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The Activity Counseling Trial (ACT) is a multicenter, randomized controlled trial to evaluate the effectiveness of interventions to promote physical activity in the primary health care setting. ACT has recruited, evaluated, and randomized 874 men and women 35-75 yr of age who are patients of primary care physicians. Participants were assigned to one of three educational interventions that differ in amount of interpersonal contact and resources required: standard care control, staff-assisted intervention, or staff-counseling intervention. The study is designed to provide 90% power in both men and women to detect a 1.1 kcal.kg-1.day-1 difference in total daily energy expenditure between any two treatment groups, and over 90% power to detect a 7% increase in maximal oxygen uptake, the two primary outcomes. Primary analyses will compare study groups on mean outcome measures at 24 months post-randomization, be adjusted for the baseline value of the outcome measure and for multiple comparisons, and be conducted separately for men and women. Secondary outcomes include comparisons between interventions at 24 months of factors related to cardiovascular disease (blood lipids/lipoproteins, blood pressure, body composition, plasma insulin, fibrinogen, dietary intake, smoking, heart rate variability), psychosocial effect, and cost-effectiveness, and at 6 months for primary outcome measures. ACT is the first large-scale behavioral intervention study of physical activity counseling in a clinical setting, includes a generalizable sample of adult men and women and of clinical setting, and examines long-term (24 months) effects. ACT has the potential to make substantial contributions to the understanding of how to promote physical activity in the primary health care setting.

A review of research on complementary and alternative treatments, specifically mind-body techniques, was conducted at Stanford University. The goals of the review were to establish a comprehensive literature review and to provide a rationale for future research concerning successful aging.Computerized searches were conducted using MEDLINE, PsychInfo, Stanford Library, Dissertation Abstracts, Lexus-Nexus, the Internet, and interviews conducted with practitioners. All studies since 1990 that examined mind-body treatments of cardiovascular disorders in the elderly were included. Mind-body practices evaluated were social support, cognitive-behavioral treatment, meditation, the placebo effect, hope, faith, imagery, spiritual healing, music therapy, hypnosis, yoga, t'ai chi, qigong and aikido. Studies conducted after 1990 were a priority, but when more recent literature was scarce, other studies using randomized, controlled trials were included.Mind-body techniques were found to be efficacious primarily as complementary and sometimes as stand-alone alternative treatments for cardiovascular disease-related conditions. Studies provided evidence for treatment efficacy, but the need for further controlled research was evident.Reviewers found only a handful of randomized, controlled research studies conducted in the United States. As a result, there is a lack of replicated studies with which to determine appropriate treatment dosage and the mechanisms by which many of the practices work. Compelling anecdotal evidence, the presence of some controlled research, overall cost effectiveness, and the lack of side effects resulting from mind-body treatments make further investigation a high priority.

To determine the effects of moderate-intensity exercise training on self-rated (subjective) sleep quality among healthy, sedentary older adults reporting moderate sleep complaints.Randomized controlled trial of 16 weeks' duration.General community.Volunteer sample of 29 women and 14 men (of 67 eligible subjects) aged 50 to 76 years who were sedentary, free of cardiovascular disease, and reported moderate sleep complaints. No participant was withdrawn for adverse effects.Randomized to 16 weeks of community-based, moderate-intensity exercise training or to a wait-listed control condition. Exercise consisted primarily of four 30- to 40-minute endurance training sessions (low-impact aerobics; brisk walking) prescribed per week at 60% to 75% of heart rate reserve based on peak treadmill exercise heart rate.Pittsburgh Sleep Quality Index (PSQI).Compared with controls (C), subjects in the exercise training condition (E) showed significant improvement in the PSQI global sleep score at 16 weeks (baseline and posttest values in mean [SD] for C=8.93 [3.1] and 8.8 [2.6]; baseline and posttest values for E=8.7 [3.0] and 5.4 [2.8]; mean posttest difference between conditions=3.4; P.001; 95% confidence interval, 1.9-5.4), as well as in the sleep parameters of rated sleep quality, sleep-onset latency (baseline and posttest values for C=26.1 [20.0] and 23.8 [15.3]; for E=28.4 [20.2] and 14.6 [13.0]; net improvement=11.5 minutes), and sleep duration baseline and posttest scores for C=5.8 [1.1] and 6.0 [1.0]; for E=6.0 [1.1] and 6.8 [1.2]; net improvement=42 minutes) assessed via PSQI and sleep diaries (P=.05).Older adults with moderate sleep complaints can improve self-rated sleep quality by initiating a regular moderate-intensity exercise program.

