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Results for “Exercise training”

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PubMed1999

Effect of exercise training on heart rate variability in healthy older adults.

OBJECTIVE: To determine the effect of exercise training on cardiac autonomic modulation in normal older adults by using analysis of heart rate variability. SUBJECTS: The exercise group consisted of 7 men and 9 women aged 66 +/- 4 years. The comparison group consisted of 7 men and 9 women also aged 66 +/- 4 years. METHOD: Heart rate variability was determined from 24-hour Holter recordings before and after 12 months of supervised exercise, which consisted of 3 months of stretching and 9 months of 5 hours/week aerobic exercise at approximately 70% of maximal oxygen uptake. Heart rate variability was measured at baseline and 12 months later in the comparison group, who had not changed their usual activity level. RESULTS: In the exercise group maximal oxygen consumption increased from 1.8 +/- 0.5 L/min to 2.2 +/- 0.7 L/min (P <.05). The standard deviation of normal interbeat intervals increased from 126 +/- 21 ms to 142 +/- 25 ms. Mean nighttime heart rate decreased from 67 +/- 6 beats/min to 63 +/- 5 beats/min. Increased fitness level had little effect on indexes of heart rate variability, which reflect parasympathetic or mixed sympathetic/parasympathetic modulation of heart rate. There was no change in heart rate or heart rate variability in the comparison group. CONCLUSIONS: Exercise training increases total heart rate variability in normal older adults. The most marked alterations are in nocturnal heart rate. Heart rate variability is stable over a 1-year period in older adults who do not alter their activity level.

Aged↗

PubMed1988

Exercise training after anterior Q wave myocardial infarction: importance of regional left ventricular function and topography.

To determine whether the extent of left ventricular dysfunction and the degree of shape distortion can predict outcome in survivors of moderate-sized anterior Q wave myocardial infarction who are undergoing exercise training, these variables were measured by two-dimensional echocardiography before and after 12 weeks of a low level exercise training program starting 15 weeks after infarction in 13 patients (7 in group 1 and 6 in group 2) and 12 weeks apart in 24 matched control patients without training. By the end of training, the functional class score had increased in group 2 (from 2.25 to 2.67, p less than 0.005) but had not changed in group 1. Further discrimination of groups 1 and 2 was provided by an initial asynergy (akinesia or dyskinesia, or both) less than 18% or greater than or equal to 18%. Compared with group 1, group 2 had greater initial asynergy (32 versus 6%, p less than 0.001), expansion index (asynergic/normal endocardial segment length: 1.8 versus 1.6, p less than 0.025) and peak shape distortion index (12.2 versus 1.0 mm, p less than 0.005) but lower ejection fraction (43 versus 59%, p less than 0.05) and thinning ratio (asynergic/normal wall thickness: 0.61 versus 0.74, p less than 0.05). These variables did not change with training in group 1. However, in group 2, training caused significant increase in asynergy (from 32 to 40%, p less than 0.05), expansion index (from 1.8 to 2.0, p less than 0.01) and peak shape distortion (from 12.2 to 20.9 mm, p less than 0.05) associated with a decrease in thinning ratio (from 0.61 to 0.51, p less than 0.001) and ejection fraction (from 43 to 30%, p less than 0.005). Initial values for these variables were similar for corresponding control groups but did not change over the 12 weeks. Thus, patients with greater than or equal to 18% left ventricular asynergy on the initial echocardiogram showed more shape distortion, expansion and thinning before exercise training and developed further functional and topographic deterioration with training.

Adult↗

PubMed2001

Physiological demands of top-class soccer refereeing in relation to physical capacity: effect of intense intermittent exercise training.

To examine the activity profile and physiological demands of top-class soccer refereeing, we performed computerized time-motion analyses and measured the heart rate and blood lactate concentration of 27 referees during 43 competitive matches in the two top Danish leagues. To relate match performance to physical capacity and training, several physiological tests were performed before and after intermittent exercise training. Total distance covered was 10.07+/-0.13 km (mean +/- s(x)), of which 1.67+/-0.08 km was high-intensity running. High-intensity running and backwards running decreased (P < 0.05) in the second half. Mean heart rate was 162+/-2 beats min(-1) (85+/-1% of maximal heart rate) and the mean blood lactate concentration was 4.9+/-0.3 (range 1.7-14.0) mmol x l(-1). The amount of high-intensity running during a match was related to the Yo-Yo intermittent recovery test (r2 = 0.57; P<0.05) and the 12 min run (r2 = 0.21; P<0.05). After intermittent training (n = 8), distance covered during high-intensity running was greater (2.06+/-0.13 vs 1.69+/-0.08 km; P< 0.05) and mean heart rate was lower (159+/-1 vs 164+/-2 beats x min(-1); P< 0.05) than before training. The results of the present study demonstrate that: (1) top-class soccer referees have significant aerobic energy expenditure throughout a game and episodes of considerable anaerobic energy turnover; (2) the ability to perform high-intensity running is reduced towards the end of matches; (3) the Yo-Yo intermittent recovery test can be used to evaluate referees' match performance; and (4) intense intermittent exercise training improves referees' performance capacity during a game.

