Mean Physical Activity Level Research Articles

Energy expenditure does not predict weight change in either Nigerian or African American women

BackgroundThe relation between variation in interindividual levels of energy expenditure and weight gain remains controversial. ObjectiveTo determine whether or not components of the energy budget predict weight change, we conducted an international comparative study in 2 cohorts of women from sociocultural environments that give rise to the extremes of obesity prevalence. DesignThis was a prospective study with energy expenditure measured at baseline and weight measured annually for 3 y. Participants included 149 women from rural Nigeria and 172 African American women. The energy budget was determined by using respiratory gas exchange and doubly labeled water. Main outcomes included total, resting, and activity energy expenditure and physical activity level (ie, total energy expenditure/resting energy expenditure); baseline anthropometric measures; and annual weight change. ResultsMean body mass index (in kg/m2) was 23 among the Nigerians and 31 among the African Americans; the prevalences of obesity were 7% and 50%, respectively. After adjustment for body size, no differences in mean activity energy expenditure or physical activity level were observed between the 2 cohorts. In addition, in a mixed-effects, random-coefficient model, interindividual variation in activity energy expenditure at baseline was unrelated to the subsequent pattern of weight change. ConclusionsThese data suggest that interindividual levels of energy expended during activity do not have a large influence on age-related trends in adiposity. In addition, contrary to expectations, these data suggest that mean activity energy expenditure does not vary substantially between contemporary social groups with low and high prevalences of obesity.

Rates and Determinants of Uptake and Use of an Internet Physical Activity and Weight Management Program in Office and Manufacturing Work Sites in England: Cohort Study

Background Internet-based physical activity (PA) and weight management programs have the potential to improve employees’ health in large occupational health settings. To be successful, the program must engage a wide range of employees, especially those at risk of weight gain or ill health.Objective The aim of the study was to assess the use and nonuse (user attrition) of a Web-based and monitoring device–based PA and weight management program in a range of employees and to determine if engagement with the program was related to the employees’ baseline characteristics or measured outcomes.MethodsLongitudinal observational study of a cohort of employees having access to the MiLife Web-based automated behavior change system. Employees were recruited from manufacturing and office sites in the North West and the South of England. Baseline health data were collected, and participants were given devices to monitor their weight and PA via data upload to the website. Website use, PA, and weight data were collected throughout the 12-week program.Results Overall, 12% of employees at the four sites (265/2302) agreed to participate in the program, with 130 men (49%) and 135 women (51%), and of these, 233 went on to start the program. During the program, the dropout rate was 5% (11/233). Of the remaining 222 Web program users, 173 (78%) were using the program at the end of the 12 weeks, with 69% (153/222) continuing after this period. Engagement with the program varied by site but was not significantly different between the office and factory sites. During the first 2 weeks, participants used the website, on average, 6 times per week, suggesting an initial learning period after which the frequency of website log-in was typically 2 visits per week and 7 minutes per visit. Employees who uploaded weight data had a significant reduction in weight (−2.6 kg, SD 3.2, P< .001). The reduction in weight was largest for employees using the program’s weight loss mode (−3.4 kg, SD 3.5). Mean PA level recorded throughout the program was 173 minutes (SE 12.8) of moderate/high intensity PA per week. Website interaction time was higher and attrition rates were lower (OR 1.38, P= .03) in those individuals with the greatest weight loss.Conclusions This Web-based PA and weight management program showed high levels of engagement across a wide range of employees, including overweight or obese workers, shift workers, and those who do not work with computers. Weight loss was observed at both office and manufacturing sites. The use of monitoring devices to capture and send data to the automated Web-based coaching program may have influenced the high levels of engagement observed in this study. When combined with objective monitoring devices for PA and weight, both use of the website and outcomes can be tracked, allowing the online coaching program to become more personalized to the individual.

