Michael D Schmidt

University of Tasmania, Hobart, Tasmania, Australia

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Publications (29)119.42 Total impact

  • Article: Physical Activity and Depression Symptom Profiles in Young Men and Women With Major Depression.
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    ABSTRACT: Objective This study explored whether young adults with major depression who are physically active differ in their depression symptom profile from those physically inactive.Methods Analyses included data from 950 (47.6%) men and 1045 women (mean [standard deviation] age = 31.5 [2.6] years) participating in a national study. Participants reported leisure physical activity (International Physical Activity Questionnaire) and ambulatory activity (pedometer steps per day). Diagnosis and symptoms of major depression were assessed using the Composite International Diagnostic Interview.ResultsPrevalence of major depression was 5.5% (n = 52) for men and 11.6% (n = 121) for women. Interactions between physical activity and sex were observed for depressed mood, appetite changes, vacillating thoughts, and suicidality (all, p < .050). Among those with major depression, physically active men were significantly less likely to endorse the presence of insomnia (prevalence ratio [PR] = 0.78, 95% confidence interval [CI] = 0.63-0.96), fatigue (PR = 0.82, 95% CI = 0.69-0.99), and suicidality (PR = 0.69, 95% CI = 0.49-0.96) compared with inactive men. Physically active women were significantly less likely to endorse hypersomnia (PR = 0.50, 95% CI = 0.27-0.95), excessive/irrational guilt (PR = 0.76, 95% CI = 0.59-0.97), vacillating thoughts (PR = 0.74, 95% CI = 0.58-0.95), and suicidality (PR = 0.43, 95% CI = 0.20-0.89) compared with inactive women. Associations were adjusted for age, physical health, educational attainment, depression severity, and other depressive symptoms.Conclusions Among adults with major depression, those physically active seem to differ in their depression symptom profile from those physically inactive.
    Psychosomatic Medicine 04/2013; · 3.97 Impact Factor
  • Article: A diagnosis of the metabolic syndrome in youth that resolves by adult life is associated with a normalization of high carotid intima-media thickness and type 2 diabetes mellitus risk: the bogalusa heart and cardiovascular risk in young Finns studies.
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    ABSTRACT: The aim of this study was to examine the effect of resolution from metabolic syndrome (MetS) between youth and adulthood on carotid artery intima-media thickness (IMT) and type 2 diabetes mellitus (T2DM). Published findings demonstrate that youth with MetS are at increased risk of cardio-metabolic outcomes in adulthood. It is not known whether this risk is attenuated in those who resolve their MetS status. Participants (n = 1,757) from 2 prospective cohort studies were examined as youth (when 9 to 18 years of age) and re-examined 14 to 27 years later. The presence of any 3 components (low high-density lipoprotein cholesterol, high triglycerides, high glucose, high blood pressure, or high body mass index) previously shown to predict adult outcomes defined youth MetS; the harmonized MetS criteria defined adulthood MetS. Participants were classified according to their MetS status at baseline and follow-up and examined for risk of high IMT and T2DM. Those with MetS in youth and adulthood were at 3.4 times the risk (95% confidence interval: 2.4 to 4.9) of high IMT and 12.2 times the risk (95% confidence interval: 6.3 to 23.9) of T2DM in adulthood compared with those that did not have MetS at either time-point, whereas those that had resolved their youth MetS status by adulthood showed similar risk to those that did not have MetS at either time-point (p > 0.20 for all comparisons). Although youth with MetS are at increased risk of adult high IMT and T2DM, these data indicate that the resolution of youth MetS by adulthood can go some way to normalize this risk to levels seen in those who have never had MetS.
    Journal of the American College of Cardiology 09/2012; 60(17):1631-9. · 14.16 Impact Factor
  • Article: Muscular fitness and clustered cardiovascular disease risk in Australian youth.
