Global, regional, and national trends and patterns in physical activity research since 1950: a systematic review.

BACKGROUND: National, regional and global scientific production and research capacity for physical activity - PA may contribute to improving public health PA policies and programs. There is an uneven distribution of research productivity by region and country income group, where countries with the highest burden of non-communicable diseases attributable to physical inactivity having low research productivity. A first step towards improving global research capacity is to objectively quantify patterns, trends, and gaps in PA research. This study describes national, regional and global trends and patterns of PA research from 1950 to 2019. METHODS: A systematic review using searches in PubMed, SCOPUS and ISI Web of Knowledge databases was conducted in August 2017 and updated between January and May 2020. The review was registered at the PROSPERO database number CRD42017070153. PA publications per 100,000 inhabitants per country was the main variable of interest. Descriptive and time-trend analyses were conducted in STATA version 16.0. RESULTS: The search retrieved 555,468 articles of which 75,756 were duplicates, leaving 479,712 eligible articles. After reviewing inclusion and exclusion criteria, 23,860 were eligible for data extraction. Eighty-one percent of countries (n = 176) had at least one PA publication. The overall worldwide publication rate in the PA field was 0.46 articles per 100,000 inhabitants. Europe had the highest rate (1.44 articles per 100,000 inhabitants) and South East Asia had the lowest (0.04 articles per 100,000 inhabitants). A more than a 50-fold difference in publications per 100,000 inhabitants was identified between high and low-income countries. The least productive and poorest regions have rates resembling previous decades of the most productive and the richest. CONCLUSION: This study showed an increasing number of publications over the last 60 years with a growing number of disciplines and research methods over time. However, striking inequities were revealed and the knowledge gap across geographic regions and by country income groups was substantial over time. The need for regular global surveillance of PA research, particularly in countries with the largest data gaps is clear. A focus on the public health impact and global equity of research will be an important contribution to making the world more active.

Influence of parental physical activity on offspring's nutritional status: an intergenerational study in the 1993 Pelotas birth cohort.

OBJECTIVE: To investigate the influence of parental physical activity on offspring's nutritional status in the 1993 Pelotas (Brazil) birth cohort. DESIGN: Birth cohort study. SETTING: The main outcomes were overweight and obesity status of children. The main exposure was parental physical activity over time, measured during the 11, 15 and 18 years of age follow-ups. The exposure was operationalised as cumulative, and the most recent measure before the birth of child. We adjusted Poisson regression models with robust variance to evaluate crude and adjusted associations between parental physical activity and offspring's nutritional status. All analyses were stratified according to the sex of the parent. PARTICIPANTS: A total of 874 members from the 1993 Pelotas (Brazil) birth cohort followed-up at 22 years of age with their first-born child were analysed. RESULTS: Children were, on average, 3·1 years old. Crude analyses showed that the mother's cumulative physical activity measure had an indirect association with the prevalence of children's obesity. The most recent maternal physical activity measure before the birth of the child was associated with 41 % lower prevalence of obesity in children, even after adjustment for confounders. CONCLUSIONS: The most recent maternal physical activity measure was indirectly associated with the prevalence of obesity in children. No associations were found for fathers, reinforcing the hypothesis of a biological effect of maternal physical activity on offspring's nutritional status.

Maternal and child-health outcomes in pregnancies following Assisted Reproductive Technology (ART): a prospective cohort study.

