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No abstract is provided for this article.

The aim of the HERITAGE Family Study was to investigate individual differences in response to a standardized endurance exercise program, the role of familial aggregation, and the genetics of response levels of cardiorespiratory fitness and cardiovascular disease and diabetes risk factors. Here we summarize the findings and their potential implications for cardiometabolic health and cardiorespiratory fitness. It begins with overviews of background and planning, recruitment, testing and exercise program protocol, quality control measures, and other relevant organizational issues. A summary of findings is then provided on cardiorespiratory fitness, exercise hemodynamics, insulin and glucose metabolism, lipid and lipoprotein profiles, adiposity and abdominal visceral fat, blood levels of steroids and other hormones, markers of oxidative stress, skeletal muscle morphology and metabolic indicators, and resting metabolic rate. These summaries document the extent of the individual differences in response to a standardized and fully monitored endurance exercise program and document the importance of familial aggregation and heritability level for exercise response traits. Findings from genomic markers, muscle gene expression studies, and proteomic and metabolomics explorations are reviewed, along with lessons learned from a bioinformatics-driven analysis pipeline. The new opportunities being pursued in integrative -omics and physiology have extended considerably the expected life of HERITAGE and are being discussed in relation to the original conceptual model of the study.

FTO is the strongest known genetic susceptibility locus for obesity. Experimental studies in animals suggest the potential roles of FTO in regulating food intake. The interactive relation among FTO variants, dietary intake and body mass index (BMI) is complex and results from previous often small-scale studies in humans are highly inconsistent. We performed large-scale analyses based on data from 177 330 adults (154 439 Whites, 5776 African Americans and 17 115 Asians) from 40 studies to examine: (i) the association between the FTO-rs9939609 variant (or a proxy single-nucleotide polymorphism) and total energy and macronutrient intake and (ii) the interaction between the FTO variant and dietary intake on BMI. The minor allele (A-allele) of the FTO-rs9939609 variant was associated with higher BMI in Whites (effect per allele = 0.34 [0.31, 0.37] kg/m2, P = 1.9 × 10−105), and all participants (0.30 [0.30, 0.35] kg/m2, P = 3.6 × 10−107). The BMI-increasing allele of the FTO variant showed a significant association with higher dietary protein intake (effect per allele = 0.08 [0.06, 0.10] %, P = 2.4 × 10−16), and relative weak associations with lower total energy intake (−6.4 [−10.1, −2.6] kcal/day, P = 0.001) and lower dietary carbohydrate intake (−0.07 [−0.11, −0.02] %, P = 0.004). The associations with protein (P = 7.5 × 10−9) and total energy (P = 0.002) were attenuated but remained significant after adjustment for BMI. We did not find significant interactions between the FTO variant and dietary intake of total energy, protein, carbohydrate or fat on BMI. Our findings suggest a positive association between the BMI-increasing allele of FTO variant and higher dietary protein intake and offer insight into potential link between FTO, dietary protein intake and adiposity.

OBJECTIVE: Age-related differences in body fat and, more specifically, in the accumulation of abdominal visceral adipose tissue (AT) were examined as potential covariates of the age-related difference in the metabolic profile predictive of cardiovascular disease (CVD) risk observed in young, as compared with middle-aged, premenopausal women. RESEARCH DESIGN AND METHODS: Body composition, AT distribution, plasma lipoprotein-lipid levels, glucose tolerance, and plasma insulin concentrations were assessed in a sample of 122 young women (27.4+/-7.5 years, mean +/- SD) and compared with a sample of 52 middle-aged premenopausal women (49.5+/-5.3 years) who still had a normal menstrual cycle. RESULTS: Middle-aged women were characterized by elevated levels of total abdominal and visceral AT and greater body fat mass and waist circumference, as well as by higher plasma levels of total cholesterol, LDL cholesterol, apolipoprotein (apo)B, and LDL-apoB compared with younger women. Furthermore, middle-aged women showed a greater glycemic response to a 75-g oral glucose load than young women (P < 0.01). In both young and middle-aged subjects, visceral AT accumulation was significantly correlated with plasma triglyceride, apoB, and LDL-apoB levels and with the cholesterol/HDL cholesterol ratio, as well as with plasma glucose, insulin, and C-peptide levels measured in the fasting state and after the oral glucose load, and negatively correlated with HDL cholesterol levels (-0.41 < or = r < or = 0.65, P < 0.05). When variables were adjusted for levels of visceral AT and fat mass, age-related differences that were initially found in plasma apoB and LDL-apoB levels, as well as in fasting glycemia and glucose tolerance, were eliminated. CONCLUSIONS: Results of the present study suggest that even before the onset of menopause there is an age-related deterioration in the metabolic risk profile and an increase in visceral AT deposition in middle-aged women compared with young control subjects. Furthermore, our results provide support for the notion that the age-related increase in visceral AT accumulation is a significant factor involved in the deterioration of the CVD risk profile noted in premenopausal women with age.

