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A Deligiannis

Publications and source records attributed to A Deligiannis.

At least 19 recordsLinked to original sources
PubMed2005

Cardiac function after exhaustive open-sea swimming.

AIM: The present study examined the acute effects of exhaustive 25-km open-sea swimming on left ventricular (LV) function and morphology. METHODS: Twenty elite male swimmers (22.3+/-4.1 years) participated in this study. Two-dimensionally guided M-mode echocardiograms, and electrocardiographic, phonocardiographic and carotid pulse tracings were performed simultaneously before and immediately after prolonged exhaustive swimming to evaluate the LV function and morphology, and the cardiac sympathetic outflow. Blood samples were also collected before and after the race to determine the hematocrit and the plasma concentrations of K+, Na+, Ca2+, a-ANP, renin, myoglobulin, CPK-MB, and lactate. RESULTS: Exhaustive swimming was associated with a significant reduction in LV fractional shortening (-13%), ejection fraction (-11%), stroke volume (-25%), and LV internal diastolic diameter (-7%). In contrast, cardiac index was increased by 31%, total peripheral resistance was increased by 7%, and LV circumferential and meridional wall stresses were increased by 101% and 102%, respectively. Significant relationships were found between the increases in total peripheral resistance and LV circumferential wall stress and the decrease in ejection fraction. On the contrast, no significant relationship was found between the increased hematocrit and decreased ejection fraction. Furthermore, the pre-ejection period increased by 11%, the pre-ejection period to LV ejection time ratio increased by 15%, and the electrical to electromechanical systole relationship increased from -8 to 10 ms. Immediately after the race, there were significant increases in hematocrit (9%), and plasma concentrations of a-ANP (211%), renin (161%) and lactate (72%), myoglobulin (421%), and CPK-MB (141%) compared to pre-race values. CONCLUSIONS: In elite athletes, prolonged exhaustive swimming is associated with depressed LV function, as suggested by reduced stroke volume, ejection fraction, and LV fractional shortening. This alteration is mainly due to increased afterload.

Adult↗
PubMed2004

Outcomes of long-term exercise training in dialysis patients: comparison of two training programs.

BACKGROUND: Exercise training has been shown to improve the low functional capacity and quality of life in dialysis (HD) patients. However, there are no data about the outcome of long-term exercise training and, also, the adherence of HD patients in such long-term renal rehabilitation programs. Therefore, the aim of this study was to evaluate the effects of 2 modes of long-term physical training on HD patients' physical fitness, perception of health and overall life situation. PATIENTS AND METHODS: Forty-eight HD patients, free of any other systemic disease, who followed 2 modes of exercise training for 4 years, were studied. Half of them (group A) were randomly assigned to participate in a supervised outpatient exercise training program (3/weekly) on the non-dialysis days, while the other half (group B) followed a training program with stationary bicycles during their HD sessions (3/weekly). The measured domains of physical fitness and well-being every year were: aerobic capacity, as estimated from a modified Bruce treadmill exercise test and spiroergometric study, the patients' perception of health, the overall life situation and the employment status. RESULTS: During the 4-year study, there were 8 drop-outs in group A and 5 in B. No adverse effects of the exercise programs were reported. The 1 year of exercise training resulted in 38% in group A (16 patients, who remained in the study) and 31% in group B (18 patients) improvement of exercise time, and a 47% increase in group A of peak oxygen consumption (VO2peak) and a 36% in group B in comparison to baseline value. After 3 additional years of training, significant improvements were also noted in exercise time (by 53% in group A and by 43% in B) and VO2peak (by 70% in group A and by 50% in group B), as well as in other gas exchange variables in comparison to baseline values. However, the improvements in group A were more pronounced than in B. Interestingly, the gains in exercise capacity were more enhanced in the first year of training in both groups. After 4-year training, significantly more patients in both groups perceived their health and overall life situation as well, compared to baseline. In addition, perception of improved health was higher in group A. The increase in the proportion of patients working was also higher in group A than B after the 4-year training. CONCLUSION: HD patients can adhere to long-term physical training programs on the non-dialysis days, as well as during hemodialysis with considerable improvements in physical fitness and health. Although training out of HD seems to result in better outcomes, the drop out rate was higher.

