Felipe Lobelo

The Evolving Definition of ''Sedentary''

Studies that did not directly measure sedentary behavior often have been used to draw conclusions about the health effects of sedentariness. Future claims about the effects of sedentary, light, and moderate-to-vigorous activities on health outcomes should be supported by data from studies in which all levels of physical activity are differentiated clearly and measured independently.

Association between muscular strength and mortality in men: prospective cohort study

Objective To examine prospectively the association between muscular strength and mortality from all causes, cardiovascular disease, and cancer in men. Design Prospective cohort study. Setting Aerobics centre longitudinal study. Participants 8762 men aged 20-80. Main outcome measures All cause mortality up to 31 December 2003; muscular strength, quantified by combining one repetition maximal measures for leg and bench presses and further categorised as age specific thirds of the combined strength variable; and cardiorespiratory fitness assessed by a maximal exercise test on a treadmill. Results During an average follow-up of 18.9 years, 503 deaths occurred (145 cardiovascular disease, 199 cancer). Age adjusted death rates per 10 000 person years across incremental thirds of muscular strength were 38.9, 25.9, and 26.6 for all causes; 12.1, 7.6, and 6.6 for cardiovascular disease; and 6.1, 4.9, and 4.2 for cancer (all P<0.01 for linear trend). After adjusting for age, physical activity, smoking, alcohol intake, body mass index, baseline medical conditions, and family history of cardiovascular disease, hazard ratios across incremental thirds of muscular strength for all cause mortality were 1.0 (referent), 0.72 (95% confidence interval 0.58 to 0.90), and 0.77 (0.62 to 0.96); for death from cardiovascular disease were 1.0 (referent), 0.74 (0.50 to 1.10), and 0.71 (0.47 to 1.07); and for death from cancer were 1.0 (referent), 0.72 (0.51 to 1.00), and 0.68 (0.48 to 0.97). The pattern of the association between muscular strength and death from all causes and cancer persisted after further adjustment for cardiorespiratory fitness; however, the association between muscular strength and death from cardiovascular disease was attenuated after further adjustment for cardiorespiratory fitness. Conclusion Muscular strength is inversely and independently associated with death from all causes and cancer in men, even after adjusting for cardiorespiratory fitness and other potential confounders.

Uric Acid and the Development of Metabolic Syndrome in Women and Men

Associations between serum uric acid (UA) levels and metabolic syndrome (MetS) have been reported in cross-sectional studies. Limited information, however, is available concerning the prospective association of UA and the risk of developing MetS. The authors evaluated UA as a risk factor for incident MetS in a prospective study of 8429 men and 1260 women (aged 20-82 years) who were free of MetS and for whom measures of waist girth, resting blood pressure, fasting lipids, and glucose were taken during baseline and follow-up examinations between 1977 and 2003. Hyperuricemia was defined as >7.0 mg/dL in men and >6.0 mg/dL in women. Metabolic syndrome was defined with the National Cholesterol Education Program Adult Treatment Panel III criteria. The overall prevalence of hyperuricemia was 17%. During a mean follow-up of 5.7 years, 1120 men and 44 women developed MetS. Men with serum UA concentrations > or =6.5 mg/dL (upper third) had a 1.60-fold increase in risk of MetS (95% confidence interval, 1.34-1.91) as compared with those who had concentrations <5.5 mg/dL (lowest third). Among women, the risk of MetS was at least 2-fold higher for serum UA concentrations > or =4.6 mg/dL (P for trend = .02). Higher serum UA is a strong and independent predictor of incident MetS in men and women.

Physical activity habits of doctors and medical students influence their counselling practices

Doctors are well positioned to provide physical activity (PA) counselling to patients. They are a respected source of health-related information and can provide continuing preventive counselling feedback and follow-up; they may have ethical obligations to prescribe PA. Several barriers to PA counselling exist, including insufficient training and motivation of doctors and improvable, personal PA habits. Rates of exercise counselling by doctors remain low; only 34% of US adults report exercise counselling at their last medical visit. In view of this gap, one of the US health objectives for 2010 is increasing the proportion of patients appropriately counselled about health behaviours, including exercise/PA. Research shows that clinical providers who themselves act on the advice they give provide better counselling and motivation of their patients to adopt such health advice. In summary, there is compelling evidence that the health of doctors matters and that doctors’ own PA practices influence their clinical attitudes towards PA. Medical schools need to increase the proportion of students adopting and maintaining regular PA habits to increase the rates and quality of future PA counselling delivered by doctors.

Built environment attributes and walking patterns among the elderly population in Bogotá.