Ye, P.; Pérusse, L.; Símoneau, J.-A.; Boulay, M. R. FACSM; Lortie, G.; Bouchard, C. FACSM Author Information

Twenty-three male Black African and 23 male Caucasian subjects, ascertained as sedentary, participated in this study designed to determine whether there were differences in skeletal muscle histochemical and biochemical characteristics between racial groups. Muscle fiber type proportions (I, IIa, and IIb), fiber areas and activities of several enzyme markers of different energy metabolic pathways were determined from a biopsy of the vastus lateralis. Results indicated that Caucasians had a higher percent type I (8%, P less than 0.01) and a lower percent type IIa (6.7%, P less than 0.05) fiber proportions than Africans. No significant differences were observed between the two racial groups in the type IIb fiber proportion or in the three fiber type areas. Enzymes catalyzing reactions in phosphagenic [creatine kinase (CK)] and glycolytic [hexokinase (HK), phosphofructokinase (PFK), and lactate dehydrogenase (LDH)] metabolic pathways had significantly higher activities (about 30–40%) in the Black African group than in the Caucasian group (P less than 0.01). No significant difference was noted in the activities of oxidative enzymes [malate dehydrogenase (MDH), oxoglutarate dehydrogenase (OGDH), and 3-hydroxyacyl-CoA dehydrogenase (HADH)]. Consequently, the PFK/OGDH ratio was significantly elevated in Africans (P less than 0.05). The racial differences observed between Africans and Caucasians in fiber type proportion and enzyme activities of the phosphagenic and glycolytic metabolic pathways may well result from inherited variation. These data suggest that sedentary male Black individuals are, in terms of skeletal muscle characteristics, well endowed for sport events of short duration.

It has been previously proposed that the skeletal muscle fat content, as assessed by computed tomography (CT), was positively correlated with insulin resistance (Simoneau, J.A. et al., FASEB J, 273-278, 1995). In the present study, we have investigated the relationships between the area of mid-thigh muscle with a low CT attenuation level (LAM) (reflecting an increased fat content of the skeletal muscle) and the metabolic profile of a sample of 80 women aged between 25-55 years [BMI: 30.8 ± 8.7 kg/m2 (mean± SD)]. The LAM area was significantly correlated (p< 0.0001) with fat mass (FM; r= 0.82) and visceral adipose tissue area measured at L4-L5(VAT; r= 0.79). The LAM area was also significantly associated with plasma insulin and glucose levels measured in the fasting state and during a 75g oral glucose load (0.37 ≤ r ≤ 0.59; p< 0.001). Moreover, plasma lipid-lipoprotein levels as well as lipoprotein ratios were significantly correlated with the LAM area (-0.47 ≤ r ≤ 0.36; p< 0.05). Finally, LAM area was positively associated with systolic blood pressure (r= 0.37; p< 0.001) but not with diastolic blood pressure measured at rest. These results support the notion that the mid-thigh skeletal muscle fat content assessed by CT is a significant correlate of the features of the insulin resistant-dyslipidemic syndrome.

No abstract is provided for this article.

<h3>Objective</h3> To investigate the prevalence of distinct combinations of components of the metabolic syndrome among adolescents. <h3>Design</h3> A complex, multistage, stratified geographic area design for collecting representative data from the noninstitutionalized US population. <h3>Setting</h3> The NHANES, an ongoing surveillance of the nation's health conducted by the Centers for Disease Control and Prevention. <h3>Participants</h3> Two thousand four hundred fifty-six Hispanic, white, and black adolescents aged 12 to 19 years observed in the 2001-2002, 2003-2004, and 2005-2006 NHANES data releases. <h3>Main Outcome Measures</h3> Metabolic syndrome was defined as having 3 or more disorders in the following measurements: waist circumference, blood pressure, fasting triglycerides, high-density lipoprotein serum cholesterol, and glucose. <h3>Results</h3> About half of the participants had at least 1 disordered measurement, with an overall metabolic syndrome prevalence of 8.6% (95% confidence interval, 6.5%-10.6%). Prevalence was higher in males (10.8%) than females (6.1%), and in Hispanic (11.2%) and white (8.9%) individuals than in black individuals (4.0%). In black females, there was a high prevalence of a large waist circumference (23.3%), but no component of metabolic syndrome dominated its diagnosis in black adolescents of either sex. A large waist circumference and high fasting triglyceride and low high-density lipoprotein serum cholesterol concentrations were salient factors in Hispanic and white adolescents of both sexes; high glucose concentrations were prominent among Hispanic and white males. <h3>Conclusion</h3> The low prevalence of metabolic syndrome in black adolescents, in parallel with uniformly low prevalence of all 5 risk factors among those with metabolic syndrome, portend ethnic disparities in the time table for early onset of cardiometabolic disorders.

