Top PDF Association of sedentary time with mortality independent of moderate to vigorous physical activity.

Association of sedentary time with mortality independent of moderate to vigorous physical activity.

Association of sedentary time with mortality independent of moderate to vigorous physical activity.

cholesterol, and other metabolic risk factors) [19]. Furthermore, sedentary behavior has been recently associated with mitochon- drial dysfunction, dysregulation of cellular redox status and increased inflammation in older sedentary adults compared to more active adults [20]. Sedentary behavior in addition to aging seems thereby associated with reduced mitochondrial biogenesis and increased electron leak from the mitochondrial electron transport chain which exposes the skeletal muscle intracellular milieu to increased reactive oxygen species – mediated toxicity and altered mitochondrial DNA deletions and mutations. Ultimately, this chain of events leads to accelerated cellular senescence and cell death [20]. Nevertheless, more research is warranted into the mechanisms underlying the adverse health effects of sedentariness. An important strength of our study was that sedentary behavior was measured objectively with accelerometry. However, accel- erometers are not sensitive to detect all activities such as standing still, upper body movements and biking. Use of an accelerometer definition of MVPA based on studies of primarily younger adults may lead to an underestimate of MVPA for older adults due to the decline in exercise capacity with age, which may lead to residual confounding. Similarly, while the cutpoint we used to define sedentary time has been evaluated for validity [17], it is possible that the accuracy of this threshold varies in different age groups. However, small variations in the cut-point selected (e.g., 50, 100, 150 counts per minute) would not be likely to affect the classification of individuals into quartiles of sedentary time. Thus, our results are unlikely to be affected by the cutpoint chosen to define sedentary time. We adjusted our analyses for a wide range of potential confounding variables, we can however not exclude that other unknown or unmeasured factors may account for some of the reported associations. The follow-up time of our study was short which may increase the risk of reverse causation. However, to address this issue, in separate models we excluded individuals with mobility limitation, pre-existing disease, and early deaths and the positive association between sedentary time and mortality remained. Further studies with longer mortality follow-up are needed to corroborate our findings. Larger studies will also enable us to evaluate the joint or synergistic effects of sedentary time and time spent in physical activities of different intensities on adverse health outcomes. Also, future studies examining the effect of different cutpoints to control for physical activity would be instructive.
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Rev. bras. cineantropom. desempenho hum.  vol.19 número2

Rev. bras. cineantropom. desempenho hum. vol.19 número2

Abstract – he aim of this study was to analyze the contribution of physical activity (PA) and sedentary time (ST) to Body Mass Index (BMI) in adults. he study was conducted in 2009, in Curitiba, Parana, Brazil with adults aged 18-65 years (1,411). A multidimen- sional questionnaire was used in which BMI, weekly minutes of PA and ST were obtained from self-reports. PA and ST were combined to determine the following independent variables: a) “active and not sedentary”; b) “active and sedentary”; c) “not active and not sedentary” and d) “not active and sedentary”. Multinomial logistic regressions were used to test the associations between PA, ST and BMI. he adjusted regression model showed that PA, regardless of ST, lowered the likelihood of participants being classiied as obese by 34% and 55%, respectively. In addition, PA at recommended levels (≥150 minutes/ week), while not being sedentary, lowered by 85% the likelihood of being classiied in the underweight category. Finally, ≥10 minutes/week of PA, while reporting higher ST levels, reduced the likelihood of being classiied as overweight by 37%. PA is associated with BMI regardless of TS. In addition, PA at recommended levels is inversely related to obesity and overweight.
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The contribution of former work-related activity levels to predict physical activity and sedentary time during early retirement: moderating role of educational level and physical functioning.

The contribution of former work-related activity levels to predict physical activity and sedentary time during early retirement: moderating role of educational level and physical functioning.