Adult↗
PubMed2004

Cardiac adaptations following exercise training in hemodialysis patients.

Patients with chronic renal failure (CRF) on hemodialysis (HD) are at increased risk of cardiovascular disease. This is due, mainly, to a higher prevalence of established arteriosclerotic risk factors, including diabetes mellitus, hypertension, dyslipidemia, physical inactivity, as well as to unique CRF-related risk factors. Accordingly, cardiorespiratory insufficiency, left ventricle dysfunction, atherosclerosis and cardiac sympathetic overestimation may often antedate, and hence contribute to exercise intolerance and to increased morbidity and mortality. In HD patients the application of exercise training programs is effective in improving cardiorespiratory capacity, as demonstrated mainly by the increasing of VO2peak. Moreover, better left ventricular systolic function at rest, as well as at effort following training was suggested. Indeed, the increase of cardiac vagal outflow and the decrease of sympathetic over-activity at rest are significantly beneficial results of exercise training in HD patients. However, whether these outcomes reduce the incidence of cardiac morbidity and mortality rate remains to be determined.

Adaptation, Physiological↗
PubMed2004

Exercise rehabilitation and skeletal muscle benefits in hemodialysis patients.

End-stage renal disease patients on hemodialysis (HD) are characterized by poor exercise tolerance and debilitation symptoms, despite advances in dialysis procedures and erythropoietin use. Specifically, the muscle strength and endurance are diminished, as result of skeletal muscle dysfunction and atrophy. These changes are presumed to be secondary to uremic toxins, anemia, malnutrition, deconditioning, neurohormonal insults and other disorders. Previous studies have shown that exercise training limits the pathophysiological changes that occur in HD patients, mainly regarding peripheral skeletal muscle. It is supported that significant peripheral adaptations to training occur, as evidenced by the improvement of muscle function. Especially, morphological and metabolic benefits in the skeletal muscles have been well-documented in HD patients following physical rehabilitation programs. Such beneficial adaptations increase endurance and muscle strength and contribute to improved work capacity. The better understanding of these adaptive mechanisms may allow for improved exercise training strategies in these patients.

Exercise↗
PubMed2002

Effects of athletic training on heart rate variability triangular index.

The purpose of this study was to assess the heart rate variability triangular index (HRVI) in elite track and field athletes. Sixty healthy males (mean aged 22.1 +/- 3.5 years) -15 long distance runners (group A), 15 speed runners (Group B), 15 throwers (Group C) and 15 non-trained subjects (Group D) were submitted to spiroergometric test, m-mode echocardiography and 24-h ambulatory ECG monitoring. The HRVI, mean heart rate, mean interval between two consecutive R waves of the QRS complexes (R-R interval) and standard deviation of the R-R (SDRR) were assessed through time domain method on computed 24-h Holter recordings. The HRVI and the SDRR were 62.2 +/- 9.6 and 220 +/- 40 ms correspondingly in group A, 52.7 +/- 6.0 and 210 +/- 40 ms in B, 44.5 +/- 5.3 and 180 +/- 40 ms in C, 39.3 +/- 6.4 and 180 +/- 30 ms in D. The HRVI and the mean R-R were found to differ statistically between groups A, B and C versus D (P < 0.05). However, the higher value in HRVI was found in group A. Maximal oxygen consumption (VO2max) was 62.0 +/- 4.4 ml kg-1 min-1 in group A, 52.7 +/- 6.0 in group B, 44.6 +/- 5.3 in C and 41.6 +/- 6.0 in D. The higher value in VO2max was also found in group A. The left ventricular mass index (LVMI) and end-diastolic volume index (EDVI) were 136 g m-2 and 83 ml m-2 correspondingly in group A, 136 and 79 in B, 124 and 56 in C and 88 and 55 in group D. The HRVI was found to have a significant relationship with VO2max and EDVI only in group A. On the other hand, no significant relationships were found between HRVI and LVMI in all groups. It is concluded, that the enhanced HRVI in athletes is affected by exercise training pattern. Moreover, HRVI depends on the level of VO2max in endurance-trained, but is independent from the extent of myocardial hypertrophy in all types of training.