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    ABSTRACT: Low cardiorespiratory fitness (CRF) is a risk factor for cardiovascular disease (CVD) but the association of muscular fitness phenotypes (strength, endurance and power) on CVD risk in youth has not been examined. We examined the cross-sectional association between muscular fitness phenotypes with individual and clustered CVD risk factors and determined if any potential associations are independent of CRF. Participants were 1,642 youth aged 9, 12, and 15 years from the Australian Schools Health and Fitness Survey that had muscular strength (dynamometer), power (standing long-jump), and endurance (push-ups) as well as CRF (1.6 km run-time) measured. Outcomes included established risk factors (body mass index, waist circumference, blood lipids and blood pressure) and a clustered CVD risk-score. Muscular strength, endurance, and power were inversely associated with clustered CVD risk (all P < 0.05). After adjustment for body mass index, the association remained for muscular endurance and power (all P ≤ 0.001), but not strength. Muscular power was inversely related to prevalence of clustered CVD risk (≥80th percentile) within low (P trend < 0.001), moderate (Ptrend < 0.001), and high (Ptrend = 0.001) CRF categories. Among youth, low muscular fitness levels as well as low CRF should be avoided for primary CVD prevention.
    Arbeitsphysiologie 12/2011; 112(8):3167-71. · 2.15 Impact Factor
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    Article: Daily steps among Finnish adults: variation by age, sex, and socioeconomic position.
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    ABSTRACT: The aim of this study was to provide descriptive population-based pedometer data from adults aged 30-45 years in Finland, and to compare daily step counts with evidence-based indices. The data was collected from 1853 participants in 7 consecutive days in winter 2007-08 in part of 27-year follow up of the Cardiovascular Risk in Young Finns study. The participants took (mean±standard deviation) 7499 ± 2908 steps/day. Step counts included 1925 ± 2052 aerobic steps/day gathered in bouts of at least 10 min continuous ambulatory activity. Women had more total steps than men ((7824 ± 2925 vs. 7089 ± 2774; p < 0.001). Although participants had higher mean total steps on weekdays than on weekend days, they took more aerobic steps on weekend days than weekdays (p < 0.001). High-level non-manual work, and unemployment were associated with having fewer total steps, but high-level non-manual workers had more aerobic steps than other occupation groups. According to pedometer thresholds proposed by Tudor-Locke and Basset, 26% of men and 16% of women could be classified as inactive (<5000 steps/day) and 20% of women and 15% of men would be classified as active (>10,000 steps/day). We conclude that about one-quarter of men and one-fifth of women are considered as inactive, based on the number of daily total steps. Our results suggest that total steps may provide a very different picture of activity from aerobic steps; important differences are evident by socioeconomic position and day of the week.
    Scandinavian Journal of Public Health 09/2011; 39(7):669-77. · 1.39 Impact Factor
  • Article: Gait, gait variability and the risk of multiple incident falls in older people: a population-based study.
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    ABSTRACT: it is uncertain as to which measures of gait best predict those who are likely to fall. Our aim was to investigate the associations of gait and gait variability measures with incident falls risk. individuals aged 60-86 years (n = 412) were randomly selected from the Tasmanian electoral roll. Average gait and gait variability measures were collected on a computerised walkway. Falls were recorded prospectively over 12 months. Log multinomial regression was used to estimate the relative risk of single and multiple falls associated with gait measures. Covariates included age, sex, sensorimotor and cognitive measures, mood and medications. in this population-based study greater intra-individual variability in step length and double-support phase were linearly associated with increased risk of multiple falls (P = 0.04). Non-linear associations with multiple falls were found for gait speed P = 0.002, cadence P = 0.004 and step time variability P = 0.03. None of the gait measures predicted risk of single falls. there is an increased risk of multiple falls, but not single falls, in older people with poorer gait. Specific measures of gait and gait variability seem to confer this risk and may be amenable to interventions designed to reduce the risk of multiple falls in older people.
    Age and Ageing 07/2011; 40(4):481-7. · 3.09 Impact Factor
  • Article: Correlates of pedometer-measured and self-reported physical activity among young Australian adults.
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    ABSTRACT: Accurately quantifying physical activity is important for investigating relations with potential correlates, but past studies have mostly relied on self-report measures, which may be susceptible to error and biases, limiting interpretability. This study aimed to examine correlates of pedometer-determined physical activity and compare them with correlates of self-reported physical activity. Cross-sectional data were taken from 2017 Australian adults (aged 26-36 years) who were involved in the Childhood Determinants of Adult Health follow-up study during 2004-2006. Daily steps were recorded for seven days using Yamax pedometers and physical activity (total min/week) was reported via the long International Physical Activity Questionnaire. Demographic, biological, behavioral, psychological, social and environmental factors were assessed. Lower education, blue collar occupation and higher mental health score (men) and low-moderate alcohol intake (women) were positively associated with self-report and pedometer-measured activity. Among men, body mass index (BMI) was inversely and physical health score was positively associated with pedometer-measured activity while smoking, low to moderate alcohol intake, higher general health and urban area of residence were positively associated with self-reported activity. Among women, age and general health status were positively associated and number of live births inversely associated with pedometer-measured activity, while lower education, blue collar occupation, part time employment, smoking, diet, higher physical health score and higher mental health score were positively associated and white collar occupation inversely associated with self-reported activity. Many physical activity correlates differed depending on the measure employed; researchers should be mindful of these differences when selecting measures of physical activity.