Consequently, the first aim of this study was to examine if former work-related sitting, standing, walking or vigorous activities predict physical activity and sedentary time during early retirement. Secondly, we examined the moderating effects of educational level and physi- cal functioning on these associations. Educational level, as a proxy for socio-economic status (SES) was included as a moderator because individuals of higher SES probably have more fi- nancial resources to support physical activities after retirement [18], which may affect the ex- amined associations. Physical functioning was included as a moderator because functional limitations are a prominent problem in ageing people, that needs to be taken into account when physical activity and sedentary time are examined [19]. Very specific physical activity measures (transport-related walking and cycling, leisure-time walking and cycling, and leisure- time moderate-to-vigorous physical activity (MVPA) were examined as outcome measures, be- cause previous research showed that determinants are very behavior-specific [20]. Further- more, functional limitations are probably more important in the relationship with MVPA or cycling than with walking.
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Rev. bras. cineantropom. desempenho hum.  vol.13 número5 en a05v13n5

Rev. bras. cineantropom. desempenho hum. vol.13 número5 en a05v13n5

Abstract – The aim of the present study was to characterize bone mineral density (BMD) and content (BMC) in Brazilian adolescent girls according to age and pubertal stage. A total of 329 girls ranging in age from 10 to 20 years participated in this study. Body weight, height, body mass index, pubertal stage, race, daily calcium intake, and time spent per week performing moderate- to vigorous-intensity physical activity (MVPA) were evaluated. Lumbar spine and femoral neck BMD and BMC were assessed by dual-energy x-ray absorp- tiometry. One-way ANOVA with Tukey post-hoc test was used to identify differences in bone mass between ages and pubertal stages (p≤0.05). The daily calcium intake reported by the adolescents was inadequate, corresponding to only 26-47% of the recommended allowance (1,300 mg/day). On the other hand, weekly MVPA was higher than that recom- mended for adolescents. Signiicant differences in BMD and BMC were observed for girls aged 10-14 years. In addition, lumbar spine and femoral neck BMD was 58 and 31% higher in postpubertal girls, respectively, when compared to prepubertal adolescents.
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J. Pediatr. (Rio J.)  vol.91 número6

J. Pediatr. (Rio J.) vol.91 número6

Results: Overall, 73.9%, 54.2% and 42.8% of children had TV, computer, and videogames in the bedroom, respectively, and spent an average of 500.7 and 59.1 min/day of sedentary time and moderate-to-vigorous physical activity. Of the children, 45.3% were overweight/obese. Girls with a computer in the bedroom (45 min/day) performed less moderate-to-vigorous physical activity than those without it (51.4 min/day). Similar results were observed for body mass index in boys. Moderate-to-vigorous physical activity was higher and body mass index was lower in children that had no electronic equipment in the bedroom. Presence of a computer (ˇ = −4.798) and the combination TV + computer (ˇ = −3.233) were negatively associated with moderate- to-vigorous physical activity. Videogames and the combinations with two or three electronic devices were positively associated with body mass index. Sedentary time was not associated with electronic equipment.
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Does performing moderate-to-vigorous physical activity in 12 to 24 hours prior Bioelectrical Impedance Analysis affects the validity of body water compartments assessment?

Does performing moderate-to-vigorous physical activity in 12 to 24 hours prior Bioelectrical Impedance Analysis affects the validity of body water compartments assessment?

Possible explanations for the results obtained in the present study differ from the previous ones are time elapsed between the practice of MVPA and the measurements, i.e., it is expected that the participants of this study had the possibility of restoring all the water lost during the activity practiced the day before. This is possible if liquids and electrolytes are ingested in sufficient quantities and have been undergoing an extended period of recovery (eg 8-12 hours) since the last physical activity session until the time of the evaluation. Water and sodium retention are associated with the replacement of liquid electrolytes, which are crucial to the active lifestyle, reducing the likelihood of dehydration 89 .
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Lack of exercise of "moderate to vigorous" intensity in people with low levels of physical activity is a major discriminant for sociodemographic factors and morbidity.

Lack of exercise of "moderate to vigorous" intensity in people with low levels of physical activity is a major discriminant for sociodemographic factors and morbidity.

