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PubMed1997

Cardiorespiratory response to exercise in patients with exercise-induced bronchial obstruction.

OBJECTIVE: To document the characteristics of the ventilatory response to exercise in patients with exercise-induced bronchial obstruction (EIB). EXPERIMENTAL DESIGN: Comparative study during the period between December 1993 and March 1994. SETTING: Ambulatory care in Ohgaki Municipal Hospital. SUBJECTS AND METHOD: We evaluated 11 children with EIB. Each subject under went symptom-limited cardiopulmonary treadmill exercise testing (Bruce protocol). RESULTS: Patients with EIB showed a significantly lower peak oxygen consumption (peak VO2) than the control subjects. Three patients with EIB developed relative hypoventilation during incremental exercise: an increase in end-tidal carbon dioxide partial pressure (PETCO2) and a decrease in VE/VCO2 were observed at the end-stage of exercise testing. CONCLUSIONS: These findings demonstrate that some patients with EIB develop bronchoconstriction during exercise.

Adolescent↗

PubMed1998

Blood lactate concentrations during exercise: effect of sampling site and exercise mode.

BACKGROUND: The purpose of the study was to compare blood lactate concentrations determined in blood sampled from three sites (finger capillary, ear-lobe capillary, and forearm vein) during exercise on three different ergometers (a cycle ergometer, a treadmill and an arm-crank ergometer). METHODS: A total of 312 well-trained subjects performed either a six-minute steady-state exercise (n = 219) or an incremental exercise test until exhaustion (n = 93). Blood was sampled from two sites after each exercise test and at the end of each stage of the incremental protocol, 852 pairs of blood samples were analysed. RESULTS: Results showed that, when exercise was performed on a cycle ergometer or a treadmill, no significant differences between venous and ear capillary samples were observed whereas finger capillary values were higher. On an arm-crank ergometer, venous and finger capillary lactate concentrations were usually higher than ear capillary values with some discrepancies depending on the times of sampling. CONCLUSIONS: We conclude that lactate values may differ depending on the sampling site and the type of exercise mode. An ear capillary sample may be preferred because it is less affected by lactate release in the arms and easier to obtain.

Adolescent↗

PubMed1999

Decongestant effects on hemodynamics at rest, exercise, and recovery from exercise during--6 degrees of head down tilt.

HYPOTHESIS: Ten males were studied to examine the effects of a decongestant, pseudoephedrine hydrochloride, on rest, exercise, and recovery from exercise during -6 degrees of head down tilt (HDT). METHODS: Subjects were positioned in the HDT for a total of 6 hr: 2 hr 45 min rest, 30 min exercise, and 2 hr 45 min recovery. Sessions were identical except for the ingestion of a drug or placebo. Variables evaluated during rest, exercise, and recovery conditions were: systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR), stroke volume (SV), cardiac output (Q), pulse pressure (PP), mean arterial pressure (MAP), total peripheral resistance (TPR), and forearm blood flow (FBF). RESULTS: During rest PP at 120 min was less than resting baseline, and MAP increased throughout rest. There was a treatment effect for SBP which increased up to 90 min from resting baseline for the placebo treatment only. Normal changes were found with exercise, with all variables increasing above baseline except for TPR which decreased. DBP showed no change during exercise. During the recovery condition for the drug treatment HR decreased, while SBP increased from 30 min. In addition, DBP and MAP were higher for the placebo at 30 min and higher for the drug at 90 min. CONCLUSION: The results show that ingestion of the sympathomimetic agent pseudoephedrine hydrochloride has no significant effects on the cardiovascular system during simulated microgravity.

Adult↗

PubMed2003

Exercise-related goals and self-efficacy as correlates of aquatic exercise in individuals with arthritis.

OBJECTIVE: To examine whether aquatic exercise-related goals, task self-efficacy, and scheduling self-efficacy are predictive of aquatic exercise attendance in individuals with arthritis. A secondary objective was to determine whether high attendees differed from low attendees on goals and self-efficacy. METHODS: The sample comprised 216 adults with arthritis (mean age 69.21 years). Measures included exercise-related goal difficulty and specificity, task and scheduling self-efficacy, and 8-week aquatic exercise attendance. RESULTS: Results of a multiple hierarchical regression analysis were significant (P < 0.01). Goal difficulty, specificity, and task self-efficacy were independent predictors of attendance (P < 0.05). A significant multivariate analysis of variance (P < 0.01) indicated that high attendees had higher task and scheduling self-efficacy and lower goal difficulty than did low attendees (P < 0.05). CONCLUSION: Support for the importance of exercise-related goal setting and self-efficacy was demonstrated. Implications pertain to the design of interventions to impact aquatic exercise.