    Journal of science and medicine in sport / Sports Medicine Australia. 05/2011; 14(6):496-503.
  • Article: Longitudinal associations of adiposity with adult lung function in the Childhood Determinants of Adult Health (CDAH) study.
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    ABSTRACT: Childhood BMI has been reported to be positively associated with adult lung function. The aim of this study was to investigate the effect of childhood BMI on young adult lung function independently of the effects of lean body mass (LBM). Clinical and questionnaire data were collected from 654 young Australian adults (aged 27-36 years), first studied when age 9, 12, or 15 years. Adult lung function was measured by forced vital capacity (FVC), forced expiratory volume in 1 s (FEV(1)), FEV(1)/FVC ratio, and the forced expiratory flow in the middle 50% of FVC (FEF(25-75)). BMI and LBM were derived from anthropometric measures at baseline (1985) and at follow-up (2004-2006). Multivariable models were used to investigate the effect of age and sex standardized BMI in childhood on adult lung function, before and after adjustment for LBM. Adult adiposity had a strong deleterious effect on lung function, irrespective of childhood BMI, and adjustment for childhood LBM eliminated any apparent beneficial effect of childhood BMI on adult FEV(1) or FVC. This suggests that the beneficial effect of increased BMI in childhood on adult FEV(1) and FVC observed in previous longitudinal studies is likely to be attributable to greater childhood LBM not adiposity. Obese children who become obese adults can expect to have poorer lung function than those who maintain healthy weight but large deficits in lung function are also likely for healthy weight children who become obese adults. This highlights the importance of lifetime healthy weight maintenance.
    Obesity 03/2011; 19(10):2069-75. · 4.28 Impact Factor
  • Article: Pediatric metabolic syndrome predicts adulthood metabolic syndrome, subclinical atherosclerosis, and type 2 diabetes mellitus but is no better than body mass index alone: the Bogalusa Heart Study and the Cardiovascular Risk in Young Finns Study.
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    ABSTRACT: The clinical utility of identifying pediatric metabolic syndrome (MetS) is controversial. This study sought to determine the status of pediatric MetS as a risk factor for adult subclinical atherosclerosis (carotid intima-media thickness [cIMT]) and type 2 diabetes mellitus (T2DM) and compare and contrast this prediction with its individual components. Using data from the population-based, prospective, observational Bogalusa Heart and Cardiovascular Risk in Young Finns studies, we examined the utility of 4 categorical definitions of youth MetS and their components in predicting adult high cIMT and T2DM among 1781 participants aged 9 to 18 years at baseline (1984 to 1988) who were then examined 14 to 27 years later (2001-2007) when aged 24 to 41 years. Youth with MetS were at 2 to 3 times the risk of having high cIMT and T2DM as adults compared with those free of MetS at youth. Risk estimates with the use of high body mass index were similar to those of MetS phenotypes in predicting adult outcomes. Comparisons of area under the receiver operating characteristic curve and net reclassification index suggested that prediction of adult MetS, high cIMT, and T2DM in adulthood with the use of youth MetS was either equivalent or inferior to classification based on high body mass index or overweight and obesity. Youth with MetS are at increased risk of meaningful adult outcomes; however, the simplicity of screening for high BMI or overweight and obesity in the pediatric setting offers a simpler, equally accurate alternative to identifying youth at risk of developing adult MetS, high cIMT, or T2DM.
    Circulation 10/2010; 122(16):1604-11. · 14.74 Impact Factor
  • Article: Physical activity and its association with cardiovascular risk factors in Vietnam.