Adult↗
PubMed2001

A decrease in soleus muscle force generation in rats after downhill running.

The purpose of the present study was to investigate the immediate and 48-hr post-exercise effects of eccentric contraction-biased exercise on the contractile properties of the soleus muscle in situ. Adult male Wistar rats were categorised into sedentary control rats (n = 10), rats studied immediately (n = 10), and rats studied 48 hours after the exercise (n = 10). The exercise protocol consisted of a 90-min intermittent downhill running (-16 degrees, 16 m/min) on a motor-driven treadmill. The contractile properties of the soleus muscle were recorded following i.p. chloral hydrate anaesthesia. Isometric twitch force (Pt), time-to-peak tension (TPT), half-relaxation time (1/2 RT), and tetanic force at stimulation frequencies of 40, 80, and 100 Hz were recorded. A low-frequency muscle fatigue protocol (stimulation at 4 Hz for 5 min) was applied to test for fatigability. The main findings indicated that Pt generation dropped both immediately and 48 hr after the exercise, while tetanic force was partially restored after 48 hr. Exercise-induced E-C coupling failure and contractile machinery disorganisation due to muscle injury are put forward as the main force reduction causes.

Analysis of Variance↗
PubMed1999

Cardiac effects of exercise rehabilitation in hemodialysis patients.

Exercise training has well documented beneficial effects in a variety of cardiac disorders. End stage renal disease patients present many cardiovascular complications and suffer from impaired exercise capacity. No study to date has adequately examined the cardiac responses to exercise training in renal patients on hemodialysis (HD). To determine the effects of an exercise rehabilitation program on the left ventricular function at rest and during submaximal effort, 38 end-stage renal disease patients on maintenance HD were randomised into three groups. Sixteen of them (group A--mean age 46.4+/-13.9 years), without clinical features of heart failure, participated in a 6-month supervised exercise renal rehabilitation program consisting of three weekly sessions of aerobic training, 10 (group B--mean age 51.4+/-12.5 years) followed a moderate exercise program at home, and the other 12 (group C--mean age 50.2+/-7.9 years) were not trained and remained as controls. The level of anemia and the HD prescription remained constant during the study. Fifteen sex- and age-matched sedentary individuals (group D--mean age 46.9+/-6.4 years) were the healthy controls. All subjects at the start and end of the program underwent physical examination, laboratory tests, treadmill exercise testing, M-mode and 2-D echocardiograms performed at rest and at peak of supine bicycle exercise. Left ventricular volumes (EDV, ESV) and mass (LVM) were measured and ejection fraction (EF), stroke volume index (SVI) and cardiac output index (COI) were calculated by standard formulae. The maximal oxygen consumption increased by 43% (P<0.001) and the exercise time by 33% (P<0.001) after training in group A, by 17% (P<0.001) and 14% (P<0.01), respectively, in B, and both remained unchanged in group C. Training in group A was also associated with an increase in LVIDd (from 52.1+/-6.4 to 54.0+/-6.1 mm, P<0.001) and LVM (226+/-67 to 240+/-84 g, P<0.05) at rest with no change noted in groups B and C. Following a 6-month exercise training in group A an increase was also found in the resting EF by 5% (P<0.01) and SVI by 14% (P<0.001). There was no change found in groups B and C. Supine bicycle exercise after training in group A was associated with an improvement in EF by 14% compared to the pre-training change (P<0.001), SVI by 14% (P<0.001) and COI by 73% (P<0.001). These changes from rest to submaximal exercise were less pronounced in group B following training at home. The untrained patients demonstrated no changes in LV systolic function over the 6-month period. These results demonstrate that intense exercise training improves LV systolic function at rest in HD patients; both intense and moderate physical training leads to enhanced cardiac performance during supine submaximal exercise.