The results of the multinomial logistic regression are reported in terms of odds ratios (OR), confidence interval (95% CI) and statistical significance (p-value). The results are presented in bivariate form and adjusted for prior covariate selection obtained by stepwise analysis. The final model was selected with significant contributions (p,0.05) of age, sex, survey year, educational level, smoking habit, perceived fitness and 2 morbidities (cholesterol disorders and diabetes). The perceived health variable was discarded from the final analysis due to its association with perceived fitness (r50.41, p,0.05) and because it led to confusion in the results. In the final model, two other morbidities were included (high blood pressure and rheumatic pain) for their theoretical interest. The goodness-of-fit of the multivariate model was verified with Pearson’s Chi-Square test (p50.331), showing a correct fit of the model [ 56] with the 3 MVPA levels as dependent variable. The total percentage of correctly predicted cases was 62.5%. Data analyses were performed with the R statistical package [57] and the multinomial logistic regression module of the SPSS v.19 software package [58].
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Physical activity, sedentary time and bone tissue: effects of an 8-months interdisciplinary program with overweight/obese children

Physical activity, sedentary time and bone tissue: effects of an 8-months interdisciplinary program with overweight/obese children

Moderate to vigorous physical activity plays a recognized osteogenic effect on bone. Moreover, sed- entary time, and fat accumulation are unfavorable to bone health. Our study aimed (1) to examine changes in body composition, bone tissue, physical activity, and sedentary time; and (2) to explore whether changes in physical activity intensities and in sedentary time are associated with changes in bone outcomes after a school-based interdisciplinary intervention program. A total of 53 over- weight/obese students (10.6 ± 3.5 year-olds; 26 girls) participated in physical activity classes. Bone area, bone mass, and bone mineral density z-score, body composition (fat mass, fat lean mass), phys- ical activity, sedentary time and potential confounders (vitamin D and maturational status) were assessed at baseline, and 8 months later. General Linear Models were carried out and significance level was set at 5%. Changes in moderate to vigorous physical activity were positively correlated with changes in all bone mass indicators. We observed a significant overall effect of the intervention on bone mineral density z-score changes, however after adjustments for changes in sedentary time and moderate to vigorous physical activity, no effect was observed. Finally, variations in sedentary time and in moderate to vigorous physical activity play an important role in bone mass density in those participants of the interdisciplinary program.
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rev. educ. fis.  vol.19 número4

rev. educ. fis. vol.19 número4

The physical activity level was assessed through the short version of the International Physical Activity Questionnaire (IPAQ) (Guedes, Lopes & Guedes, 2005). IPAC is comprised of six questions about frequency of walking, enrollment in moderate physical activity and enrollment in vigorous physical activity. The students were asked to recall the amount of time spent in physical activity by estimating the intensity level, number of days, and daily average time spent exercising during the previous week. The resulting data was classified into quartiles: Q1 = extremely active, Q2= active, Q3 = moderately active, and Q4 = insufficiently active. The participants’ sedentary behavior patterns were determined using the Adolescent Sedentary Activity Questionnaire (QASA - Guimarães, da Silva, Legnani & Campos, 2012). QASA is comprised of 13 items divided into five categories of sedentary activities (electronics, educational, transportation, cultural and social). Participants informed the amount of time spent in each category of sedentary activity reporting the hours and/or minutes they spent throughout the week. The time spent in each sedentary activity category was calculated in minutes and computed the total time, which was the sum of all reported categories of sedentary activities. These calculations were separated for weekdays and weekends. The results were stratified into groups of sex and age. The total times spent with the weekly activities were organized in quartiles.
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Rev. paul. pediatr.  vol.33 número4

Rev. paul. pediatr. vol.33 número4

Logistic regression was used to assess the association between excessive screen time and sociodemographic varia- bles, level of physical activity and nutritional status. The model had excessive screen time as the dependent variable (≤2h/day=0 and >2h/day=1) and as independent variables: gender (female=1, male=2), age (14---15=3; 16---17=2, and 18---19 years =1), skin color (White =1 and non-White =2), socioeconomic class (class A/B=3, C=2, D/E=1), level of physical activity (physically active=1; physically inactive=2) and nutritional status (without excess body weight=1; with excess body weight=2). In the adjusted analysis, all the independent variables were included in the model and those with p-value <0.20 remained. The backward method was applied to select variables in the multivariate model. The Hosmer---Lemeshow test was used to assess the model goodness-of-fit.
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Association between religiosity, physical activity, and sedentary behavior in adolescents

