Low cardiorespiratory fitness and physical inactivity as predictors of mortality in men with type 2 diabetes

BACKGROUND: Although physical activity is recommended as a basic treatment for patients with diabetes, its long-term association with mortality in these patients is unknown. OBJECTIVE: To evaluate the association of low cardiorespiratory fitness and physical inactivity with mortality in men with type 2 diabetes. DESIGN: Prospective cohort study. SETTING: Preventive medicine clinic. PATIENTS: 1263 men (50+/-10 years of age) with type 2 diabetes who received a thorough medical examination between 1970 and 1993 and were followed for mortality up to 31 December 1994. MEASUREMENTS: Cardiorespiratory fitness measured by a maximal exercise test, self-reported physical inactivity at baseline, and subsequent death determined by using the National Death Index. RESULTS: During an average follow-up of 12 years, 180 patients died. After adjustment for age, baseline cardiovascular disease, fasting plasma glucose level, high cholesterol level, overweight, current smoking, high blood pressure, and parental history of cardiovascular disease, men in the low-fitness group had an adjusted risk for all-cause mortality of 2.1 (95% CI, 1.5 to 2.9) compared with fit men. Men who reported being physically inactive had an adjusted risk for mortality that was 1.7-fold (CI, 1.2-fold to 2.3-fold) higher than that in men who reported being physically active. CONCLUSIONS: Low cardiorespiratory fitness and physical inactivity are independent predictors of all-cause mortality in men with type 2 diabetes. Physicians should encourage patients with type 2 diabetes to participate in regular physical activity and improve cardiorespiratory fitness.     

Changes in physical activity explain paradoxical relationship between baseline physical activity and adiposity changes in adolescent girls: the FLVS II study

OBJECTIVE: To investigate in adolescents relationships between habitual physical activity (PA) and changes in several indicators of adiposity. DESIGN: Longitudinal population-based study. The Fleurbaix-Laventie Ville Sante II (FLVS II) study in Northern France. SUBJECTS: A total of 222 boys and 214 girls aged 8-18 y, not obese at inclusion. MEASUREMENTS: PA (Modifiable Activity Questionnaire) and adiposity (body mass index (kg/m2), percent body fat by bioimpedance analysis, sum of four skinfolds, waist circumference) were assessed in 1999 and 2001. Adiposity indicators adjusted for age and pubertal stage were compared between groups of baseline PA and between groups of PA changes, separately by sex. RESULTS: At baseline, PA was not associated with adiposity indicators in both sexes. In girls only, being in the group with the highest age-relative level of moderate PA at baseline predicted the highest adiposity gain from baseline to follow-up, for all indicators. After adjustment for baseline values, all adiposity indicators were higher at follow-up in girls who had decreased their relative level of moderate PA during follow-up. In boys, changes in adiposity during follow-up were not significantly different across groups of PA changes. However, the sum of skinfolds at follow-up, adjusted for baseline value, tended to be higher in those who decreased their vigorous PA level and lower in those who increased it. CONCLUSION: In adolescent girls, a decrease in PA rather than inactivity per se may result in increased adiposity over time.     

Impact of body mass index, physical activity, and other clinical factors on cardiorespiratory fitness (from the Cooper Center longitudinal study)