Absenteeism↗

PubMed1983

Exercise two-dimensional echocardiography: a technique for improving ultrasound images during exercise stress.

A system of exercise stress echocardiography was developed in which, during exercise on a bicycle ergometer in a semirecumbent position, the echocardiographic transducer is held by a special device which maintains a relatively constant position between the transducer and the heart. The system was evaluated in 21 healthy subjects and technically satisfactory studies were obtained in 20. In these, the resolution and relative position of the cardiac image remained stable throughout exercise. Blood pressure and heart rate increased appropriately with our protocol with supine exercise; 95% of the subjects reached 90% of their predicted maximum heart rate for age. Ejection fraction measured by echocardiography increased from 54 +/- 1% to 70 +/- 1%. It is concluded that the use of our transducer-holding device in subjects performing exercise in the supine position significantly improves ultrasonic image quality and should enhance the clinical usefulness of exercise stress echocardiography.

Adult↗

PubMed1985

Mechanism underlying the absence of ischemic changes on the exercise electrocardiogram in patients with abnormal exercise thallium-201 imaging and coronary artery disease.

Patients with coronary artery disease may have reversible abnormalities on a thallium myocardial perfusion study without simultaneous ischemic changes on the exercise electrocardiogram, but the mechanisms responsible for this disparity have not been fully elucidated. A group of 37 patients with angiographically demonstrated coronary artery disease and abnormal thallium perfusion imaging were divided into two groups on the basis of their exercise electrocardiographic ST segment response. Thirteen patients (Group A) had no significant electrocardiographic changes with exercise, while 24 patients (Group B) had ST changes consistent with ischemia during the test. There were no significant differences in clinical or angiographic characteristics between the two groups. Stress test results showed a similar mean duration of exercise in the two groups (6.2 +/- 1.8 versus 6.7 +/- 2.5 min, p = NS), but the patients in Group A achieved a significantly lower mean maximal heart rate (117 +/- 26 versus 132 +/- 21 beats/min, p less than 0.05) and mean maximal double product (19,650 +/- 5116 versus 22,650 +/- 4871, p less than 0.05). There was no consistent pattern of thallium perfusion abnormality noted in Group A to suggest that a particular region of electrically silent myocardium was responsible for ischemia in the absence of electrocardiographic changes. These results suggest that exercise thallium-electrocardiogram discordance is mediated by the level of myocardial workload achieved. An abnormal perfusion scan accompanying an exercise electrocardiogram which does not demonstrate any ischemic ST change may occur when there is sufficient increase in myocardial oxygen demand to result in differential augmentation of myocardial blood flow, but insufficient imbalance of supply and demand to result in signs of ischemia on the surface electrocardiogram.

Cardiac Catheterization↗

PubMed2005

Comparison of the effects of a self-supervised home exercise program with a physiotherapist-supervised exercise program on the motor symptoms of Parkinson's disease.

The effects of a self-supervised home exercise program and a physiotherapist-supervised exercise program on motor symptoms in Parkinson's disease (PD) patients were compared in a prospective single-blinded clinical trial. Nineteen subjects (6 women, 13 men; mean age, 65 +/- 8 years) with Hoehn and Yahr Stages 2 to 3 were recruited. Subjects were self-selected into an 8-week exercise program that was self-supervised (HOME group) or physiotherapist-supervised (PT group). The primary outcome measurement was the Unified Parkinson's Disease Rating Scale (UPDRS) Motor subsection score (UPDRSm). The secondary outcome measurements were the Berg Balance Scale, Timed Up and Go Test, UPDRS Total score, and the Activities-specific Balance Confidence Scale. All outcomes were assessed at baseline and at 8 and 16 weeks after the start of the study. The investigators were blinded to the subject treatment group. Bonferroni-corrected paired Student's t test was used to evaluate the change in the UPDRSm from baseline to 8 weeks. Ninety-five percent confidence intervals (CI) were calculated for the change in the secondary outcome measurements from baseline to 8 weeks. There was statistically significant and equal decrease in the UPDRSm from baseline to 8 weeks in both treatment groups. There was no difference in the 95% CI in the change of the secondary outcome measurements. A self-supervised exercise program was found to have similar effectiveness as a physiotherapist-supervised exercise program in improving motor symptoms in PD patients. This finding is important in the counseling of PD patients regarding adjunctive treatment of motor symptoms of PD with exercise.