Association between religiosity, physical activity, and sedentary behavior in adolescents

The instrument used in data collection was the questionnaire Global School- based Student Health Survey (GSHS), proposed by the World Health Organi- zation with the objective of assessing exposure to health risk behaviors among adolescents. The version in Portuguese was submitted to a validation process and to a pilot study and is available to readers upon request to the authors of this paper. It presented good consistency of measures and content and face validity. Reproducibility indicators (consistency of test-retest measurements) ranged from moderate to high in the majority of the items of the instrument, and the concor- dance coefficients varied from 0.52 to 1.0.
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Sedentary behaviour and physical activity in South Asian women: time to review current recommendations?

Sedentary behaviour and physical activity in South Asian women: time to review current recommendations?

Correlates of dysglycaemia in logistic regression analysis are shown in Table 4. Two models were derived. In model A, family history, food index, systolic blood pressure, BMI, waist circum- ference and the dichotomized variables (walking MET-minutes, moderate and vigorous physical activity MET-minutes, sitting time and TV viewing time), were used as independent variables (Table 4). In this preliminary model, moderate and vigorous physical activity MET-minutes, walking MET-minutes, TV viewing time, food index, and waist circumference were signifi- cantly associated with dysglycaemia after controlling for each other. In model B, systolic blood pressure, BMI and sitting time were excluded and an interaction term between waist circumfer- ence and TV viewing time was included (Table 4). Excepting family history of diabetes mellitus, all other variables including the interaction term were significantly associated with dysglycaemia. Females expending ,1435.3 MET-minutes/week on walking and ,2640.0 MET-minutes/week in moderate and vigorous physical activity were four times as likely to be dysglycaemic when compared to females with higher physical activity, giving an attributable fraction of 78% after adjusting for other variables. Women viewing TV for .85 minutes were six times as likely to be dysglycaemic when compared to those spending less time viewing TV; 85% of dysglycaemics could attribute their condition to viewing TV .85 minutes a day after adjusting for other variables. Women with a waist circumference .80 cm were 16 times as likely to be dysglycaemic when compared to females having waist
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Rev. Saúde Pública  vol.45 número2

Rev. Saúde Pública vol.45 número2

OBJECTIVE: To assess the reliability of the Lista de Atividades Físicas (Brazilian version of the Physical Activity Checklist Interview) in children. METHODS: The study is part of a cross-cultural adaptation of the Physical Activity Checklist Interview, conducted with 83 school children aged between seven and ten years, enrolled between the 2nd and 5th grades of primary education in the city of São Paulo, Southeastern Brazil, in 2008. The questionnaire was responded by children through individual interviews. It is comprised of a list of 21 moderate to vigorous physical activities performed on the previous day, it is divided into periods (before, during and after school) and it has a section for interview assessment. This questionnaire enables the quantifi cation of time spent in physical and sedentary activities and the total and weighed metabolic costs. Reliability was assessed by comparing two interviews conducted with a mean interval of three hours. For the interview assessment, data from the fi rst interview and those from an external evaluator were compared. Bland-Altman’s proposal, the intraclass correlation coeffi cient and Lin’s concordance correlation coeffi cient were used to assess reliability. RESULTS: The intraclass correlation coeffi cient lower limits for the outcomes analyzed varied from 0.84 to 0.96. Precision and agreement varied between 0.83 and 0.97 and between 0.99 and 1, respectively. The line estimated from the pairs of values obtained in both interviews indicates high data precision. The interview item showing the poorest result was the ability to estimate time (fair in 27.7% of interviews). Interview assessment items showed intraclass correlation coeffi cients between 0.60 and 0.70, except for level of cooperation (0.46). CONCLUSIONS: The Brazilian version of the Physical Activity Checklist Interview shows high reliability to assess physical and sedentary activity on the previous day in children.
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Rev. Saúde Pública  vol.46 número2