BACKGROUND There is increasing evidence that the built environment has an influence on physical activity; however, little is known about this relationship in developing countries. PURPOSE This study examined the associations between attributes of the built environment and walking patterns among the elderly. METHODS A multilevel cross-sectional study was conducted in 2007. Fifty neighborhoods were selected and 1966 participants aged > or =60 years were surveyed. Objective built environment measures were obtained in a buffer of 500 m using GIS. Environmental perceptions were assessed via questionnaire. RESULTS People who lived in areas with middle park area (4.53%-7.98% of land) were more likely to walk for at least 60 minutes during a usual week (prevalence OR [POR]=1.42, 95% CI=1.02, 1.98). Those who lived in areas with the highest connectivity index (1.81-1.99) were less likely to report walking for at least 60 minutes (POR=0.64, 95% CI=0.44, 0.93). Participants who reported feeling safe or very safe from traffic were more likely to report walking for at least 60 minutes (POR=1.50, 95% CI=1.11, 2.03). The presence of Ciclovía (recreational program) was marginally associated with having walked at least 150 minutes in a usual week (POR=1.29, 95% CI=0.97, 1.73). CONCLUSIONS This study showed that certain built and perceived environment characteristics were associated with walking among older adults living in Bogotá. Further studies should be conducted to better understand the potential influence of the built environment on physical activity among the elderly population in the context of Latin American cities.

Perceived and objective neighborhood environment attributes and health related quality of life among the elderly in Bogotá, Colombia

This study examines associations between neighborhood environment attributes and health related quality of life (HRQOL) and self-rated health (SRH) among older adults (60 years and over) in Bogotá, Colombia. Perceived and objective neighborhood environmental characteristics were assessed in a cross sectional multilevel design with 1966 older adults within 50 neighborhoods. Outcome variables included HRQOL (physical and mental dimensions) and SRH measured with the Spanish version of the Short Form 8 (SF-8). Independent variables included perceived and objective neighborhood characteristics as well as self-reported levels of walking. Hierarchical linear and logistic regression models were used for the analysis. Among perceived neighborhood characteristics, safety from traffic was positively associated with both HRQOL dimensions and SRH. Having safe parks was positively associated with the mental dimension of HRQOL and with SRH. Street noise was negatively associated with both HRQOL dimensions. Regarding objective neighborhood characteristics, residing in areas with more than eight percent of land covered by public parks was positively associated with SRH. Objective and perceived neighborhood characteristics could provide insight into potential interventions among older adults from rapidly urbanizing settings in Latin America.

The Exercise is Medicine Global Health Initiative: a 2014 update

Background A third of the worlds population does not engage in recommended levels of physical activity (PA), leading to substantial health and economic burdens. The healthcare sector offers a variety of resources that can help counsel, refer and deliver PA promotion programmes for purposes of primordial, primary, secondary and tertiary prevention. Substantial evidence already exists in support of multipronged PA counselling, prescription and referral strategies, in particular those linking healthcare and community-based resources. Methods The Exercise is Medicine (EIM) initiative was introduced in 2007 to advance the implementation of evidence-based strategies to elevate the status of PA in healthcare. In this article, we describe the evolution and global expansion of the EIM initiative, its components, their implementation, an evaluation framework and future initiative activities. Results Until now, EIM has a presence in 39 countries with EIM Regional Centers established in North America, Latin America, Europe, Africa, Southeast Asia, China and Australasia. The EIM Global Health Initiative is transitioning from its initial phase of infrastructure and awareness building to a phase of programme implementation, with an emphasis in low-to-middle income countries, where 80% of deaths due to non-communicable diseases already occur, but where a large gap in research and implementation of PA strategies exists. Conclusions Broad implementation of PA counselling and referral systems, as clinical practice standard of care, has the potential to improve PA at the population level by complementing and leveraging other efforts and to contribute to achieving global targets for the reduction of inactivity and related morbidity and mortality.

