Eric T. Poehlman

Changes in energy balance and body composition at menopause: a controlled longitudinal study.

THIS ARTICLE HAS BEEN RETRACTED Menopause heralds the onset of physiologic changes that increase the risk for cardiovascular disease [1-3]. Although many women report increased body weight during menopause, no longitudinal studies have examined energy intake and energy expenditure and their association with changes in body composition and fat distribution. Several cross-sectional studies have suggested that decreases in resting metabolic rate and physical activity may be accelerated in the postmenopausal years [4-6]. The decrease in energy expenditure during rest and physical activity may be related to the decreased fat-free mass that has been seen in postmenopausal women [7-9]. More-over, the decrease in energy expenditure may result in increased fat mass if daily energy intake is not reduced accordingly. Other researchers, however, have not found that menopause independently affects body weight gain [10, 11]. These studies [4-11] have provided incomplete information on menopause-related changes in energy expenditure and body composition. Cross-sectional designs do not allow a robust examination of the effects of menopause on metabolic and cardiovascular risk factors, and no longitudinal studies have included measures of resting metabolic rate and body composition. To this end, we compared longitudinal changes in resting metabolic rate, body composition, and physical activity in a cohort of healthy premenopausal women who experienced menopause with changes in these variables in a cohort of women who remained premenopausal. Methods THIS ARTICLE HAS BEEN RETRACTED Patients Thirty-eight healthy, nonsmoking, premenopausal white women (age range, 44 to 48 years) were tested for baseline metabolic characteristics. Women were recruited from the surrounding communities through advertisements in the local newspaper and radio and were then screened by a telephone interview. None had coronary heart disease (for example, ST-segment depression greater than 1 mm at rest or during a modified Balke exercise test), cardiomyopathy, or hypertension (resting blood pressure greater than 140/90 mm Hg); were receiving medications that could affect cardiovascular function or metabolic rate; or had a medical history of diabetes. All premenopausal women were tested between days 5 and 12 of the follicular phase of their menstrual cycle. Menopause status was determined by interview. Six years later, patients participated in an identical series of metabolic tests, for which identical testing equipment was used. The reproducibility of the metabolic tests over this time period has previously been reported [5]. After follow-up, 18 women had spontaneously stopped menstruating for at least 12 months (2 1 years after menopause began), and 17 reported normal menstrual function. We excluded three perimenopausal women from the analyses. None of the women had received hormone replacement therapy. The Committee on Human Research for the Medical Sciences approved the study, and each volunteer provided written informed consent before the study began. Timing and Description of Metabolic Tests The study methods have been previously described [4]. Briefly, resting metabolic rate was measured for 45 minutes on the morning (0730 hours) after a 12-hour overnight fast. Each volunteer was placed in a supine position, and a clear plastic hood was placed over her head. Room air was continuously drawn through the hood, and the flow rate was measured by a pneumotachograph. Oxygen consumption (Vo 2) and CO2 production were continuously measured and analyzed during this period and were converted to a caloric equivalent (kcal/d) [12]. Peak Vo 2 was assessed by a progressive, symptom-limited treadmill exercise test. Body fat was estimated from body density by underwater weighing [13], and fat-free mass was calculated as total body mass minus fat mass. Waists were measured at the minimal circumference between the xiphoid process and the superior anterior iliac crest, and hips were measured at the maximal protrusion of the buttocks. The physical activity level during leisure time was measured using a structured interview [14]. Plasma glucose levels were determined using a YSI glucose analyzer (Yellow Springs Instruments, Yellow Springs, Ohio). Plasma immunoreactive insulin levels were determined by radioimmunoassay. Food intake was measured from 3-day food intake diaries (2 weekdays and 1 weekend day). We used a Student t-test to compare changes in the outcome measures between baseline and the end of follow-up within each subgroup. Values are expressed as the mean SD. Results THIS ARTICLE HAS BEEN RETRACTED Baseline physical characteristics of the cohort of premenopausal women are shown in Table 1. No differences were seen between the baseline characteristics of women who experienced natural menopause and those of women who remained premenopausal (Table 1). When women were retested after 6 years of follow-up, 