The Childcare Environment and Children’s Physical Activity

With increased numbers of children attending child care, this setting presents an ideal opportunity to promote physical activity and the early development of healthy behaviors. The purpose of this study was to examine the relationships between the childcare environment and physical activity behavior of preschool children. Aspects of the environment hypothesized to influence children's physical activity were assessed in 20 childcare centers using the Environment and Policy Assessment and Observation (EPAO) instrument. Physical activity behavior was assessed over 2 days using direct observation. Children in centers with supportive environments achieved more moderate-to-vigorous physical activity (15% of observations vs 9%; effect size [ES]=1.17), spent less time in sedentary activities (50% vs 61%; ES=-1.52), and had higher mean physical activity levels (2.68 vs 2.43; ES=1.41) compared to centers with less supportive environments. Facets of the physical and social environment related to physical activity behavior included active opportunities, portable play equipment, fixed play equipment, sedentary environment, and physical activity training and education. Previous research indicates that the childcare center that children attend significantly affects physical activity behavior. The current findings extend this evidence by identifying aspects of the childcare environment that relate to the physical activity behavior of children. These factors should be considered when identifying determinants of physical activity and designing interventions.

Bone Mineral Density in Children Exposed to Chronic Glucocorticoid Therapy

The objective of this study was to determine the impact of glucocorticoid exposure on lumbar spine bone mineral density (BMD) in children while concurrently measuring their calcium intake, serum 25-OH vitamin D levels, and physical activity. Forty-three patients (4-18 years) with renal glomerular diseases, dermatomyositis, inflammatory bowel disease, juvenile rheumatoid arthritis, post-solid organ transplant, and Duchenne muscular dystrophy were studied. All received at least 5 mg per day of prednisone for more than 6 months. The mean BMD z score was 0 +/- 0.2 (range, -3.8 to +3.3) with 2 patients (5%) having z scores less than -2. The mean daily calcium intake was 1147 +/- 145 g, with 1 patient having hypovitaminosis D (<15 ng/mL). The mean physical activity level was 7.8 +/- 0.8 h/wk. The small reductions in BMD observed in our population suggest that screening is likely not warranted in all children with chronic glucocorticoid exposure.

How Much More Sedentary Are Depressed Women Than Emotionally Healthy Women?

It is generally believed that women who are depressed are less active than their counterparts. Yet, few studies have objectively quantified this relationship. PURPOSE: To examine the relationship between objectively measured physical activity (PA) and depression in women. A secondary purpose was to quantify the difference in measured PA between depressed women and their counterparts. METHODS: In a cross-sectional study, 276 middle-aged women (age: 40±3 yr) wore MTI (formerly CSA) accelerometers for 7 consecutive days to measure PA. Total activity counts over the week were used to index PA. In addition, each subject completed the General Well-being Schedule (GWB), developed by the National Center for Health Statistics, to evaluate psychological distress and depression. Subjects were divided into quartiles based on their GWB scores and the middle two quartiles were combined, forming three total groups (relatively depressed, average, and positive well-being). Categories were also developed based on GWB scores so that clinically depressed women (n=46) could be compared to average women and those with positive mental health. RESULTS: Means (± SD) were calculated for PA (2.7±0.8 million counts), GWB scores (72.1±16.4), weight (66.1±10.1 kg), and BMI (23.8±3.4 kg/m2). Mean PA levels differed significantly across the GWB groups (F=3.8, p=0.05). Specifically, relatively depressed women (n=70) had the lowest PA (2.57±0.75 million counts) followed by the average (n=136) women (2.72±0.77 million counts), with the emotionally healthiest women (n=70) showing the highest levels of PA (2.86±0.87 million counts). When compared to the relatively depressed (lowest quartile), women in the positive well-being group were found to engage in about 70 minutes per week more physical activity, equivalent to brisk walking. When depression was denned clinically, rather than as the lowest quartile, the relation between GWB and PA was stronger (F=4.1, P=0.04), and the healthiest women were found to participate in about 85 more minutes of activity per week, equivalent to brisk walking, than the clinically depressed women. CONCLUSIONS: Women with high levels of PA are less likely to be depressed compared to women with low levels of PA. Additionally, women with positive mental health are much more physically active than depressed women.

