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Objective: To investigate pedometer-measured physical activity (PA) in 2000 and change in PA over 5 years with subsequent risk of dysglycemia by 2005.Research Design and Methods: This prospective cohort study in Tasmania, Australia, analyzed 458 adults with normal glucose tolerance and a mean (SD) age of 49.7 (12.1) years in 2000. Variables assessed in 2000 and 2005 included PA, by pedometer and questionnaire, nutrient intake, and other lifestyle factors. Incident dysglycemia was defined as the development of impaired fasting glucose or impaired glucose tolerance revealed by oral glucose tolerance testing in 2005, without type 2 diabetes.Results: Incident dysglycemia developed in 26 participants during the 5-year period. Higher daily steps in 2000 were independently associated with a lower 5-year risk of incident dysglycemia (adjusted odds ratio [AOR] 0.87 [95% CI 0.77-0.97] per 1,000-step increment). Higher daily steps in 2005, after controlling for baseline steps in 2000 (thus reflecting change in steps over 5 years), were not associated with incident dysglycemia (AOR 1.02 [0.92-1.14]). Higher daily steps in 2000 were also associated with lower fasting blood glucose, but not 2-h plasma glucose by 2005. Further adjustment for BMI or waist circumference did not remove these associations.Conclusions: Among community-dwelling adults, a higher rate of daily steps is associated with a reduced risk of incident dysglycemia. This effect appears to be not fully mediated through reduced adiposity. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study was to compare the predictive ability of the National Cholesterol Education Panel (NCEP), revised NCEP (NCEP-R), and International Diabetes Federation (IDF) metabolic syndrome criteria for mortality risk, and to examine the effects of waist circumference on mortality within the context of these criteria.Research Design and Methods: The sample included 20,789 white, non-Hispanic men 20-83 years of age from the Aerobics Center Longitudinal Study. The main outcome measures were all-cause and cardiovascular disease (CVD) mortality over 11.4 years of follow-up.Results: The proportions of men with the metabolic syndrome were 19.7, 27, and 30% at baseline, respectively, according to NCEP, NCEP-R, and IDF criteria. A total of 632 deaths (213 CVD) occurred. The relative risks (RRs) and 95% CIs of all-cause mortality were 1.36 (1.14-1.62), 1.31 (1.11-1.54), and 1.26 (1.07-1.49) for the NCEP, NCEP-R, and IDF definitions, respectively. The corresponding RRs for CVD mortality were 1.79 (1.35-2.37), 1.67 (1.27-2.19), and 1.67 (1.27-2.20). Additionally, there was a significant trend for a higher risk of CVD mortality across waist circumference categories (<94, 94-102, and >102 cm) among men with at least two additional metabolic syndrome risk factors (P = 0.01).Conclusions: The prediction of mortality with IDF and NCEP metabolic syndrome criteria was comparable in men. Waist circumference is a valuable component of metabolic syndrome; however, the IDF requirement of an elevated waist circumference warrants caution given that a large proportion of men with normal waist circumference have multiple risk factors and an increased risk of mortality. [ABSTRACT FROM AUTHOR]