Cardiorespiratory fitness (CRF) is widely accepted as an important reversible cardiovascular risk factor. In the present study, we examined the nonmodifiable and modifiable determinants of CRF within a large healthy Caucasian population of men and women. The study included 20,239 patients presenting to Cooper Clinic (Dallas, Texas) for a comprehensive medical examination from 2000 through 2010. CRF was determined by maximal treadmill exercise testing. Physical activity categories were 0 metabolic equivalent tasks (METs)/min/week (no self-reported moderate or vigorous intensity physical activity), 1 to 449 METs/min/week (not meeting physical activity guideline), 450 to 749 METs/min/week (meeting guideline), and ≥750 METs/min/week (exceeding guideline). Linear regression modeling was used to determine the most robust clinical factors associated with achieved treadmill time. Age, gender, body mass index (BMI), and physical activity were the most important factors associated with CRF, explaining 56% of the variance (R(2) = 0.56). The addition of all other factors combined (current smoking, systolic blood pressure, blood glucose, high-density and low-density lipoprotein cholesterol, health status) were associated with CRF (p <0.05) but additively only improved R(2) by 2%. There was a significant interaction between BMI and physical activity on CRF, such that normal-weight (BMI <25 kg/m(2)) subjects achieved higher CRF for a given level of physical activity compared to obese subjects (BMI ≥30 kg/m(2)). Percent body fat, not lean body mass, was the key factor driving this interaction. In conclusion, BMI was the most important clinical risk factor associated with CRF other than nonmodifiable risk factors age and gender. For a similar amount of physical activity, normal-weight subjects achieved a higher CRF level compared to obese subjects. These data suggest that obesity may offset the benefits of physical activity on achieved CRF, even in a healthy population of men and women.     

Poor physical fitness,and impaired early insulin response but late hyperinsulinaemia,as predictors of NIDDM in middle-aged Swedish men

Summary In a prospective population-based study of middle-aged Caucasian men, performed in Malmö, Sweden, specifically designed to evaluate physical fitness, early and late insulin response as predictors of non-insulin-dependent diabetes mellitus (NIDDM), 4,637 non-diabetic men underwent oral glucose tolerance tests at the ages of 48 and 54 years. At the baseline examination, physical fitness was measured in terms of lung vital capacity and oxygen uptake during ergometry; early insulin response in terms of the 40-min insulin increment during an oral glucose tolerance test (a correlate of acute insulin response to an intravenous glucose tolerance test), and late insulin response were measured in terms of the 2-h insulin value during the oral glucose tolerance test (a correlate of glucose disposal during euglycaemic clamp testing). Of the subjects studied 116 developed NIDDM (0.4% annually), and when compared with non-diabetic men at baseline, they were found to have an 11% higher mean body mass index (p<0.001), a higher frequency of family history of diabetes (31 vs 18%, p<0.001), 16% lower mean physical activity index (p<0.05), 16% lower mean estimated maximal oxygen uptake (p<0.001), 10% lower mean vital capacity (p<0.001), 26% lower 40-min to total insulin response ratio (p<0.001), and a 2.7 times higher mean 2-h insulin value during an oral glucose tolerance test (p<0.001). Regression analysis (using Cox's proportional hazards model) showed both low vital capacity, and impaired early insulin response but late hyperinsulinaemia to be independent predictors of NIDDM, in addition to body mass index and fasting blood glucose level (p=0.05–0.0001). Among subjects with impaired glucose tolerance at baseline (44 of 278 developed NIDDM), fasting glucose level alone predicted diabetes in this model. The findings suggest that in this age group in a Caucasian population, not only does insulin resistance precede glucose intolerance and NIDDM, but also loss of early insulin response indicating impaired beta-cell function to be an early feature of the process culminating in diabetes. As both physical fitness [which correlates inversely with late insulin response (r=–0.42, p<0.0001)], and the level of physical activity were shown to correlate with diabetes development in this large series, measures to correct these adverse features should be included in future strategies for preventing NIDDM.Abbreviations OGTT Oral glucose tolerance test - NGT normal glucose tolerance - IGT impaired glucose tolerance - NIDDM non-insulin-dependent diabetes mellitus - BMI body mass index - IVGTT intravenous glucose tolerance test     

Indicators of abdominal adiposity in middle-aged participants of the SU.VI.MAX study: relationships with educational level, smoking status and physical inactivity

