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Obesity and physical inactivity are considered possible U.S. national security threats because of their impact on military recruitment. The objectives of this study were to estimate the prevalence of (1) BMI eligibility for military entrance, (2) adequate physical activity participation among the BMI-eligible population, and (3) combined BMI eligibility and adequate physical activity.This cross-sectional study of nonpregnant, military-aged civilians (aged 17-42 years) used objectively measured weight and height data and self-reported aerobic physical activity data from the 2015-2020 National Health and Nutrition Examination Survey. BMI eligibility was defined as 19.0-27.5 kg/mOf military-aged participants (unweighted n=5,964), 47.3% were eligible by BMI. Among BMI-eligible participants, 72.5% reported adequate physical activity. Taken together, 34.3% were both eligible and active. The prevalence of eligible and active status was higher among males, persons who were younger and non-Hispanic White, college graduates, and those with higher family income than among their counterparts.Among the military-aged U.S. population, slightly under half were eligible to enter the military on the basis of their BMI, and only 1 in 3 met BMI eligibility and were adequately physically active. Equitable promotion of healthy weight achievement and physical activity participation may improve military preparedness.

Background: Assessing awareness and knowledge of the Physical Activity Guidelines for Americans, 2nd edition (Guidelines), released in 2018, is important for monitoring factors that contribute to increasing physical activity. Methods: We estimated prevalence of awareness and knowledge of the adult aerobic guideline (≥150 min/wk of moderate-intensity equivalent aerobic physical activity preferably spread out over a week) among adults (n = 3471) and of the youth aerobic guideline (≥60 min/d of mostly moderate- to vigorous-intensity aerobic physical activity) among a subset of parents (n = 744) from a nationwide sample of US adults in the 2019 FallStyles survey. We estimated odds ratios using logistic regression, adjusting for demographic and other characteristics. Results: Approximately 1 in 10 US adults and parents reported being aware of the Guidelines. Only 3% of adults knew the correct adult aerobic guideline. The most common responses were “don’t know/not sure” (44%) and “30 minutes a day, 5 or more days a week” (28%). Among parents, 15% knew the youth aerobic guideline. Awareness and knowledge tended to be lower with lower education and income. Conclusions: Limited awareness and knowledge of the Guidelines suggest communication about the Guidelines could be strengthened, especially among adults with low income or education.

Telehealth is the use of electronic information and telecommunication technologies to provide care when the patient and the provider are not in the same room at the same time. Telehealth accounted for less than 1% of all Medicare Fee-for-Service outpatient visits in the United States in 2019 but grew to account for 46% of all visits in April 2020. Changes in reimbursement and licensure policies during the COVID-19 pandemic appeared to greatly facilitate this increased use. Telehealth will continue to account for a substantial portion of care provided in the United States and globally. A better understanding of telehealth approaches and their evidence base by public health practitioners may help improve their ability to collaborate with health care organizations to improve population health. The article summarizes the Centers for Disease Control and Prevention's (CDC's) approach to understanding the evidence base for telehealth in public health practice, possible applications for telehealth in public health practice, and CDC's use of telehealth to improve population health.

Long-term symptoms often associated with COVID-19 (post-COVID conditions or long COVID) are an emerging public health concern that is not well understood. Prevalence of post-COVID conditions has been reported among persons who have had COVID-19 (range = 5%-80%), with differences possibly related to different study populations, case definitions, and data sources (1). Few studies of post-COVID conditions have comparisons with the general population of adults with negative test results for SARS-CoV-2, the virus that causes COVID-19, limiting ability to assess background symptom prevalence (1). CDC used a nonprobability-based Internet panel established by Porter Novelli Public Services* to administer a survey to a nationwide sample of U.S. adults aged ≥18 years to compare the prevalence of long-term symptoms (those lasting >4 weeks since onset) among persons who self-reported ever receiving a positive SARS-CoV-2 test result with the prevalence of similar symptoms among persons who reported always receiving a negative test result. The weighted prevalence of ever testing positive for SARS-CoV-2 was 22.2% (95% confidence interval [CI] = 20.6%-23.8%). Approximately two thirds of respondents who had received a positive test result experienced long-term symptoms often associated with SARS-CoV-2 infection. Compared with respondents who received a negative test result, those who received a positive test result reported a significantly higher prevalence of any long-term symptom (65.9% versus 42.9%), fatigue (22.5% versus 12.0%), change in sense of smell or taste (17.3% versus 1.7%), shortness of breath (15.5% versus 5.2%), cough (14.5% versus 4.9%), headache (13.8% versus 9.9%), and persistence (>4 weeks) of at least one initially occurring symptom (76.2% versus 69.6%). Compared with respondents who received a negative test result, a larger proportion of those who received a positive test result reported believing that receiving a COVID-19 vaccine made their long-term symptoms better (28.7% versus 15.7%). Efforts to address post-COVID conditions should include helping health care professionals recognize the most common post-COVID conditions and optimize care for patients with persisting symptoms, including messaging on potential benefits of COVID-19 vaccination.

Background: Surveillance is a core function of public health, and approaches to national surveillance of physical activity and sedentary behavior have evolved over the past 2 decades. The purpose of this paper is to provide an overview of surveillance of physical activity and sedentary behavior in the United States over the past 2 decades, along with related challenges and emerging opportunities. Methods: The authors reviewed key national surveillance systems for the assessment of physical activity and sedentary behavior among youth and adults in the United States between 2000 and 2019. Results: Over the past 20 years, 8 surveillance systems have assessed physical activity, and 5 of those have assessed sedentary behavior. Three of the 8 originated in nonpublic health agencies. Most systems have assessed physical activity and sedentary behavior via surveys. However, survey questions varied over time within and also across systems, resulting in a wide array of available data. Conclusion: The evolving nature of physical activity surveillance in the United States has resulted in both broad challenges (eg, balancing content with survey space; providing data at the national, state, and local level; adapting traditional physical activity measures and survey designs; and addressing variation across surveillance systems) and related opportunities.