Total energy expenditure (H218O), physical activity level and milk output of lactating rural Bangladeshi tea workers and nontea workers

To assess the total daily energy expenditure (TDEE), milk output and physical activity level (PAL) of chronically malnourished lactating women using the doubly labelled water method (DLW). Prospective, longitudinal study designed to assess the extent of malnutrition and energetics of lactating tea workers and nontea workers. North-east Bangladesh on women working and living in the same tea estates. Of an original cohort of 150 lactating women, 30 were selected to participate in this study when they were at about 12 months postpartum. One mother subsequently dropped out. On day 1 each women provided a urine sample, was administered a dose of DLW and 6 h later provided another sample. Further urine samples were collected for 21 subsequent days. In addition, every 5 days the mother provided a milk sample and at the same time her baby provided a urine sample. Mean (s.d.) BMI was 17.4 (1.63). Mean TDEE and PAL were significantly higher in workers than nonworkers (8.42 (1.38) and 6.83 (2.09) MJ/day, P = 0.02 and 1.92 (0.34) and 1.59 (0.44), P = 0.03, respectively). Mean milk output was similar in the two groups (672 (180) ml and 749 (189) ml in workers and nonworkers, respectively). Based on international BMI cutoffs, 79% of mothers were suffering from some degree of chronic energy deficiency. A total of 35% of workers and 17% of nonworkers were engaged in strenuous physical activity. The mean milk output of both workers and nonworkers was not different and was high especially as most of the mothers were about 12 months postpartum. No relationship was found between menses return and any of the variables studied. World Health Organization, Nestle Foundation, UNICEF.

Total energy expenditure and physical activity in young Scottish children: mixed longitudinal study

Childhood obesity has been attributed to a decline in total energy expenditure (TEE). We measured TEE, physical activity, and sedentary behaviour in a representative sample of young children from Glasgow, UK, at age 3 years (n=78), and we did a follow-up study at age 5 years (n=72). Mean physical activity level (TEE/resting energy expenditure) was 1.56 (SD 0.39) at age 3 years and 1.61 (0.22) at age 5 years. Median time in sedentary behaviour was 79% of monitored hours at age 3 years (IQR 74-84) and 76% (71-80) at age 5 years. Median time spent in moderate to vigorous physical activity represented only 2% of monitored hours at age 3 years (IQR 1-4) and 4% at age 5 years (2-6). Modern British children establish a sedentary lifestyle at an early age.

Physical activity and weight loss: does prescribing higher physical activity goals improve outcome?

Recommending increased physical activity facilitates long-term weight loss, but the optimal level of physical activity to recommend is unknown. The objective of the study was to evaluate the efficacy for long-term weight loss of recommendations for much higher physical activity than those normally used in behavioral treatments. Overweight men and women (n = 202) were randomly assigned to either a standard behavior therapy (SBT) for obesity, incorporating an energy expenditure (EE) goal of 1000 kcal/wk, or to a high physical activity (HPA) treatment, in which the goal was an EE of 2500 kcal/wk. To help HPA treatment group participants achieve this high exercise goal, their treatment included encouragement to recruit 1-3 exercise partners into the study, personal counseling from an exercise coach, and small monetary incentives. The HPA treatment group reported achieving higher mean (+/- SD) physical activity levels than did the SBT group at 6 mo (EE of 2399 +/- 1571 kcal/wk compared with 1837 +/- 1431 kcal/wk), 12 mo (EE of 2249 +/- 1751 kcal/wk compared with 1565 +/- 1309 kcal/wk), and 18 mo (EE of 2317 +/- 1854 kcal/wk compared with 1629 +/- 1483 kcal/wk) (all P < 0.01). Mean (+/- SEM) cumulative weight losses at 6, 12, and 18 mo in the HPA treatment group were 9.0 +/- 7.1, 8.5 +/- 7.9, and 6.7 +/- 8.1 kg, respectively. In the SBT group, the corresponding weight losses were 8.1 +/- 7.4, 6.1 +/- 8.8, and 4.1 +/- 7.3 kg, respectively. Between-group differences in weight loss were significant at 12 and 18 mo. These results suggest that recommendations of higher levels of physical activity (EE of 2500 kcal/wk) promote long-term weight loss better than do conventional recommendations.