OBJECTIVES: Abdominal fat accumulation is a risk factor for type 2 diabetes and cardiovascular disease. Identifying the demographic and lifestyle correlates of abdominal adiposity is an important step to target at-risk populations in prevention programs. There are few data of this kind in France. METHODS: Anthropometric indicators of overall (body mass index, BMI) and abdominal (waist hip ratio, WHR; waist circumference, WC) adiposity, educational level, smoking status, and physical activity were assessed in 6,705 middle-aged men and women participating in the SU.VI.MAX study. RESULTS: The likelihood of being obese was increased more than twice in physically inactive subjects of both genders after adjustment for age, smoking status and educational level (OR=2.22, CI95%: 1.74-2.83 in men; OR=2.38, CI95%: 1.84-3.09 in women). Having a high WHR (>=0.95 in men, >=0.80 in women) was more likely in subjects >=50 y, in current smokers, and less likely in men with higher education. The likelihood of having a high WHR was also increased in physically inactive subjects of both genders after adjustment for age, BMI, smoking status and educational level (OR=1.33, CI95%: 1.10-1.60 in men; OR=1.46, CI95%: 1.22-1.74 in women). Having a high WC (>=102 cm in men, >=88 cm in women) was positively associated with age and also with physical inactivity (OR=1.63, CI95%: 1.20-2.22 in women). CONCLUSIONS: These cross-sectional data suggest significant positive associations of physical inactivity with both the WHR and WC, independently of overall adiposity as assessed by the BMI.     

School-based obesity prevention in Chilean primary school children: methodology and evaluation of a controlled study

OBJECTIVE: To assess the impact of a 6 months nutrition education and physical activity intervention on primary school children through changes in adiposity and physical fitness. DESIGN: Longitudinal school-based controlled evaluation study. SUBJECTS: Children from 1st to 8th grade, 2141 in intervention and 945 in control schools. INTERVENTION: Nutrition education for children and parents, 'healthier' kiosks, 90 min of additional physical activity (PA) weekly, behavioral PA program and active recess. MEASUREMENTS: Adiposity indices (BMI, BMI Z-score, triceps skinfold thickness (TSF), waist circumference and physical fitness (20 m shuttle run test and lower back flexibility). RESULTS: Positive effect on adiposity indices (except TSF) was observed in boys (P<0.001 for BMI Z), while both physical fitness parameters increased significantly in both boys (P<0.001 for each test) and girls (P<0.0001 for each test). A differential effect in BMI Z was observed according to baseline nutritional status. CONCLUSIONS: This intervention showed a robust effect on physical fitness in both genders and decreased adiposity only in boys.     

Physical fitness related to disability in older persons

BACKGROUND: In today's aging society, preventing or reducing disability is important. Physical activity may serve this goal. Generally, physical activity aims to enhance physical fitness, which in turn may prevent disability. The relationship between physical fitness and disability has been much less explored than the relationship between physical activity and physical fitness. OBJECTIVE: To investigate the relationship between separate components of physical fitness and disability. METHODS: The subjects were a community-based sample of 176 men and 233 women aged 65 years or older. Physical fitness was assessed with performance-based tests. Disability and potential confounders were assessed during face-to-face interviews. RESULTS: Independently of other fitness components, walking endurance, grip strength, manual dexterity and balance contributed significantly to the prediction of disability for both men and women. Flexibility of the hip and spine, flexibility of the shoulder and reaction time were not independent predictors of disability for men or women. Physical fitness explained a greater percentage of variance in disability for women (31-48%) than for men (14-34%). Although depressive symptoms, cognitive functioning (men), number of chronic conditions (women) and age (women) explained additional variance in disability, these variables did not confound the relationship between physical fitness and disability. CONCLUSION: Walking endurance, grip strength and manual dexterity are important unique predictors of disability. Physical activity programs should be directed at these fitness components.     

Factors Associated With Cardiorespiratory Fitness at Completion of Cardiac Rehabilitation: Identification of Specific Patient Features Requiring Attention

Background

We aimed to determine and compare predictors of postcardiac rehabilitation (CR) cardiorespiratory fitness (CRF), improvements in a large cohort of subjects with varying baseline CRF levels completing CR for ischemic heart disease and to refine prediction models further by baseline CRF.