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    ABSTRACT: This study examined physical activity in leisure time and at work as estimated by the Global Physical Activity Questionnaire (GPAQ) and the associations between both total and domain-specific physical activity with cardiovascular risk factors in a population-based Vietnamese sample. Participants (n = 1978) were 25- to 64-year-old adults selected by stratified multistage sampling. Leisure activity contributed to <5% of total moderate and vigorous activity and was not associated with cardiovascular risk factors. Total moderate and vigorous activity was associated with body composition (r = -0.16 to -0.22; P < .001), blood glucose (r = -0.07; P < .05), and total cholesterol (r = -0.17; P < .001) for men and with total cholesterol (r = -0.07; P < .05) for women after adjusting for age. Further adjustment for smoking and alcohol intake made negligible changes. These associations were largely driven by work activity, which accounted for 80% of total activity.
    Asia-Pacific Journal of Public Health 09/2010; 24(2):308-17. · 1.06 Impact Factor
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    Article: Ageing and gait variability--a population-based study of older people.
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    ABSTRACT: gait variability may be an important predictor of falls risk, but its characteristics are poorly understood. to examine the relationship between age and gait variability in a population-based sample of older people. cross-sectional study. in people aged 60-86 years (n = 412), temporal and spatial gait variability measures were recorded with a GAITRite walkway. Regression analysis was used to model the relationship between age and gait variability adjusting for height, weight and self-reported chronic disease. Further adjustment was made for gait speed to examine its influence on the associations. older age was associated with greater variability (P < 0.05) in all gait measures. All relationships were linear, except that between age and step time variability, which was curvilinear in women. Adjusting for gait speed changed the magnitude of the age coefficient by 62-86% for temporal variability measures, 25% for step length variability and 5-12% for step width variability. age is linearly associated with greater intra-individual gait variability for most gait measures, except for step time variability in women. Gait speed may mediate the association between age and temporal variability measures. Further study is needed to understand the factors responsible for the greater gait variability with ageing.
    Age and Ageing 03/2010; 39(2):191-7. · 3.09 Impact Factor
  • Article: Sensorimotor factors affecting gait variability in older people--a population-based study.
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    ABSTRACT: Intra-individual gait variability predicts falls and disability in older people. Knowledge of factors that contribute to gait variability may lead to interventions aimed at reducing decline in mobility and falls risk. The aim of this population-based study was to examine whether poorer performance on a range of sensorimotor measures was associated with greater gait variability. Individuals aged 60-86 years (n = 412) were randomly selected from the Southern Tasmanian electoral roll. Spatial (step length and step width) and temporal (step time and double support time [DST]) gait measures were recorded with a GAITRite walkway. Variability for each gait measure was the standard deviation of measurements recorded during six walks. Sensorimotor measures included visual contrast sensitivity, lower limb proprioception, quadriceps strength, reaction time, and body sway (eyes open and closed). Regression analysis was used to determine the relationships between sensorimotor measures and gait variability. Greater sway on a foam mat (eyes closed) was associated with greater variability in all gait measures (p < .05). Slower reaction time was associated with greater variability in both temporal gait measures (p < .05), whereas poorer proprioception was only associated with greater DST variability (p = .01) and weaker quadriceps strength with greater step time variability. Other sensorimotor factors were not independently associated with gait variability. Body sway, reaction time, quadriceps strength, and proprioception are likely factors that may explain gait variability in the general older population. Further research is warranted to determine causality of these associations and whether intervention programs addressing these factors may reduce gait variability in older people.
    The Journals of Gerontology Series A Biological Sciences and Medical Sciences 11/2009; 65(4):386-92. · 4.60 Impact Factor
  • Article: Cardiometabolic risk in younger and older adults across an index of ambulatory activity.
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    ABSTRACT: Pedometers are increasingly being used to assess population levels of physical activity and as motivational tools for individuals to increase their physical activity. To maximize their utility, a framework for classifying pedometer-determined activity into meaningful health-related categories is needed. This study investigated whether a pedometer step index proposed by Tudor-Locke and Bassett can effectively group younger and older adults according to cardiometabolic health status. Analyses (conducted in 2008) used cross-sectional data from the Childhood Determinants of Adult Health study (1793 adults aged 26-36 years; collected 2004-2006) and from the Tasmanian Older Adult Cohort study (1014 adults aged 50-80 years; collected 2002-2006). Participants wore a pedometer for 7 days and the prevalence of cardiometabolic health indicators, including the metabolic syndrome, elevated Pathobiological Determinants of Atherosclerosis in Youth risk scores, and elevated Framingham risk scores, was examined across the following step categories: sedentary (< 5000); low-active (5000-7499); somewhat active (7500-9999); active (10,000-12,499); and high-active (> or = 12,500). With the exception of younger men, individuals achieving > or = 5000 steps had a substantially lower prevalence of adverse cardiometabolic health indicators than those obtaining fewer steps. Differences in the prevalence of adverse indicators were generally modest across higher steps-per-day categories. However, younger men and women in the high-active category had a substantially lower prevalence of some adverse health indicators. In general, the proposed index for classifying pedometer activity effectively distinguishes cardiometabolic health risk. Pedometers may be a useful tool for objectively identifying inactive individuals at greatest risk for poor cardiometabolic health.