Adult↗
PubMed1999

Effects of physical training on heart rate variability in patients on hemodialysis.

Dysfunction of the cardiac autonomic nervous system is a known complication of end-stage renal disease. The objective of the study was to mainly investigate the effects of physical training on 24-hour vagal cardiac activity in dialysis patients. Sixty chronic uremic patients (mean age 48 +/- 12 years) on maintenance hemodialysis were studied. After initial evaluation, 30 patients (group A) were randomly assigned to a 6-month exercise training program (3/week). The other 30 patients (group B) and 30 nonuremic sedentary persons (group C) remained untrained and were used as controls. Parasympathetic activity was assessed at the beginning and the end of the study noninvasively from 24-hour electrocardiographic ambulatory monitoring by calculating heart rate variability (HRV). HRV index, mean NN interval, and standard deviation NN (SDNN) were measured according to the "triangular method." At baseline HRV index, mean RR, SDNN, and aerobic capacity were significantly reduced in both hemodialysis groups compared with values in group C. Also, 40% of all patients on hemodialysis and 16% of group C had arrhythmias (Lown class >II). Moreover, hemodialysis patients with a more depressed HRV index (<25, n = 37) had a higher incidence of arrhythmias (60%) compared to those with HRV index >25 (p <0.05). Exercise training in group A significantly increased HRV index from 22 +/- 7 to 28 +/- 9 (p <0.05) and SDNN from 0.11 +/- 0.03 to 0.13 +/- 0.04 (p <0.05). Furthermore, fewer patients continued to have an HRV index <25 (by 40%) and arrhythmias (by 33%) compared with baseline data. Training was also associated with a significant improvement in fitness level, as assessed by maximal oxygen consumption (by 41%; p <0.05) and exercise testing duration (by 33%; p <0.05). There was a significant correlation in HRV index and maximal oxygen consumption. No changes were observed in the control groups between baseline and follow-up data. Results demonstrate that physical training in hemodialysis patients augments cardiac vagal activity and decreases vulnerability to arrhythmias.

Adult↗
PubMed1999

White coat hypertension detected during screening of male adolescent athletes.

We investigated the utility of the selective use of ambulatory BP monitoring (ABPM) and echocardiography in detecting truly hypertensive adolescents from a cohort of young adolescent athletes undergoing BP screening. A total of 410 athletes (aged 16.4+/-2.6 years) were screened and, if initial BP measurement detected a persistently elevated BP (>140 mm Hg systolic or >90 mm Hg diastolic), ABPM and echocardiography were performed. Eighteen clinically hypertensive cases (4.4%) were detected and evaluated with a 24-h ABPM. Sixteen of them were defined as having "white coat hypertension" because they were detected to have normal daytime and nocturnal BP. An elevated level of BP confirmed on ABPM was recorded in only two (0.5%) athletes. Echocardiography failed to demonstrate significant abnormalities.

Adolescent↗
PubMed1998

The effects of exercise training on muscle atrophy in haemodialysis patients.