Secular trends in acute myocardial infarction in relation to physical activity in the general Danish population.

Secular trends in AMI rates were analyzed in relation to physical activity levels. The population attributable risk of physical inactivity was calculated. Participants were randomly selected subjects from a suburb of Copenhagen, Denmark, screened during the years 1964-1991. Occupational physical activity and in leisure time were assessed 1964, 1974, 1976, 1982, 1987 and 1991 by self-administered questionnaire along with smoking habits and alcohol consumption. Blood pressure, weight, height and serum lipids were measured according to WHO-standards. Mortality data were obtained from death certificates, from hospital records or autopsies. Acute myocardial infarctions (AMI) 1964-1994 were included. 13.925 men and women aged 30, 40, 50 and 60 years, were drawn as random samples from a background population of 300.000 inhabitants. A cohort born in 1914 was examined in 1964 and 1974, a cohort born in 1936, was examined in 1976 and 1987; Monica (Monitoring trends and determinants in cardiovascular diseases) I cohort were examined in 1982 and 1987; MONICA II in 1986, and MONICA III in 1991. Mean physical activity level at leisure adjusted for age and sex increased over time (P < 0001). 25% of the men were sedentary, and more women reported a sedentary lifestyle than men. The overall trend was from 1964 to 1992 a decline in physical activity at work (P < 0001) in both gender and all age groups. The difference in AMI incidence rates between leisure time physical activity (LTPA) levels increased over time. No change was found in AMI rates comparing sedentary in different time periods. A remarkable decrease over time in the AMI incidence rate was found in physically active during leisure time. Population attributable risk (PAR) exceeded 40% in both genders in the late 1980s. In conclusion the difference in AMI rates between LTPA subgroups has increased over time. The low AMI rates observed among the most physically active reveal a substantial potential for the prevention of AMI through physical activity. A population attributable risk of more than 40% for physical inactivity suggests a potential for primary prevention through increased physical activity.

Energy balance in depleted ambulatory patients with chronic obstructive pulmonary disease: the effect of physical activity and oral nutritional supplementation.

Patients with chronic obstructive pulmonary disease (COPD) often suffer from weight loss. The aim of the present study was to gain insight into the energy balance of depleted ambulatory COPD patients, in relation to their habitual level of physical activity and consumption of oral nutritional supplements. Clinically stable and weight-stable patients (n 20; BMI 19.8+/- SD 2.0 kg/m2) were studied 1 and 3 months after rehabilitation or recovery in the clinic and were at random assigned to a control or intervention group with regard to nutritional supplementation. Energy intake was measured with a 7 d food record. Energy expenditure was estimated from a simultaneous 7 d assessment of physical activity with a tri-axial accelerometer for movement registration in combination with measured BMR. Body mass was measured at several time points. The body mass remained stable in both groups after 1 or 3 months and mean energy balances were comparable for both groups. The mean body-mass change between month 1 and 3 was negatively related to the mean physical activity level (r -0.49; P=0.03). Weight change over the 3 months was negatively associated with the physical activity level. These results suggest that knowledge about the individual physical activity level is necessary for the estimation of the energy need of the COPD patient.

Physical activity levels are low in free-living adults with chronic paraplegia.