Objective: To determine in normal weight, overweight, and obese men the risk of all-cause and cardiovascular disease (CVD) mortality associated with the metabolic syndrome (MetS) and the influence of cardiorespiratory fitness (CRF).Research Design and Methods: This observational cohort study included 19,173 men who underwent a clinical examination, including a maximal exercise test. MetS was defined according to National Cholesterol Education Program guidelines.Results: At baseline 19.5% of the men had MetS. The ORs of the metabolic syndrome at baseline were 4.7 (95% CI 4.2-5.3) in overweight and 30.6 (26.7-35.0) in obese men compared with normal weight men. A total of 477 deaths (160 CVD) occurred in 10.2 years of follow-up. The risks of all-cause mortality were 1.11 (0.75-1.17) in normal weight, 1.09 (0.82-1.47) in overweight, and 1.55 (1.14-2.11) in obese men with MetS compared with normal weight healthy men. The corresponding risks for CVD mortality were 2.06 (0.92-4.63) in normal weight, 1.80 (1.10-2.97) in overweight, and 2.83 (1.70-4.72) in obese men with the MetS compared with normal weight healthy men. After the inclusion of CRF in the model, the risks associated with obesity and MetS were no longer significant.Conclusions: Obesity and MetS are associated with an increased risk of all-cause and CVD mortality; however; these risks were largely explained by CRF. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the impact of exercise training (ET) on metabolic parameters among participants with type 2 diabetes mellitus (T2DM) who do not improve their cardiorespiratory fitness (CRF) with training., Research Design and Methods: We studied participants with T2DM participating in the Health Benefits of Aerobic and Resistance Training in Individuals With Type 2 Diabetes (HART-D) trial who were randomized to a control group or one of three supervised ET groups for 9 months. Fitness response to ET was defined as a change in measured peak absolute oxygen uptake (ΔVO(2peak), in liters per minute) from baseline to follow-up. ET participants were classified based on ΔVO(2peak) into fitness responders (ΔVO(2peak) ≥5%) and nonresponders (ΔVO(2peak) <5%), and changes in metabolic profiles were compared across control, fitness responder, and fitness nonresponder groups., Results: A total of 202 participants (mean age 57.1 ± 7.9 years, 63% women) were included. Among the exercise groups (n = 161), there was substantial heterogeneity in ΔVO(2peak); 57% had some improvement in CRF (ΔVO(2peak) >0), with only 36.6% having a ≥5% increase in VO(2peak). Both fitness responders and nonresponders (respectively) had significant improvements in hemoglobin A1c and measures of adiposity (ΔHbA(1c): -0.26% [95% CI -0.5 to -0.01] and -0.26% [-0.45 to -0.08]; Δwaist circumference: -2.6 cm [-3.7 to -1.5] and -1.8 cm [-2.6 to -1.0]; Δbody fat: -1.07% [-1.5 to -0.62] and -0.75% [-1.09 to -0.41]). No significant differences were observed in the degree of change of these metabolic parameters between fitness responders and nonresponders. Control group participants had no significant changes in any of these metabolic parameters., Conclusions: ET is associated with significant improvements in metabolic parameters irrespective of improvement in cardiorespiratory fitness., (© 2015 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.)

Objective: The purpose of this study was to examine independent and joint associations of cardiorespiratory fitness (CRF) and different adiposity measures with mortality risk in individuals with prediabetes (or impaired fasting glucose)., Research Design and Methods: We examined associations of CRF and fatness with cardiovascular disease (CVD) and all-cause mortality in a cohort of 17,044 participants (89% men) with prediabetes (defined as 100 mg/dL ≤ fasting plasma glucose < 126 mg/dL), who did not have a history of diabetes, CVD, or cancer., Results: We identified 832 deaths (246 from CVD) during 13.9 ± 7.0 years (mean ± SD) follow-up. Normal-weight individuals who were unfit (lowest one-third) had a higher risk of all-cause (hazard ratio 1.70 [95% CI 1.32-2.18]) and CVD (1.88 [1.13-3.10]) mortality compared with the normal-weight and fit (upper two-thirds) reference group in a model adjusted for age, sex, examination year, and multiple risk factors. The mortality risk for fit individuals who were overweight or obese did not differ significantly from the reference group. Similar patterns were observed for sex-specific thirds of waist circumference and % body fat., Conclusions: CRF markedly modifies the relationship between adiposity and mortality in persons with prediabetes. Unfit individuals have a higher and fit individuals have a lower mortality risk irrespective of adiposity level in this high-risk group.