Exercise↗

PubMed2003

Effects of exercise training and hormone replacement therapy on lean and fat mass in postmenopausal women.

BACKGROUND: Menopause is associated with decreases in lean mass and increases in fat mass. Serum hormone levels and hormone replacement therapy (HRT) may modify the effects of exercise training on body composition in postmenopausal women. METHODS: We assessed the changes in total body and regional lean soft tissue and fat mass (using dual-energy x-ray absorptiometry) in 94 sedentary postmenopausal women, aged 40-65 years, after 12 months of resistance and weight-bearing aerobic exercise training. Women currently on oral HRT (n = 39) and not on HRT (n = 55) were randomized within groups to exercise and no exercise, resulting in four groups: exercise + HRT (n = 20), HRT (n = 22), exercise (n = 24), and control (n = 28). Fasting blood samples were measured for resting serum total levels of estrone, estradiol, cortisol, androstenedione, growth hormone, and insulin-like growth factor 1 at baseline and 12 months. RESULTS: We found significant effects of exercise on increases in total body, arm, and leg lean soft tissue mass, and decreases in leg fat mass and percentage of body fat. There were no interaction effects of exercise and HRT on the changes in muscle strength and body composition. No significant changes in total hormone levels were found after 12 months. CONCLUSIONS: Exercise training resulted in significant beneficial changes in lean soft tissue and fat mass in early postmenopausal women. These changes in body composition were neither influenced by prolonged HRT use nor accompanied by changes in total levels of the hormones determined in this study.

Adipose Tissue↗

PubMed2001

Change in post-exercise vagal reactivation with exercise training and detraining in young men.

We studied the effects of aerobic exercise training and detraining in humans on post-exercise vagal reactivation. Ten healthy untrained men trained for 8 weeks using a cycle ergometer [70% of initial maximal oxygen uptake (VO2max) for 1 h, 3-4 days.week-1] and then did not exercise for the next 4 weeks. Post-exercise vagal reactivation was evaluated as the time constant of the beat-by-beat decrease in heart rate during the 30 s (t30) immediately following 4 min exercise at 80% of ventilatory threshold (VT). The VO2max and the oxygen uptake at VT had significantly increased after the 8 weeks training programme (P < 0.0001, P < 0.001, respectively). The t30 had shortened after training, and values after 4 weeks and 8 weeks of training were significantly shorter than the initial t30 (P < 0.05, P < 0.01, respectively). The change in the t30 after 8 weeks of training closely and inversely correlated with the initial t30 (r = -0.965, P < 0.0001). The reduced t30 was prolonged significantly after 2 weeks of detraining, and had returned almost to the baseline level after a further 2 weeks of detraining. These results suggest that aerobic exercise training of moderate intensity accelerates post-exercise vagal reactivation, but that the accelerated function regresses within a few weeks of detraining.

Adult↗

PubMed1994

Isokinetic strength and endurance during 30-day 6 degrees head-down bed rest with isotonic and isokinetic exercise training.

The purpose of our study was to determine if an intensive, intermittent, isokinetic, lower extremity exercise training program would attenuate or eliminate the decrease of muscular strength and endurance during prolonged bed rest (BR). The 19 male subjects (36 +/- 1 yr, 178 +/- 2 cm, 76.5 +/- 1.7 kg) were allocated into a no exercise (NOE) training group (N = 5), an isotonic (lower extremity cycle ergometer) exercise (ITE) training group (N = 7), and an isokinetic (isokinetic knee flexion-extension) exercise (IKE) training group (N = 7). Peak knee (flexion and extension) and shoulder (abduction-adduction) functions were measured weekly in all groups with one 5-repetition set. After BR, average knee extension total work decreased by 16% with NOE, increased by 27% with IKE, and was unchanged with ITE. Average knee flexion total work and peak torque (strength) responses were unchanged in all groups. Force production increased by 20% with IKE and was unchanged with NOE and ITE. Shoulder total work was unchanged in all groups, while gross average peak torque increased by 27% with ITE and by 22% with IKE, and was unchanged with NOE. Thus, while ITE training can maintain some isokinetic functions during BR, maximal intermittent IKE training can increase other functions above pre-BR control levels.