Background: Adults should perform ≥150 minutes per week of moderate-intensity equivalent physical activity for substantial health benefits and >300 minutes per week for additional benefits. The authors analyzed 21 years of National Health Interview Survey data to better understand trends in aerobic physical activity participation among US adults. Methods: The authors estimated the annual prevalence (1998–2018) of self-reported leisure-time physical inactivity, insufficient activity, meeting only the minimal aerobic guideline, and meeting the high aerobic guideline overall and by selected characteristics. Prevalence differences between 1998 and 2018 were compared across subgroups and periods of significant change were identified using JoinPoint regression. Results: The prevalence of inactivity decreased from 40.5% (1998) to 25.6% (2018) while the prevalence of meeting the high aerobic guideline increased from 26.0% to 37.4%. Increases in meeting the high guideline were similar across age groups, racial/ethnic groups, levels of education, and Census regions. Increases in insufficient activity and meeting the minimal guideline were statistically significant but of relatively small magnitude. Conclusions: The prevalence of inactivity decreased and meeting the high aerobic guideline increased overall and for all subgroups from 1998 to 2018. Physical activity promotion strategies may aim to continue these trends while also narrowing persistent disparities in participation across subgroups.

Background: Although disparities in leisure-time physical activity (LTPA) participation by race/ethnicity and income are known, the combined association of these characteristics with LTPA participation is less understood. This study aims to describe trends and determine whether racial/ethnic differences in adult physical activity by income level have changed over the past 2 decades. Methods: The authors estimated LTPA participation (outcomes: any aerobic activity, meeting the aerobic activity guideline, meeting the muscle-strengthening guideline, and meeting the combined aerobic and muscle-strengthening guidelines) among adults ≥18 years by race/ethnicity across income levels using 1998–2018 National Health Interview Survey data in 3-year aggregates. They also tested for trends, prevalence differences, and difference in differences using logistic regression. Results: LTPA participation increased from 1998–2000 to 2016–2018 for all outcomes for non-Hispanic white, non-Hispanic black, and Hispanic adults at all income levels. Disparities narrowed for some groups but persisted between white and racial/ethnic minority groups across income levels for engaging in any aerobic activity and meeting the aerobic guideline (0.2–8.8 percentage point difference in differences). Disparities in meeting the muscle-strengthening and combined guidelines were less common. Conclusions: Opportunities exist to ensure that adults, particularly members of lower income racial/ethnic minority groups, have support to help them participate in LTPA.

Background Physical activity (PA) provides numerous health benefits relevant to the COVID-19 pandemic. However, concerns exist that PA levels may have decreased during the pandemic thus exacerbating health disparities. This study aims to determine changes in and locations for PA and reasons for decreased PA during the pandemic. Methods Reported percentage of changes in and locations for PA and reasons for decreased PA were examined in 3829 US adults who completed the 2020 SummerStyles survey. Results Overall, 30% reported less PA, and 50% reported no change or no activity during the pandemic; percentages varied across subgroups. Adults who were non-Hispanic Black (Black) or Hispanic (vs. non-Hispanic White, (White)) reported less PA. Fewer Black adults (vs. White) reported doing most PA in their neighborhood. Concern about exposure to the virus (39%) was the most common reason adults were less active. Conclusions In June 2020, nearly one-third of US adults reported decreased PA; 20% reported increased PA. Decreased activity was higher among Black and Hispanic compared to White adults; these two groups have experienced disproportionate COVID-19 impacts. Continued efforts are needed to ensure everyone has access to supports that allow them to participate in PA while still following guidance to prevent COVID-19 transmission.

ObjectiveTo examine the association of leisure-time physical activity with mortality from influenza and pneumonia.MethodsA nationally representative sample of US adults (aged ≥18 years) who participated in the National Health Interview Survey from 1998 to 2018 were followed for mortality through 2019. Participants were classified as meeting both physical activity guidelines if they reported ≥150 min/week of moderate-intensity equivalent aerobic physical activity and ≥2 episodes/week of muscle-strengthening activity. Participants were also classified into five volume-based categories of self-reported aerobic and muscle-strengthening activity. Influenza and pneumonia mortality was defined as having an underlying cause of death with an International Classification of Diseases, 10th Revision code of J09–J18 recorded in the National Death Index. Mortality risk was assessed using Cox proportional hazards, adjusting for sociodemographic and lifestyle factors, health conditions and influenza and pneumococcal vaccination status. Data were analysed in 2022.ResultsAmong 577 909 participants followed for a median of 9.23 years, 1516 influenza and pneumonia deaths were recorded. Compared with participants meeting neither guideline, those meeting both guidelines had 48% lower adjusted risk of influenza and pneumonia mortality. Relative to no aerobic activity, 10–149, 150–300, 301–600 and >600 min/week were associated with lower risk (by 21%, 41%, 50% and 41%). Relative to ConclusionsAerobic physical activity, even at quantities below the recommended level, may be associated with lower influenza and pneumonia mortality while muscle-strengthening activity demonstrated a J-shaped relationship.

Commercially-available location-based services (LBS) data derived primarily from mobile devices may provide an alternative to surveys for monitoring physically-active transportation. Using Spearman correlation, we compared county-level metrics of walking and bicycling from StreetLight with metrics of physically-active commuting among U.S. workers from the American Community Survey. Our strongest pair of metrics ranked counties (n=298) similarly for walking (rho=0.53 [95% CI: 0.44–0.61]) and bicycling (rho=0.61 [0.53–0.67]). Correlations were higher for denser and more urban counties. LBS data may offer public health and transportation professionals timely information on walking and bicycling behavior at finer geographic scales than some existing surveys.