    American journal of preventive medicine 10/2009; 37(4):278-84. · 4.24 Impact Factor
  • Article: A population-based study of sensorimotor factors affecting gait in older people.
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    ABSTRACT: the study of factors associated with age-related gait decline may assist in developing methods to preserve mobility in older people. to examine the associations between sensorimotor factors relevant to ageing and gait in the general older population. cross-sectional population-based study. participants aged 60-86 years (n = 278) were randomly selected using electoral roll sampling. Sensorimotor factors (quadriceps strength, reaction time, postural sway, proprioception and visual contrast sensitivity) were measured using the Physiological Profile Assessment. Gait variables (speed, cadence, step length, double support phase and step width) were recorded with a GAITRite walkway. Linear regression was used to model relationships between sensorimotor and gait variables. mean age of participants was 72.4 (7.0) years with 154 (55%) males. Better quadriceps strength, reaction time and postural sway (in men) predicted faster gait speed due to their effects on step length and/or cadence. Body weight (in men) and visual contrast sensitivity (in women) were modifying factors in these relationships. Better postural sway, reaction time (in men) and quadriceps strength (in women) predicted reduced double support phase. Modifying factors were quadriceps strength (in men) and proprioception (in women). Postural sway was the sole predictor of step width and in women only. potentially modifiable sensorimotor factors were associated with a range of gait measures, with a different pattern of individual associations and interactions seen between the sexes. These results provide further mechanistic insights towards explaining age-related gait decline in the general older population.
    Age and Ageing 04/2009; 38(3):290-5. · 3.09 Impact Factor
  • Article: Physical activity and depression in young adults.
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    ABSTRACT: Epidemiologic research suggests that physical activity is associated with decreased prevalence of depression. However, the relationship between physical activity accumulated in various domains and depression remains unclear. Further, previous population-based studies have predominantly utilized self-reported measures of physical activity and depression symptom subscales. Associations between physical activity in various domains (leisure, work, active commuting, yard/household) and depression were examined using both subjective and objective measures of physical activity and a diagnostic measure of depression. Analyses (conducted in 2007) included data from 1995 young adults participating in a national study (2004-2006). Physical activity was measured by self-report (International Physical Activity Questionnaire) and objectively as pedometer steps/day. Depression (DSM-IV 12-month diagnosis of major depression or dysthymic disorder) was assessed using the Composite International Diagnostic Interview. For women, moderate levels of ambulatory activity (>or=7500 steps/day) were associated with approximately 50% lower prevalence of depression compared with being sedentary (<5000 steps/day) (p trend=0.005). Relatively low durations of leisure physical activity (>or=1.25 hours/week) were associated with approximately 45% lower prevalence compared with the sedentary group (0 hours/week) (p trend=0.003). In contrast, high durations of work physical activity (>or=10 hours/week) were associated with an approximate twofold higher prevalence of depression compared with being sedentary (0 hours/week) (p trend=0.005). No significant associations were observed for steps/day in men or for other types of self-reported activity including total physical activity in both men and women. These findings indicate that the context in which physical activity is assessed and the measurement methods utilized are important considerations when investigating associations between physical activity and depression.
    American journal of preventive medicine 01/2009; 36(2):161-4. · 4.24 Impact Factor
  • Article: Obesity and menstrual irregularity: associations with SHBG, testosterone, and insulin.