To compare physical activity levels (PALs) of free-living adults with chronic paraplegia with World Health Organization recommendations and to compare energy expenditure between persons with complete vs. incomplete paraplegia. Twenty-seven euthyroid adults (17 men and 10 women) with paraplegia (12.5 +/- 9.5 years since onset; 17 with complete lesions and 10 with incomplete lesions) participated in this cross-sectional study. Resting metabolic rate was measured by indirect calorimetry and total daily energy expenditure (TDEE) by heart rate monitoring. PAL was calculated as TDEE/resting metabolic rate. Total body water was measured by deuterium dilution and fat-free mass (FFM) and fat mass (FM) by calculation (FFM = total body water/0.732; FM = weight - FFM). Obesity was defined using the following percentage FM cutoffs: men 18 to 40 years >22% and 41 to 60 years >25%; and women 18 to 40 years >35% and 41 to 60 years >38%. Nineteen subjects (70.4%; 13 men and six women) were obese. Fifteen subjects (56%) engaged in structured physical activity 1.46 +/- 0.85 times during the observation period for a mean of 49.4 +/- 31.0 minutes per session. Despite this, mean PAL of the group was 1.56 +/- 0.34, indicative of limited physical activity. TDEE was 24.6% lower in subjects with complete paraplegia (2072 +/- 505 vs. 2582 +/- 852 kcal/d, p = 0.0372). PAL of the group was low, indicating that persons with paraplegia need to engage in increased frequency, intensity, and/or duration of structured physical activity to achieve a PAL >/=1.75 and, thereby, to offset sedentary activities of daily living.

Energy requirements of women of reproductive age

The energy requirements of women have been based on total energy expenditure (TEE) derived from the factorial approach or as multiples of basal metabolic rate (BMR). This study was designed to reevaluate the energy requirements of healthy, moderately active underweight, normal-weight, and overweight women of reproductive age. The energy requirements of 116 women [n = 13 with a low body mass index (BMI), n = 70 with a normal BMI, and n = 33 with a high BMI] were estimated from TEE measured by the doubly labeled water method. Twenty-four-hour EE and BMR were measured by room respiration calorimetry, activity EE was estimated from nonbasal EE as TEE - BMR, and physical activity level was calculated as TEE/BMR. Body composition was derived from a multicomponent model. Fitness, strength, and physical activity level were assessed, and fasting serum indexes were measured. Energy requirements differed among the low-BMI (8.9 +/- 0.9 MJ/d), normal-BMI (10.1 +/- 1.4 MJ/d), and high-BMI (11.5 +/- 1.9 MJ/d) groups (P = 0.02-0.001, all pairwise comparisons). Major predictors of BMR, 24-h EE, and TEE were weight, height, and body composition; minor predictors were fasting metabolic profile and fitness. Fat-free mass and fat mass accounted for the differences in EE seen between the BMI groups. The mean physical activity level of 1.86 suggested that the multiples of BMR used to estimate energy requirements have been underestimated. Recommended energy intakes for healthy, moderately active women of reproductive age living in industrialized societies should be revised on the basis of TEE.

Physical activity and oxidative stress in the elderly

Aging is associated with a decline in the daily physical activity level. Regular physical activity is thought to be an important determinant of health and an active lifestyle might delay the age-associated decline in body function and thus enhance the quality of life of older adults. On the other hand, a high physical activity level might be associated with an increased production of reactive oxygen species (ROS). A state of increased levels of intracellular ROS production is referred to as oxidative stress. The relationship between oxidative stress and physical activity, however, is still poorly understood, particularly in advanced age, which could be attributed to methodological problems concerning the assessment of oxidative stress and the assessment of the physical activity level. Results are presented on the effects of imposed exercise training on physical activity and exercise-induced oxidative stress. It is concluded that (i) a training program of moderate intensity results in a decline of non-training physical activity; (ii) spending relatively more time on lowintensity activities negatively affects the mean physical activity level. Despite this, it is not necessary for elderly to participate in high-intensity, sporting activities in order to increase their physical activity level; (iii) oxidative stress occurs during cycling at submaximal intensity as measured by free radical mediated products of antipyrine; (iv) a training or antioxidant supplementation intervention has no effect on exercise-induced oxidative stress; (v) physically active elderly subjects have a reduced exercise-induced oxidative stress compared to elderly with a lower level of physical activity. Thus, regular physical activity improves the antioxidant defense capacity.