The COVID-19 pandemic prompted built environment changes throughout the United States. We assessed the prevalence of new places and changed spaces for physical activity as observed by US adults and their intentions to use them. We used data from SummerStyles, a web-based survey of US adults conducted in June 2021 (n = 4073). Respondents were asked if they had discovered new places to be physically active during the past year, and if changes had been made to streets or outdoor areas to allow additional space for recreating. Those responding "yes" were asked if they intended to use the respective space. We estimated the weighted prevalence of adults who observed new places and changed spaces, and their intended use, by sociodemographic and geographic characteristics, physical activity level, and walking status. We compared subgroups with prevalence ratios (PR). Overall, 25.0% of US adults reported discovering new places for physical activity, and 25.3% reported changes to streets and outdoor spaces. Intention to use new places and changed spaces exceeded 50% among all sociodemographic and geographic subgroups. Among those reporting changes, adults who were physically inactive compared to those who were sufficiently active had similar intentions to use new places (PR = 0.83; 95% CI = 0.63, 1.10) and changed spaces (PR = 0.90; 95% CI = 0.69, 1.17). Approximately 1 in 4 adults reported discovering new places or changed spaces to support physical activity during the COVID-19 pandemic, and most intended to use these features. Expanding access to such supportive environments may help promote physical activity participation.

This cohort study uses national data to explore the dose-response association between guideline-recommended physical activity and mortality in older adults.

Background Clinical severity of coronavirus disease 2019 (COVID-19) may vary over time; trends in clinical severity at admission during the pandemic among hospitalized patients in the United States have been incompletely described, so a historical record of severity over time is lacking. Methods We classified 466677 hospital admissions for COVID-19 from April 2020 to April 2021 into 4 mutually exclusive severity grades based on indicators present on admission (from most to least severe): Grade 4 included intensive care unit (ICU) admission and invasive mechanical ventilation (IMV); grade 3 included non-IMV ICU and/or noninvasive positive pressure ventilation; grade 2 included diagnosis of acute respiratory failure; and grade 1 included none of the above indicators. Trends were stratified by sex, age, race/ethnicity, and comorbid conditions. We also examined severity in states with high vs low Alpha (B.1.1.7) variant burden. Results Severity tended to be lower among women, younger adults, and those with fewer comorbidities compared to their counterparts. The proportion of admissions classified as grade 1 or 2 fluctuated over time, but these less-severe grades comprised a majority (75%–85%) of admissions every month. Grades 3 and 4 consistently made up a minority of admissions (15%–25%), and grade 4 showed consistent decreases in all subgroups, including states with high Alpha variant burden. Conclusions Clinical severity among hospitalized patients with COVID-19 has varied over time but has not consistently or markedly worsened over time. The proportion of admissions classified as grade 4 decreased in all subgroups. There was no consistent evidence of worsening severity in states with higher vs lower Alpha prevalence.

Introduction: Weather can be a barrier to walking. Understanding how perceptions of weather as a barrier and measured temperature are associated with walking can inform monitoring and promotion strategies. The objective of this study is to examine the association between perceptions of weather as a barrier to walking and measured weather with the volume of leisure and transportation walking. Methods: The 2015 National Health Interview Survey (NHIS) assessed participation in and volume of walking (transportation, leisure) in the past week and frequency of reporting weather as a barrier to walking. Data were collected over the entire year. In 2019, we merged month-specific temperature data from the PRISM climate group with individual NHIS records. We examined associations using logistic (participation) and linear regression models (volume). Results: Participation in walking increased as frequency of reporting weather as a barrier to walking decreased, from ‘almost always’ (transportation: 23%, leisure: 42%) to ‘a little of the time’ (transportation: 40%, leisure: 67%). Among adults reporting walking, walking volume increased as frequency of reporting weather as a barrier decreased from ‘almost always’ (transportation: 51 min/week, leisure: 64 min/week) to ‘never’ (transportation: 69 min/week, leisure: 98 min/week). Month-specific temperature was significantly associated with leisure walking with lower participation at the lowest and highest temperature quintiles, although the strength of the association differed by frequency of reporting weather as a barrier. Conclusions: In general, prevalence and volume of leisure and transportation walking decreased as the perception of weather as a barrier increased. Low and high temperature conditions were also associated with leisure walking participation, particularly among adults with increased perceptions of weather as a barrier. Our findings highlight the importance of including strategies to help adults overcome perceived and actual weather-related barriers in walking promotion efforts.

Background: New or enhanced activity-friendly routes to everyday destinations is an evidence-based approach for increasing physical activity. Although national estimates for some infrastructure features surrounding where one lives and the types of nearby destinations are available, less is known about the places where individuals walk. Methods: A total of 5 types of walking trips (N = 54,034) were defined by whether they began or ended at home (home based [HB]) and trip purpose (HB work, HB shopping, HB social/recreation, HB other, and not HB trip) (2017 National Household Travel Survey). Differences and trends by subgroups in the proportion of each purpose-oriented trip were tested using pairwise comparisons and polynomial contrasts. Results: About 14% of U.S. adults reported ≥1 walking trip on a given day. About 64% of trips were HB trips. There were few differences in prevalence for each purpose by subgroup. For example, prevalence of trips that were not HB decreased significantly with increasing age and increased with increasing education and household income. Conclusions: Given age-related and socioeconomic differences in walking trips by purpose, planners and other professionals may want to consider trip origin and destination purposes when prioritizing investments for the creation of activity-friendly routes to everyday destinations where people live, work, and play.