Aged↗

PubMed1997

Why exercise?: a preliminary investigation of an exercise motivation index among individuals with rheumatic conditions and healthy individuals.

The study was undertaken to investigate the test-retest stability and the criterion-related validity of a modified Swedish version of an exercise motivation index (EMI), and its use with individuals with rheumatic conditions, and with healthy individuals who exercised regularly. The EMI consists of 23 statements divided into three sub-scores for physical, psychological and social motivation. Ninety-five individuals with rheumatic conditions (mean age 60 years, mean symptom duration 15 years, 79% female) and 131 healthy individuals (mean age 52 years, 76% female), all attending exercise classes at least once a week, filled out the EMI. Sub-samples also filled out three visual analogue scales designed to measure physical, psychological and social exercise motivation, and filled out the EMI a second time one week later. The results indicated that psychological and physical exercise motivation was equally important in both samples. Social motivation was less important in both samples, but more pronounced in the rheumatic sample and among older individuals. In the rheumatic sample, physical motivation was more important among women and psychological motivation was more important among younger individuals. Test-retest stability for the EMI was satisfactory in both samples, while criterion-related validity was poor. The results of our preliminary investigation of the EMI suggest that the survey of physical, psychological and social motivation for exercise seems meaningful. Further work on the validity of the EMI is needed.

Case-Control Studies↗

PubMed1983

Physical exercise and digoxin binding to skeletal muscle: relation to exercise intensity.

The effect of a 1 h bicycle exercise test on digoxin concentration in skeletal muscle (thigh) and serum was studied in 10 healthy men, who had ingested digoxin 0.5 mg daily for 2 weeks. During maintenance digoxin treatment each subject performed 2 exercise tests, at 70-90 W and 140-180 W both 24 h after the last dose, at a 2-7 day interval. During exercise at the lower work load the mean skeletal muscle digoxin concentration increased by 9% (n.s.) and the mean serum digoxin concentration decreased by 26% (p less than 0.001). The high work load induced a mean increase in skeletal muscle digoxin of 20% (p less than 0.05) and a mean decrease in serum digoxin of 40% (p less than 0.001). The results indicate that the increased uptake of digoxin into exercised skeletal muscle and the decrease in serum digoxin during exercise is related to the intensity of the exercise.

Adult↗

PubMed1992

Influence of body position and pre-exercise activity on cardiac output and oxygen uptake following step changes in exercise intensity.

Parallel measurements of breath-by-breath oxygen uptake, cardiac output (Doppler technique), blood pressure (Finapres technique) and heart rate were performed in nine subjects during cycle ergometer exercise in the upright and supine positions. Transients were monitored during power steps starting from and leading to either rest or lower levels of exercise intensity. Oxygen uptake (VO2) and cardiac output kinetics were markedly faster than in all other conditions when exercise was started from rest. In contrast to exercise-exercise on steps, the computed arteriovenous difference in O2 content increased almost immediately in this situation, indicating that not only the additional energy expenditure due to the acceleration of the flywheel but also an increased venous admixture from non-exercising parts of the body contributed to the early kinetics. The off kinetics generally showed a more uniform pattern and did not simply mirror the on transients. The present findings indicate that transitions from rest should be avoided when muscle VO2 kinetics are to be assessed on the basis of VO2 measurements at the mouth.

Adult↗

PubMed1990

The effect of exercise intensity and duration on the oxygen deficit and excess post-exercise oxygen consumption.