Rev. Saúde Pública vol.46 número2

METHODS: School-based cross-sectional study carried out by means of the observation of 218 Physical Education classes, including a total of 272 students (each one of the students was evaluated three times). The study was carried out in the city of Pelotas (Southern Brazil), between August and December 2009. In order to evaluate the intensity of the efforts, accelerometers were used and the following cut-off points were adopted (in counts per minute): sedentary activities (0-100), light activities (101-2,000), moderate (2,001- 4,999), vigorous (5,000-7,999), and very vigorous activities (>8000). RESULTS: The mean duration of the classes was 35.6 minutes (SD 6.0). The mean proportion of time spent in moderate to vigorous physical activity was 32.7% (SD 25.2). Boys (44.1%) were involved signifi cantly more in moderate to vigorous physical activity as compared to girls (21.0%; p<0.01). Students who practice physical activities outside the classes participated more in moderate to vigorous physical activity in the Physical Education classes. CONCLUSIONS: Besides the fact that Physical Education classes have a short duration, students practice moderate to vigorous physical activity during one third of the class, with a poor signifi cant contribution to students’ level of physical activity.
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Moderate-vigorous physical activity across body mass index in females: moderating effect of endocannabinoids and temperament.

Moderate-vigorous physical activity across body mass index in females: moderating effect of endocannabinoids and temperament.

Finally, Novelty seeking and plasma AEA concentrations were both found to be positively linked to MVPA. Van Laere et al [31] evaluated CB1 receptor availability in temperament, finding greater global cerebral CB1 receptor availability to be inversely related to Novelty seeking. Novelty seeking may interact with the eCB system via the engagement in MVPA. Furthermore, the activation of this system with exercise appears to result in exercise- induced analgesia and may be responsible for the reported runner’s high, a transient and intense feeling of happiness, elation, and energy [20]. Our results support the concept that individuals who are high in impulsive traits may engage in PA to achieve a gratifying state, following a positive reinforcement conditioning, whereas more passive and less energetic individuals, such as those who present elevated Harm avoidance, present more sedentary behavior. Reduction in the BMI might be a consequent effect, but also may act as a maintaining factor of this vicious circle. Further research is needed to understand the mechanisms of these associations. For instance OEA is not a CB1 agonist and it is best known for acting as a fat sensor in the intestine, but in a recent report it has been suggested that OEA is also involved in the reward system by stimulating central dopamine activity [69] and may participate in the control of reward-related behaviors through a PPARa receptor-independent mechanism [70].
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Sedentary behavior as a predictor of functional disability in older adults

Sedentary behavior as a predictor of functional disability in older adults

Mean and standard deviation were used to represent descriptive information on the different study variables. Kolmogorov-Smirnov tests were used to verify normal distribution of data before deriving association and comparison analyses. Independent T-tests were used to compare sociodemographic, physical activity and SB data according to gender (male-female). Pearson production-moment correlation coefficients were used to examine associations between estimates of SB from weekdays and weekend days. Receiver Operating Char- acteristic (ROC) curves were applied to identify the SB cut-points with highest discriminatory power for pres- ence of functional disability. This technique is frequent- ly used to verify the diagnostic performance of clinical exams and tests. It consists in the identification of the total area under the ROC curve overlapping independ- ent and dependent variables. The higher the area under the ROC curve, the better the discriminatory power of the independent variable for the dependent variable. To determine if individuals with time spent in SB higher than the cut-point value had higher likelihood of func- tional disability, a Poisson regression analysis was used with the SB cut-point value set as the independent
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Associations between physical activity, sedentary behavior, and health risk behaviors among adolescents from a city in Southern Brazil

Associations between physical activity, sedentary behavior, and health risk behaviors among adolescents from a city in Southern Brazil

Based on the interaction between PA and SB, in- creasing levels of MVPA or lowering SB were associat- ed with higher rates of mild and excessive alcohol use by brazilian adolescents. These results highlight the im- portance of considering SB when using PA to predict mild and excessive use of alcohol among adolescents. In fact, even adolescents in the group with low MVPA and low SB were ~3 times more likely to report exces- sive alcohol use than those in the low MVPA and high SB. Increasing PA participation and reducing SB time are common health recommendations for adolescents. However, the association of these behaviors with alco- hol use suggests the implementation of compensatory strategies for possible increases in SB not to overshad- ow the benefits of a more active lifestyle.
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Associations between environmemtal features and physical activity in youth.