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    ABSTRACT: This cross-sectional study aimed to examine the association between different body composition measures, menstrual cycle characteristics, and hormonal factors in a population-based sample of young women. The study sample included 726 Australian women aged 26-36 years who were not currently taking hormonal contraceptives and were not currently pregnant or breast feeding. Anthropometric measures included BMI, waist circumference (WC), and waist-hip ratio (WHR). Menstrual cycle characteristics were self-reported and usual cycles defined as short (<or=25 days), normal (26-34 days), or long (>or=35 days). Cycles were defined as irregular if there were >or=15 days between the longest and shortest cycle in the past 12 months. Fasting serum levels of sex hormone-binding globulin (SHBG), testosterone, insulin, and glucose were measured and the free androgen index (FAI) derived. Compared with those of normal weight, obese women had at least a twofold greater odds of having an irregular cycle, whether defined by BMI (odds ratio (OR) = 2.61; 95% CI = 1.28-5.35), WC (OR 2.28; 95% CI = 1.16-4.49), or WHR (OR = 2.27; 95% CI = 1.09-4.72). Body composition measures were significantly positively associated with fasting insulin, testosterone, and FAI, and negatively associated with SHBG (P < 0.01). Fasting insulin, SHBG, and FAI had the strongest influence on the associations between obesity and irregular cycles, with statistically significant ORs of having an irregular cycle being attenuated to near null values following adjustment. In conclusion, both overall and central obesity were significantly associated with having an irregular menstrual cycle. This association was substantially influenced by hormonal factors, particularly insulin and SHBG.
    Obesity 01/2009; 17(5):1070-6. · 4.28 Impact Factor
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    Article: Decline in physical fitness from childhood to adulthood associated with increased obesity and insulin resistance in adults.
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    ABSTRACT: To examine how fitness in both childhood and adulthood is associated with adult obesity and insulin resistance. 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. 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. 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.
    Diabetes care 12/2008; 32(4):683-7. · 8.09 Impact Factor
  • Article: Physical activity and gestational diabetes mellitus among Hispanic women.
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    ABSTRACT: Studies in predominantly non-Hispanic white populations have suggested that physical activity during pregnancy is associated with a reduced risk of gestational diabetes mellitus (GDM). There are few such studies in Hispanic women, a group at increased risk for GDM. We conducted a prospective cohort study of household/caregiving, occupational, sports/exercise, and active living habits and the risk of GDM among 1006 Hispanic (predominantly Puerto Rican) prenatal care patients in western Massachusetts from 2000 to 2004. Prepregnancy, early pregnancy, and midpregnancy physical activity was assessed using the Kaiser Physical Activity Survey. A total of 33 women (3.3%) were diagnosed with GDM, and 119 women (11.8%) were diagnosed with abnormal glucose tolerance. There were no significant associations between GDM risk and occupational and active living activities in prepregnancy, early pregnancy, and midpregnancy or with a change in levels of household/caregiving, occupational, and active living activities from prepregnancy to during pregnancy. However, after controlling for age and prepregnancy body mass index (BMI), women in the highest quartile of prepregnancy (OR = 0.2, 95% CI 0.1-0.8, p(trend) = 0.03) and midpregnancy (OR = 0.2, 95% CI 0.1-0.8, p(trend) = 0.004) household/caregiving activities as well as midpregnancy sports/exercise (0.1, 95% CI 0.0-0.7, p(trend) = 0.12) had a reduced risk of GDM compared with women in the lowest quartile. Findings in this Hispanic population, although based on small numbers of cases, are consistent with prior research among predominantly non-Hispanic white populations.
    Journal of Women s Health 07/2008; 17(6):999-1008. · 1.57 Impact Factor
  • Article: Predictors of excessive and inadequate gestational weight gain in Hispanic women.
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    ABSTRACT: Factors influencing gestational weight gain are incompletely understood, particularly among Hispanic women. We assessed medical, sociodemographic, behavioral, and psychosocial predictors of overall gestational weight gain, as well as gains below, within, or above the range recommended by the Institute of Medicine (IOM) within a prospective study of 770 Hispanic (predominantly Puerto Rican) prenatal care patients at a large tertiary care facility in Western Massachusetts. One third of women gained within the recommended range, 22% gained below, and 45% gained above the range. In multivariate analysis, women in the highest category of BMI (P(trend)<0.001) and parity (P(trend)<0.001) gained on average 9 lbs less than those in the lowest category. Increasing time in residence in the continental United States (P(trend)<0.01) as well as a number of prenatal care visits (P(trend)=0.03) were positively associated with weight gain. Overweight women (odds ratio (OR)=2.2, 95% confidence interval (CI) 1.3, 3.8) and those over age 30 years (OR=2.5, 95% CI 1.2, 5.0) were more likely to gain above the IOM range as compared to normal-weight women and those aged 20-24, respectively. Women with <10 years of residence in the United States were 50% less likely to gain above the IOM range as compared to third-generation women (95% CI 0.3, 0.9). Findings identify determinants of gestational weight gain which can form the basis of targeted interventions in this rapidly growing ethnic group.