Nine males with mean maximal oxygen consumption (VO2max) = 63.0 ml.kg-1.min-1, SD 5.7 and mean body fat = 10.6%, SD 3.1 each completed nine counterbalanced treatments comprising 20, 50 and 80 min of treadmill exercise at 30, 50 and 70% VO2max. The O2 deficit, 8 h excess post-exercise oxygen consumption (EPOC) and EPOC:O2 deficit ratio were calculated for all subjects relative to mean values obtained from 2 control days each lasting 9.3 h. The O2 deficit, which was essentially independent of exercise duration, increased significantly (P less than 0.05) with intensity such that the overall mean values for the three 30%, 50% and 70% VO2max workloads were 0.83, 1.89 and 3.09 l, respectively. While there were no significant differences (P greater than 0.05) between the three EPOCs after walking at 30% VO2max for 20 (1.01 l), 50 (1.43 l) and 80 min (1.04 l), respectively, the EPOC thereafter increased (P less than 0.05) with both intensity and duration such that the increments were much greater for the three 70% VO2max workloads (EPOC: 20 min = 5.68 l; 50 min = 10.04 l; 80 min = 14.59 l) than for the three 50% VO2max workloads (EPOC: 20 min = 3.14 l; 50 min = 5.19 l; 80 min = 6.10 l). An analysis of variance indicated that exercise intensity was the major determinant of the EPOC since it explained five times more of the EPOC variance than either exercise duration or the intensity times duration interaction. The mean EPOC:O2 deficit ratio ranged from 0.8 to 4.5 and generally increased with both exercise intensity and duration.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMedDate not supplied

Predicting severe ischemic events after uncomplicated myocardial infarction by exercise testing and rest and exercise radionuclide ventriculography.

BACKGROUND: In 183 patients with uncomplicated myocardial infarction, exercise-induced angina, ST segment depression, decrease in ejection fraction, or inadequate increase in systolic blood pressure and low exercise tolerance were significantly associated with 4-year incidence of hard ischemic events. METHODS AND RESULTS: Only the onset of both ST segment depression and a decrease in left ventricular ejection fraction with exercise was an independent predictor. ST segment depression and decrease in left ventricular ejection fraction had low sensitivity (61% and 70%) and specificity (56% and 51%) for hard ischemic events, but specificity increased to 78% when both were present. During medical therapy, 22 of 53 patients with both ST segment depression and a decrease in left ventricular ejection fraction with exercise had an ischemic event (i.e., 48.1% 4-year probability on Kaplan-Meier analysis vs 19.2% in the remaining 130 patients [p < 0.0005]). CONCLUSIONS: Even if no single variable, derived from exercise testing, is a highly sensitive and specific predictor, specificity increases to a clinically relevant level by combining ST segment depression and a decrease in left ventricular ejection fraction with exercise, and in this way patients with recent infarction may be selected for coronary arteriography.

Adult↗

PubMedDate not supplied

Exercise tolerance and blood pressure response to exercise testing in children and adolescents after renal transplantation.

The aim of the study was to assess exercise tolerance and blood pressure (BP) response to treadmill exercise in children after renal transplantation. Forty-five children were selected (29 males and 16 females) whose mean age was 14.3 +/- 4.2 years. All children had Hb >/= 10 g/dl and creatinine clearance >/=40 ml/min/1.73 m2. They were at least 6 months posttransplantation and were on triple immunosuppressive therapy. Twenty-seven were also on various antihypertensive medications. Each underwent clinical examination and measurement of BP, both at rest and during exercise testing on treadmill. The test was stopped on muscular fatigue or exhaustion. The patients were divided into two groups: those off (A) or on (B) antihypertensive therapy. When compared to a population of healthy children the patients had reduced exercise tolerance (10.1 +/- 2.1 vs 15.1 +/- 1.7 min, p < 0.001) (67 +/- 16%), increased heart rate (174 +/- 19 vs 161 +/- 19 beats/min, p < 0.001) (109 +/- 15%), and increased maximum systolic BP (150 +/- 26 vs 134 +/- 13 mmHg, p < 0. 001) (113 +/- 19%) at comparable workloads. Within the two patient groups, significant differences were observed during exercise testing for maximum heart rate, which was lower in group B (p = 0.03), and maximum systolic BP, which was higher in group A (p = 0.04). Our study confirms that children and adolescents on immunosuppressive therapy after renal transplantation have a hypertensive response during exercise, probably related to medication-induced peripheral vascular tone.

Adolescent↗

PubMed1999

Thallium-201 right lung/heart ratio during exercise in patients with coronary artery disease: relation to thallium-201 myocardial single-photon emission tomography, rest and exercise left ventricular function and coronary angiography.