Physical activity in daily life in patients with chronic low back pain

Verbunt JA, Westerterp KR, van der Heijden GJ, Seelen HA, Vlaeyen JW, Knottnerus JA. Physical activity in daily life in patients with chronic low back pain. Arch Phys Med Rehabil 2001;82:726-30. Objectives: To evaluate disuse (ie, a decreased daily physical activity level) in patients with chronic low back pain (LBP) and to evaluate the construct validity of accelerometry for measuring physical activity in daily life. Design: Case-control study in a cross-sectional design; comparison of accelerometry to the criterion standard (doubly labeled water technique). Setting: Normal daily living (unrestricted by the measurement devices). Patients: Thirteen patients with chronic nonspecific LBP and 13 age- and gender-matched healthy controls. Main Outcome Measures: Physical activity in daily life, expressed as whole-body acceleration measured with a triaxial accelerometer (Tracmor), and as the ratio between average daily metabolic rate (ADMR), measured by the doubly labeled water technique, and resting metabolic rate (RMR), measured by the ventilated hood. Both techniques were used simultaneously for 14 days. Results: Mean physical activity level in patients and controls did not differ significantly. The correlation between the Tracmor and ADMR and RMR was.72 (p <.01). Conclusions: Decreased physical activity levels in this sample of chronic LBP patients was not confirmed. The Tracmor is a valid instrument for measuring daily activity in LBP patients.

Increase of physical activity level after successful renal transplantation: a 5 year follow-up study.

Physical activity (PA) level of end-stage renal disease (ESRD) patients after renal transplantation (TP) is a largely unexplored field, although it is an important component of quality of life. Using the Baecke self-administered and the Five-City Project 7-day PA recall questionnaires, PA level was estimated in 32 consecutive ESRD patients (12 males, 20 females; mean age 45.9+/-13.1 years; mean dialysis duration 23.5+/-21.8 months) admitted for renal TP and to whom no exercise programme of any kind was proposed. PA were recorded 1, 3, 6, 12 and 60 months after TP. Immediate pre-TP PA level of renal transplant candidates was between 18 and 35% less than that of age-matched healthy subjects (P < 0.05), depending on gender and questionnaire. After an immediate decrease in PA level 1 month post-TP, mean PA level increased and reached a plateau 1 year after TP. This gain in PA capacity reached 30%, as compared with pre-TP values (P = 0.06 to P < 0.01). During the fifth year after TP, the mean level of PA was unchanged. A more qualitative analysis, allowed by the sub-score comparisons, showed that although the occupational status of the patients remained the same, they participated significantly more in moderate and even high intensity PA (leisure, sports, household chores) after TP. Most renal graft recipients are spontaneously more active after TP, an observation consistent with a better quality of life. Therefore, they should be advised precisely about how to resume more strenuous activities such as sports in order to avoid cardiac or musculoskeletal disorders in relation to their weakened pre-TP condition.

Parental eating attitudes and the development of obesity in children. The Framingham Children's Study.