Adult↗

PubMed2005

Impaired exercise capacity and exercise training in maintenance hemodialysis patients.

Patients with advanced chronic renal failure, including those undergoing maintenance hemodialysis (MHD), commonly suffer from sarcopenia and reduced physical exercise capacity. The causes of these disorders include anemia, cardiovascular and pulmonary diseases, other comorbid conditions, altered skeletal muscle metabolism, myopathic changes that are associated with chronic renal failure per se, malnutrition, and physical deconditioning. Exercise training has been shown to increase exercise capacity and, in some studies, to increase muscle mass. In our experience, cardiopulmonary fitness training of sedentary MHD patients for an average of 8.6 weeks using a stationary ergometer increased endurance capacity, physical performance, and physical strength in the lower extremities, and in particular, quadriceps strength, power, and fatigability. This surprising finding of increased lower-extremity strength with cardiovascular fitness training may reflect the possibility that the MHD patients were so deconditioned that the small amount of resistance encountered with pedaling a stationary ergometer increased their physical strength. By the end of the endurance exercise training program, the MHD patients also showed changes in the right vastus lateralis muscle for the mRNA levels of a number of proteins involved with skeletal muscle protein synthesis and hypertrophy. The mRNA levels changed in a direction that would be expected to promote protein accrual and hypertrophy of skeletal muscle. These findings indicate that in sedentary MHD patients endurance exercise training for a few weeks can result in improved exercise capacity and a pattern of transcriptional factors that may promote an increase in skeletal muscle mass.

Anemia↗

PubMedDate not supplied

Heart rate at the estimated lactate threshold in patients with chronic obstructive pulmonary disease: effects on the target intensity for dynamic exercise training.

BACKGROUND: Physical training at the range of exercise intensities associated with sustained blood lactate accumulation seems to rapidly improve aerobic performance in both healthy subjects and patients with chronic obstructive pulmonary disease (COPD). However, it is still unclear whether patients' heart rate (HR) at the estimated lactate threshold (HR [symbol: see text]L)--as expressed in percent attained peak HR (AHR), predicted peak HR (PHR) and HR reserve (HRR)--are comparable with the ranges of intensity that are commonly used for target exercise training in control subjects. METHODS: The authors evaluated 26 patients with stable COPD (forced expiratory volume in 1 second = 1.17 +/- 0.28 L) who were submitted for spirometric evaluation, and, after familiarization, to a symptom-limited ramp-incremental cardiopulmonary exercise testing on a cycle ergometer. RESULTS: The authors were able to identify [symbol: see text]L in only 18 patients (69%). The HR [symbol: see text]L corresponded to wide range of exercise intensities according to the three methods (ranging from 70-95% AHR, 50-90% PHR, and 35-60% HRR). However, most of the subjects would be trained within +/- 5% HR [symbol: see text]L if they had been exercised at 80 to 85% AHR and 40 to 45% HRR; these values correspond to higher (AHR) and lower (HRR) intensities than usually recommended for healthy subjects. CONCLUSIONS: Considering that [symbol: see text]L was not identified in approximately one third of the patients and there was ample variability on HR [symbol: see text]L as %AHR, %PHR, and %HRR, the use of HR and [symbol: see text]L targets for routine exercise prescription does not seem to be clinically justifiable in patients with COPD submitted to pulmonary rehabilitation.

Aged↗

PubMed2005

Effects of endurance exercise-training on single-fiber contractile properties of insulin-treated streptozotocin-induced diabetic rats.