BACKGROUND: Studies comparing the outcome of spontaneous versus assisted reproductive technologies (ART) pregnancies report heterogeneous results. Despite the success of ART to overcome infertility, concern is growing regarding both its safety and its effect on maternal and child health. The objective of this study was to compare maternal and child-health outcomes after ART relative to natural conception. METHODS: A population-based birth cohort study was carried out among pregnant women expected to deliver in 2015 in Pelotas, southern Brazil. Maternal outcomes included pregnancy complications and gestational weight gain. Gestational age, weight, intrauterine growth restriction, length and head circumference, and 1-min and 5-min Apgar, as well as health problems at birth and breastfeeding were defined as offspring outcomes. Statistical analyses were performed using linear and logistic regression. G-formula was used to perform mediation analysis. RESULTS: The study included 4252 babies born by spontaneously pregnancies and 23 babies born after ART. Adjusted analyses showed that children conceived from ART presented lower means of gestational age (p = 0.001), birth weight (p = 0.002), length (p < 0.001), and head circumference at birth (p = 0.02). However, more than 90% of the effect of ART over these outcomes was mediated by multiple pregnancy. CONCLUSION: Our findings suggest that the possible negative effect on the child-health outcomes is due mainly to the higher incidence of multiple pregnancies and not because of ART. The reasons for the increase in adverse pregnancy outcomes associated with ART singleton pregnancies are still uncertain and warrants further research. Further large-population studies are needed to confirm these results.

A randomized controlled trial of exercise during pregnancy on maternal and neonatal outcomes: results from the PAMELA study.

BACKGROUND: Women are encouraged to be physically active during pregnancy. Despite available evidence supporting antenatal physical activity to bring health benefits for both the mother and child, the most effective way to prevent some maternal and fetal outcomes is still unclear. The purpose of this study was to evaluate the efficacy of an exercise intervention to prevent negative maternal and newborn health outcomes. METHODS: A randomized controlled trial (RCT) nested into the 2015 Pelotas (Brazil) Birth Cohort Study was carried-out with 639 healthy pregnant women, 213 in the intervention group (IG) and 426 in the control (CG) group. An exercise-based intervention was conducted three times/week for 16 weeks from 16-20 to 32-36 weeks' gestation. The main outcomes were preterm birth and pre-eclampsia. Gestational age was calculated based on several parameters, including routine ultrassounds and/or last menstrual period and categorized as < 37 weeks and ≥ 37 weeks for evaluation of preterm birth. Pre-eclampsia was self-reported. Secondary outcomes were gestational weight gain, gestational diabetes, birth weight, infant length, and head circumference. Analyses were performed by intention-to-treat (ITT) and per protocol (70% of the 48 planned exercise sessions). Odds ratio were derived using unconditional logistic regression. RESULTS: The IG and CG did not differ at baseline regarding their mean age (27.2 years ± 5.3 vs. 27.1 years ± 5.7) and mean pre-pregnancy body mass index (25.1 ± 3.9 vs. 25.2 ± 4.1 kg/m2). The mean adherence to the exercise intervention was 27 ± 17.2 sessions (out of a potential 48) with 40.4% attending > = 70% of the recommended exercise sessions. A total of 594 participants (IG:198; CG: 396) were included in the ITT and 479 (IG: 83; CG: 396) were included in the per protocol analyses. There were no significant differences in the incidence of preterm birth and pre-eclampsia between groups in the ITT and per protocol analysis. There were also no differences between the two groups in mean gestational weight gain, gestational diabetes, birth weight, infant length, and head circumference. CONCLUSIONS: While the RCT did not support the benefits of exercise performed during pregnancy on preeclampsia and preterm birth, the exercise program also did not present adverse impacts on newborn health. Our findings may contribute to promote intervention strategies that motivate health providers to encourage pregnant women to be more physically active. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT02148965 , registered on 22 May 2014.

Inequalities in Leisure-Time Physical Activity and Television Viewing According to Age Among a Brazilian Adult Population.

