatpeak as well as its actual velocity (VPFO) during treadmill ergometry. Our purpose was therefore, to assess the reliability and day-to-day variability of VPFO and Fatpeak during treadmill ergometry running.MethodsSixteen recreational athletes (f = 7, m = 9; 25 ± 3 y; 1.76 ± 0.09 m; 68.3 ± 13.7 kg; 23.1 ± 2.9 kg/m2) performed 2 different running protocols on 3 different days with standardized nutrition the day before testing. At day 1, peak oxygen uptake (VO2peak) and the velocities at the aerobic threshold (VLT) and respiratory exchange ratio (RER) of 1.00 (VRER) were assessed. At days 2 and 3, subjects ran an identical submaximal incremental test (Fat-peak test) composed of a 10 min warm-up (70 % VLT) followed by 5 stages of 6 min with equal increments (stage 1 = VLT, stage 5 = VRER). Breath-by-breath gas exchange data was measured continuously and used to determine fat oxidation rates. A third order polynomial function was used to identify VPFO and subsequently Fatpeak. The reproducibility and variability of variables was verified with an intraclass correlation coefficient (ICC), Pearson’s correlation coefficient, coefficient of variation (CV) and the mean differences (bias) ± 95 % limits of agreement (LoA).ResultsICC, Pearson’s correlation and CV for VPFO and Fatpeak were 0.98, 0.97, 5.0 %; and 0.90, 0.81, 7.0 %, respectively. Bias ± 95 % LoA was −0.3 ± 0.9 km/h for VPFO and −2 ± 8 % of VO2peak for Fatpeak.ConclusionIn summary, relative and absolute reliability indicators for VPFO and Fatpeak were found to be excellent. The observed LoA may now serve as a basis for future training prescriptions, although fat oxidation rates at prolonged exercise bouts at this intensity still need to be investigated.

An Evaluation of the Significance of Work-Related Influence Factors on Fitness and the Development of Medical and Orthopaedic Conditions in Military Executives.

Occupational health promotion is an effective tool to improve the state of health of employees. As part of occupational health promotion in the German Bundeswehr, top-ranking military executives are offered a medical examination and training programme. Health-related data is collected as a basis for training and lifestyle counselling. This data was subjected to a retrospective evaluation in order to identify occupational risk factors and their correlation with cardiovascular resilience, trunk strength, and the development of orthopaedic and internal disorders. A total of 122 military executives (all male, age 54.6 ± 4.2 years) answered a questionnaire aimed at evaluating private and occupational stress factors. The medical history was followed by a medical and orthopaedic examination involving a lactate performance test (treadmill or bicycle ergometry) and an isometric trunk strength measurement. The data obtained was then statistically evaluated. For military executives, work-related travelling and commuting involve a high risk of medical and orthopaedic conditions. Regular exercise leads to improved fitness levels. In order to prevent medical problems, military executives working long hours should regularly take part in fitness and weight training under professional instructions.

Interrelation of the heart rate turbulence with the clinical, functional and morphometric parameters among the patients with arterial hypertension

There have been explored 225 males in the age from 50 to 74 with an arterial hypertension (AH). For all the patients there have been carried out the recording of electrocardiogram (ECG) in the state of rest, ECG monitoring with a Holter identify indicators heart rate turbulence (HRT) and dynamic load testing (test with a 6 minute walk test, treadmill and bicycle ergometry). There was founded, that among the patients with an arterial hypertension after 50 years the number of ventricular premature beats grows up. With increasing of the age the normal values decrease and the pathological values increase heart rate turbulence (HRT), average slope of turbulence slope (TS). Dynamic load testing of patients after 70 years shows an increase in common, stress-induced ventricular arrhythmia, which is associated with ischemic-segment ST. Among the patients with arterial hypertension and frequent load-induced ventricular premature beats, in comparison with a rare, indicators of the HRT have a higher value. HRT among the patients with an arterial hypertension has a relationship with clinical and functional morfomerical indicators. The values turbulence onset (TO) of these were linked to the index left ventricular mass, pulse pressure, the number of ventricular premature beats, the average hemodynamic blood pressure, age and the values of circadian index (CI). The indicators TS are associated with index left ventricular mass, pulse pressure, the number of ventricular premature beats, with an average hemodynamic blood pressure, c values of the age and circadian index (CI).