18 were classified as postmenopausal and 17 remained premenopausal. Although total body weight did not differ between groups after follow-up, the composition of body weight showed distinct differences. Postmenopausal women lost more fat-free mass and gained more fat mass than women who remained premenopausal (Table 1). Women who experienced natural menopause had a greater decrease in resting metabolic rate and physical activity during leisure time. Fasting insulin levels and the waist-to-hip ratio were also increased more in women who became postmenopausal. Menopause did not affect body weight, fasting glucose levels, energy intake, or peak Vo 2. Table 1. Longitudinal Changes in Women Who Experienced Menopause (n = 18) and in Women Who Remained Premenopausal (n = 17)* Discussion THIS ARTICLE HAS BEEN RETRACTED Women in the United States now live an average of 75 to 80 years [15]. Those who experience menopause can expect to live approximately 30 years beyond this natural event, a time period that is approximately equivalent to their reproductive life span. The onset of menopause may be a risk factor for cardiovascular disease in women [1-3]. We used a longitudinal design to compare cardiovascular and metabolic changes in women who spontaneously stopped menstruating with changes in age-matched women who remained premenopausal. Women who stopped menstruating had distinct changes in energy expenditure during rest and physical activity, body composition, and fat distribution that could increase the risk for cardiovascular and metabolic disorders. Although our study could not establish cause and effect, our results suggest that natural menopause is associated with a worsening cardiovascular and metabolic risk profile. Resting metabolic rate, the largest component of daily energy expenditure, regulates body weight, body composition, and daily energy needs [16]. Resting metabolic rate decreases with age in women, a process that is associated with the loss of fat-free mass [4]; however, the degree to which normal menopause accelerates this decrease is unclear. Cross-sectional data suggest that the decrease in resting metabolic rate and fat-free mass may be accelerated in postmenopausal women not receiving hormone replacement therapy [4, 17]. However, few previous longitudinal studies have been done on the effect of menopause on metabolic rate and body composition. In our study, fat-free mass decreased by 3 kg and resting metabolic rate declined by approximately 100 kcal/d in postmenopausal women; no marked changes were noted in women who remained premenopausal. Thus, it is likely that resting energy requirements are lower in postmenopausal women because of the associated loss of metabolically active tissue. We used a peak Vo 2 test to evaluate cardiovascular fitness and used an activity questionnaire to assess physical activity during leisure time. Postmenopausal women reported lower levels of leisure time physical activity than did premenopausal women, despite a similar decrease in peak Vo 2 in both groups. The decline in physical activity during leisure time may have been related to the increase in body fat and decline in fat-free mass seen in postmenopausal women. Although Wing and colleagues [11] did not measure body composition, they found greater weight gain in women who reported the largest decline in exercise-related behaviors over 3 years. Taken together, the decline in energy expenditure during rest and leisure (approximately 230 kcal/d), without a proportional reduction in energy intake, supports a period of positive energy imbalance that may be related to the increased fat mass seen in women who became postmenopausal. Cross-sectional studies have reported discrepant results on the independent effects of menopause on body fat and fat distribution. Some investigators found an accelerated accumulation of fat in the intra-abdominal region [8, 9], whereas others found no independent menopause-related effect [17]. Our results support an increase in total body fat, which, as evidenced by the increase in the waist-to-hip ratio, is probably stored in central regions of the body. An increase in central body fat increases the risk for many chronic disorders, including atherosclerosis, hypertension, hypercholesterolemia, and insulin resistance [18]. Fasting insulin levels increased in women who experienced menopause, a finding consistent with those of previous longitudinal investigations [3]. This increased insulin level could be predicted because increased levels of total and intra-abdominal body fat are associated with higher levels of fasting insulin [17]. Our findings cannot establish cause and effect and cannot be extrapolated to other racial and ethnic groups. Larger sample sizes consisting of women receiving and not receiving hormone replacement therapy are needed to confirm and extend our preliminary observations regarding the energy imbalance of menopause and the possible therapeutic benefits of hormone replacement. Nevertheless, our longitudinal findings sugge