The aim of this study was to correlate lung thallium-201 uptake on exercise with 201Tl single-photon emission tomography (SPET) myocardial perfusion imaging, rest and exercise equilibrium radionuclide angiographic and coronary angiographic findings in patients with coronary artery disease (CAD) using a simple, reproducible lung/heart (L/H) ratio that would be easy to use in clinical practice. L/H ratio was defined on the anterior planar image obtained during exercise 201Tl SPET acquisition as the mean counts per pixel in an entire right lung field region of interest divided by the mean counts per pixel in the hottest myocardial wall region of interest. We studied 103 patients. Fifty-nine patients (group I) with <5% likelihood of CAD were used as a reference group. In 44 CAD patients (group II), L/H ratio was compared with 201Tl SPET, radionuclide angiographic and coronary angiographic variables. The group I L/H ratio of 0.35+/-0.05 (mean +/-1 SD) was significantly lower (P<0.001) than the group II L/H ratio of 0. 45+/-0.10. An L/H ratio >0.45 (mean + 2 SD in group I) was considered abnormal. In group II, L/H ratio showed a significant correlation with stress and rest 201Tl perfusion defect size (r = 0. 39 and r = 0.42, P<0.01, respectively), but not with extent of ischaemic myocardium. The mean L/H ratio was 0.41+/-0.10 in patients with one-vessel disease (n = 15), 0.46+/-0.08 in those with two-vessel disease (n = 17) and 0.47+/-0.12 in those with three-vessel disease (n = 12), but no significant difference was found between the three subgroups. L/H ratio showed a significant inverse relation with rest and exercise left ventricular ejection fraction (r = -0.37 and r = -0.50, P<0.05 and P<0.001, respectively). Using stepwise multiple regression analysis, exercise left ventricular ejection fraction and previous history of hypertension were the sole two variables independently predictive of the L/H ratio. In conclusion, although lung thallium uptake is usually found to correlate with extent and severity of CAD, increased L/H ratio should primarily be considered as a marker of exercise-induced left ventricular systolic and perhaps diastolic dysfunction, probably independent of the underlying cardiac disease.

Case-Control Studies↗

PubMed2003

Effects of priming exercise intensity on the dynamic linearity of the pulmonary VO(2) response during heavy exercise.

Prior heavy-intensity exercise facilitates the pulmonary oxygen uptake ( VO(2)) response during subsequent exercise, such that its kinetics returns towards first-order. To better understand this "priming" phenomenon, we investigated the effect of priming exercise, over a range of intensities, on the VO(2) response to heavy-intensity cycle ergometry at a work rate of Delta50% [halfway between lactate threshold (LT) and VO(2max)]. Eight subjects performed two consecutive 6-min bouts separated by 6 min at 20 W. The first bout was each of: no warm-up control (CON), sub-lactate threshold (LT) at 80% of LT, and three supra-LT conditions (Delta20%, Delta40%, and Delta60%). The VO(2) response during the subsequent bout was evaluated using the "effective" time constant (tau'), and the VO(2) difference between minutes 3 and 6 (Delta VO(2(6-3))). The goodness-of-fit, indicative of "first-order" kinetics, was determined by the residual profile, and the mean square of errors (MSEr). The heart rate and blood lactate concentration ([La]r) just prior to the second bout were also measured. Compared with CON, tau' and Delta VO(2(6-3)) were significantly reduced following all supra-LT priming bouts, while the goodness-of-fit was significantly improved following Delta40% exercise. Delta VO(2(6-3)) and [La]r were negatively correlated ( P<0.05), unlike HR. In conclusion, prior exercise just above, but not below, LT facilitated the VO(2) response in a threshold-like manner. Supra-LT priming exercise influenced the VO(2) response allowing it to return to within as little as 12% from first-order (compared to approximately 50% in CON). The associated increases in circulating lactate and/or related factors seem to be centrally involved in this phenomenon.

Adaptation, Physiological↗

PubMed2006

Ventilatory and circulatory responses at the onset of exercise after eccentric exercise.