The purpose of this study was to characterize the contractile properties of individual skinned muscle fibers from insulin-treated streptozotocin-induced diabetic rats after an endurance exercise training program. We hypothesized that single-fiber contractile function would decrease in the diabetic sedentary rats and that endurance exercise would preserve the function. In the study, 28 rats were assigned to either a nondiabetic sedentary, a nondiabetic exercise, a diabetic sedentary, or a diabetic exercise group. Rats in the diabetic groups received subcutaneous intermediate-lasting insulin daily. The exercise-trained rats ran on a treadmill at a moderate intensity for 60 min, five times per week. After 12 wk, the extensor digitorum longus and soleus muscles were dissected. Single-fiber diameter, Ca(2+)-activated peak force, specific tension, activation threshold, and pCa(50) as well as the myosin heavy chain isoform expression (MHC) were determined. We found that in MHC type II fibers from extensor digitorum longus muscle, diameters were significantly smaller from diabetic sedentary rats compared with nondiabetic sedentary rats (P < 0.001). Among the nondiabetic rats, fiber diameters were smaller with exercise (P = 0.038). The absolute force-generating capacity of single fibers was lower in muscles from diabetic rats. There was greater specific tension (force normalized to cross-sectional area) by fibers from the rats that followed an endurance exercise program compared with sedentary. From the results, we conclude that alterations in the properties of contractile proteins are not implicated in the decrease in strength associated with diabetes and that endurance-exercise training does not prevent or increase muscle weakness in diabetic rats.

Adaptation, Physiological↗

PubMed1990

Effect of body weight gain on insulin sensitivity after retirement from exercise training.

The objectives of this study were to determine how long increased insulin sensitivity, elicited by exercise training, persists after the end of training and what the effect of weight gain is on this retention. Exercise-trained (ET) rats ran voluntarily in freely rotating wheel cages, and insulin sensitivity was assessed by oral glucose tolerance tests (OGTT) and insulin suppression tests (IST). After training, ET rats were retired for 1, 3, or 7 days (R1, R3, or R7). Initial OGTT and IST studies indicated that sensitivity to insulin-induced glucose uptake was increased in ET rats compared with sedentary control (C) rats and was progressively lost with retirement: ET greater than R1 and R3 greater than R7 and C rats, and this reaction was generally associated with a rapid gain in body weight. Subsequent IST tests were performed on C and R7 rats fed laboratory chow or a hypocaloric diet consisting of equal parts of cellulose and chow for 7 days before the test. The results of these tests showed that steady-state serum glucose (SSSG) levels averaged 165 +/- 12 mg/dl for chow-fed C rats and 172 +/- 11 mg/dl for chow-fed R7 rats that gained body weight at rates twice those of C rats. Chow-fed R7 rats, gaining weight at rates comparable to C rats, had SSSG levels of 104 +/- 6 mg/dl. C and R7 rats fed the hypocaloric diet had SSSG values of 102 +/- 6 and 59 +/- 4 mg/dl, respectively. Muscle glycogen levels were comparable in all groups, and liver glycogen was lower in C and R7 rats fed the hypocaloric diet.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1990

Interactions of iron deficiency and exercise training relative to tissue norepinephrine turnover, triiodothyronine production and metabolic rate in rats.

The interactions of iron deficiency and exercise training relative to resting metabolic rate (RMR), tissue norepinephrine (NE) turnover and triiodothyronine (T3) production were examined in male Sprague-Dawley rats. Animals were assigned to iron-deficient (ID) or control (CN) diets and to sedentary (SD) or treadmill-exercise (EX) groups for 6 or 12 wk. Iron-deficient animals (hemoglobin 7.2 +/- 0.2 g 100 mL-1) had a 17% higher RMR and had slower growth rates than CN animals. Exercise training affected growth but not RMR in iron deficiency. Oxygen consumption (Vo2) following pharmacologic injection of norepinephrine was similar in both iron-deficient and exercised groups despite a 35% lower maximal exercise Vo2 in trained iron-deficient rats. NE turnover was lower in heart (55%) and liver (80%) of iron-deficient animals relative to controls. Trained iron-deficient animals had lower NE turnover in interscapular brown adipose tissue (IBAT) than sedentary iron-deficient animals; however, training did not alter NE turnover in control animals. In vitro liver and IBAT T3 production was similar in all groups except for lower activities (40%) in 6-wk iron-deficient, exercised animals. The significant effect of exercise on the growth attenuation of iron-deficient, exercised animals is thus not explained by increased IBAT metabolic activity or a generalized sympathetic nervous system activation. Decreased T3 production during periods of rapid growth and lean body mass development, however, may be important in exercised, iron-deficient animals.

Adipose Tissue, Brown↗

PubMed1999

[The efficacy and practice of exercise training in patients with chronic obstructive pulmonary disease (COPD)].