Effect of menopausal status on body composition and abdominal fat distribution.

OBJECTIVE: Preliminary studies suggest that the menopause transition is associated with deleterious changes in body composition and abdominal fat distribution. Limitations of the methodology used in these studies, however, render their conclusions controversial. Thus, the present study used radiologic imaging techniques to examine the effect of menopausal status on body composition and abdominal fat distribution.DESIGN: Cross-sectional.SUBJECTS: Fifty-three healthy, middle-aged, premenopausal women (mean±SD; 47±3 y) and 28 early-postmenopausal women (51±4 y).MEASUREMENTS: Total and regional body composition by dual energy X-ray absorptiometry and abdominal fat distribution by computed tomography.RESULTS: No differences in total body fat-free mass or appendicular skeletal muscle mass were noted between groups. In contrast, total body fat mass was 28% higher (23±7 vs 18±7 kg) and percentage fat 17% higher (35±6 vs 30±9%; both P<0.01) in postmenopausal women compared with premenopausal women. Postmenopausal women had a 49% greater intra-abdominal (88±32 vs 59±32 cm2; P<0.01) and a 22% greater abdominal subcutaneous fat area (277±93 vs 227±108 cm2; P<0.05) compared to premenopausal women. The menopause-related difference in intra-abdominal fat persisted (P<0.05) after statistical adjustment for age and total body fat mass, whereas no difference in abdominal subcutaneous fat was noted. A similar pattern of differences in total and abdominal adiposity was noted in sub-samples of pre- and postmenopausal women matched for age or fat mass.CONCLUSION: Our data suggest that early-postmenopausal status is associated with a preferential increase in intra-abdominal fat that is independent of age and total body fat mass.

Total energy expenditure and energy requirements in healthy elderly persons

To investigate energy requirements in healthy elderly subjects, we assessed the association of total energy expenditure (TEE) with resting metabolic rate (RMR), physical activity, body composition, and energy intake in 13 individuals (aged 56 to 78 years, six women and seven men). Free-living TEE was measured using doubly labeled water, RMR was measured by respiratory gas analysis, and energy expenditure of physical activity (EEPA) was derived from the difference between TEE and RMR, assuming the thermic response to feeding contributes 10% of TEE. Fat mass (FM) and fat-free mass (FFM) were obtained from underwater weighing, VO2max was determined from a bicycle test to exhaustion, energy intake was obtained from a 3-day food diary, and leisure time activity (LTA) was determined by structured interview. TEE was 2,406 +/- 438 kcal/d (range, 1,856 to 3,200 kcal/d, or 1.25 to 2.11 times RMR) and was related to VO2max (r = .79, P = .001), LTA (r = .74, P = .004), FFM (r = .69, P = .009), and FM (r = -.64, P = .018). The association between TEE and VO2max persisted after adjustment for FFM (partial r = .58, P = .036). EEPA was related to LTA (r = .83, P less than .0001) and FM (r = -.58, P = .039). Energy intake underestimated TEE by 31% +/- 18% in women and by 12% +/- 11% in men. Using stepwise regression, TEE was best predicted by VO2max and LTA (total adjusted r2 = .86). We conclude the following: (1) TEE varies greatly within healthy elderly subjects due to variations in physical activity; (2) VO2max has an important role in predicting energy requirements in older individuals; and (3) healthy older individuals underreport energy intake.