Body mass index, waist circumference, and waist-hip ratio on the risk of total and type-specific stroke

BACKGROUND: Adiposity is an established risk factor for cardiovascular disease, but the relationship of adiposity with the risk of cerebrovascular disease is still to some extent unclear. METHODS: We prospectively investigated the association of different indicators of adiposity (body mass index [BMI] [calculated as weight in kilograms divided by height in meters squared], waist circumference, and waist-hip ratio) with total and type-specific stroke incidence among 49 996 Finnish participants who were aged 25 to 74 years and free of coronary heart disease and stroke at baseline. RESULTS: During a 19.5-year follow-up, 3228 people developed an incident stroke event (674 hemorrhagic and 2554 ischemic). Compared with normal-weight men (BMI, 18.5-24.9), the multivariate-adjusted (age, study year, smoking, physical activity, educational level, family history of stroke, and alcohol drinking) hazard ratios among lean (BMI, < 18.5), overweight (BMI, 25.0-29.9), and obese (BMI, > or = 30.0) men were 0.74 (95% confidence interval [CI], 0.18-2.96), 1.23 (95% CI, 1.10-1.37), and 1.59 (95% CI, 1.37-1.83) for total stroke, and 0.49 (95% CI, 0.07-3.50), 1.27 (95% CI, 1.12-1.44), and 1.70 (95% CI, 1.45-2.00) for ischemic stroke, respectively. Among women, the corresponding hazard ratios were 1.87 (95% CI, 1.12-3.14), 1.08 (95% CI, 0.95-1.22), and 1.30 (95% CI, 1.14-1.50) for total stroke, and 1.81 (95% CI, 0.97-3.41), 1.11 (95% CI, 0.96-1.28), and 1.41 (95% CI, 1.21-1.64) for ischemic stroke. Abdominal adiposity, defined as the highest quartile of waist circumference or waist-hip ratio, was associated with a greater risk of total and ischemic stroke in men but not in women. CONCLUSIONS: Body mass index was a risk factor for total and ischemic stroke in men and women. Abdominal adiposity was a risk factor for total and ischemic stroke only in men.     

Comparison of the clinical profile and outcome of women and men in cardiac rehabilitation.

Few data are available regarding the outcome of women in cardiac rehabilitation. To determine whether women differ from men in clinical profile and outcome, 225 consecutive patients were prospectively evaluated in an urban, multidisciplinary, exercise-based cardiac rehabilitation program. Among the 51 women (age 56 +/- 10) and 174 men (age 54 +/- 10), most were: white (84%), married (64%), employed (63%), had had myocardial infarction or revascularization, or both (66%), and traveled less than 10 miles to the program (92%). Risk profiles revealed obesity in 48% (mean Metropolitan Relative Weight = 124 +/- 22%), hypertension in 47%, smoking in 23%, diabetes in 16%, and mean cholesterol of 236 +/- 45 mg/dl. Compared with men, more women were nonwhite, unemployed, unmarried, hypertensive or diabetic (p less than 0.0001) and had higher cholesterol (p less than 0.01). Compliance rates were similar for women (51%) and men (63%) (p = not significant). Univariate predictors of program noncompliance differed between women and men. Initial exercise capacity was less for women than for men, but both groups achieved a similar training effect. Women increased their exercise time by 31% and peak METs by 30%, whereas men showed a 21% increase in exercise time and 16% increase in peak METs achieved (p less than 0.001). Thus, in this cardiac rehabilitation program, women have a less favorable risk factor profile and differ from men with regard to baseline demographics and predictors of program completion. Women, however, have similar rates of compliance and achieve the same improvement in functional capacity with training.     

Joint effects of physical activity, body mass index, waist circumference and waist-to-hip ratio with the risk of cardiovascular disease among middle-aged Finnish men and women.