Background: High levels of sedentary behavior and physical inactivity increase the risk of premature mortality and several chronic diseases. Monitoring national trends and correlates of sedentary behavior and physical inactivity can help identify patterns of risk in the population over time. Methods: The authors used self-reported data from the National Health and Nutrition Examination Surveys (2007/2008–2017/2018) to estimate trends in US adults’ mean daily sitting time, overall, and stratified by levels of leisure-time and multidomain physical activity, and in the joint prevalence of high sitting time (>8 h/d) and physical inactivity. Trends were tested using orthogonal polynomial contrasts. Results: Overall, mean daily sitting time increased by 19 minutes from 2007/2008 (332 min/d) to 2017/2018 (351 min/d) (Plinear Pquadratic Plinear Conclusions: Sitting time among adults increased over the study period but decreased in recent years.

Background: Surveillance of domain-specific physical activity in the United States is lacking. Thus, the authors describe domain-specific moderate to vigorous physical activity (MVPA) in a nationwide sample of US adults. Methods: Participants from the AmeriSpeak panel (n = 2649; 20–75 y; 50% female) completed the Activities Completed Over Time in 24-Hours previous-day recall. The authors estimated average MVPA duration (in hours per day) overall and in major life domains by sex, age, race/ethnicity, and education. They also described the most commonly reported MVPAs and timing of MVPA during the day. Results: Across all life domains, participants reported an average of 2.5 hours per day in MVPA. Most MVPA was accumulated during work (50% of total, 1.2 h/d) and household activities (28%, 0.7 h/d) with less MVPA reported in leisure time (15%, 0.4 h/d). Time reported in MVPA varied by sex, and race/ethnicity (P Conclusions: Work and household activities accounted for 78% of overall MVPA reported, while leisure-time MVPA accounted for only 15% of the total. Encouraging MVPA during leisure time and transportation remain important targets for promoting MVPA in US adults.

Background: Understanding how participation is changing across domains of physical activity is important for monitoring progress and informing promotion efforts. The authors examined changes in physical activity participation in the National Health and Nutrition Examination Survey 2007/2008 to 2017/2018. Methods: The prevalence of inactivity, insufficient activity, and meeting the aerobic physical activity guideline in multidomain physical activity and each domain (leisure time, occupational/household, and transportation) was estimated for each cycle and stratified by selected characteristics. The authors tested trends over time and overall changes (2017/2018 vs 2007/2008). Results: For multidomain physical activity, the prevalence of inactivity decreased linearly; meeting the aerobic guideline increased nonmonotonically, and the 2017/2018 prevalence (68.1%) was higher than 2007/2008 (64.1%). Similar findings were observed for adults aged ≥65 years, non-Hispanic Blacks, Hispanics, high school graduates, and adults with obesity. Domain-specific results varied, but decreasing trends in inactivity and increasing trends in meeting the guideline were consistently observed across subgroups for occupational/household activity. Meeting the guideline through transportation activity was rare. Conclusions: Increases in meeting the guideline and decreases in inactivity in multidomain activity and selected domains are encouraging results, especially among subgroups historically reporting low activity participation. Activity promotion efforts are important to maintain progress, and the transportation domain may be an underutilized source of physical activity.

Background: The National Health Interview Survey is unique among US federal surveillance systems with over 20 years of consistent assessment of muscle-strengthening and aerobic activity. The authors examined trends in the prevalence of US adults who met the muscle-strengthening (2 or more days per week) and the combined muscle-strengthening and aerobic physical activity (at least 150 min/wk of moderate-intensity equivalent activity) guidelines from 1998 to 2018. Methods: The 1998–2018 National Health Interview Survey data were analyzed. Age-adjusted prevalence of meeting the muscle-strengthening and combined aerobic and muscle-strengthening guidelines by selected respondent characteristics were estimated for each year and linear and higher-order trends were assessed. Results: From 1998 to 2018, prevalence of meeting the muscle-strengthening guideline increased from 17.7% to 27.6%, and meeting the combined aerobic and muscle-strengthening guidelines increased from 14.4% to 24.0%. All subgroups demonstrated significant increases in meeting both guideline measures over this period although trends varied across the 21 years; increasing trends were more commonly sustained in the second decade of monitoring. Conclusions: Although increasing trends in prevalence of meeting the muscle-strengthening and combined guidelines are encouraging, current prevalence estimates remain low. Opportunities exist for the continued promotion of muscle-strengthening activity using evidence-based approaches.

Introduction Active commuting to work is one way people can be physically active and can be influenced by state-level initiatives. The American Community Survey (ACS) is a potential data source to evaluate changes in active commuting at the state level, but state-level changes have not been well documented. We examined state-level changes in estimates of walking, biking, and taking transit to work (combined and separately) among employed persons between 2006 and 2017. Methods Data were from the ACS, a nationally representative annual household survey from the US Census Bureau. We estimated state-level prevalence of walking, bicycling, or taking transit to work (separately and in combination) in 2006 and 2017 and tested differences by year. Results The prevalence of active commuting to work varied widely among states (2017 range: 1.7% in Alabama and Mississippi to 35.0% in New York). Changes from 2006 to 2017 also varied, with 8 states exhibiting a significant increase (Massachusetts [2.7 percentage points], New York [2.2], Hawaii [1.6], Illinois [1.3], Washington [1.3], New Jersey [1.2], Virginia [0.9], and Michigan [0.4]), and 12 exhibiting a significant decrease (South Dakota [−1.9], Idaho [−1.3], New Hampshire [−1.3], Wisconsin [−1.1], Maryland [−1.0], Nevada [−0.9], Ohio [−0.8], Mississippi [−0.6], Texas [−0.6], Florida [−0.5], Georgia [−0.4], and Indiana [−0.4]). The contributions of walking, bicycling, and taking transit also varied by state. Conclusion Active commuting remains relatively rare across states. States pursuing initiatives to support active transportation may consider using ACS to monitor and evaluate changes in active commuting.