Previous studies have shown that alendronate can increase bone mineral density (BMD) and prevent radiographically defined (morphometric) vertebral fractures. The Fracture Intervention Trial aimed to investigate the effect of alendronate on the risk of morphometric as well as clinically evident fractures in postmenopausal women with low bone mass.Women aged 55-81 with low femoral-neck BMD were enrolled in two study groups based on presence or absence of an existing vertebral fracture. Results for women with at least one vertebral fracture at baseline are reported here. 2027 women were randomly assigned placebo (1005) or alendronate (1022) and followed up for 36 months. The dose of alendronate (initially 5 mg daily) was increased (to 10 mg daily) at 24 months, with maintenance of the double blind. Lateral spine radiography was done at baseline and at 24 and 36 months. New vertebral fractures, the primary endpoint, were defined by morphometry as a decrease of 20% (and at least 4 mm) in at least one vertebral height between the baseline and latest follow-up radiograph. Non-spine clinical fractures were confirmed by radiographic reports. New symptomatic vertebral fractures were based on self-report and confirmed by radiography.Follow-up radiographs were obtained for 1946 women (98% of surviving participants). 78 (8.0%) of women in the alendronate group had one or more new morphometric vertebral fractures compared with 145 (15.0%) in the placebo group (relative risk 0.53 [95% Cl 0.41-0.68]). For clinically apparent vertebral fractures, the corresponding numbers were 23 (2.3%) alendronate and 50 (5.0%) placebo (relative hazard 0.45 [0.27-0.72]). The risk of any clinical fracture, the main secondary endpoint, was lower in the alendronate than in the placebo group (139 [13.6%] vs 183 [18.2%]; relative hazard 0.72 [0.58-0.90]). The relative hazards for hip fracture and wrist fracture for alendronate versus placebo were 0.49 (0.23-0.99) and 0.52 (0.31-0.87). There was no significant difference between the groups in numbers of adverse experiences, including upper-gastrointestinal disorders.We conclude that among women with low bone mass and existing vertebral fractures, alendronate is well tolerated and substantially reduces the frequency of morphometric and clinical vertebral fractures, as well as other clinical fractures.

The 12-month effects of exercise training on psychological outcomes in adults ages 50-65 years were evaluated. Ss (N = 357) were randomly assigned to assessment-only control or to higher intensity group, higher intensity home, or lower intensity home exercise training. Exercisers showed reductions in perceived stress and anxiety in relation to controls (p.04). Reductions in stress were particularly notable in smokers. Regardless of program assignment, greater exercise participation was significantly related to less anxiety and fewer depressive symptoms, independent of changes in fitness or body weight (p.05). It was concluded that neither a group format nor vigorous activity was essential in attaining psychological benefits from exercise training in healthy adults.

To determine the effectiveness of group- vs home-based exercise training of higher and lower intensities among healthy, sedentary older adults.--Year-long randomized, controlled trial comparing (1) higher-intensity group-based exercise training; (2) higher-intensity home-based exercise training; (3) lower-intensity home-based exercise training; or (4) assessment-only control.--General community located in northern California.--One hundred sixty women and 197 men 50 to 65 years of age who were sedentary and free of cardiovascular disease. One out of nine persons contacted through a community random-digit-dial telephone survey and citywide promotion were randomized.--For higher-intensity exercise training, three 40-minute endurance training sessions per week were prescribed at 73% to 88% of peak treadmill heart rate. For lower-intensity exercise training, five 30-minute endurance training sessions per week were prescribed at 60% to 73% of peak treadmill heart rate.--Treadmill exercise test performance, exercise participation rates, and heart disease risk factors.--Compared with controls, subjects in all three exercise training conditions showed significant improvements in treadmill exercise test performance at 6 and 12 months (P less than .03). Lower-intensity exercise training achieved changes comparable with those of higher-intensity exercise training. Twelve-month exercise adherence rates were better for the two home-based exercise training conditions relative to the group-based exercise training condition (P less than .0005). There were no significant training-induced changes in lipid levels, weight, or blood pressure.--We conclude that (1) this community-based exercise training program improved fitness but not heart disease risk factors among sedentary, healthy older adults; (2) home-based exercise was as effective as group exercise in producing these changes; (3) lower-intensity exercise training was as effective as higher-intensity exercise training in the home setting; and (4) the exercise programs were relatively safe.