AIMS: To assess joint associations of physical activity and different indicators of obesity (body mass index, waist circumference, and waist-to-hip ratio) with the risk of cardiovascular disease (CVD). METHODS AND RESULTS: The study comprised 18,892 Finnish men and women aged 25-74 years without history of coronary heart disease, stroke, or heart failure at baseline. Physical activity, different indicators of obesity, education, smoking, blood pressure, total and high-density lipoprotein cholesterol and history of diabetes were measured at baseline. An incident CVD event was defined as the first stroke or coronary heart disease event or CVD death based on national hospital discharge and mortality register data. The median follow-up time was 9.8 years. Physical activity had a strong, independent, and inverse association with CVD risk in both genders. All obesity indicators had a significant direct association with CVD risk after adjustment for age, smoking, education and physical activity. Further adjustment for the obesity-related risk factors weakened the associations and they remained statistically significant in men only. Physical activity and the obesity indicators both predicted CVD risk in men, but in women the joint effect was inconsistent. CONCLUSION: Both regular physical activity and normal weight can reduce the risk of CVD. Physical inactivity seems to have an independent effect on CVD risk, whereas obesity increases the risk partly through the modification of other risk factors.     

Importance of physical fitness on predictive effect of body mass index and weight gain on incident atrial fibrillation in healthy middle-age men

The incidence of both atrial fibrillation (AF) and obesity is increasing in the community, and lifestyle intervention is recommended. We aimed to test whether the predictive effect of body mass index (BMI) and weight change from age 25 years to midlife on incident AF were influenced by physical fitness. In 1972 to 1975, 2,014 healthy middle-age men conducted a bicycle exercise electrocardiographic test as a part of a cardiovascular survey program, defining physical fitness as work performed divided by body weight. During 35 years of follow-up, 270 men developed AF, documented by scrutiny of the health files in all Norwegian hospitals. Risk estimation was analyzed using Cox proportional hazard models and tested for age-adjusted physical fitness above and below the median. The mean BMI of 24.6 kg/m(2) defined a lean baseline cohort. The men with a baseline BMI of ≥28 kg/m(2) (11%) compared to a BMI <28 kg/m(2) had a 1.68-fold risk of AF (95% confidence interval 1.14 to 2.40) and men reporting weight gain of ≥10 kg (24%) compared to weight loss (11%) of 1.66-fold (95% confidence interval 1.00 to 2.89), respectively. The dichotomy into men with age-adjusted physical fitness above and below the median, demonstrated statistically significant risk associations only for men with low fitness. The overall risk of AF was reduced by 23% in the fit men. In conclusion, within our lean baseline cohort of healthy middle-age men, a BMI of ≥28 kg/m(2) and weight gain of ≥10 kg from age 25 to midlife were long-term predictors of incident AF in men with physical fitness below the population median. The fit men had an overall slightly reduced risk of AF.     

Joint effects of adiposity and physical activity on incident mobility limitation in older adults

OBJECTIVES: To examine joint associations of physical activity and adiposity measures (body mass index (BMI), waist circumference, percentage body fat) with incident mobility limitation. DESIGN: Prospective observational cohort study. SETTING: Memphis, Tennessee and Pittsburgh, Pennsylvania. PARTICIPANTS: Two thousand nine hundred and eighty‐two black and white men and women aged 70 to 79 participating in the Health, Aging and Body Composition (Health ABC) study. MEASUREMENTS: Mobility limitation was defined as reported difficulty walking one‐quarter of a mile or climbing 10 steps during two consecutive semiannual assessments over 6.5 years. Three measures of adiposity were included in this study: BMI, total percentage body fat, and waist circumference. Physical activity was assessed using a modified leisure‐time physical activity questionnaire. RESULTS: Forty‐six percent of the cohort developed mobility limitation. White and black men with a high BMI (≥30 kg/m²), high total percentage body fat (>31.3%), or high waist circumference (≥102 cm) had an approximately 60%, 40%, and 40%, respectively, higher risk of incident mobility limitation than those with low adiposity. In women, high adiposity was also associated with a significantly higher mobility limitation risk than in those with low adiposity. Low physical activity (lowest quartile) was associated with a 70% higher risk of mobility limitation in all groups. Persons with high adiposity and low physical activity were at particularly high risk of mobility limitation. People with high adiposity who were physically active had an equally high risk of mobility limitation as inactive people with low adiposity. CONCLUSION: High adiposity and low self‐reported physical activity predicted the onset of mobility limitation in well‐functioning older persons. Preventing weight gain in old age and promoting physical activity in obese and non‐obese older persons may therefore be effective strategies to prevent mobility loss and future disability.     