Physical activity occurs in 4 domains (leisure, occupational, household, and transportation), but US surveillance often focuses on leisure-time only. We compared estimates of self-reported leisure-time physical activity and estimates of all-domain activity among adults in the National Health and Nutrition Examination Survey for 2011–2016. During the study period, 38.6% met the aerobic physical activity guideline in leisure-time, 58.5% in leisure-time and occupational/household activity, and 63.7% in all domains. Differences within most subgroups when using all domains were similar to differences when using leisure-time activity only, except that we observed no urban/rural differences in the multidomain assessment. Assessment of multiple domains of activity instead of leisure-time–only activity affects prevalence estimates to a greater extent than it affects subgroup differences.

BackgroundEmerging evidence, predominately from European and Asian countries, describes opposing effects of occupational physical activity (OPA) and leisure-time physical activity (LTPA) on cardiovascular health. This analysis examined cardiovascular disease (CVD) prevalence associated with OPA and LTPA.MethodsThis cross-sectional analysis of 2015 National Health Interview Survey data (n=16 974) employed logistic regression to estimate odds (OR) of self-reported CVD (coronary heart disease, heart attack, stroke or angina) with self-reported total occupational activity (TOA), occupational exertion (OE), occupational standing and walking (OSW) and LTPA. OPA was measured using two questions: ‘How often does your job involve…’ (1) ‘repeated lifting, pushing, pulling or bending?’ (OE) and (2) ‘standing or walking around?’ (OSW) with responses on a 5-item Likert scale (0=never, 4=always). TOA was categorised similarly after summing OE and OSW scores. LTPA was defined as 0, 1–149 or ≥150 min/week of moderate-to-vigorous activity. All models adjusted for common socioeconomic variables and additional analyses were stratified by sex, smoking status and LTPA.ResultsOdds for CVD were higher when ‘always’ performing TOA (OR 1.99 95% CI 1.12 to 3.53), OE (OR 2.15, 95% CI 1.45 to 3.19) or OSW (OR 1.84, 95% CI 1.07 to 3.17) compared with ‘never’. When restricting to never-smokers, odds for CVD were higher when ‘always’ performing TOA (OR 3.00, 95% CI 1.38 to 6.51) and OE (OR 3.00, 95% CI 1.80 to 5.02) versus ‘never’.ConclusionAssociations of high OPA with CVD were equally apparent across sexes, stronger in lower LTPA levels and stronger in never-smokers. While uncontrolled confounding is still possible, even after extensive adjustment, the seemingly paradoxical adverse associations with OPA and CVD should be investigated further.

The Environmental Protection Agency created the National Walkability Index (Index) to compare and analyze walkability among US communities. Index elements include design, distance to transit, and diversity of land uses. Associations between the Index and walking behavior have not been examined. This study describes associations between the Index and transportation and leisure walking among US adults. Past week self-reported participation in transportation and leisure walking among adults (n = 33,672) was obtained from the 2015 Cancer Control Supplement of the National Health Interview Survey (NHIS) and analysis completed in 2019. Index scores were linked to NHIS data based on the respondent's residence and classified into least, below average, above average, and most walkable communities. Associations between Index categories and walking were examined with regression models. Overall, the Index was associated with a higher likelihood of walking, especially for transportation. Transportation walking was more common in areas with higher walkability (21.6%–51.6%, least to most walkable). Leisure walking was also more common with greater walkability (48.4%–56.5%, least to most walkable). Transportation and leisure walking by Index categories in urban areas were similar to the overall population; however, it was not associated with walking in rural areas. US adults living in more walkable areas report more transportation and leisure walking, especially among urban areas. Consistent with elements in the Index, associations were stronger for transportation than leisure walking. Findings support the use of the Walkability Index by researchers, professionals, and other relevant stakeholders as a viable indicator of walkability.

Introduction Walking can serve many purposes, such as transportation (to get some place) or leisure (for fun, relaxation, or exercise); therefore, it provides many opportunities for people to be physically active. This study examines geographic and urban–rural differences in walking in the U.S. Methods Adult respondents (aged ≥18 years) to the 2015 National Health Interview Survey reported participation in and time spent (minutes per week) walking for transportation and leisure in the past week. In 2017, prevalence and time spent walking (among walkers) for any, leisure, and transportation walking were estimated by nine expanded regions and urban–rural designation. Results Prevalence of any walking ranged from 50.8% (East South Central) to 72.4% (Pacific); for leisure walking 43.9% (East South Central) to 60.6% (Pacific); and transportation walking 17.8% (East South Central) to 43.5% (New England). Among walkers, mean minutes spent walking per week ranged from 77.4 (East South Central) to 101.6 (Pacific); for leisure walking 70.5 (West South Central) to 85.9 (Mountain); and for transportation walking 47.4 (East South Central) to 66.4 (Middle Atlantic). Overall, there were urban–rural differences in prevalence of walking; however, differences depended on walking purpose and expanded region. Time spent walking was similar in urban and rural areas. Conclusions Regional differences in walking prevalence and time spent walking exist. Urban–rural differences in prevalence of walking differ based on region and purpose; however, rural areas had a lower prevalence of walking than urban areas regardless of purpose in southern regions. Opportunities exist to improve walking, particularly among southern regions with a focus on rural areas.