Objective: Low cardiorespiratory fitness (CRF) is an independent risk factor for cardiovascular disease (CVD), especially in individuals with type 2 diabetes. Age-predicted, sex-stratified, and maximal MET cut points have been developed to determine the risk of CVD events and mortality in low CRF categories. We examined the proportion of Health Benefits of Aerobic and Resistance Training in Individuals With Type 2 Diabetes (HART-D) participants above these cut points before and after 9 months of aerobic training (AT), resistance training (RT), or a combination of both (ATRT)., Research Design and Methods: Participants from the HART-D study (n=196) who were randomly assigned to exercise training (AT, RT, or ATRT) or to a nonexercise control group between April 2007 and August 2009 were used in this ancillary study. Cut points were previously established for age-predicted METs (>100% and >85%, mean and increased CVD risk, respectively), age- and sex-stratified METs (Aerobic Center Longitudinal Study), and clinically discernible METs (men>8.0, women>6.5)., Results: Baseline prevalence of participants above these cut points was similar for all intervention groups (P>0.50) and ranged from 11.9% (>100% age predicted) to 55.1% (>85% age predicted). Baseline prevalence and age-, sex-, and race/ethnic group-adjusted percentage of participants above each cut point increased significantly after AT and ATRT (P<0.05 for all)., Conclusions: Structured exercise training, especially the AT component, was associated with a greater number of participants moving above established cut points indicative of low CRF. These results have public health and clinical implications for the growing number of patients with type 2 diabetes at high risk for CVD.

Objective: To investigate the associations between changes in body composition and fitness after exercise training and changes in hemoglobin A1c (HbA1c) in individuals with type 2 diabetes., Research Design and Methods: Participants (n = 201) were randomized to aerobic, resistance, or combined training for 9 months. HbA1c, waist circumference, total and trunk fat mass, appendicular fat mass, lean body mass, isokinetic leg muscle strength, peak O2 uptake, and estimated METs were assessed at baseline and follow-up. Change in HbA1c was evaluated across quartiles of change in body composition and fitness., Results: Change in HbA1c was associated with changes in body weight (r = 0.13, P = 0.052), waist circumference (r = 0.17, P = 0.013), trunk fat mass (r = 0.19, P = 0.005), and estimated METs (r = -0.16, P = 0.023). There was a trend in change in HbA1c across quartiles of waist circumference (P = 0.011), trunk fat mass (P = 0.020), and estimated METs (P = 0.011). Participants with increased estimated METs and reduced trunk fat mass had greater odds of having reduced HbA1c after training (3.48, 1.46-8.31). Finally, participants with increased estimated METs and reduced waist circumference were 2.81 (1.13-6.98) times more likely to have reduced HbA1c and type 2 diabetes medication use than those without improved fitness and central adiposity., Conclusions: In patients with type 2 diabetes, a reduction in central adiposity and increase in fitness were the most prominent predictors of the change in HbA1c in response to exercise training.

Objective: To investigate changes in body composition after 12 months of high-intensity progressive resistance training (PRT) in relation to changes in insulin resistance (IR) or glucose homeostasis in older adults with type 2 diabetes., Research Design and Methods: One-hundred three participants were randomized to receive either PRT or sham exercise 3 days per week for 12 months. Homeostasis model assessment 2 of insulin resistance (HOMA2-IR) and glycosylated hemoglobin (HbA1c) were used as indices of IR and glucose homeostasis. Skeletal muscle mass (SkMM) and total fat mass were assessed using bioelectrical impedance. Visceral adipose tissue, mid-thigh cross-sectional area, and mid-thigh muscle attenuation were quantified using computed tomography., Results: Within the PRT group, changes in HOMA2-IR were associated with changes in SkMM (r = -0.38; P = 0.04) and fat mass (r = 0.42; P = 0.02). Changes in visceral adipose tissue tended to be related to changes in HOMA2-IR (r = 0.35; P = 0.07). Changes in HbA1c were related to changes in mid-thigh muscle attenuation (r = 0.52; P = 0.001). None of these relationships were present in the sham group (P > 0.05). Using ANCOVA models, participants in the PRT group who had increased SkMM had decreased HOMA2-IR (P = 0.05) and HbA1c (P = 0.09) compared with those in the PRT group who lost SkMM. Increases in SkMM in the PRT group decreased HOMA2-IR (P = 0.07) and HbA1c (P < 0.05) compared with those who had increased SkMM in the sham group., Conclusions: Improvements in metabolic health in older adults with type 2 diabetes were mediated through improvements in body composition only if they were achieved through high-intensity PRT.