Comparison of cardiorespiratory fitness versus leisure time physical activity as predictors of coronary events in men aged < or = 65 years and > 65 years

Both high peak oxygen consumption (VO(2)) and high levels of leisure time physical activity (LTPA) are associated with a reduced risk of cardiovascular morbidity and mortality. We examined the contributions of LTPA and peak VO(2) to the risk of coronary events (CEs) in healthy younger (< or = 65 years, n = 522) and older (>65 years, n = 167) men from the Baltimore Longitudinal Study of Aging. LTPA derived from self reports of time spent in 97 activities were converted into METs-minutes/24 hours and grouped into high (> or = 6 METs), moderate- (4 to 5.9 METs), and low-intensity LTPA (<4 METs). Cardiorespiratory fitness was determined by measuring peak VO(2) during a maximal treadmill exercise test. Over a mean follow-up of 13.4 +/- 6.3 years, CEs occurred in 63 men. After accounting for coronary risk factors, proportional-hazards analyses showed a relative CE risk of 0.53 (p <0.0001) for a SD increase in peak VO(2) in younger men and 0.61 (p = 0.024) in older men, whereas total LTPA was unrelated to coronary risk in either age group. When the 3 LTPA intensity levels were substituted for total LTPA in the model, peak VO(2) remained the only predictor of events in younger men, whereas high-intensity LTPA (RR = 0.39 for tertile 3 vs tertiles 1 and 2, p = 0.016) and peak VO(2) (RR = 0.61/SD increase, p = 0.024) were of similar importance in older men. Thus, in healthy younger men, higher cardiorespiratory fitness but not LTPA predicts a reduced risk of coronary heart disease, independent of conventional risk factors. For older men, high-intensity LTPA and fitness appear to be of similar importance in reducing coronary risk.     

C-Reactive protein is inversely related to physical fitness in middle-aged subjects

INTRODUCTION: Physical fitness has a protective effect with regard to the risk of developing coronary disease or diabetes. C-reactive protein (CRP) levels are directly related to increased risk of coronary disease and diabetes. However, data on the association between physical fitness and CRP are sparse. METHODS: Physical fitness was assessed in a population-based cross-sectional study (n = 892; age 50 +/- 9 years) using the Bruce treadmill protocol. CRP was measured using a high-sensitivity assay. RESULTS: Geometric mean CRP levels were calculated across quartiles of physical fitness after adjustment for age, gender, body mass index, smoking habit, presence of diabetes and hypertension, HDL cholesterol and triglyceride levels, and use of hormone replacement therapy, statins, and aspirin. CRP levels decreased with increasing quartiles of fitness (P for trend <0.0001). When used as a continuous variable in a stepwise linear regression model, the geometric mean of CRP decreased by 0.061 mg/L (95% confidence interval (CI) 0.034-0.089 mg/L) for each 1 unit increase in metabolic equivalents (METs). Multivariate logistic regression models showed that compared to subjects in the lowest fitness quintile, subjects in the highest fitness quintile had significantly lower adjusted odds of having a high-risk (>3 mg/L) CRP level (OR 0.53; 95% CI 0.39-0.71, P = 0.007). CONCLUSION: CRP concentration decreases continuously with increasing levels of physical fitness. The health-related salutary effects of physical fitness may be mediated, in part, through an antiinflammatory mechanism.     