Active transportation (AT), or walking or bicycling for transportation, represents one way individuals can achieve recommended physical activity (PA) levels. This study describes AT prevalence and temporal trends, and examines associations between AT levels and measured CVD risk factors (hypertension, hypercholesterolemia, low high-density [HDL] cholesterol, diabetes, and obesity) among U.S. adults. National Health and Nutrition Examination Survey (NHANES) 2007–2016 data (analyzed in 2017) were used to conduct overall trend analyses of reported AT in a typical week [none (0–9 min/week); low (10–149 min/week); or high (≥150 min/week)]. Logistic regression was used to examine associations between AT level and each CVD risk factor from NHANES 2011–2016 (n = 13,943). Covariates included age, sex, race/Hispanic origin, education, income, smoking, survey cycle, non-transportation PA, and urbanization level. U.S. adults who engaged in high AT levels increased from 13.1% in 2007–2008 to 17.9% in 2011–2012, and then decreased to 10.6% in 2015–2016 (p for quadratic trend = 0.004). Over the same period, the quadratic trend for low AT was not significant. During 2011–2016, 14.3% of adults engaged in high AT, 11.4% in low AT, and 74.4% in no AT. High AT levels were associated with decreased odds of each CVD risk factor assessed, compared to no AT. Low AT (versus no AT) was associated with decreased odds of hypertension (aOR = 0.77, 95% CI 0.64, 0.91) and diabetes (aOR = 0.68, 95% CI 0.54, 0.85). AT prevalence among adults has fluctuated from 2007 to 2016. Despite favorable associations between AT and CVD risk factors, most U.S. adults do not engage in any AT.

Promotion of walking is a promising strategy for increasing physical activity levels in the U.S. The proportion of adults who report walking for either transportation or leisure has increased in recent years, but evidence on trends in walking for specific purposes is limited.The 2005, 2010, and 2015 National Health Interview Survey assessed self-reported participation in and volume (minutes/week) of walking for transportation and leisure in the past week among adults aged ≥18 years. Linear and quadratic trends in the prevalence and mean volume of walking for each purpose were evaluated using logistic and linear regression. Analyses were performed in 2017.The prevalence of transportation walking increased from 28.4% (2005) to 31.7% (2015) (linear trend: p0.05). Leisure walking prevalence increased from 42.1% (2005) to 52.1% (2015), but the increased stalled from 2010 to 2015 with only a 2.3 percentage point increase (linear and quadratic trends: p0.05). Across purposes, the mean walking volume decreased from 2005 to 2015, with no significant changes between 2010 and 2015 (linear and quadratic trends: p0.05). The proportion of adults who walked for both transportation and leisure in the past week increased steadily (linear trend: p0.05), and this group reported the greatest total volume of walking.Although the prevalence of self-reported transportation and leisure walking increased during the last decade, the time spent walking decreased. Strategies that encourage walking for multiple purposes may present an opportunity for increasing both participation in walking and the amount of time spent walking.

Introduction The Guide to Community Preventive Services recommends combined built environment approaches to increase physical activity, including new or enhanced transportation infrastructure (e.g., sidewalks) and land use and environmental design interventions (e.g., close proximity of local destinations). The aim of this brief report is to provide nationally representative estimates of two types of built environment supports for physical activity: near-home walkable infrastructure and destinations, from the 2015 National Health Interview Survey. Methods Adults ( n =30,453) reported the near-home presence of walkable transportation infrastructure (roads, sidewalks, paths, or trails where you can walk; and whether most streets have sidewalks) and four walkable destination types (shops, stores, or markets; bus or transit stops; movies, libraries, or churches; and places that help you relax, clear your mind, and reduce stress). The prevalence of each, and the count of destination types, was calculated (in 2017) and stratified by demographic characteristics. Results Overall, 85.1% reported roads, sidewalks, paths, or trails on which to walk, and 62.6% reported sidewalks on most streets. Among destinations, 71.8% reported walkable places to relax; followed by shops (58.0%); transit stops (53.2%); and movies, libraries, or churches (47.5%). For most design elements, prevalence was similar among adults aged 18–24 and 25–34 years, but decreased with age >35 years. Adults in the South reported a lower prevalence of all elements compared with those in other Census regions. Conclusions Many U.S. adults report walkable built environment elements near their home; future efforts might target areas with many older adult residents or those living in the South.

People with disabilities are at increased risk of chronic diseases, many of which physical activity can help prevent and manage. Certain environmental features can support or hinder participation in important activities like walking, particularly for people with disabilities. The purpose of this study is to examine differences in the prevalence of perceived neighborhood environmental supports and barriers for walking, by disability status, among US adults. Participants in the 2015 National Health Interview Survey Cancer Control Supplement (N = 15,280) reported their disability status (mobility disability, non-mobility disability, or no disability) and perceptions of neighborhood environmental supports (walkable roads, sidewalks, paths, trails; sidewalks on most streets; and walkable shops; transit; movies, libraries, churches; relaxing places) and barriers (traffic, crime, animals) for walking. Adjusted models conducted in 2019 included demographic characteristics. Prevalence of most supports was lower among adults with mobility or non-mobility disabilities versus no disability. For example, 54.9% and 57.5% of adults with mobility and non-mobility disabilities respectively reported sidewalks on most streets, compared to 64.1% of adults with no disability. After adjustment, significant differences remained when comparing adults with a mobility disability versus no disability for two supports (roads, sidewalks, paths, trails; relaxing places). All perceived barriers were significantly more common among adults with any disability versus no disability, regardless of adjustment. In the United States, adults with disabilities perceive fewer neighborhood environmental supports and more barriers for walking than their counterparts. Strategies that increase supports and address barriers for walking may help promote physical activity among adults with disabilities.