Validity of Cardiorespiratory Fitness Criterion-referenced Standards for Adolescents

PURPOSE The clinical utility of cardiorespiratory fitness (CRF) criterion-referenced standards (FITNESSGRAM) has not been tested in adolescents. We aimed to determine the ability of the FITNESSGRAM standards to discriminate between low and high cardiovascular disease (CVD) risk in a population-based sample of US adolescents. METHODS Participants included 1247 adolescents (45.7% females) aged 12-19 yr. A submaximal walking treadmill test was used to estimate peak oxygen consumption as a measure of CRF. Participants were dichotomized based on meeting or failing the sex- and age-specific FITNESSGRAM standards. CVD risk factors included systolic blood pressure, sum of triceps and subscapular skinfolds, homeostatic model assessment (HOMA) of insulin resistance, triglycerides, and total cholesterol/high-density lipoprotein ratio. A sex- and age-specific CVD risk score was computed as the mean of these five standardized risk factors. A risk score >1 SD was considered to indicate a high CVD risk. RESULTS One third of the adolescents fail to meet the FITNESSGRAM standards. Body fat and CVD risk score were significantly lower in adolescents meeting versus failing the FITNESSGRAM standards (all P < 0.003). Receiver operating characteristics curve analyses revealed that the CRF thresholds that best discriminated between low and high CVD risk were very similar to those established by FITNESSGRAM: 44.1 and 40.3 mL x kg(-1) x min(-1) among 12- to 15- and 16- to 19-yr-old boys and 36.0 and 35.5 mL x kg(-1) x min(-1) among 12- to 15- and 16- to 19-yr-old girls, respectively. CONCLUSIONS The CRF criterion-referenced standards established by FITNESSGRAM discriminate adolescents with a more favorable cardiovascular profile from those with a less favorable profile. Identification of children who fail to meet these standards can help detect the target population for pediatric CVD prevention strategies.

Muscular Strength and Adiposity as Predictors of Adulthood Cancer Mortality in Men

Background: We examined the associations between muscular strength, markers of overall and central adiposity, and cancer mortality in men. Methods: A prospective cohort study including 8,677 men ages 20 to 82 years followed from 1980 to 2003. Participants were enrolled in The Aerobics Centre Longitudinal Study, the Cooper Institute in Dallas, Texas. Muscular strength was quantified by combining 1-repetition maximal measures for leg and bench presses. Adiposity was assessed by body mass index (BMI), percent body fat, and waist circumference. Results: Cancer death rates per 10,000 person-years adjusted for age and examination year were 17.5, 11.0, and 10.3 across incremental thirds of muscular strength (P = 0.001); 10.9, 13.4, and 20.1 across BMI groups of 18.5-24.9, 25.0-29.9, and ≥30 kg/m2, respectively (P = 0.008); 11.6 and 17.5 for normal (<25%) and high percent body fat (≥25%), respectively (P = 0.006); and 12.2 and 16.7 for normal (≤102 cm) and high waist circumference (>102 cm), respectively (P = 0.06). After adjusting for additional potential confounders, hazard ratios (95% confidence intervals) were 1.00 (reference), 0.65 (0.47-0.90), and 0.61 (0.44-0.85) across incremental thirds of muscular strength, respectively (P = 0.003 for linear trend). Further adjustment for BMI, percent body fat, waist circumference, or cardiorespiratory fitness had little effect on the association. The associations of BMI, percent body fat, or waist circumference with cancer mortality did not persist after further adjusting for muscular strength (all P ≥ 0.1). Conclusions: Higher levels of muscular strength are associated with lower cancer mortality risk in men, independent of clinically established measures of overall and central adiposity, and other potential confounders. (Cancer Epidemiol Biomarkers Prev 2009;18(5):1468–76)

The cost of physical inactivity: moving into the 21st century

Physical inactivity is increasingly being recognised as a major problem in global health. The WHO estimates that 3.3 million people die around the world each year due to physical inactivity, making it the fourth leading underlying cause of mortality.1 Physical activity has beneficial effects on 23 diseases or health conditions.2 However, in most countries fewer than half of adults are active enough to reap most of these benefits.3 ,4 Given that inactivity increases the risk for many of the most costly medical conditions such as type 2 diabetes, stroke, ischaemic heart disease, falls and hip fractures, and depression, it is not surprising that physical inactivity has a substantial cost burden in addition to a large health burden. Despite impressive health and economic consequences, it is only recently that addressing physical inactivity has become a mainstream part of public health and health policy.5 However, this is clearly occurring. The WHO Global Action Plan for NCDs emphasises physical activity as an important element of primary and secondary prevention, WHO released a global recommendations for physical activity in 2010,6 the September 2011 United Nations General Assembly Summit on NCDs prominently include physical activity4 and national public health policy in influential countries such as Brazil and the USA substantively incorporates physical activity promotion.7 ,8 However, these are initial steps in addressing a global epidemic of NCDs and inactivity. The gap between the size of the problem and the scale of the public health response remains large. In such situations, effective advocacy is called for9 and often times this means economic data which highlight the costs of not taking action. This seems to be an argument for more and better analyses and research publications on the costs of physical inactivity. However, in the following paragraphs …