The purpose of this study was to clarify whether delayed onset muscle soreness (DOMS) and muscle damage after eccentric exercise (ECC) could affect the ventilatory and circulatory responses at the onset of exercise, and whether those effects would continue after the disappearance of DOMS. Ten males participated in this study. We measured ventilatory and circulatory responses at the onset of exercise, for the first 20 s, during knee extension-relaxation voluntary exercise (VOL) and passive movement (PAS), which was achieved by the experimenter alternatively pulling ropes connected to the subjects' ankles for the same period and frequency as during VOL. VOL and PAS were performed before, 2 days after, and 7 days after ECC. The following results were found: (1) the gain of minute ventilation at the onset of VOL at 2 days after ECC was significantly larger than that of before ECC; (2) the gain of minute ventilation at 7 days after ECC during both VOL and PAS was also enhanced significantly as compared to that of before ECC; and (3) heart rate and blood pressure responses were unchanged throughout the experimental period. In conclusion, ventilatory response at the onset of exercise is augmented during DOMS and EIMD after ECC and the enhanced ventilatory response continued after the disappearance of DOMS. It is suggested that enhanced ventilatory response during exercise after ECC is attributed to at least the changes in neural factors and that the mechanisms inducing these augmented ventilatory responses should be different during the period after ECC.

Adult↗

PubMed1997

Metabolic and hormonal responses during repeated bouts of brief and intense exercise: effects of pre-exercise glucose ingestion.

We investigated metabolic and hormonal responses during repeated bouts of brief and intense exercise (a force-velocity test; Fv test) and examined the effect of glucose ingestion on these responses and on exercise performance. The test was performed twice by seven subjects [27 (2) years] according to a double-blind randomized crossover protocol. During the experimental trial (GLU), the subjects ingested 500 ml of glucose polymer solution containing 25 g glucose 15 min before starting the exercise. During the control trial (CON), the subjects received an equal volume of sweet placebo (aspartame). Exercise performance was assessed by calculating peak anaerobic power (W(an,peak)). Venous plasma lactate concentration increased significantly during the Fv test (P < 0.001), but no difference was found between CON and GLU. Blood glucose first decreased significantly from the beginning of exercise up to the 6-kg load (P < 0.001) and then increased significantly at W(an,peak) and for up to 10 min during the recovery period (P < 0.001) in both CON and GLU. Insulin concentrations decreased significantly in both groups, but were higher at W(an,peak) in GLU compared with CON (P < 0.05). Glucagon and epinephrine did not change significantly in either group, but epinephrine was significantly lower in GLU after glucose ingestion (P < 0.05) and at W(an,peak) (P < 0.05). W(an,peak) was not significantly different between CON and GLU. In conclusion, blood glucose and insulin concentrations decreased during repeated bouts of brief and intense exercise, while blood lactate concentration increased markedly without any significant change in glucagon and epinephrine concentrations. Glucose ingestion altered metabolic and hormonal responses during the Fv test, but the performance as measured by W(an,peak) was not changed.

Adult↗

PubMed2005

The role of exercise on platelet aggregation in patients with stable coronary artery disease: exercise induces aspirin resistant platelet activation.

OBJECTIVES: The aim of our study was to determine the relation between exercise stress test and aspirin resistance in patients with stable coronary artery disease. BACKGROUND: Clinically aspirin resistance is defined as having thrombotic and embolic cardiovascular events despite regular aspirin therapy. METHODS: We studied platelet functions of 62 patients with stable coronary artery disease and 20 subjects with normal coronary arteries by Platelet Function Analyzer (PFA-100, Dade Behring, Germany) at rest and after exertion with collagen and/or epinephrine (Col/Epi) and collagen and/or ADP cartridges. Closure time (CT)<186 seconds was defined as aspirin resistance with Col/Epi cartridges of PFA-100. Symptom limited treadmill stress test (protocol of Bruce) was performed with Oxford Streslink TD-1 system. RESULTS: 8 (12.9%) patients were aspirin resistant by PFA-100 (CT<186s despite regular aspirin therapy) at rest. At the first minute of the recovery period of exercise stress test 14 (22.5%) patients were aspirin resistant by PFA-100. CTs with Col/ADP were respectively 89+/-6 s (83--100s) and 89+/-5 s (82--104s) at rest and after exercise (p=0.107). 20.3% (11/54) of patients known as in vitro aspirin sensitives at rest had shorter CTs and 11.1% (6/54) had aspirin resistance after exercise (p=0.004). There was no statistically significiant difference in platelet functions in the control group after exertion. CONCLUSION: We conclude that 11.1% of in vitro aspirin sensitive subjects at rest had aspirin resistance after exercise by PFA-100. In some individuals, exercise induced platelet activation is aspirin insensitive at usual antiplatelet doses. We need further clinical trials to optimize antiplatelet therapy in patients with coronary artery disease.

Adult↗