Objective: Whereas single assessments of cardiorespiratory fitness have been shown to predict lower incidence of type 2 diabetes, there are no data on long-term trends in fitness and risk. We investigated the relationship between long-term trends in fitness and the incidence of type 2 diabetes., Research Design and Methods: A cohort of 4,187 Japanese men free of diabetes completed annual health checkups and fitness tests for estimated maximal oxygen uptake at least four times over 7 years (1979-1985). We modeled the trend in fitness over 7 years for each man using simple linear regression. Men were then divided into quartiles based on the regression coefficient (slope) from the model. During the follow-up period (1985-1999), 274 men developed diabetes. Hazard ratios (HRs) and 95% CIs for the incidence of diabetes were obtained using the Cox proportional hazards model., Results: Men in the lowest quartile of the distribution decreased in fitness over the 7 years (median slope -1.25 ml/kg/min), whereas men in the highest quartile increased in fitness (median slope 1.33 ml/kg/min). With adjustment for age, initial fitness level, BMI, systolic blood pressure, cigarette smoking, alcohol intake, and a family history of diabetes and use of the lowest quartile, the HRs (95% CI) for the second through fourth quartiles were 0.64 (0.46-0.89), 0.40 (0.27-0.58), and 0.33 (0.21-0.50), respectively (P(trend) < 0.001)., Conclusions: These results indicate that the long-term trend in fitness is a strong predictor of the incidence of type 2 diabetes in Japanese men.

Objective: To examine cardiovascular disease (CVD) mortality risk in men with diabetes only, metabolic syndrome only, and concurrent metabolic syndrome and diabetes., Research Design and Methods: We examined CVD mortality risk by metabolic syndrome and diabetes status in men from the Aerobics Center Longitudinal Study (ACLS) (mean +/- SD age 45.1 +/- 10.2 years). Participants were categorized as having neither diabetes nor metabolic syndrome (n = 23,770), metabolic syndrome only (n = 8,780), diabetes only (n = 532), or both (n = 1,097). The duration of follow-up was 14.6 +/- 7.0 years with a total of 483,079 person-years of exposure and 1,085 CVD deaths., Results: Age-, examination year-, and smoking-adjusted CVD death rates (per 1,000 man-years) in men with neither metabolic syndrome nor diabetes, metabolic syndrome only, diabetes only, and both were 1.9, 3.3, 5.5, and 6.5, respectively. CVD mortality was higher in men with metabolic syndrome only (hazard ratio 1.8 [95% CI 1.5-2.0]), diabetes only (2.9 [2.1-4.0]), and both (3.4 [2.8-4.2]) compared with men with neither. The presence of metabolic syndrome was not associated (1.2 [0.8-1.7]) with higher CVD mortality risk in individuals with diabetes. In contrast, the presence of diabetes substantially increased (2.1 [1.7-2.6]) CVD mortality risk in individuals with metabolic syndrome., Conclusions: The presence of diabetes was associated with a threefold higher CVD mortality risk, and metabolic syndrome status did not modify this risk. Our findings support the fact that physicians should be aggressive in using CVD risk-reducing therapies in all diabetic patients regardless of metabolic syndrome status.

Objective: To examine how fitness in both childhood and adulthood is associated with adult obesity and insulin resistance., Research Design and Methods: A prospective cohort study set in Australia in 2004-2006 followed up a cohort of 647 adults who had participated in the Australian Schools Health and Fitness Survey in 1985 and who had undergone anthropometry and cardiorespiratory fitness assessment during the survey. Outcome measures were insulin resistance and obesity, defined as a homeostasis model assessment index above the 75th sex-specific percentile and BMI >or=30 kg/m(2), respectively., Results: Lower levels of child cardiorespiratory fitness were associated with increased odds of adult obesity (adjusted odds ratio [OR] per unit decrease 3.0 [95% CI 1.6-5.6]) and insulin resistance (1.7 [1.1-2.6]). A decline in fitness level between childhood and adulthood was associated with increased obesity (4.5 [2.6-7.7]) and insulin resistance (2.1 [1.5-2.9]) per unit decline., Conclusions: A decline in fitness from childhood to adulthood, and by inference a decline in physical activity, is associated with obesity and insulin resistance in adulthood. Programs aimed at maintaining high childhood physical activity levels into adulthood may have potential for reducing the burden of obesity and type 2 diabetes in adults.