To investigate the extent to which parents' degree of dietary self-control, as measured by self-reported dietary restraint, disinhibition, and perceived hunger, affects the development of excess body fat in the child. Prospective observational study. Ninety-two 3-5y old children and their parents, enrolled in 1987 in the Framingham Children's Study. Self-reported levels of parental dietary restraint, disinhibition and perceived hunger were estimated using Stunkard and Messick's Three-Factor-Eating Questionnaire. Anthropometric measurements (height, weight and skinfold measurements at five sites) were obtained yearly for children and parents. The child's activity level was measured on multiple days each year using Caltrac accelerometers. Energy intake and percentage of calories from total fat were estimated from multiple sets of food diaries, collected each year. All analyses were adjusted for the following potential confounders: child's sex and baseline values for age, height, mean physical activity level, total calories and percentage of calories from fat as well as the educational levels of the parents at baseline. Over 6y, children's body fat increased linearly with increasing levels of self-reported parental disinhibition (eg 6y increase in the child's sum of five skinfolds was 34.4, 45.8 and 59.2 mm across increasing tertiles of parental disinhibition, P=0.012). Overall, children whose parents had higher dietary restraint scores had greater increases in body fatness than children whose parents had the lowest levels of restraint. When both parents had above average scores on dietary disinhibition or restraint, the children had greater increases in body fat (on all anthropometry measures) than when only one parent or when neither parent had high scores on those factors. Parental scores on the perceived hunger scale had no clear effect on body fat change of children. Since disinhibition and dietary restraint frequently co-exist, we then examined the joint effect of these two factors. The children with the greatest increases in body fat were those whose parents scored high on both factors. In the final analysis, we found that dietary restraint adversely affected the child's body fat only when associated with high parental disinhibition. This study suggests that parents who display high levels of disinhibited eating, especially when coupled with high dietary restraint, may foster the development of excess body fat in their children. This association may be mediated by direct parental role modeling of unhealthy eating behaviors, or through other indirect, and probably subconscious, behavioral consequences such as the suppression of the child's innate regulation of dietary intake.

Food Intake, Physical Activity, and Body Fat in 4-8 Year Old Girls

Physical inactivity is a recognized factor related to obesity, however, the importance of diet composition is less clear. Few studies have looked at diet composition, physical activity, and body composition in very young children. The purpose of this study was to examine the relationships between food intake, physical activity, body mass index (BMI), and body fat in a group of healthy 4-8 year old girls (N=50; 6.0 ±1.5 years). Dietary intakes were assessed using three-day diet records. Nutrient analysis was conducted using Food Processor computer program (ESHA, version 6.21). Physical activity was assessed using a daily activity record. Percent body fat (%BF) and fat mass were determined by dual energy X-ray absorptiometry (QDR 1000/W; Hologic, Inc.). Pearson correlations were conducted using SPSS. Mean caloric intake was 1745.8 ± 406.2 kcals, with 33 ± 0.05% of the calories from fat, 12 ± 0.02% from protein, and 55 ± 0.06% from carbohydrate. Average BMI was 16.5 ±1.5kg/m: (range: 13.7-20.0) and %BF was 21.2 ± 5.0% (range: 14.8-34.2). Mean physical activity level was 109 ± 32minutes per day (range: 40-175). Body mass index was significantly related to total fat intake (r=.333, p<0.05), however, no significant correlations were observed between %BF and % of kcals from fat, total fat intake, total kcal intake, or physical activity level. Adjusting for physical activity level did not change the findings. These results suggest that the amount of fat in the diet nor the level of physical activity was associated with body fatness in this sample of healthy young girls.

A community-based study of explanatory factors for the excess risk for early renal function decline in blacks vs whites with diabetes: the Atherosclerosis Risk in Communities study.