Determining the amount of physical activity needed for long-term weight control

OBJECTIVE: To evaluate prospectively the influence of habitual physical activity on body weight of men and women and to develop a model that defines the role of physical activity on longitudinal weight change. DESIGN AND SETTING: Occupational cohort study conducted for a mean of 5.5 y. SUBJECTS: A total of 496 (341 male and 155 female) NASA/Johnson Space Center employees who completed the 3 month education component of the employee health-related fitness program and remained involved for a minimum of 2 y. MEASUREMENTS: Body weights were measured at baseline (T1) and follow-up (T2), and habitual physical activity was obtained from the mean of multiple ratings of the 11-point (0-10) NASA Activity Scale (NAS) recorded quarterly between T1 and T2. Other measures included age, gender, VO(2 max) obtained from maximal treadmill testing, body mass index (BMI), and body fat percentage. RESULTS: Multiple regression demonstrated that mean NAS, T1 weight, aging and gender all influence long-term T2 weight. T1 age was significant for the men only. Independently, each increase in mean NAS significantly (P<0.01) reduced T2 weight in men (b=-0.91 kg; 95% CI:-1.4 to-0.42 kg) and women (b=-2.14 kg; 95% CI:-2.93 to-1.35 kg). Mean NAS had a greater effect on T2 weight as T1 weight increased, and the relationship was dose-dependent. CONCLUSIONS: Habitual physical activity is a significant source of long-term weight change. The use of self-reported activity level is helpful in predicting long-term weight changes and may be used by health care professionals when counseling patients about the value of physical activity for weight control.     

Physical activity and dehydroepiandrosterone sulphate, insulin-like growth factor I and testosterone in healthy active elderly people.

OBJECTIVE: to examine the association of physical activity and cardio-respiratory fitness with dehydroepiandrosterone sulphate (DHEAS), insulin-like growth factor I (IGF-I) and testosterone in healthy elderly people. DESIGN: cross-sectional study. SETTING: university research department and department of geriatric medicine. PARTICIPANTS: 60 independent, community-dwelling elderly subjects (26 men and 34 women) aged 66-84 who volunteered to participate. MEASUREMENTS: physical activity was evaluated by the Questionnaire d'Activité Physique Saint-Etienne and expressed by three indices: mean habitual daily energy expenditure (MHDEE), daily energy expenditure (DEE) [comprising activities with intensities corresponding to at least three metabolic equivalents (MET; 3.5 ml.kg1 x min1 of oxygen consumption)] and sport activity. Cardio-respiratory fitness was expressed by maximal oxygen consumption (VO2max). RESULTS: In women, DHEAS correlated with VO2max (partial correlation: r=0.33; P=0.05), MHDEE (r=0.50; P=0.002), DEE > 3 METs (r=0.49; P=0.003) and sport activity (r=0.35; P=0.04) whereas IGF-I correlated with MHDEE (r=0.48; P=0.004). DHEAS was correlated with IGF-I (r=0.43; P < 0.02) and with testosterone (r=0.41; P < 0.02). No such correlation was found in men. CONCLUSION: lower habitual physical activity is related to lower levels of circulating DHEAS and IGF-I independently of age and anthropometric measures. Lower maximal aerobic capacity is associated with lower DHEAS concentrations, in healthy elderly women.     

The association between cardiorespiratory fitness and impaired fasting glucose and type 2 diabetes mellitus in men

BACKGROUND: Several studies show an inverse association between self-reported physical activity and type 2 diabetes. It is not known whether physical activity or cardiorespiratory fitness is associated with the onset of objectively determined impaired fasting glucose and type 2 diabetes. OBJECTIVE: To determine whether cardiorespiratory fitness, an objective marker of physical activity, is associated with risk for impaired fasting glucose and type 2 diabetes. DESIGN: Population-based prospective study. SETTING: Preventive medicine clinic. PATIENTS: 8633 nondiabetic men (of whom 7511 did not have impaired fasting glucose) who were examined at least twice. MEASUREMENTS: Cardiorespiratory fitness (determined by a maximal exercise test on a treadmill), fasting plasma glucose level, and other clinical and personal characteristics and incidence of impaired fasting glucose and type 2 diabetes. RESULTS: During an average follow-up of 6 years, 149 patients developed type 2 diabetes and 593 patients developed impaired fasting glucose. After age, cigarette smoking, alcohol consumption, and parental diabetes were considered, men in the low-fitness group (the least fit 20% of the cohort) at baseline had a 1.9-fold risk (95% CI, 1.5- to 2.4-fold) for impaired fasting glucose and a 3.7-fold risk (CI, 2.4- to 5.8-fold) for diabetes compared with those in the high-fitness group (the most fit 40% of the cohort). The risk for impaired fasting glucose was elevated in older men and those with a higher body mass index. Age, body mass index, blood pressure, triglyceride level, and a history of parental diabetes were also directly related to risk for type 2 diabetes. CONCLUSIONS: Low cardiorespiratory fitness was associated with increased risk for impaired fasting glucose and type 2 diabetes. A sedentary lifestyle may contribute to the progression from normal fasting glucose to impaired fasting glucose and diabetes. Risk for type 2 diabetes was elevated in older persons and those with higher body mass index, blood pressure, and triglyceride levels and a parental history of diabetes.     