Objective: The purpose of this study was to examine the associations of cardiorespiratory fitness (hereafter fitness) and various obesity measures with risks of incident impaired fasting glucose (IFG) and type 2 diabetes., Research Design and Methods: This was a prospective cohort study of 14,006 men (7,795 for the analyses of IFG), who did not have an abnormal electrocardiogram or a history of heart attack, stroke, cancer, or diabetes., Results: Of the men, 3,612 (39,610 person-years) and 477 (101,419 person-years) developed IFG and type 2 diabetes, respectively. Compared with the least fit 20% in multivariate analyses, IFG and type 2 diabetes risks in the most fit 20% were 14 and 52% lower, respectively (both P < 0.001). Men with BMI > or =30.0 kg/m2, waist girth >102.0 cm, or percent body fat > or =25 had 2.7-, 1.9-, and 1.3-fold higher risks for type 2 diabetes, respectively, compared with those for nonobese men (all P < 0.01), and the results for IFG were similar. In the combined analyses, obese unfit (least fit 20%) men had a 5.7-fold higher risk for type 2 diabetes compared with normal-weight fit (most fit 80%) men. We observed similar trends for the joint associations of BMI and fitness with IFG and those of waist girth or percent body fat and fitness with both IFG and type 2 diabetes., Conclusions: Low fitness and obesity increased the risks of IFG and type 2 diabetes by approximately similar magnitudes. When considered simultaneously, fitness attenuated but did not eliminate the increased risks of IFG and type 2 diabetes associated with obesity, and the highest risk was found in obese and unfit men.

Objective: The purpose of this article was to examine the risk of cancer mortality across levels of fitness and to examine the fitness-mortality relation for site-specific cancers in men with pre-diabetes and diabetes., Research Design and Methods: We examined the fitness-mortality relation for all-cause and site-specific cancer mortality among 18,858 men with pre-diabetes and 2,805 men with diabetes (aged 46.3 +/- 9.7 years [mean +/- SD]) from the Aerobics Center Longitudinal Study. We identified 719 cancer deaths during 354,558 person-years of risk. The duration of follow-up was 16.4 +/- 7.8 years (range <1-30.0 years)., Results: In men with pre-diabetes, moderate (hazard ratio 0.71 [95% CI 0.57-0.88]) and high fitness (0.76 [0.60-0.96]) were associated with lower risks of cancer mortality compared with the low-fit group in a model adjusted for age, examination year, smoking, alcohol use, fasting glucose concentration, previous cancer, and BMI. Similarly, for individuals with diabetes, moderate (0.53 [0.35-0.82]) and high fitness (0.44 [0.26-0.73]) were associated with lower risks of cancer mortality compared with the low-fit group. Among all men, being fit was associated with a lower risk of mortality from gastrointestinal (0.55 [0.39-0.77]), colorectal (0.53 [0.30-0.96]), liver (0.22 [0.07-0.71]), and lung cancer (0.43 [0.30-0.60])., Conclusions: In men with pre-diabetes and diabetes, higher levels of cardiorespiratory fitness were associated with lower risk of cancer mortality, particularly as a result of cancers of the gastrointestinal tract, compared with those who had low levels of fitness.

Objective: The purpose of this study was to determine the independent and joint associations of cardiorespiratory fitness (CRF) and BMI with the incidence of type 2 diabetes in women., Research Design and Methods: An observational cohort of 6,249 women aged 20-79 years was free of baseline cardiovascular disease, cancer, and diabetes. CRF was measured using a maximal treadmill exercise test. BMI was computed from measured height and weight. The incidence of type 2 diabetes was identified primarily by 1997 American Diabetes Association criteria., Results: During a 17-year follow-up, 143 cases of type 2 diabetes occurred. Compared with the least fit third, the multivariate (including BMI)-adjusted hazard ratio (HR) (95% CI) was 0.86 (0.59-1.25) for the middle third and 0.61 (0.38-0.96) for the upper third of CRF. For BMI, the multivariate (including CRF)-adjusted HR (95% CI) was 2.34 (1.55-3.54) for overweight individuals and 3.70 (2.12-6.44) for obese individuals, compared with normal-weight patients. In the combined analyses, overweight/obese unfit (the lowest one-third of CRF) women had significantly higher risks compared with normal-weight fit (the upper two-thirds of CRF) women., Conclusions: Low CRF and higher BMI were independently associated with incident type 2 diabetes. The protective effect of CRF was observed in individuals who were overweight or obese, but CRF did not eliminate the increased risk in these groups. These findings underscore the critical importance of promoting regular physical activity and maintaining normal weight for diabetes prevention.