The explanation for the excess risk for diabetic renal disease in blacks is uncertain. To compare the incidence of early renal function decline in black and white adults with diabetes and to examine possible explanatory factors for racial differences. Prospective cohort study. Four US communities participating in the Atherosclerosis Risk in Communities study. Community-based sample of 1434 diabetic adults aged 45 to 64 years. Detailed baseline assessment using structured interview, results of physical examination, and laboratory measurements. Development of early renal function decline defined by an increase in serum creatinine of at least 35.4 micromol/L (0.4 mg/dL) during 3 years of follow-up. During 3 years of follow-up, early renal function decline developed in 45 blacks (28.4 per 1000 person-years [PY]) and 25 whites (9.6 per 1000 PY). After adjustment for age, sex, and baseline serum creatinine level, early renal function decline was more than 3 times as likely to develop in blacks than whites (odds ratio, 3.15; 95% confidence interval, 1.86-5.33). Additional adjustment for education, household income, health insurance, fasting glucose level, mean systolic blood pressure, smoking history, and physical activity level reduced the relative odds in blacks to 1.38 (95% confidence interval, 0.71-2.69), corresponding to a 82% reduction in excess risk. These data suggest that early renal function decline is 3 times more likely to develop in blacks than whites and that potentially modifiable factors, including lower socioeconomic status, suboptimal health behaviors, and suboptimal control of glucose level and blood pressure, account for more than 80% of this disparity.

A Sixty Day Energy Balance Study in Female Japanese College Student: Results of a Validated Study using an Accelerometer

Maintaining the balance between energy intake (EI) and energy expenditure (EE) is essential for long term wellness of healthy adults. Until recently, measurements of EE have been difficult and inaccurate. A new accelerometer (motion sensor) which can distinguish among various postures including sitting, standing, walking and running, and can estimate daily EE has been developed. The purpose of this study was to compare estimates of total EE by this device with those obtained by EI from self reported diet records and physical activity diary (factorial method). We have developed a simple factorial method to reduce burdensome work of recording activities. Twenty six female students (out of 46) successfully completed 60 day recording of dietary intake and physical activity while wearing the accelerometer. The mean total EE obtained by the accelerometer (1696 ± 128 kcal) was approximately 94% of total EE obtained by the factorial method (1797 ± 146 kcal). Mean EI, weight gain, fat gain and physical activity level (multiples of BMR) were 1467±261 kcal, −0.2±1.1 kg, −0.1 ± 1.2 kg and 1.50 ± 0.06 , respectively. The mean energy balance was −330±246 kcal/day, but there was a change of body fat of −22 ± 175 kcal/day. The subjects underestimated dietary intake by about 300 kcal/day. The most serious student continued this study for 106 days and her average energy balance (+124 kcal/day) showed good agreement with her fat gain (+66 kcal/day). These results of this study demonstrated the applicability and reliability of the accelerometer in long term energy balance study.

Total energy expenditure and physical activity as assessed by the doubly labeled water method in Swedish adolescents in whom energy intake was underestimated by 7-d diet records

Swedish children and adolescents may be adopting a sedentary lifestyle with low energy expenditures and intakes, but no quantitative data are available. The purpose of the present study in 50 adolescents aged 15 y was to investigate whether assessment of total energy expenditure (TEE) and physical activity level (PAL) by the doubly labeled water method and indirect calorimetry and estimation of energy intake by a 7-d diet record would indicate physical inactivity. The boys' (n = 25) mean weight was 112% and the girls' (n = 25) was 109% of Swedish reference values from 1976; the mean height of both boys and girls was 102% of those reference values. Mean TEE in the boys and girls, 13.82 +/- 1.90 and 10.70 +/- 1.59 MJ/d, and mean PAL (TEE/basal metabolic rate), 1.89 +/- 0.16 and 1.79 +/- 0.22, respectively, were nonsignificantly higher than corresponding figures from other published studies. Mean energy intake as a percentage of TEE was 81.9 +/- 17.9% in the boys and 78.3 +/- 16.4% in the girls. Significant negative correlations were found both between energy intake as a percentage of TEE and percentage body fat and between energy intake as a percentage of TEE and body mass index. These results add to the evidence that 7-d diet records underestimate energy intake in adolescents, particularly those with a tendency for overweight and increased body fat. The results support indications of a trend of increasing body weight and height in Swedish adolescents, but conflict with the presumptions of low physical activity, low energy expenditure, and low energy intake. These results support the view that current recommendations for energy intake during adolescence are too low.