BACKGROUND: The present study aims to estimate leisure-time physical activity and television (TV) viewing curves according to age stratified by sex, area of residence, and socioeconomic position. METHODS: Using data from the Brazilian National Health Survey, we estimated the prevalence of leisure-time physical activity and TV viewing according to continuous age. The estimates were calculated using fractional polynomials and stratified by sex, wealth, skin color, and area of residence. RESULTS: The sample included 87,376 adults (aged 18 y or over). In general, leisure-time physical activity decreased according to age while TV viewing increased. Regarding behavior of curves according to stratifiers, for leisure-time physical activity the disadvantaged groups maintained a pattern of low physical activity across all age groups or presented the decrease earlier when compared to groups in social advantage. On the other hand, for TV viewing, women presented an increase in prevalence before men, and individuals living in the urban area and the wealthiest group were those with a higher increase according to age. CONCLUSIONS: Our findings may help researchers and policymakers further explore inequalities in physical activity across life in different settings, as well as develop sensitive cultural actions to support more vulnerable people to adopt public health recommendations.

Severe Acute Respiratory Syndrome (SARS) in the Context of the COVID-19 Pandemic Among Indigenous Peoples of Brazil: Epidemiology and Risk Factors Associated with Death.

INTRODUCTION: Severe Acute Respiratory Syndrome (SARS) represents a serious public health problem for the indigenous peoples of Brazil, since acute respiratory infections are the main causes of morbidity and mortality in this population. OBJECTIVE: To assess cases of SARS in Brazilian indigenous peoples in the context of the COVID-19 pandemic, as well as sociodemographic and health factors associated with deaths from SARS in this population. METHODS: Ecological study carried out based on secondary data from the Brazilian Database for Epidemiological Surveillance of Influenza referring to the Brazilian indigenous population with SARS in 2020. The variables included sociodemographic factors and health conditions. Statistical analyses were carried out considering absolute (n) and relative (%) frequencies and logistic regression with odds ratios (OR), with death as the outcome of interest. RESULTS: A total of 3062 cases were reported in the analyzed period. Of these, there was a predominance of men (54.6%), adults (41.4%), with comorbidities (52.3%), with low levels of schooling (67.4%) and residents of rural areas (55.8%). Cases and deaths were concentrated in the states of Amazonas and Mato Grosso do Sul, states in the North and Midwest of Brazil. A greater chance of death was observed in elderly indigenous people (OR = 6.29; 95%CI 4.71-8.39), with low levels of schooling (OR = 1.72; 95%CI 1.22-2.28), residents of rural areas (OR = 1.35; 95%CI 1.12-1.62), and with comorbidities (OR = 1.87; 95%CI 1.42-2.46), especially obesity (OR = 2.56; 95%CI 1.07-6.11). CONCLUSION: The study was able to trace the clinical-epidemiological profile, as well as identify the groups of indigenous people most vulnerable to SARS as a result of COVID-19 and evolution to death in Brazil. The findings show the high impact on the morbidity and mortality of the Brazilian indigenous population exposed to SARS and are relevant for epidemiological health surveillance, since they can guide preventive public policy actions and quality of life measures for this ethnic group in Brazil.

Efficacy of Regular Exercise During Pregnancy on the Prevention of Postpartum Depression: The PAMELA Randomized Clinical Trial.