Menopause‐Related Changes in Body Fat Distribution

Abstract: Menopause‐related changes in body fat distribution may partially explain the greater risk of cardiovascular and metabolic disease during the postmenopausal years. To date, however, the effect of the menopause transition on body fat distribution remains unclear. Cross‐sectional and longitudinal studies using waist circumference or the waist‐to‐hip ratio show no effect of menopause on body fat distribution. By contrast, studies using dual‐energy X‐ray absorptiometry showed increased trunk fat in postmenopausal women. Moreover, studies using computed tomography (CT) and magnetic resonance imaging (MRI) show that postmenopausal women have greater amounts of intra‐abdominal fat compared to premenopausal women. Collectively, these studies suggest that the menopause transition is associated with an accumulation of central fat and, in particular, intra‐abdominal fat. Whether menopause‐related differences in trunk or intra‐abdominal fat are independent of age and/or adiposity, however, is unclear. Thus, we recently examined the effect of menopausal status on body composition and abdominal fat distribution in 53 middle‐aged, premenopausal women (47 ± 3 years) and 28 early postmenopausal women (51 ± 4 years). Postmenopausal women had 36% more trunk fat (p < 0.01), 49% greater intra‐abdominal fat area (p < 0.01), and 22% greater subcutaneous abdominal fat area (p < 0.05) than premenopausal women. The menopause‐related difference in intra‐abdominal fat persisted (p < 0.05) after statistical adjustment for age and fat mass, whereas no differences were noted in trunk or abdominal subcutaneous fat. A similar pattern of differences in trunk, subcutaneous, and intra‐abdominal fat was observed in subsamples of pre‐ and postmenopausal women matched for age or fat mass. Our data and that of others suggest that early postmenopausal status is associated with a preferential increase in intra‐abdominal fat that is independent of age and total adiposity. Thus, CT and MRI should be used when examining menopause‐related changes in body fat distribution.