Associations between environmemtal features and physical activity in youth.

asking them to identify their child’s usual play areas. The most common answers were related to the yard of their home, but more than one-third of parents said their child often played outside or in open play spaces, determinants that were also confirmed by Timperio et al. (Timperio, Crawford, Telford, & Salmon, 2004). On the other hand, girls whose parents reported no access to play areas were less likely to walk or cycle in their neighborhood (Timperio et al., 2004). Indeed, safety is an important concern for parents and children (Mullan, 2003). This concern contributes to parental restrictions associated with the independent mobility of their child (Hume et al., 2009; Veitch et al., 2006) and active transport in their own neighborhood (A. Carver, A. Timperio, & D. Crawford, 2008b; Gielen et al., 2004). Carver et al. (2008a) reported that parents’ perception of safety was positively associated with adolescent boys’ moderate to vigorous physical activity after school. This could be due to adolescents’ independence. Veitch et al. (Veitch et al., 2006) reported that parents of older children (9-10 years old) were more likely to allow their child to walk or cycle to friends’ houses or to a local place than were parents of young children (6-8 years old). They indicated that having a dog could also provide their child more protection for playing in the street (Mullan, 2003). In some studies, though, no association was found between having a dog and child’s protection. (Adkins et al., 2004; J. Mota et al., 2005).
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Rev. Saúde Pública  vol.47 número3

Rev. Saúde Pública vol.47 número3

METHODS: This study complements the cross-cultural adaptation of the Physical Activity Checklist Interview, conducted with 118 school children aged between seven and ten years old, enrolled from the second to the fi fth grades of primary education in the city of São Paulo, SP, Southeastern Brazil, in 2009. The questionnaire enables the quantifi cation of time spent in moderate and vigorous physical activities and sedentary activities and the total and weighted metabolic costs. The accelerometer was adopted as a criterion measure of physical activity. The variables total physical activity (counts/min) and time spent in moderate to vigorous physical activity were quantifi ed. The concurrent validity was assessed by Pearson’s correlation coeffi cient while the operational equivalence was assessed by data concerning the duration and evaluation of the interview. RESULTS: The values for the correlation coeffi cient between the results from the questionnaire and the accelerometer ranged from 0.34 to 0.40. It was found that LAF overestimates time spent doing moderate and vigorous physical activity when compared to the accelerometer. The average duration of the interviews was 24 minutes (minimum = 13 min, maximum = 41 min, sd = 5 min). The interview item showing the poorest result was the children’s ability to estimate time (poor or fair in 24.8% of interviews).
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Rev. bras. epidemiol.  vol.11 número3

Rev. bras. epidemiol. vol.11 número3

Introduction: Practicing regular, moderate to vigorous physical activities has an inverse relation to morbidity-mortality caused by cardiovascular diseases and obesity. It is essential to identify the determinants of this practice in order to propose strategies for populations to adopt a physically ac- tive lifestyle. Objective: To determine the factors associated with practicing physical activity and sedentary lifestyle in the adult population of Goiania. Methods: Multi- center, cross-sectional study, carried out in Goiania with a probabilistic sample of the adult population with landline phones. 2,002 interviews were conducted through phone calls, setting a success rate of 73.1%. The database was built, and statistical analyses were carried out with the support of STATA software, version 8.0. Results: A se- dentary lifestyle was more prevalent among women (55.5%) than among men (42.0%). The prevalence of hypertension was lower in individuals practicing physical activity (p=0.0002). Regarding leisure-time physical activity, women were more inactive (79.3%) than men (66.9%). There was an inverse relationship between a sedentary lifestyle and the educational background for both genders. Conclusion: Due to this snapshot, showing a high frequency of sedentary lifestyle in the population, we suggest the implementation of primary prevention strategies to improve the risk profile for non- communicable chronic diseases.
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