Exertional dyspnea is a most popular symptom in COPD patients often lead to exercise intolerance. Indeed the reduced activity in patient's daily life due to dyspnea may lead to deconditioning and peripheral muscle weakness. Bronchodilators and anti-inflammatory drugs are an important treatment to reduce symptoms and improve airflow limitation but not improve deconditioning. Impairment of exercise tolerance is a common problem in patients with COPD and therefore exercise training is an important component of all pulmonary rehabilitation programs. It is now clearly established that exercise training reduce dyspnea, improve exercise tolerance and improve activities of daily living (ADL) and health related quality of life (QOL). Oxygen therapy during exercise are often considered in the COPD patients with exercise induced hypoxemia.

Activities of Daily Living↗

PubMedDate not supplied

[Effect of physical exercise training on the arterial pressure in normotensive subjects].

To determine the effect of exercise training on blood pressure at rest and during maximal exercise 15 adolescent and 15 adult normotensive cyclists were studied after a period of detraining and of physical activity. In the lying position resting blood pressure did not change with training, while a slight but significant decrease in blood pressure (p less than 0.05) was observed on standing up. At the same absolute work rate, after training exertional blood pressure was lower than before training, but at peak exercise the same blood pressure levels were achieved before and after training. These results indicate that, contrary to what has been reported in the sedentary subject, resuming exercise training after a period of detraining brings about in the normotensive athlete only minor changes in blood pressure.

Adolescent↗

PubMed1997

Effects of aerobic exercise training and yoga on the baroreflex in healthy elderly persons.

It is unclear whether the age-associated reduction in baroreflex sensitivity is modifiable by exercise training. The effects of aerobic exercise training and yoga, a non-aerobic control intervention, on the baroreflex of elderly persons was determined. Baroreflex sensitivity was quantified by the alpha-index, at high frequency (HF; 0.15-0.35 Hz, reflecting parasympathetic activity) and mid-frequency (MF; 0.05-0.15 Hz, reflecting sympathetic activity as well), derived from spectral and cross-spectral analysis of spontaneous fluctuations in heart rate and blood pressure. Twenty-six (10 women) sedentary, healthy, normotensive elderly (mean 68 years, range 62-81 years) subjects were studied. Fourteen (4 women) of the sedentary elderly subjects completed 6 weeks of aerobic training, while the other 12 (6 women) subjects completed 6 weeks of yoga. Heart rate decreased following yoga (69 +/- 8 vs. 61 +/- 7 min-1, P < 0.05) but not aerobic training (66 +/- 8 vs. 63 +/- 9 min-1, P = 0.29). VO2 max increased by 11% following yoga (P < 0.01) and by 24% following aerobic training (P < 0.01). No significant change in alpha MF (6.5 +/- 3.5 vs. 6.2 +/- 3.0 ms mmHg-1, P = 0.69) or alpha HF (8.5 +/- 4.7 vs. 8.9 +/- 3.5 ms mmHg-1, P = 0.65) occurred after aerobic training. Following yoga, alpha HF (8.0 +/- 3.6 vs. 11.5 +/- 5.2 ms mmHg-1, P < 0.01) but not alpha MF (6.5 +/- 3.0 vs. 7.6 +/- 2.8 ms mmHg-1, P = 0.29) increased. Short-duration aerobic training does not modify the alpha-index at alpha MF or alpha HF in healthy normotensive elderly subjects. alpha HF but not alpha MF increased following yoga, suggesting that these parameters are measuring distinct aspects of the baroreflex that are separately modifiable.

Aged↗

PubMed1998

Exercise training in patients with CHF and heart transplant recipients.

The number of chronic heart failure (CHF) patients and heart transplantation (HT) recipients enrolled in rehabilitation and maintenance exercise programs continues to expand. There is growing clinical consensus that stable patients with CHF respond favorably to exercise training and convincing evidence that exercise training should be an essential adjunct therapy in postoperative management of HT recipients. This review examines the following specific advances in exercise physiology for heart failure and heart transplantation patients: 1) the mechanisms of exercise intolerance in CHF and the results of exercise rehabilitation studies in these patients; 2) the exercise challenges conferred by glucocorticoid therapy and chronic cardiac denervation in HT recipients; and 3) a summary of current recommendations and guidelines for exercise prescription in each patient population.

Exercise Therapy↗

PubMed2002

[The effects of exercise training on plasma tumor necrosis factor-alpha, blood leucocyte and its components in congestive heart failure patients].