Importance: Interventions to reduce postpartum depression have mainly focused on enhancing screening to increase treatment rates among women. Preventive approaches are timely from a population health perspective, particularly in low- and middle-income countries where access to mental health services is limited. Objective: To assess the efficacy of regular exercise during pregnancy on the prevention of postpartum depression. Design, Setting, and Participants: This randomized clinical trial examines a prespecified secondary outcome of the Physical Activity for Mothers Enrolled in Longitudinal Analysis (PAMELA) Study, a parallel-group, randomized clinical trial. This trial was nested in the 2015 Pelotas (Brazil) Birth Cohort Study. Between August 27, 2014, and March 14, 2016, pregnant women between 16 and 20 weeks of gestation with no contraindications to exercise were randomized 1:2 to the intervention group or control group via computer-generated randomization using a block size of 9. Data were analyzed from March 7 to May 2, 2018. Interventions: Participants assigned to the intervention were engaged in a 16-week supervised exercise program including aerobic and resistance training delivered in 60-minute sessions 3 times per week. Main Outcomes and Measures: Postpartum depressive symptoms were assessed with the Edinburgh Postnatal Depression Scale 3 months after birth. A score of 12 or greater was defined as screening positive for postpartum depression. Primary analysis was performed on a complete case basis (90% of participants who had the primary end point ascertained). Results: A total of 639 participants (mean [SD] age, 27.1 [5.1] years; mean gestational age, 16.5 [1.5] weeks) were randomly assigned to the intervention group (n = 213) or control group (n = 426). Compliance with the protocol, defined as having engaged in at least 70% of exercise sessions, was low (40.4%). There was no significant difference in mean (SD) scores for postpartum depression between the intervention group (4.8 [3.7]) and the control group (5.4 [4.1]) (mean difference, -0.6; 95% CI, -1.3 to 0.1). There was also no significant difference in rates of postpartum depression between the intervention group (12 of 192 [6.3%]) and the control group (36 of 387 [9.3%]) (odds ratio, 0.65; 95% CI, 0.33-1.28). Instrumental variable analysis indicated that noncompliance may have attenuated the effect estimates obtained in the primary analysis. Conclusions and Relevance: Moderate-intensity exercise during pregnancy did not lead to significant reductions in postpartum depression. However, noncompliance to the intervention protocol was substantial and may have led to underestimations of the possible benefits of exercise. The point estimates for this study are in the same direction as the previous randomized clinical trial on this topic. Future studies on how to promote regular exercise during pregnancy to improve compliance, particularly targeting young and less educated women, are warranted before further trials are undertaken. Trial Registration: ClinicalTrials.gov Identifier: NCT02148965.

How many days are needed to estimate wrist-worn accelerometry-assessed physical activity during the second trimester in pregnancy?

BACKGROUND: Objective methods to measure physical activity (PA) can lead to better cross-cultural comparisons, monitoring temporal PA trends, and measuring the effect of interventions. However, when applying this technology in field-work, the accelerometer data processing is prone to methodological issues. One of the most challenging issues relates to standardizing total wear time to provide reliable data across participants. It is generally accepted that at least 4 complete days of accelerometer wear represent a week for adults. It is not known if this same assumption holds true for pregnant women. AIM: We assessed the optimal number of days needed to obtain reliable estimates of overall PA and moderate-to-vigorous physical activity (MVPA) during the 2nd trimester in pregnancy using a raw triaxial wrist-worn accelerometer. METHODS: Cross-sectional analyses were carried out in the antenatal wave of the 2015 Pelotas (Brazil) Birth Cohort Study. Participants wore the wrist ActiGraph wGT3X-BT accelerometer for seven consecutive days. The daily average acceleration, which indicated overall PA, was measured as milli-g (mg), and time spent in MVPA (minutes/day) was analyzed in 5-minute bouts. ANOVA and Kruskal-Wallis tests were used to compare variability across days of the week. Bland-Altman plots and the Spearman-Brown Prophecy Formula were applied to determine the reliability coefficient associated with one to seven days of measurement. RESULTS: Among 2,082 pregnant women who wore the accelerometer for seven complete days, overall and MVPA were lower on Sundays compared to other days of the week. Reliability of > = 0.80 to evaluate overall PA was reached with at least three monitoring days, whereas seven days were needed to estimate reliable measures of MVPA. CONCLUSIONS: Our findings indicate that obtaining one week of accelerometry in adults is appropriate for pregnant women, particularly to obtain differences on weekend days and reliably estimate overall PA and MVPA.

Clustering of Physical Inactivity in Leisure, Work, Commuting, and Household Domains: Data From 47,477 Industrial Workers in Brazil.