The objective of this cross-sectional study was to examine the association between sleep duration and alcohol consumption in adults (301 men and 402 women aged 18–64years) from the greater Quebec City area. Sleep duration (self-reported), alcohol consumption (3-day food record and questions on drinking habits), and disinhibition eating behavior trait (score⩾6 on the Three-Factor Eating Questionnaire) were assessed. Participants were categorized as short- (⩽6h), average- (7–8h) or long- (⩾9h) duration sleepers. Overall, short-duration sleepers consumed significantly more alcohol than the two other sleep-duration groups. After adjusting for relevant covariates, short sleep duration was associated with an increase in the odds of exceeding the recommendations for sensible weekly alcohol intake of 14 drinks for men and 7 drinks for women compared to those sleeping between 7 and 8h (OR 1.87, 95%CI 1.03–3.54, both sexes combined). In both men and women, daily alcohol intake was significantly higher in short-duration sleepers having a high disinhibition eating behavior trait. However, the prevalence of a binge drinking occasion (i.e. ⩾5 drinks on one occasion) was more common in men than women. Men sleeping less than 6h per night with a disinhibited eating behavior were more likely to report binge drinking (41% of them). In summary, the combination of short sleep duration with disinhibited eating behavior is associated with greater alcohol intake in adults.

There are strong genetic components to cardiorespiratory fitness and its response to exercise training. It would be useful to understand the differences in the genomic profile of highly trained endurance athletes of world class caliber and sedentary controls. An international consortium (GAMES) was established in order to compare elite endurance athletes and ethnicity-matched controls in a case-control study design. Genome-wide association studies were undertaken on two cohorts of elite endurance athletes and controls (GENATHLETE and Japanese endurance runners), from which a panel of 45 promising markers was identified. These markers were tested for replication in seven additional cohorts of endurance athletes and controls: from Australia, Ethiopia, Japan, Kenya, Poland, Russia and Spain. The study is based on a total of 1520 endurance athletes (835 who took part in endurance events in World Championships and/or Olympic Games) and 2760 controls. We hypothesized that world-class athletes are likely to be characterized by an even higher concentration of endurance performance alleles and we performed separate analyses on this subsample. The meta-analysis of all available studies revealed one statistically significant marker (rs558129 at GALNTL6 locus, p = 0.0002), even after correcting for multiple testing. As shown by the low heterogeneity index (I2 = 0), all eight cohorts showed the same direction of association with rs558129, even though p-values varied across the individual studies. In summary, this study did not identify a panel of genomic variants common to these elite endurance athlete groups. Since GAMES was underpowered to identify alleles with small effect sizes, some of the suggestive leads identified should be explored in expanded comparisons of world-class endurance athletes and sedentary controls and in tightly controlled exercise training studies. Such studies have the potential to illuminate the biology not only of world class endurance performance but also of compromised cardiac functions and cardiometabolic diseases.

In this research, methodology was developed to identify locations vulnerable to taste and odour problems in a distribution system. The methodology was based on a multicriteria procedure combining spatial information on consumer complaints and popular perception of tap water. The first step in the described methodology consisted of mapping complaints regarding tap water made by the population between 2002 and 2004 using a geographical information system (GIS). The second step consisted of analysing results of a questionnaire-based mail survey, also through GIS. The information generated using the above steps was integrated using a multicriteria and spatial approach allowing segregation of the distribution system into delineated zones, according to their vulnerability to occurrences of taste and odour problems. The identification of vulnerable sectors in a distribution system will help water managers to implement a better-targeted water quality monitoring programme--one that considers odours and tastes of drinking water--within the management process.