Increased Resting Metabolic Rate in Patients with Congestive Heart Failure

Cardiac cachexia, which is characterized by a negative energy balance and subsequent weight loss and systemic wasting, occurs frequently in patients with end-stage heart failure [1]. It is unclear whether reduction in caloric intake or elevated caloric expenditure causes this condition. We know of no recent studies that have systematically investigated resting metabolic rate and body composition in patients with heart failure and documented systolic dysfunction. Thus, we investigated a cohort of patients with heart failure, using indirect calorimetry to measure resting metabolic rate, dual energy x-ray absorptiometry to measure body composition, and food diaries to measure caloric intake. We then compared the results with those from an age-matched cohort of healthy volunteers. Methods Patients Twenty patients with documented dyspnea and fatigue during ordinary physical activity were recruited by the Heart Failure Service at the Baltimore Veterans Affairs Medical Center. Patients were male (7 were black and 13 were white), and each had a mean left ventricular ejection fraction (SD) by radionuclide ventriculography of 0.24 0.10 (range, 0.06 to 0.40). Mean time (SD) since diagnosis was 45 36 months. Patients were taking two or more of the following medications: diuretics, digoxin, and vasodilators (angiotensin-converting enzyme inhibitors or hydralazine-nitrates). Symptoms were stable, patients were in New York Heart Association functional class II (n = 2), III (n = 14), or IV [n = 4], and no concomitant acute disease was present. Forty healthy, age-matched male volunteers served as controls. Reasons for excluding volunteers from the control cohort included 1) cardiomyopathy or clinical evidence of coronary heart disease, such as ST-segment depression 1 mm at rest or exercise; 2) hypertension with resting blood pressure greater than 140/90 mm Hg; and 3) noncardiac disease that limited exercise performance, such as arthritis, peripheral vascular disease, and cerebral vascular disease. This study was approved by the Committee on Human Research at the University of Maryland, and written informed consent was obtained from each patient and control before the investigation. Timing of Tests Methods for the timing of tests have been previously described [2]. At approximately 8:30 a.m., after patients and controls had completed a 12-hour fast in a darkened, temperature-controlled room, their resting metabolic rates were measured for 45 minutes. Each patient or control was placed in a supine position with a clear plastic hood over his head. Room air was continuously drawn through the hood and the flow rate was measured by a pneumotachograph. Oxygen consumption and carbon dioxide production were continuously measured and analyzed and converted to a caloric equivalent (kcal/d) using the Weir equation [3]. Daily caloric intake and daily macronutrient intake were estimated from a 3-day (2 weekdays and 1 weekend day) food diary. Fat-free mass and fat mass were measured using a total body scan with dual-energy x-ray absorptiometry (Model DPX-L, Lunar Radiation Corp., Madison, Wisconsin). Peak oxygen consumption (Vo 2) was assessed by a progressive, symptom-limited treadmill exercise test in which the speed of the treadmill was constant and the incline was increased by 2% every 2 minutes. Statistical Analysis The physical characteristics of cohorts and patients with heart failure were compared using unpaired t-tests. The relation between variables was measured by linear regression analysis. A one-way analysis of covariance examined whether resting metabolic rate differed between controls and patients with heart failure after we statistically controlled for differences in fat-free mass. Values are expressed as mean SD. Results Because no differences were noted between black and white patients, data for all patients were pooled. No differences in age or body weight existed between controls and patients with heart failure Table 1, but because patients with heart failure were shorter than controls (P = 0.08), the body mass index in patients with heart failure was higher than it was in controls (P < 0.05). Fat-free mass tended to be lower in patients with heart failure (P = 0.09), but no difference in fat mass existed. Predictably, peak Vo 2 was lower (P < 0.01) in patients with heart failure. No difference was noted in daily caloric intake between groups. Table 1. Physical Characteristics in Healthy Men and Patients with Congestive Heart Failure* Measured resting metabolic rate (kcal/d) was 18% higher in patients with heart failure (mean, 1828 275 kcal/d [95% CI, 1289 to 2367 kcal/d]) than in controls (1543 219 kcal/d [95% CI, 1114 to 1972 kcal/d]; P < 0.01). Resting metabolic rate correlated with fat-free mass in both groups (Figure 1). When statistically adjusted for differences in fat-free mass, the mean difference in resting metabolic rate between patients with heart failure (1875 178 kcal/d) and controls (1521 171 kcal/d) was magnified. Figure 1. Relation between resting metabolic rate (kcal/d) and fat-free mass in patients with heart failure and controls. Discussion The higher resting metabolic rate in patients with heart failure probably contributes to weight loss and musculoskeletal wasting. The difference in resting metabolic rate between elderly patients with heart failure and healthy elderly persons is clinically significant (18%; 283 kcal/d). When resting metabolic rate data for each group were compared after being normalized for differences in fat-free mass, the higher resting metabolic rate in patients with heart failure compared with that in healthy elderly persons was even more striking ( 354 kcal/d). These data highlight the importance of factors other than simple reduction in caloric intake that contribute to weight loss, which complicates the course of many patients with late-stage heart failure. It is unlikely that abnormalities in the two other components of daily caloric expenditure contribute substantially to weight loss in patients with heart failure; that is, the caloric expenditure associated with meal consumption constitutes only 10% of daily caloric expenditure [4], and the deconditioned state of patients with heart failure diminishes the possibility that a high level of caloric expenditure associated with physical activity is an important factor. A voluntary reduction in caloric intake is commonly thought to contribute to the weight loss of patients with heart failure [1], but we found no difference in reported daily caloric intake between patients with heart failure and controls. However, it should be acknowledged that difficulties and inaccuracies associated with reporting of food intake exist [5]. Resting metabolic rate is frequently used to establish daily caloric requirements in both healthy and diseased elderly persons [6]. Data from our study suggest that such guidelines, if based on the caloric requirements of healthy persons, would be inappropriate for patients with heart failure. Using recent equations generated from a healthy elderly cohort in our laboratory would underestimate resting metabolic rate in patients with heart failure by 270 kcal per day (measured, 1828 kcal/d; predicted, 1556 kcal/d) [7]. The mechanism for the higher resting metabolic rate in patients with heart failure is unknown. Increased myocardial oxygen requirements and the increased metabolic cost of breathing may contribute [1], but it is probable that systemic factors are also important. Circulating levels of tumor necrosis factor are higher in patients with heart failure [8], but the relation of this to resting metabolic rate is unknown. A more likely explanation is elevated sympathetic nervous system activity, which is typically seen in patients with heart failure, especially heart failure in its advanced stages [9]. We have shown that resting metabolic rate increases in relation to increments in the rate of norepinephrine appearance into circulation [2]. Thus, it is likely that overactivity of the sympathetic nervous system is involved in the pathogenesis of the higher resting metabolic rate in patients with heart failure. Future studies in patients with heart failure should address this important hypothesis. A higher resting metabolic rate in patients with heart failure may at least partially account for otherwise unexplained weight loss. Present caloric guidelines established in healthy elderly persons significantly underestimate the resting caloric needs of elderly patients with heart failure. Proper nutritional and physical activity interventions could reverse or prevent weight loss in patients with heart failure, improve their functional capacity and body composition, and possibly alter the long-term evolution of cardiac dysfunction.