Leisure time physical activity and the risk of type 2 diabetes in men and women from the general population

Aims/hypothesis The aim of this study was to examine sex-specific associations between leisure time physical activity and incident type 2 diabetes in a representative population sample in Germany.Methods The study was based on 4,069 men and 4,034 women (aged 25 to 74 years) who participated in one of the three MONICA Augsburg surveys between 1984 and 1995. Subjects were free of diabetes at baseline. Incident cases of type 2 diabetes were assessed in 1998 using a follow-up questionnaire. Sex-specific hazard ratios (HRs) were estimated from Cox proportional hazard models.Results A total of 145 cases of incident type 2 diabetes among men and 82 among women were registered during the mean follow-up period of 7.4 years. In both sexes, a high leisure time physical activity level was associated with a reduced risk of incident type 2 diabetes. After adjustment for confounding factors, the HR in highly active men (more than 2 h physical activity per week in summer and winter) was 0.83 (95% CI: 0.50–1.36). In contrast, highly active women had the lowest risk of type 2 diabetes even after multivariable adjustment (HR 0.24; 95% CI: 0.06–0.98). In subgroup analyses, after multivariable adjustment, the protective effect of moderate to high physical activity was significant in women with a BMI below 30 kg/m² (HR 0.24; 95% CI: 0.09–0.65) but not in women with a BMI of 30 kg/m² or higher (HR 0.97; 95% CI: 0.44–2.11).Conclusions/interpretation Leisure time physical activity is effective in preventing type 2 diabetes, especially in nonobese women, in the general population.     

Survival benefit of abdominal adiposity: a 6-year follow-up study with Dual X-ray absorptiometry in 3,978 older adults

In contrast to that in the middle-aged, higher body mass index (BMI) in older people is associated with higher survival rates. Yet, BMI makes no distinction between fat elsewhere and abdominal fat, the latter being metabolically more harmful. We hypothesized that overall adiposity might be protective in old age, but that central fat might offset that benefit and remained harmful as in the middle-aged. Three thousand nine hundred seventy-eight Chinese elderly ≥65 years had demographics, medical conditions, physical activity, and body composition by DXA recorded at baseline. Overall adiposity was measured as whole body fat%, and abdominal adiposity as waist circumference, waist–hip ratio, and relative abdominal fat (RAF) (relative abdominal fat = abdominal fat according to anatomical landmarks/whole body fat). Deaths within 1 year from baseline were excluded from analysis. All-cause and cardiovascular mortality were analyzed using Cox regression, adjusted for covariates. The lowest quintile of adiposity measurements was used for comparison. After a mean follow-up of 72.3 months, 13.7% men and 4.5% women had died. In men, the highest two quintiles of whole body fat % and the upper four quintiles of RAF were associated with significantly lower all-cause mortality, and adjusted hazard ratio (95% CI) in ascending quintiles of RAF compared with the lowest quintile was 0.62 (0.43–0.89), 0.58 (0.4–0.85), 0.52 (0.36–0.77), and 0.67 (0.47–0.96). No relationship was found between abdominal adiposity and cardiovascular mortality in both genders. Higher whole body fat % as well as higher proportion of abdominal fat was associated with lower all-cause mortality in men. No such relation was found in women.