BACKGROUND: Patients with end-stage renal disease on haemodialysis (HD) have limited work capacity. Many structural and functional alterations in skeletal muscles contribute to this disability. METHODS: To evaluate the effects of exercise training on uraemic myopathy, seven HD patients (mean age 44.1+/-17.2 years) were studied. Open muscle biopsies were taken from their vastus lateralis muscle before and after a 6-month exercise rehabilitation programme and examined by routine light- and transmission electron-microscopy. Histochemical stainings of frozen sections were performed and morphometric analysis was also applied to estimate the proportion of each fibre type and the muscle fibre area. Spiroergometric and neurophysiological testing and peak extension forces of the lower limbs were measured before and after exercise training. RESULTS: All patients showed impaired exercise capacity, which was associated with marked muscular atrophy (mean area 2548+/-463 microm2) and reduction in muscle strength and nerve conduction velocity. All types of fibres were atrophied, but type II were more affected. The ultrastructural study showed severe degenerative changes in skeletal muscle fibres, mitochondria, and capillaries. Exercise training had an impressive effect on muscular atrophy; in particular the proportion of type II fibres increased by 51% and mean muscle fibre area by 29%. Favourable changes were also seen on the structure and number of capillaries and mitochondria. These results were confirmed by a 48% increase in VO2 peak and a 29% in exercise time, as well as an improvement in the peak muscle strength of the lower limbs and in nerve conduction velocity. CONCLUSIONS: Skeletal muscle atrophy in HD patients contribute to their poor exercise tolerance. The application of an exercise training rehabilitation programme improved muscle atrophy markedly, and therefore had beneficial effects in overall work performance.

Adult↗
PubMed1998

Effect of exercise on the proportion of unsaturated fatty acids in serum of untrained middle aged individuals.

OBJECTIVES: To examine whether prolonged moderate exercising by untrained middle aged individuals of both sexes affects the plasma ratio of unsaturated to saturated (U/S) fatty acids in the non-esterified fatty acid (NEFA) and triacylglycerol (TG) fractions. METHODS: Twenty two healthy untrained volunteers (eleven men and eleven pre-menopausal women), aged 35-55, exercised on bicycles at 50-55% maximal heart rate reserve (estimated 61% maximal oxygen uptake) for one hour. Pre- and post-exercise blood samples were analysed for lactate, glucose, glycerol, individual NEFAs and TG acyl groups, cholesterol, high density lipoprotein cholesterol, urea, cortisol, and testosterone. Biopsy specimens of adipose tissue were analysed for TG acyl group composition. RESULTS: Serum total NEFAs increased significantly whereas total TG decreased significantly in both sexes. Changes in individual fatty acids, in both the NEFA and TG fractions, generally paralleled changes in the total pool but were not proportionate. As a result, U/S NEFAs increased in both sexes, although significantly only in women. The shift was in the direction of the composition of the major source of blood NEFAs--that is, adipose tissue TG. U/S acyl groups of TG also increased in both sexes, although significantly only in men. CONCLUSIONS: Prolonged moderate exercise increases the U/S ratio of serum NEFAs and TG. This may add to the beneficial effects of exercise given the protective role of unsaturated fatty acids against coronary heart disease.

Adult↗
PubMed1997

Exercise renal rehabilitation program: psychosocial effects.

The aim of this study was to assess the psychosocial effects of exercise training on hemodialysis (HD) patients. Thirty-one uremic patients, aged 50.6+/-11.6 years, on maintenance HD were studied. Twenty patients were selected at random for a 6-month exercise renal rehabilitation program (ERRP) consisting of 3 weekly sessions of exercise training. The other 11 patients were assigned to sedentary control status. A formal psychosocial assessment, which included affective (Beck Depression Inventory, BDI), quality of life (Quality of Life Index, QLI) and personality (Eysenck Personality Questionnaire, EPQ) parameters, was performed with validated questionnaires at the beginning and the end of the ERRP. After training significant improvement occurred in physical capacity (VO2max increased from 16.8+/-6.2 to 23.2+/-7.6 ml/kg/min, p < 0.05). Although the level of depression did not differ betwen the 2 groups at pretesting, the ERRP group showed a decrease in their self-report of depression (decrease in BDI score value, from 21.0+/-10.4 to 13.7+/-9.5, p < 0.05) after the training program. From the relationship between the baseline levels of BDI depression and changes in VO2max in the ERRP group it was suggested that the most severely depressed patients got the greatest beneficial effects from exercise training. Moreover, trained patients demonstrated an improvement in QLI (from 6.3+/-1.5 to 9.0+/-0.9, p < 0.05). This improvement was found to be dependent on the participation in ERRP, the effects of the training and the improvement in the depression. All the above functional and psychosocial parameters remained unchanged in the controls. The results demonstrate that ERRP is an effective emotional therapeutic method for HD patients and improves their quality of life.