BACKGROUND: Physical inactivity in each domain (leisure, work, commuting, and household) is not completely independent. This study aimed to describe the clustering of physical inactivity in different domains and its association with sociodemographic factors among Brazilian industrial workers. METHODS: This was a cross-sectional, population-based study using data from 23 Brazilian states and the Federal District collected via questionnaires between 2006 and 2008. Physical inactivity in each domain was defined as nonparticipation in specific physical activities. Clustering of physical inactivity was identified using the ratio of the observed (O) and expected (E) percentages of each combination. Multinomial logistic regression was used to identify sociodemographic factors with the outcome. RESULTS: Among the 44,477 interviewees, most combinations exceeded expectations, particularly the clustering of physical inactivity in all domains among men (O/E = 1.37; 95% CI: 1.30; 1.44) and women (O/E = 1.47; 95% CI: 1.36; 1.60). Physical inactivity in 2 or more domains was observed more frequently in women, older age groups, individuals living without a partner, and those with higher education and income levels. CONCLUSIONS: Physical inactivity tends to be observed in clusters regardless of gender. Women and workers with higher income levels were the main factors associated with to be physically inactive in 2 or more domains.

Physical activity during pregnancy and maternal-child health (PAMELA): study protocol for a randomized controlled trial.

BACKGROUND: Preterm birth is associated with most cases of neonatal deaths and negative health outcomes, and hypertensive disorders. Hypertension is influenced by maternal behavior, such as physical activity. Physical activity is associated with better outcomes for mother and fetus, besides healthier weight gains during pregnancy. Few women are physically active during pregnancy and few clinical trials have been carried out with pregnant women. The aim of this paper is to describe the protocol of a controlled trial evaluating whether regular exercise during pregnancy may result in improved maternal-child health and neonatal outcomes. METHODS/DESIGN: The PAMELA (Physical Activity for Mothers Enrolled in Longitudinal Analysis) trial is a randomized controlled trial nested in a birth cohort study. Eligible women belonging to the birth cohort will be invited (between the 16th and 20th week of gestation) to enroll in the trial. Baseline data (blood and urine samples, anthropometry and pulmonary function) will be collected at enrollment. The same assessments will be repeated eight and 16 weeks after baseline. After randomization, women will be allocated into either one of these groups: control, 426 women who will be advised to keep their usual daily activities; and intervention, 213 women who will engage in an exercise program, three sessions a week. At least 70 % attendance over 16 weeks will be required to be considered compliant to the intervention. Exercise protocol will include aerobics, strength and flexibility training. Maternal and child outcomes will be measured at the 36th week of gestation, at birth and at three, 12, 24 and 48 months postpartum. An intention-to-treat analysis will be performed. DISCUSSION: Few women are active during pregnancy and a vast majority decrease their activities or even quit exercising. We present a population-based regular exercise intervention focused on the prevention of hypertension, pre-eclampsia and preterm birth. Data on the underlying cohort will allow future analysis using different outcomes with low probability of recall bias or misclassification of exposure status. Results will potentially influence prenatal care counseling in regards to physical activity. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT02148965 , registered on 22 May 2014.

Commuting to school and to work among high school students in Santa Catarina state, Brazil: a comparative analysis between 2001 and 2011.

BACKGROUND: Commuting reflects an important opportunity for youth to engage in physical activity. This study aimed to compare modes of commuting to school and to work and to identify sociodemographic factors associated with various modes of transportation. METHODS: Epidemiologic study with a repeated cross-sectional design. Participants included high school students (15-19 years of age) from Santa Catarina state, Brazil, in 2001 (n = 5028) and 2011 (n = 6529). A questionnaire containing information on the type of transport used to commute to school and to work was administered. RESULTS: Walking/bicycling and the use of the bus to commute to school and to work remained stable after a decade; however, the use of car/motorcycle to school (6.4% versus 12.6%) and to work (10.2% versus 19.7%) increased significantly. In both cases, females more frequently used buses, whereas males commuted to work by car/bus. Students from rural areas more commonly commuted to school by car/motorcycle, whereas those from urban areas traveled to work more by bus. There was a greater use of cars/motorcycles by young people from higher-income families. CONCLUSIONS: The use of cars/motorcycles to commute to school/work has almost doubled in the last decade. Sex, residential area and income were associated with passive commuting.