Biomedical subjects

J Myll

Publications and source records attributed to J Myll.

4 recordsLinked to original sources

PubMed2000

Physical functioning and health-related quality-of-life changes with exercise training in hemodialysis patients.

The Renal Exercise Demonstration Project was designed to test the effects of two different approaches to exercise programming on the levels of physical activity, physical functioning, and self-reported health status in hemodialysis patients. Two hundred eighty-six patients were recruited for participation. Intervention patients were given individually prescribed exercise for 8 weeks of independent home exercise, followed by 8 weeks of incenter cycling during dialysis. Physical performance testing was performed at baseline and after each intervention using gait speed, sit-to-stand test, and 6-minute walk. The Medical Outcomes Study Short Form 36-item (SF-36) questionnaire was used to assess self-reported health status. The intervention group showed increased participation in physical activity. There were significant differences between the intervention and nonintervention groups in change over time in normal and fast gait speed, sit-to-stand test scores, and the physical scales on the SF-36, including the physical component scale. The intervention group improved in these test results, whereas the nonintervention group either did not change or declined over the duration of the study. It is clear that improvements in physical functioning result from exercise counseling and encouragement in hemodialysis patients. Because self-reported physical functioning is highly predictive of outcomes in hemodialysis patients, more attention to patients' levels of physical activity is warranted.

Activities of Daily Living↗

PubMed2000

Low-functioning hemodialysis patients improve with exercise training.

The Renal Exercise Demonstration Project provided two different approaches to exercise programming to a group of hemodialysis patients. Physical functioning and self-reported health-related quality of life were measured at baseline, after 2 months of independent exercise, and again after 2 months of in-center cycling. This study compares the responses to intervention of patients who initially scored low (<34) on the Physical Component Scale (PCS) on the Medical Outcomes Study Short-Form 36 questionnaire to those who initially scored higher (>34) on the same scale. The high-PCS group scored higher on all physical function tests (normal gait speed, fast gait speed, and sit-to-stand test) at each testing time than the low-PCS group. The high-PCS group improved only on the sit-to-stand test, whereas the low-PCS group improved in all three physical function tests. There were significant differences between the groups in change over time in all the physical scales and the PCS over time, with the low-PCS group showing improvements in response to the intervention and the high-PCS group showing no change over time. No differences in change over time were noted between the groups on the mental scales in either group. We conclude that low-functioning hemodialysis patients can benefit from exercise counseling in both objective measures of physical functioning and self-reported physical functioning. The impact of such interventions seems to be more profound in the lowest functioning patients.

Analysis of Variance↗

PubMed1994

Effects of cessation of caffeinated-coffee consumption on ambulatory and resting blood pressure in men.

Coffee consumption has been weakly linked to high blood pressure (BP). The hypothesis that cessation of caffeinated-coffee consumption lowers ambulatory BP was tested in men in a randomized trial. One hundred eighty-six middle-aged, normotensive, male, habitual caffeinated-coffee consumers were recruited. Of these subjects, 150 had sufficiently complete, ambulatory BP measurements for analysis. After 2 months of standard caffeinated-coffee consumption, subjects were randomized to consume an equal amount of the same standard caffeinated coffee or a standard decaffeinated coffee, or to discontinue coffee consumption for 2 months. Diet composition, body weight and exercise did not change. Resting BP and heart rate were not different between the groups before and after intervention. In comparison with the continued caffeinated-coffee group (control), the decaffeinated-coffee group revealed significant reductions in mean ambulatory systolic BP during the morning (-4.0 +/- 11 mm Hg; p = 0.014), afternoon (-5.3 +/- 10 mm Hg; p = 0.001) and evening (-3.2 +/- 10 mm Hg; p = 0.003) hours, reductions in mean ambulatory diastolic BP during the afternoon (-1.8 +/- 10 mm Hg; p = 0.063) and evening (-1.8 +/- 10 mm Hg; p = 0.059) hours and no change in ambulatory heart rate.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1993

Coronary artery size and dilating capacity in ultradistance runners.

BACKGROUND: Increases in coronary artery size and dilating capacity have been observed in some animals after endurance training, and at autopsy, active men appear to have enlarged epicardial coronary arteries. This cross-sectional study was designed to test the hypothesis that highly trained endurance runners have larger epicardial coronary arteries and greater dilating capacity than inactive men. METHODS AND RESULTS: The subjects, ages 39-66 years, included 11 male volunteers who had participated in ultradistance running during the past 2 years and 11 physically inactive men who had been referred for arteriography but had no visible coronary artery disease. The internal diameter of the proximal segments of each major epicardial coronary artery was measured before and after nitroglycerin administration using a computer-based quantitative arteriographic analysis system. Measurements also included maximal oxygen uptake, plasma lipoprotein concentrations, body composition, and cardiac mass by echocardiography. Before nitroglycerin, the sum of the cross-sectional areas for the proximal right, left anterior descending, and circumflex arteries was not different for the runners and the inactive men: 22.7 +/- 4.79 versus 21.0 +/- 7.97 mm2 (p = 0.57), respectively. However, the increase in the sum of the cross-sectional area for the proximal right, left anterior descending, and circumflex arteries in response to nitroglycerin was greater for the runners (13.20 +/- 4.76 versus 6.00 +/- 3.02 mm2; p = 0.002). Left ventricular mass index (152 +/- 21 versus 116 +/- 41 g/m2; p < 0.05) but not left ventricular mass (284 +/- 40 versus 246 +/- 91 g; p = 0.22) was significantly greater for the runners. Among the runners, dilating capacity was positively correlated with aerobic capacity and negatively related to adiposity, resting heart rate, and plasma lipoprotein concentrations. CONCLUSIONS: Highly trained, middle-aged endurance runners demonstrated a significantly greater dilating capacity of their epicardial coronary arteries in response to nitroglycerin compared with inactive men. The causes of this greater dilating capacity and its clinical significance need to be determined.

Adult↗