A review: exercise and its influence on resting energy metabolism in man.

Daily energy expenditure is composed of three major components: 1) resting metabolic rate (RMR); 2) the thermic effect of feeding (TEF); and 3) the thermic effect of activity (TEA). RMR constitutes 60 to 75% of daily energy expenditure and is the energy associated with the maintenance of major body functions. TEF is the cumulative increase in energy expenditure after several meals and constitutes approximately 10% of daily energy expenditure. Most investigators, however, have examined the thermic effect of a single meal test (TEM). TEA is the most variable component of daily energy expenditure and can constitute 15 to 30% of 24-h energy expenditure. This component includes energy expenditure due to physical work, muscular activity, including shivering and fidgeting, as well as purposeful physical exercise. Participation in purposeful exercise (both acute and chronic) is a subcomponent of TEA and has been found to influence resting energy expenditure (RMR and TEM). Reports in the literature, however, are discrepant regarding the direction and magnitude of the effects of exercise and exercise training on RMR and TEM. Cross-sectional and longitudinal studies that have examined the effects of exercise on RMR and TEM are reviewed. Possible explanations for divergent results in the literature are discussed. The major focus of this review is directed to human studies, although pertinent animal work is included. The role of genetic variation, gender specific responses, and methodological considerations for future studies examining the relation among RMR, TEA, and TEM are considered. Although still controversial, purposeful physical exercise appears to influence resting energy expenditure in man.

Menopause, central body fatness, and insulin resistance: effects of hormone-replacement therapy.

In addition to being associated with termination of reproductive life in women, the menopause coincides with an increase in several comorbidities including cardiovascular disease. This increase in the prevalence of cardiovascular disease in the postmenopausal years has been partially attributed to adverse effects of estrogen deficiency on plasma lipid-lipoprotein levels and on the cardiovascular system, although other factors are contributing. Central body fatness and insulin resistance are components of a cluster of metabolic abnormalities which also increases the risk of cardiovascular disease. This review summarizes studies that have examined the effects of the menopause transition and of estrogen-replacement therapy on central body fatness and insulin resistance. Review of cross-sectional studies suggests that the menopause transition is associated with an increase in abdominal and visceral adipose tissue accumulation, as measured either with dual X-ray absorptiometry or computed tomography. These results appear to be independent of the aging process and total body fatness. In general, cross-sectional studies using circumference measurements did not find any significant effect of the menopause. Longitudinal studies also support that accumulation of central body fatness accelerates with menopause. The effects of the menopause on insulin resistance appear to be moderate, if any, although available studies are clearly insufficient to draw firm conclusions. The majority of interventional studies support the notion that hormone-replacement therapy attenuates the accumulation of central fat in postmenopausal women, compared with control or placebo-treated women. Retrospective comparisons of hormone users and nonusers also support a protective effect of hormone replacement on fat distribution. Moderate effects of estrogen therapy were found on insulin resistance in postmenopausal women, although long-term, controlled trials using accurate measurements of insulin sensitivity are lacking. Treatment with progestins exerts moderate deleterious effects on insulin sensitivity, which may be attributable to the partial androgenicity of progestins used. It is concluded that part of the increased incidence of cardiovascular disease in postmenopausal women may be attributable to increased central body fatness. Therapies aiming at preventing these changes in fat distribution such as hormone-replacement therapy, diet or exercise are likely to provide long-term cardiovascular and metabolic benefits for womens health. Coronary Artery Dis 9:503–511

Skeletal Muscle and Cardiovascular Adaptations to Exercise Conditioning in Older Coronary Patients