Objective: To determine whether the associations between visceral adipose tissue (VAT), abdominal subcutaneous adipose tissue (ASAT), and the metabolic syndrome are altered depending on measurement site for VAT and ASAT and the definition used to identify the metabolic syndrome., Research Design and Methods: Total VAT and ASAT volume was derived using approximately 37 contiguous computed tomography (CT) images from T10-T11 to L5-S1 in 85 men. CT images obtained at eight intervertebral locations (e.g., L4-L5, L3-L4, etc.) were used to determine the associations between partial volumes (single images) and metabolic syndrome. Metabolic syndrome was defined using the National Cholesterol Education Program (NCEP) and International Diabetes Federation (IDF) criteria. Logistic regression was used to calculate the odds ratio (OR) per SD increase in adipose tissue., Results: For total and all partial volumes, VAT was more strongly associated with metabolic syndrome than ASAT independent of metabolic syndrome criteria. The OR (per SD) for NCEP metabolic syndrome was higher for total VAT volume (OR = 7.26) and for the partial volumes at T12-L1 (7.46) and L1-L2 (8.77) than those at the L4-L5 level (3.94). The OR for metabolic syndrome ( approximately 2.6) was not substantially different among the ASAT measures. A similar pattern of association was observed using the IDF metabolic syndrome criteria., Conclusions: The measurement site for VAT, but not for ASAT, has a substantial influence on the magnitude of the association with both metabolic syndrome definitions. However, because VAT remained significantly associated with metabolic syndrome regardless of measurement site, the clinical interpretation was unaltered by measurement protocol or metabolic syndrome definition.

Objective: Moderate to high levels of cardiorespiratory fitness (CRF) are associated with a lower risk of the metabolic syndrome and all-cause mortality. Unknown is whether CRF attenuates health risk for a given level of abdominal visceral fat, subcutaneous fat, and/or waist circumference., Research Design and Methods: The sample studied comprised 297 apparently healthy men with available computed tomography or magnetic resonance imaging scans of the abdomen, metabolic data, and maximal treadmill exercise test results. Men were categorized into low-CRF (20%, n = 56), moderate-CRF (40%, n = 94), and high-CRF (40%, n = 147) groups based on age and exercise test results. All analyses were adjusted for age., Results: For a given level of waist circumference, visceral fat, or subcutaneous fat, the high-CRF group had lower triglyceride levels (P < 0.05) and higher HDL cholesterol levels than the low- or moderate-CRF groups. There was a significant group interaction (P < 0.01) for blood pressure, indicating that the increase in blood pressure per unit increase in visceral fat or waist circumference was greater in men in the low-CRF group compared with the high-CRF group. The relative risks of having the metabolic syndrome were 1.8 (95% CI 1.0-3.1) and 1.6 (0.9-2.7) times higher in the low- and moderate-CRF groups, respectively, compared with the high-CRF group after adjusting for age, visceral fat, and subcutaneous fat (P for trend = 0.06)., Conclusions: High levels of CRF are associated with a substantial reduction in health risk for a given level of visceral and subcutaneous fat.

Objective: To quantify the relation of fitness to mortality among men with diabetes, adjusted for BMI and within levels of BMI., Research Design and Methods: In this observational cohort study, we calculated all-cause death rates in men with diabetes across quartiles of fitness and BMI categories. Study participants were 2,196 men with diabetes (average age 49.3 years, SD 9.5) who underwent a medical examination, including a maximal exercise test, during 1970 to 1995, with mortality follow-up to 31 December 1996., Results: We identified 275 deaths during 32,161 person-years of observation. Risk of all-cause mortality was inversely related to fitness. For example, in the fully adjusted model, the risk of mortality was 4.5 (2.6-7.6), 2.8 (1.6-4.7), and 1.6 (0.93-2.76) for the first, second, and third fitness quartiles, respectively, with the fourth quartile (highest fitness level) as the referent (P for trend <0.0001). There was no significant trend across BMI categories for mortality after adjustment for fitness. Similar results were found when the fitness-mortality relation was examined within levels of body composition. In normal-weight men with diabetes, the relative risks of mortality were 6.6 (2.8-15.0), 3.2 (1.4-7.0), and 2.2 (1.1-4.6) for the first, second, and third quartiles of fitness, respectively, as compared with the fourth quartile (P for trend <0.0001). We found similar results in the overweight and obese weight categories., Conclusions: There was a steep inverse gradient between fitness and mortality in this cohort of men with documented diabetes, and this association was independent of BMI.