To determine the response to repeated treadmill exercise testing soon after uncomplicated myocardial infarction, 24 males (mean age 54 +/- 6 years) performed two symptom-limited tests several days apart 3, 7 and 11 weeks after the acute event. Significant within-week differences were noted for peak exercise tolerance (mets) and peak heart rate at 7 weeks (p less than 0.05). Significant within-week differences in these variables were not noted for other weeks or for systolic blood pressure or heart rate-systolic blood pressure product for any of the three test periods. No significant within-week differences were noted for any variable recorded at a submaximal work load of 4 mets. The frequency of exercise-induced ischemic ST-segment depression, angina pectoris and premature ventricular complexes did not change from visit to visit and was highly reproducible (p less than 0.01). All test variables measured at peak exercise increased significantly between 3 and 11 weeks after infarction. We conclude that cardiovascular responses to symptom-limited exercise testing are highly reproducible in the 3 months after uncomplicated myocardial infarction. Changes in the response to treadmill exercise tests performed several weeks apart reflect alterations in cardiovascular performance.

Medically directed at-home rehabilitation was compared with group rehabilitation which began 3 weeks after clinically uncomplicated acute myocardial infarction (AMI) in 127 men, mean age 53 ± 7 years. Between 3 and 26 weeks after AMI, adherence to individually prescribed exercise was equally high (at least 71%), the increase in functional capacity equally large (1.8 ± 1.0 METs) and nonfatal reinfarction and dropout rates equally low (both 3% or less) in the 66 men randomized to home training and the 61 men randomized to group training. No training-related complications occurred in either group. The low rate of reinfarction and death (5% and 1%, respectively) in the study as a whole, which included 34 patients with no training and 37 control patients, reflected a stepwise process of clinical evaluation, exercise testing at 3 weeks and frequent telephone surveillance of patients who underwent exercise training. Medically directed at-home rehabilitation has the potential to increase the availability and to decrease the cost of rehabilitating low-risk survivors of AMI.

The Stanford Five-City Project is a long-term field evaluation of the effects of community health education on cardiovascular disease risk factors and event rates. One major end point of the project is the difference between treatment and control group trends in morbidity and mortality rates ascertained through community-wide surveillance of deaths and hospital discharges. This surveillance system includes continuous review of death certificates and hospital discharge records, interviews with the families and physicians of decedents who died outside the hospital, abstraction of the hospital records of possible myocardial infarction and stroke cases (fatal and nonfatal), and systematic validation of diagnosis by the use of standard criteria. Initial experience with information access, availability of diagnostic information, costs, and reliability are described. This standardized approach to community surveillance of cardiovascular disease events rates, both fatal and nonfatal, is a feasible method for evaluating large-scale intervention programs and may be applicable to monitoring secular trends in the absence of intervention.

During the Lipid Research Clinics North American Prevalence Study, plasma lipoprotien determinations and treadmill exercise testing were performed on 2319 white men and 2067 white women ages 20 years or older randomly selected from population surveys by nine clinics in the U.S. and Canada. Before exercise testing, participants were asked if they performed any strenuous physical activity on a regular basis. Data were analyzed to determine the relationship of plasma high-density lipoprotein (HDL) cholesterol to treadmill exercise test performance and a self-report of strenuous activity. Neither treadmill exercise test duration nor heart rate response to submaximal exercise was significantly related to HDL cholesterol levels for either men or women. However, participants who reported some strenuous physical activity generally had higher HDL cholesterol levels than those who reported none, and the more active men ages 30-49 years and active women ages 20-39 had significantly higher values (p0.05). When HDL cholesterol was adjusted for age, body mass index, alcohol use, cigarette smoking and interclinic population variation, more active men (47.1 vs 45.2 mg/dl; p = 0.0001) and more active women (59.6 vs 57.7 mg/dl; p = 0.02) had higher HDL cholesterol levels than their sedentary counterparts. Thus, the association between HDL cholesterol and reported physical activity was, at least in part, independent of other factors that influence HDL cholesterol concentration, but was not associated with exercise tolerance as determined by treadmill exercise testing.

Exercise exerts both acute and chronic effects on plasma lipid and lipoprotein concentrations. Much of the triglyceride-lowering effect is an acute response, with the changes in cholesterol having a greater chronic component. The acute Tg decrease seems to be due to accelerated catabolism resulting from increased LPL activity. Following exercise, and on a more chronic basis, decreased VLDL-Tg synthesis may also occur in response to an increase in tissue insulin sensitivity. The low body fat content of endurance-trained athletes also contributes to lower Tg concentrations, through this same mechanism. The magnitude of the plasma Tg response to acute or chronic exercise is highly influenced by preexercise values--decreases in plasma Tg occur only when preexercise values are elevated. The major exercise effect on plasma cholesterol appears to be an increase in HDL-C as a result of endurance training, very likely related to the increase in LPL activity and Tg catabolism. This response is not always achieved with exercise training, and has been especially difficult to demonstrate in previously sedentary women. Exercise effects on HDL-C may be augmented by weight loss or changes in nutrient intake, but these interrelationships are not well established. A dose-response relationship exists, with the lower threshold influenced by baseline HDL-C values and exercise status. The higher HDL-C associated with endurance training is the result of increases in the less dense HDL2 subfraction, with elevations in both the lipid and protein components. Relatively small decreases in LDL-C occur with training. The biological mechanisms for these exercise effects have not been established.