OBJECTIVE: To evaluate six-minute walking test (6-MWT) in treatment of CHF and to investigate the effect of exercise training on blood leucocyte and its components and plasma TNF alpha in CHF patients. METHODS: 60 cases with NYHA II-III CHF patients underwent 6-MWT within 24 hours after hospitalization. The walking distance, heartbeat, plasma TNF alpha, and blood leucocyte and its components were investigated before and after walking test. These patients were then randomized into two groups, a training group (32 cases) and a control group (28 cases). Besides routine medication, 6-MWT was performed in the training group twice a day for 8 weeks. The same parameters were redetermined after 8 weeks of follow-up. 23 cases with NYHA IV CHF patients were investigated with the same parameters in the first day after hospitalization. RESULTS: Blood leucocyte count and percentage of granulocytes and mononuclears in cases with NYHA III-IV were significantly higher than those with NYHA II. There were significant reduction of heartbeat and prolongation of walking distance in CHF patients after exercise training. Blood leucocyte count and the percentage of granulocytes and mononuclear and plasma TNFalpha level were reduced more in the training group than the control group after 8 weeks the treatment. CONCLUSIONS: There is significantly higher leucocyte count and percentage of granulocytes and mononuclears in CHF with NYHA III-IV than those with NYHA II. 6-MWT, as an exercise training, is simple, safe, and not harmful. It can not only evaluate the severity of CHF but also serve as a therapeutic measure for CHF. Moreover the excessive activation of cytokines as TNFalpha could be reduced by 6-MWT training in CHF patients.

Adult↗

PubMed2005

Effects of endurance exercise training on heart rate variability and susceptibility to sudden cardiac death: protection is not due to enhanced cardiac vagal regulation.

Low heart rate variability (HRV) is associated with an increased susceptibility to ventricular fibrillation (VF). Exercise training can increase HRV (an index of cardiac vagal regulation) and could, thereby, decrease the risk for VF. To test this hypothesis, a 2-min coronary occlusion was made during the last min of a 18-min submaximal exercise test in dogs with healed myocardial infarctions; 20 had VF (susceptible), and 13 did not (resistant). The dogs then received either a 10-wk exercise program (susceptible, n=9; resistant, n=8) or an equivalent sedentary period (susceptible, n=11; resistant, n=5). HRV was evaluated at rest, during exercise, and during a 2-min occlusion at rest and before and after the 10-wk period. Pretraining, the occlusion provoked significantly (P<0.01) greater increases in HR (susceptible, 54.9+/-8.3 vs. resistant, 25.0+/-6.1 beats/min) and greater reductions in HRV (susceptible, -6.3+/-0.3 vs. resistant, -2.8+/-0.8 ln ms2) in the susceptible dogs compared with the resistant animals. Similar response differences between susceptible and resistant dogs were noted during submaximal exercise. Training significantly reduced the HR and HRV responses to the occlusion (HR, 17.9+/-11.5 beats/min; HRV, -1.2+/-0.8, ln ms2) in the susceptible dogs; similar response reductions were noted during exercise. In contrast, these variables were not altered in the sedentary susceptible dogs. Posttraining, VF could no longer be induced in the susceptible dogs, whereas four sedentary susceptible dogs died during the 10-wk control period, and the remaining seven animals still had VF when tested. Atropine decreased HRV but only induced VF in one of eight trained susceptible dogs. Thus exercise training increased cardiac vagal activity, which was not solely responsible for the training-induced VF protection.

Animals↗

PubMed1986

Myocardial perfusion changes following 1 year of exercise training assessed by thallium-201 circumferential count profiles.

The effect of exercise training on myocardial perfusion was assessed using initial and 1-year thallium-201 (Tl-201) exercise studies in 56 patients with stable coronary artery disease (CAD). Subjects had been randomized into a trained group participating in supervised exercise three times per week and a control group. Indices (non-dimensional units) based on computer-analyzed circumferential count profile from nine regions of the heart, assessed in three projections, were used to eliminate observer bias and more accurately quantitate Tl-201 distribution and 4-hour washout. There was serial improvement of the global distribution count profiles in 21 of 27 (77.8%) of the trained and in 9 of 29 (31.0%) of the control subjects (p less than 0.001). The mean interval change in global initial distribution over the year period was 5 +/- 13 (mean +/- SD) in the trained and -6 +/- 14 in the control groups (p less than 0.003). The mean initial distribution of the trained group had improvement in all nine regions (significant in three), while the control group showed mean improvement in only one of nine regions. Additionally, the trained group showed improvement in the mean washout in five of nine regions (significant in three), while no mean regional washout improvement occurred in the control group. Thus, in this group of patients with stable CAD, exercise training resulted in apparently improved cardiac perfusion evidenced by enhance Tl-201 uptake and washout.

Coronary Circulation↗