Objective: To investigate the association between cardiorespiratory fitness and the incidence of type 2 diabetes among Japanese men., Research Design and Methods: This prospective cohort study was conducted in 4747 nondiabetic Japanese men, aged 20-40 years at baseline, enrolled in 1985 with follow-up to June 1999. Cardiorespiratory fitness was measured using a cycle ergometer test, and Vo(2max) was estimated. During a 14-year follow-up, 280 men developed type 2 diabetes., Results: The age-adjusted relative risks of developing type 2 diabetes across quartiles of cardiorespiratory fitness (lowest to highest) were 1.0 (referent), 0.56 (95% CI 0.42-0.75), 0.35 (0.25-0.50), and 0.25 (0.17-0.37) (for trend, P < 0.001). After further adjustment for BMI, systolic blood pressure, family history of diabetes, smoking status, and alcohol intake, the association between type 2 diabetes risk and cardiorespiratory fitness was attenuated but remained significant (1.0, 0.78, 0.63, and 0.56, respectively; for trend, P = 0.001)., Conclusions: These results indicate that a low cardiorespiratory fitness level is an important risk factor for incidence of type 2 diabetes among Japanese men.

Objective: Heart rate recovery (HRR) is an independent prognostic indicator for cardiovascular disease (CVD) and all-cause mortality in healthy men. We examined the association of HRR to CVD-related and all-cause mortality in men with diabetes., Research Design and Methods: In this cohort study we examined 2,333 men with documented diabetes (mean age 49.4 years) that had baseline 5-min HRR measurement following maximal exercise (heart rate(peak) - heart rate(5 min of recovery)) at The Cooper Clinic, Dallas, TX. We identified HRR quartiles as quartile 1 <55, quartile 2 55-66, quartile 3 67-75, and quartile 4 >75 bpm. Hazard ratios (HRs) for cardiovascular and all-cause death were adjusted for age, cardiorespiratory fitness, resting heart rate, fasting blood glucose, BMI, smoking habit, alcohol consumption, total cholesterol, triglyceride, and history of CVD at baseline., Results: During a median of 14.9 years follow-up, there were 142 deaths that were considered CVD related and 287 total deaths. Compared with men in the highest quartile of HRR, adjusted HRs in the first, second, and third quartiles were 2.0 (95% CI 1.1-3.8), 1.5 (0.8-2.7), and 1.5 (0.9-2.8), respectively, for cardiovascular death (P for trend < 0.001). Similarly, for all-cause death, adjusted HRs in the first, second, and third quartiles were 2.0 (1.3-3.2), 1.5 (1.0-2.3), and 1.5 (1.1-2.3) (P for trend < 0.001)., Conclusions: Among men with diabetes, a decreased HRR, even measured as long as 5 min after recovery, was independently predictive of cardiovascular and all-cause death.