Since the release of the 2008 Physical Activity Guidelines for Americans (https://health.gov/paguidelines/2008/pdf/paguide.pdf), the age-adjusted percentage of adults meeting the combined aerobic and muscle-strengthening guidelines increased from 18.2% to 24.3% in 2017 (1). Trends in urban and rural areas, across demographic subgroups, and among subgroups within urban and rural areas have not been reported. CDC analyzed 2008-2017 National Health Interview Survey (NHIS) data to examine trends in the age-standardized prevalence of meeting physical activity guidelines among adults aged ≥18 years living in urban and rural areas. Among urban and rural residents, prevalence increased from 19.4% to 25.3% and from 13.3% to 19.6%, respectively. Nationally, all demographic subgroups and regions experienced increases over this period; increases for several groups were not consistent year-to-year. Among urban residents, the prevalence was higher during 2016-2017 than during 2008-2009 for all demographic subgroups and regions. During the same period, prevalence was higher across all rural-dwelling subgroups except Hispanics, adults with a college education, and those living in the South U.S. Census region. Urban and rural communities can implement evidence-based approaches, including improved community design, improved access to indoor and outdoor recreation facilities, social support programs, and community-wide campaigns to make physical activity the safe and easy choice for persons of all ages and abilities (2-4). Incorporating culturally appropriate strategies into local programs might help address differences across subgroups.

Built environments that provide activity-friendly routes (e.g., sidewalks) to everyday destinations (e.g., shops) can increase physical activity. Surveillance of supports and destinations is important, and identifying which are associated with walking could prioritize surveillance questions. Our purpose was to identify the significant associations between supports and destinations with walking among a nationally-representative sample of urban- and rural-dwelling adults. Participants in the 2015 National Health Interview Survey, Cancer Control Supplement (n = 29,925) reported the near-home presence of walkable supports (roads, sidewalks, paths, or trails; sidewalks on most streets), destinations (shops; transit; movies, libraries, or churches; relaxing places), and past-week walking for leisure or transportation. We used stepwise logistic regression to quantify associations between supports and destinations and walking, including by urban/rural residence. We calculated the prevalence of walking across counts of reported elements by urban/rural residence. Among all participants, roads, sidewalks, paths, or trails and relaxing destinations were associated with leisure walking. Among urban residents, sidewalks on most streets and all four destination types were associated with transportation walking; among rural residents, roads, sidewalks, paths, or trails; movies, libraries, or churches; and relaxing destinations were associated with transportation walking. Walking was more common when more environmental elements were reported. To improve efficiency, communities may match surveillance priorities to behavioral priorities (i.e., leisure versus transportation walking) and environmental context (i.e., urban/rural areas). Surveillance of environments supporting leisure walking might focus on recreation-oriented spaces. Surveillance of environments supporting transportation walking might differ for urban and rural areas, and assessing destinations may be particularly important.

Barriers to safe walking may prevent people from being physically active, and previous reports have identified differences in barriers to safe walking across racial and ethnic groups. The purpose of this research was to determine the role demographic characteristics play on racial/ethnic differences in perceived barriers to safe walking and determine if racial/ethnic differences vary by urban/rural residence and Census region. Participants in the 2015 National Health Interview Survey Cancer Control Supplement (n = 31,433 adults ≥18 years) reported perceived barriers to safe walking (traffic, crime, and animals) and demographic characteristics. Urban/rural residence and Census region were based on home addresses. We calculated adjusted prevalence of barriers by race/ethnicity using logistic regression; geographic differences in barriers across racial/ethnic groups were examined via interaction terms. After adjustment for demographic characteristics, non-Hispanic blacks (blacks) and Hispanics reported crime and animals as barriers more frequently than non-Hispanic whites (whites) (crime: blacks, 22.2%; Hispanics, 16.7%; whites, 9.0%; animals: blacks, 18.0%; Hispanics, 12.4%; whites, 8.5%). Racial/ethnic differences in perceived crime as a barrier were more pronounced in the Northeast and Midwest than in the South and West. Urban-dwelling blacks (all regions) and Hispanics (Midwest and South) reported animals as barriers more frequently than whites. Racial/ethnic differences in perceived barriers to safe walking remained after adjusting for demographic characteristics and varied by geographic location. Addressing perceived crime and animals as barriers to walking could help reduce racial/ethnic differences in physical activity, and several barriers may need to be assessed to account for geographic variation.

PROBLEM/CONDITION: Physical activity is a health-enhancing behavior, and most U.S. adults do not meet the 2008 Physical Activity Guidelines for Americans. Active transportation, such as by walking or bicycling, is one way that persons can be physically active. No comprehensive, multiyear assessments of active transportation surveillance in the United States have been conducted. PERIOD COVERED: 1999-2012. DESCRIPTION OF SYSTEMS: Five surveillance systems assess one or more components of active transportation. The American Community Survey and the National Household Travel Survey (NHTS) both assess the mode of transportation to work in the past week. From these systems, the proportion of respondents who reported walking or bicycling to work can be calculated. NHTS and the American Time Use Survey include 1-day assessments of trips or activities. With that information, the proportion of respondents who report any walking or bicycling for transportation can be calculated. The National Health and Nutrition Examination Survey and the National Health Interview Survey both assess recent (i.e., in the past week or past month) habitual physical activity behaviors, including those performed during active travel. From these systems, the proportion of respondents who report any recent habitual active transportation can be calculated. RESULTS: The prevalence of active transportation as the primary commute mode to work in the past week ranged from 2.6% to 3.4%. The 1-day assessment indicated that the prevalence of any active transportation ranged from 10.5% to 18.5%. The prevalence of any habitual active transportation ranged from 23.9% to 31.4%. No consistent trends in active transportation across time periods and surveillance systems were identified. Among systems, active transportation was usually more common among men, younger respondents, and minority racial/ethnic groups. Among education groups, the highest prevalence of active transportation was usually among the least or most educated groups, and active transportation tended to be more prevalent in densely populated, urban areas. INTERPRETATION: Active transportation is assessed in a wide variety of ways in multiple surveillance systems. Different assessment techniques and construct definitions result in widely discrepant estimates of active transportation; however, some consistent patterns were detected across covariates. Although each type of assessment (i.e., transportation to work, single day, and habitual behavior) measures a different active transportation component, all can be used to monitor population trends in active transportation participation. PUBLIC HEALTH ACTION: An understanding of the strengths, limitations, and lack of comparability of active transportation assessment techniques is necessary to correctly evaluate findings from the various surveillance systems. When used appropriately, these systems can be used by public health and transportation professionals to monitor population participation in active transportation and plan and evaluate interventions that influence active transportation. Language: en