The Sphygmetrics SR-2 Automatic Blood Pressure Recorder uses an infrasonic technique for detecting artery wall motion to estimate systemic arterial pressure and produces a permanent record of the results. It therefore is potentially useful in reducing observer bias in epidemiologic studies of blood pressure (BP). Two blood pressures were recorded in 21 men and 50 women using the SR-2 simultaneously with two auscultators using a biaural stethoscope and mercury syhgmomanometer. The SR-2 measured slightly higher systolic nd slightly lower diastolic pressures on average, but the differences were not significant. The two auscultators were highly correlated with one another (r = 0.99 systolic/0.97 diastolic) and with the SR-2 (0.93 and 0.92 for systolic, 0.84 and 0.85 for diastolic). The correlations were unrelated to sex, age, or antihypertensive medication status, but the correlations between th SR-2 and either auscultator for diastolic BP were quite low (0.36, 0.55) in subjects whose relative weight was below 1.0. Interpretation of the SR-2 disc was very reliable, with inter- and intra-reader correlations being 0.99 for systolic and 0.84 to 0.94 for diastolic. The SR-2 was found to be comparable to auscultation in estimating systolic BP in a heterogeneous population which has the advantages of reducing observer bias and producing a permanent record. Its use in estimating diastolic pressure in thin individuals and children needs further evaluation.

This paper presents the results of an analysis of dietary alcohol use and blood pressure in representative population samples from four northern California cities surveyed in 1979-1980 as part of the Stanford Five City Project. The pooled samples included 883 men and 959 women aged 20-74 who were not taking blood pressure medications. Blood pressure was obtained while seated using a standard manometer. Alcohol was assessed by self-report of usual intake. In men, age-specific analysis revealed a positive association between dietary alcohol and both systolic (SBP) and diastolic blood pressure (DBP). The association was linear in men aged 20-34 and 50-74 and was stronger in the oldest men. Both linear and quadratic terms were significant for men aged 35-49. This association remained significant in a linear regression model that included age, relative weight, income, education, physical activity, cigarette use, and untimed urinary sodium/creatinine; for alcohol in ml/day in men aged 50-74, beta = 0.21, p = 0.0001, R2 = 0.32 for SBP; beta = 0.09, p = 0.0002, R2 = 0.18 for DBP. In women, alcohol use was significantly associated with blood pressure only in those above age 49 and was more striking in those not taking estrogens; this association was also independent of the same variables listed above for men (beta = 0.43, p = 0.0001, R2 = 0.23 for SBP; beta = 0.17, p = 0.001, R2 = 0.13 for DBP). Multiple logistic analyses with hypertension as a dichotomous dependent variable and including all subjects showed similar results. These results could be due to any one or more of the following hypotheses: 1) a biologic response to alcohol in older men and in older women that is different from the response in younger persons; 2) a delayed effect of alcohol use on blood pressure; 3) effects of a different pattern of alcohol use in the different age groups; or 4) the presence of some unmeasured confounding factor in the older age groups.

In a defined population of 4349 men and 3398 women, we evaluated the frequency and clustering of five nonlipid coronary heart disease risk factors--obesity, hypertension, sedentary lifestyle, cigarette smoking, and alcohol consumption--in nine categorical lipoprotein phenotypes--normal, types I or V, IIA, IIB, III, IV, hypoHDL (high-density lipoprotein), hypoLDL (low-density lipoprotein), and hyperHDL. This analysis indicated that compared with the normal phenotype, nonlipid coronary risk factors tend to be more frequent and thus cluster in individuals with "high risk" phenotypes, and occur somewhat less frequently in those with "low risk" phenotypes. Thus, identification of a high-risk phenotype suggests the presence of nonlipid risk factors as well, and the clinician should be alert to this possibility. A multivariable analysis of the independent associations of each of the risk factors with the lipid and lipoprotein components that define the phenotypes suggested that several behavioral risk factors may directly affect lipid and lipoprotein levels. This observation raises the possibility that certain intervention strategies, such as weight loss, smoking cessation, and regular exercise, may favorably influence dyslipoproteinemia.