    Obesity 07/2008; 16(7):1657-66. · 4.28 Impact Factor
  • Article: A comparison of subjective and objective measures of physical activity and fitness in identifying associations with cardiometabolic risk factors.
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    ABSTRACT: To compare the ability of alternative measures of physical activity and fitness to quantify associations with health outcomes. Associations between a range of subjective and objective physical activity and fitness measures and cardiometabolic risk factors were examined using data from 1,631 Australians aged 26-36 years. Anthropometry, fitness, blood pressure, and fasting blood glucose, insulin, and lipids were measured at study clinics. Participants completed the International Physical Activity Questionnaire (IPAQ) and 7-day pedometer diaries; they also reported sedentary behavior (sitting, television viewing). In men and women, associations were strongest for fitness, with those in the highest (vs. lowest) fitness quarter having a 75% to 80% lower prevalence of two or more primary risk factors (waist circumference, high-density lipoprotein cholesterol, and insulin resistance). In men, a 60% to 70% reduced prevalence of two or more risk factors was observed across extreme quarters of IPAQ leisure, IPAQ vigorous, sitting duration, and pedometer measures. Similar reductions in prevalence were observed only across extreme quarters of pedometer activity and television viewing in women. Associations between alternative measures and cardiometabolic risk were relatively independent, suggesting that a range of physical activity and fitness measures may be needed to most accurately quantify associations between physical activity and health.
    Annals of epidemiology 06/2008; 18(5):378-86. · 2.95 Impact Factor
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    Article: Television viewing and abdominal obesity in young adults: is the association mediated by food and beverage consumption during viewing time or reduced leisure-time physical activity?
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    ABSTRACT: The behavioral pathways through which television (TV) viewing leads to increased adiposity in adults are unclear. We wanted to determine whether the association between TV viewing and abdominal obesity in young adults is mediated by food and beverage consumption during TV viewing time or by a reduction in overall leisure-time physical activity (LTPA). This study involved a cross-sectional analysis of data from 2001 Australian adults aged 26-36 y. Waist circumference (WC) was measured at study clinics, and TV viewing time, frequency of food and beverage consumption during TV viewing, LTPA, and demographic characteristics were self-reported. Women watching TV > 3 h/d had a higher prevalence of severe abdominal obesity (WC: > or = 88 cm) compared with women watching < or = 1 h/d [prevalence ratio (PR): 1.89; 95% CI: 1.32, 2.71]. Moderate abdominal obesity (WC: 94-101.9 cm) was more prevalent in men watching TV > 3 h/d than in men watching < or = 1 h/d (PR: 2.16; 95% CI: 1.37, 3.41). Adjustment for LTPA made little difference, but adjustment for food and beverage consumption during TV viewing attenuated the associations (PR: 1.48; 95% CI: 1.01, 2.17 for women; PR: 1.73; 95% CI: 1.06, 2.83 for men). The association between TV viewing and WC in young adults may be partially explained by food and beverage consumption during TV viewing but was not explained by a reduction in overall LTPA. Other behaviors likely contribute to the association between TV viewing and obesity.
    American Journal of Clinical Nutrition 05/2008; 87(5):1148-55. · 6.67 Impact Factor

Institutions

  • 2006–2012
    • University of Tasmania
      • Menzies Research Institute
      Hobart, Tasmania, Australia
  • 2011
    • Jyväskylän yliopisto
      • Department of Sport Sciences
      Jyväskylä, Western Finland, Finland
    • Monash University
      • Department of Medicine
      Melbourne, Victoria, Australia
    • Deakin University
      • Centre for Physical Activity and Nutrition Research
      Geelong, Victoria, Australia
  • 2010
    • University of Turku
      • Research Centre of Applied and Preventive Cardiovascular Medicine
      Turku, Western Finland, Finland
    • University of Georgia
      • Department of Kinesiology
      Athens, GA, USA
  • 2008
    • The Royal Children's Hospital
      Melbourne, Victoria, Australia
    • Menzies Research Institute
      Hobart, Tasmania, Australia
  • 2003–2008
    • University of Massachusetts Amherst
      • • Department of Public Health
      • • Division of Biostatistics and Epidemiology
      Amherst Center, MA, USA