BACKGROUND Older coronary patients suffer from a low functional capacity and high rates of disability. Supervised exercise programs improve aerobic capacity in middle-aged coronary patients by improving both cardiac output and peripheral extraction of oxygen. Physiological adaptations to aerobic conditioning, however, have not been well studied in older coronary patients. METHODS AND RESULTS The effect of a 3-month and a 1-year program of intense aerobic exercise was studied in 60 older coronary patients (mean age, 68 +/- 5 years) beginning 8 +/- 5 weeks after myocardial infarction or coronary bypass surgery. Outcome measures included peak aerobic capacity, cardiac output, arterio-venous oxygen difference, hyperemic calf blood flow, and skeletal muscle fiber morphometry, oxidative enzyme activity, and capillarity. Training results were compared with a sedentary, age- and diagnosis-matched control group (n = 10). Peak aerobic capacity increased in the intervention group at 3 months and at 1 year by 16% and 20%, respectively (both P < .01). Peak exercise cardiac output, hyperemic calf blood flow, and vascular conductance were unaffected by the conditioning protocol. At 3 and 12 months, arteriovenous oxygen difference at peak exercise was increased in the exercise group but not in control subjects. Histochemical analysis of skeletal muscle documented a 34% increase in capillary density and a 23% increase in succinate dehydrogenase activity after 3 months of conditioning (both P < .02). At 12 months, individual fiber area increased by 29% compared with baseline (P < .01). CONCLUSIONS Older coronary patients successfully improve peak aerobic capacity after 3 and 12 months of supervised aerobic conditioning compared with control subjects. The mechanism of the increase in peak aerobic capacity is associated almost exclusively with peripheral skeletal muscle adaptations, with no discernible improvements in cardiac output or calf blood flow.

Free-living daily energy expenditure in patients with Parkinson's disease.

Previous studies have suggested that elevated resting energy expenditure contributes to weight loss in patients with Parkinsons disease (PD).Body weight is, however, ultimately determined by variation in daily energy expenditure and not just resting energy expenditure. Therefore, we examined the hypothesis that PD patients are characterized by elevated daily energy expenditure. Sixteen patients with levodopa responsive PD and 46 healthy elderly controls were characterized for daily energy expenditure and its components (resting and physical activity energy expenditure) using a combination of the doubly labeled water technique (over 10 days) and resting indirect calorimetry. Fat-free mass and fat mass were measured by dual energy x-ray absorptiometry. Results showed that fat mass and fat-free mass did not differ between groups. Daily energy expenditure was 15% lower (2214 +/- 460 vs. 2590 +/- 497 kcal/d; p < 0.01) in PD patients compared to controls. This was primarily due to lower physical activity energy expenditure (339 +/- 366 vs. 769 +/- 412 kcal/d; P < 0.01) in PD patients as resting energy expenditure was not different between groups (1655 +/- 283 vs. 1561 +/- 219 kcal/d). These results show that daily energy expenditure is lower in PD patients compared to healthy elderly, primarily due to reduced physical activity energy expenditure. These results argue against the hypothesis that an abnormally elevated daily energy expenditure contributes to weight loss in PD. NEUROLOGY 1997;48: 88-91

Resistance training on physical performance in disabled older female cardiac patients

PURPOSE We evaluated the value of resistance training on measures of physical performance in disabled older women with coronary heart disease (CHD). METHODS The study intervention consisted of a 6-month program of resistance training in a randomized controlled trial format. Training intensity was at 80% of the single-repetition maximal lift. Control patients performed light yoga and breathing exercises. Study participants included 42 women with CHD, all >or= 65 yr of age and community dwelling. Subjects were screened by questionnaire to have low self-reported physical function. The primary study measurements related to the performance of 16 household activities of the Continuous Scale Physical Functional Performance test (CSPFP). These ranged from dressing, to kitchen and cleaning activities, to carrying groceries and walking onto a bus with luggage, and a 6-min walk. Activities were measured in time to complete a task, weight carried during a task, or distance walked. Other measures included body composition, measures of aerobic fitness and strength, and questionnaire-based measures of physical function and depression score. RESULTS Study groups were similar at baseline by age, aerobic capacity, strength, body composition, and in performing the CSPFP. After conditioning, 13 of 16 measured activities were performed more rapidly, or with increased weight carried, compared with the control group (all P < 0.05). Maximal power for activities that involved weight-bearing over a distance, increased by 40% (P < 0.05). CONCLUSIONS Disabled older women with CHD who participate in an intense resistance-training program improve physical capacity over a wide range of household physical activities. Benefits extend beyond strength-related activities, as endurance, balance, coordination, and flexibility all improved. Strength training should be considered an important component in the rehabilitation of older women with CHD.