Adult↗
PubMed1993

Plasma TSH, T3, T4 and cortisol responses to swimming at varying water temperatures.

The acute effect of 30-min swimming at a moderate speed, at three water temperatures (20, 26 and 32 degrees C) on plasma thyroid stimulating hormone (TSH), free thyroxine (F.T4), triiodothyronine (T3) and cortisol concentrations was studied in 15 élite male swimmers. Blood was sampled before and immediately after the events. The heart rate, which was continuously monitored during exercise, had the highest response at 32 degrees C and the lowest at 20 degrees C. Blood lactate concentrations were found to be similar after the three tests. Plasma TSH and F.T4 were found to be significantly increased (by 90.4% and 45.7% respectively) after swimming at 20 degrees C, decreased at 32 degrees C (by 22.3% and 10.1% respectively) and unchanged at 26 degrees C. Exercise at these three water temperatures did not significantly affect T3. Finally, plasma cortisol was found to be increased after swimming at 32 degrees C (by 82.8%) and 26 degrees C (by 46.9%), but decreased at 20 degrees C (by 6.1%).

Adolescent↗
PubMed1993

Effect of water temperature on performance, lactate production and heart rate at swimming of maximal and submaximal intensity.

The effect of water temperature on performance effort, monitored heart rate and lactate production during freestyle swimming at maximal and submaximal speed has been studied. Fifteen male sprint swimmers performing 100 m swimming and fifteen comparable endurance competitors performing 30 min swimming at submaximal speed served as subjects. Water temperature in separate events was 20, 26 and 32 degrees C. At maximal performance there was a direct relationship between any two of the following parameters: water temperature, average swimming speed, heart rate during the competition and plasma lactate concentration after the event. Thus, the best effort (speed 1.704 m/s), the highest peak heart rate (185 beats/min) and the highest lactate level (19.8 mmol/l) were observed at 32 degrees C (all mean values). In contrast, these values were markedly lower at 20 degrees C. At the submaximal effort, water temperature was related to peak heart rate only. The highest peak heart rate (144 beats/min) was again obtained at 32 degrees C, while the lactate concentration (4.2-5.2 mmol/l) was independent of temperature. Water temperature appears to have a direct effect on performance effort, heart rate and lactate production during swimming at maximal intensity, whereas this effect seems to fade at submaximal efforts.

Adolescent↗
PubMed1985

Changes in left ventricular anatomy during haemodialysis, continuous ambulatory peritoneal dialysis and after renal transplantation.

The changes in left ventricular anatomy in 30 patients with end-stage renal disease and stable cardiac function, undergoing regular haemodialysis (10 patients), continuous ambulatory peritoneal dialysis (10 patients) and after successful renal transplantation (10 patients) were evaluated by M-mode echocardiography. Initially all had evidence of left ventricular hypertrophy and dilatation. Reevaluation after a mean follow-up of 22 months on each mode of treatment showed that in the haemodialysis group the left ventricular mass and volume were increased, while in continuous ambulatory peritoneal dialysis (CAPD) and, especially renal transplantation, the hypertrophy and dilatation were reversed. This improvement was probably due to a reduction of cardiac workload.

Adult↗
PubMed1979

Work capacity, contractile protein and quantitative electromyogram (EMG) changes following exercise or nandrolone decanoate treatment in experimentally induced muscle disuse atrophy in rats.

Anabolic steroid administration and planned exercise have been the two main methods applied to improve the function and morphology of atrophied muscle tissue. The effects of these two factors-specifically nandrolone decanoate administration and exercise by swimming on muscle weight, EMG activity, work capacity and on contractile protein content of rat gastrocnemius muscle, following experimentally induced atrophy by immobilization, were investigated. The results appear to support the conclusion that although both types of treatment obtain significant positive results exercise acts more effectively than the anabolic steroid in this respect.

Actomyosin↗