Previous measures of physical activity for epidemiologic studies were considered inadequate to meet the needs of a community-based health education trial. Therefore, new methods of quantifying the physical activity habits of communities were developed which are practical for large health surveys, provide information on the distribution of activity habits in the population, can detect changes in activity over time, and can be compared with other epidemiologic studies of physical activity. Independent self-reports of vigorous activity (at least 6 metabolic equivalents (METs) ), moderate activity (3-5 METs), and total energy expenditure (kilocalories per day) are described, and the physical activity practices of samples of California cities are presented. Relationships between physical activity measures and age, education, occupation, ethnicity, marital status, and body mass index are analyzed, and the reliabilities of the three activity indices are reported. The new assessment procedure is contrasted with nine other measures of physical activity used in community surveys.

Heart rate, determined by palpation of the carotid, radial, or temporal artery, is commonly used to monitor exercise intensity. It is known that massage of the carotid artery has a baroreceptor reflex effect on the heart rate. The heart rate, monitored with and without carotid palpation, at rest, during exercise, and immediately post-exercise was determined in 60 male cardiac patients (39-65 years of age) following either myocardial infarction (n=52), bypass surgery (n=6), or those with angina pectoris (n=2). The mean changes in heart rate with carotid palpation in the testing group were -3.5 bpm at rest and -2.2 bpm during exercise; in the training group the changes were +0.8 bpm at rest -3.1 bpm post exercise. While the mean decrease at rest in the testing group was statistically significant, each of the decreases in resting, during, and post-exercise heart rates were too small to be accurately monitored by palpation over a 10- or 15-sec count, a usual procedure in exercise rehabilitation programs. Provided the patients are correctly instructed and technique regularly checked, there appears to be no reason why carotid palpation should not be used in cardiac exercise rehabilitation programs to determine resting, exercise, or post-exercise heart rates.

Limited data are available on the relation between physical fitness and mortality from cardiovascular disease. We examined this question in a study of 4276 men, 30 to 69 years of age, whom we followed for an average of 8.5 years. Examinations at base line included assessment of conventional coronary risk factors and treadmill exercise testing. The heart rate during submaximal exercise (stage 2 of the exercise test) and the duration of exercise were used as measures of physical fitness. Men with incomplete data (n = 308) or who were using cardiovascular drugs (n = 213) were excluded from the analysis. Men who had clinical evidence of cardiovascular disease at base line (n = 649) were analyzed separately. Forty-five deaths from cardiovascular causes occurred among the remaining 3106 men. A lower level of physical fitness was associated with a higher risk of death from cardiovascular and coronary heart disease, after adjustment for age and cardiovascular risk factors. The relative risk of death from cardiovascular causes was 2.7 (95 percent confidence interval, 1.4 to 5.1; P = 0.003) for healthy men with an increment of 35 beats per minute in the heart rate during stage 2, and 3.0 (95 percent confidence interval, 1.6 to 5.5; P = 0.0004) for those with a decrement of 4.4 minutes in the exercise time spent on the treadmill. The corresponding values for death from coronary heart disease were 3.2 (95 percent confidence interval, 1.5 to 6.7; P = 0.003) and 2.8 (95 percent confidence interval, 1.3 to 6.1; P = 0.007), respectively. We conclude that a lower level of physical fitness is associated with a higher risk of death from coronary heart disease and cardiovascular disease in clinically healthy men, independent of conventional coronary risk factors.

The effects of cardiac denervation on the hemodynamic responses to isometric handgrip contraction were studied in patients 1--5 years after allograft cardiac transplantation. The objective of these studies was to determine the role of cardioacceleration and myocardial contractility on the increase in systemic arterial pressure during isometric exercise. Initially, noninvasive measurement of brachial artery pressure and heart rate during 60 seconds of isometric exercise at 50% of maximal voluntary contraction (50% MVC) were recorded in 23 cardiac transplant patients, 18 ischemic heart disease patients, and 15 healthy controls. While the increases in arterial pressure were not significantly different among the three groups and the heart rate response for the healthy controls and ischemic heart disease patients were similar, the transplant patient's heart rate remained essentially unchanged. In an attempt to determine the mechanisms for the increase in arterial pressure, despite any increase in heart rate in transplant patients, we recorded left ventricular volumes before and at the end of 50% MVC using fluoroscopy of tantalum midwall myocardial markers in seven cardiac transplant recipients and seven nontransplant cardiac surgery patients. The rise in arterial pressure during isometric exercise in both groups of patients resulted from a significant increase in peripheral vascular resistance but not in stroke volume or cardiac output. These data demonstrate that the rise in arterial pressure observed during isometric exercise can be achieved by increased peripheral vascular resistance alone in patients who lack the capacity to increase heart rate or stroke volume.