Objective: To evaluate the relation between alcohol intake and incidence of type 2 diabetes., Research Design and Methods: This prospective study included 8,663 men with fasting plasma glucose measurements from at least two medical examinations. Alcohol intake was classified into five groups: nondrinkers and four quartiles (Qs) of drinkers according to the amount of alcohol intake. Type 2 diabetes was diagnosed by 1997 American Diabetes Association criteria., Results: There were 149 incident cases of type 2 diabetes during 52,588 person-years of follow-up. There was a U-shaped association between alcohol intake and diabetes, with the lowest incidence of diabetes at Q2 (61.9-122.7 g/week). As compared with Q2, men in Q3 and Q4 had a 2.2- (95% CI 1.2-3.9, P = 0.01) and 2.4-fold (1.4-4.4, P<0.01) risk of developing diabetes, while nondrinkers and men in Q1 had 1.8- (1.0-3.3, P<0.05) and 1.4-fold (0.7-2.6, P = 0.34) higher risk of diabetes, respectively. These associations persisted after adjustment for age, fasting plasma glucose, smoking, BMI, blood pressure, serum triglyceride concentration, cardiorespiratory fitness, HDL cholesterol, waist circumference, and parental diabetes., Conclusions: We observed an elevated risk of developing type 2 diabetes in nondrinkers and men with high alcohol intakes, when compared with men who reported moderate alcohol intake. Men with a high alcohol intake may be able to reduce their risk of developing type 2 diabetes if they drink less.

Objective: To determine the association of baseline cardiorespiratory fitness to all-cause mortality across the range of blood glucose levels., Research Design and Methods: Data from a prospective study of 8715 men (average age 42 yr), followed for an average of 8.2 yr (range 1-15 yr), were analyzed. Cardiorespiratory fitness was assessed by maximal-exercise treadmill testing. Men with evidence of clinical vascular disease or who did not achieve 85% of their age-predicted maximum heart rate during exercise testing were excluded from analyses., Results: Age-adjusted death rates increased with higher levels, of fasting blood glucose. Regardless of glycemic status, fit men had lower age-adjusted all-cause death rates than their less fit counterparts. For men with fasting blood glucose greater than or equal to 7.8 mM or physician-diagnosed non-insulin-dependent diabetes mellitus (NIDDM), the age-adjusted death rates per 10,000 person-yr of follow-up in unfit and fit subjects were 82.5 and 45.9, respectively. The age-adjusted relative risk of death due to all causes was significantly elevated in the lower-fitness group within each of three glycemic status levels: fasting blood glucose less than 6.4 mM; relative risk (RR) = 1.93 (95% confidence interval [95% CI] 1.15-3.26); fasting blood glucose 6.4-7.8 mM; RR = 3.42 (95% CI 2.27-5.15); and fasting blood glucose greater than or equal to 7.8 mM or with NIDDM, RR = 1.80 (95% CI = 1.25-2.58). Multivariate analyses, controlling for risk factors of mortality (age, resting systolic blood pressure, serum cholesterol, body mass index, family history of heart disease, follow-up interval, and smoking habit) showed a higher risk of death due to all causes for unfit compared with fit men. Multivariate risks of death associated with low fitness, compared with higher fitness (RR), in the three glycemic status groups were: fasting blood glucose less than 6.4 mM, RR = 1.38 (95% CI 1.09-1.74); fasting blood glucose 6.4-7.8 mM, RR = 1.61 (95% CI 0.91-2.86); and fasting blood glucose greater than or equal to 7.8 mM or with NIDDM, RR = 1.92 (95% CI 0.75-4.90).

There was a need to design a questionnaire that could accurately assess the activity patterns of Native Americans to evaluate the relationship between physical activity and diabetes. Such a questionnaire was developed and implemented into the data collection scheme of the prospective Pima Indian Study of Arizona. The questionnaire, which assesses historical, past-year, and past-week leisure and occupational activity, was examined in 29 Pima individuals aged 21-36 yr and was shown to be reliable with test-retest correlations (rank-order correlations ranged from 0.62 to 0.96 for leisure and occupational activity). Reproducibility of the past-year leisure physical-activity estimate was determined in 69 participants aged 10-59 yr and was found to be reliable in all age-groups with the exception of the 10- to 14-yr-old age-group (rank-order correlations were 0.31 in the 10- to 14-yr-old age-group compared to 0.88 to 0.92 in those greater than 20 yr of age). Validity of the current-activity section of the questionnaire was demonstrated indirectly through comparisons with activity monitors. The past-week leisure-activity estimate was related to the Caltrac activity monitor counts per hour (rho = 0.62, P less than 0.05, n = 17). In summary, a physical-activity questionnaire has been developed that is both reliable and feasible to use in the Pima Indian population to evaluate the relationship of physical activity to non-insulin-dependent diabetes mellitus.