AB Introduction: The association between aerobic physical activity volume and bone mineral density (BMD) is not completely understood. The purpose of this study was to clarify the association between BMD and aerobic activity across a broad range of activity volumes, particularly volumes between those recommended in the 2008 Physical Activity Guidelines for Americans and those of trained endurance athletes. Methods: Data from the 2007-2010 National Health and Nutrition Examination Survey were used to quantify the association between reported physical activity and BMD at the lumbar spine and proximal femur across the entire range of activity volumes reported by US adults. Participants were categorized into multiples of the minimum guideline-recommended volume based on reported moderate- and vigorous-intensity leisure activity. Lumbar and proximal femur BMD were assessed with dual-energy x-ray absorptiometry. Results: Among women, multivariable-adjusted linear regression analyses revealed no significant differences in lumbar BMD across activity categories, whereas proximal femur BMD was significantly higher among those who exceeded the guidelines by 2-4 times than those who reported no activity. Among men, multivariable-adjusted BMD at both sites neared its highest values among those who exceeded the guidelines by at least 4 times and was not progressively higher with additional activity. Logistic regression estimating the odds of low BMD generally echoed the linear regression results. Conclusions: The association between physical activity volume and BMD is complex. Among women, exceeding guidelines by 2-4 times may be important for maximizing BMD at the proximal femur, whereas among men, exceeding guidelines by >=4 times may be beneficial for lumbar and proximal femur BMD.

Physical activity confers considerable health benefits, but only half of U.S. adults report participating in levels of aerobic physical activity consistent with guidelines (1,2). Step It Up! The Surgeon General's Call to Action to Promote Walking and Walkable Communities identified walking as an important public health strategy to increase physical activity levels (3). A previous report showed that the self-reported prevalence of walking for transportation or leisure increased by 6 percentage points from 2005 to 2010 (4), but it is unknown whether this increase has been sustained. CDC analyzed National Health Interview Survey (NHIS) data from 2005 (26,551 respondents), 2010 (23,313), and 2015 (28,877) to evaluate trends in the age-adjusted prevalence of self-reported walking among adults aged ≥18 years. The prevalence of walking increased steadily among women, from 57.3% in 2005, to 62.5% in 2010, and to 65.1% in 2015 (significant linear trend). Among men, a significant linear increase in reported walking was observed, from 54.3% in 2005, to 61.8% in 2010, and to 62.8% in 2015, although the increase stalled between 2010 and 2015 (significant linear and quadratic trends). Community design policies and practices that encourage pedestrian activity and programs tailored to the needs of specific population subgroups remain important strategies for promoting walking (3).

PURPOSE For most people, the benefits of physical activity far outweigh the risks. Research has suggested that exercise preparticipation questionnaires might refer an unwarranted number of adults for medical evaluation before exercise initiation, creating a potential barrier to adoption. The new American College of Sports Medicine (ACSM) prescreening algorithm relies on current exercise participation; history and symptoms of cardiovascular, metabolic, or renal disease; and desired exercise intensity to determine referral status. Our purpose was to compare the referral proportion of the ACSM algorithm to that of previous screening tools using a representative sample of U.S. adults. METHODS On the basis of responses to health questionnaires from the 2001-2004 National Health and Nutrition Examination Survey, we calculated the proportion of adults 40 yr or older who would be referred for medical clearance before exercise participation based on the ACSM algorithm. Results were stratified by age and sex and compared with previous results for the ACSM/American Heart Association Preparticipation Questionnaire and the Physical Activity Readiness Questionnaire. RESULTS On the basis of the ACSM algorithm, 2.6% of adults would be referred only before beginning vigorous exercise and 54.2% of respondents would be referred before beginning any exercise. Men were more frequently referred before vigorous exercise, and women were more frequently referred before any exercise. Referral was more common with increasing age. The ACSM algorithm referred a smaller proportion of adults for preparticipation medical clearance than the previously examined questionnaires. CONCLUSIONS Although additional validation is needed to determine whether the algorithm correctly identifies those at risk for cardiovascular complications, the revised ACSM algorithm referred fewer respondents than other screening tools. A lower referral proportion may mitigate an important barrier of medical clearance from exercise participation.

The Nashville Area Metropolitan Planning Organization (MPO) is among the first MPOs in the United States to recognize the interplay of transportation and public health, particularly regarding physical activity, air pollution, and traffic crashes. The Nashville MPO has taken a multifaceted approach to simultaneously improve the transportation system, quality of life, and health status of the region's population. The purpose of this paper is to describe the multiple programs and projects that the MPO has undertaken to this end, so that other cities might learn from Nashville's example. The MPO's strategy comprised six processes. First, the MPO conducted the Regional Bicycle and Pedestrian Study in 2009 and 2014 that established priority issues to be addressed by bicycle and pedestrian projects in Regional Transportation Plans. Second, the MPO responded to public opinion by adopting new transportation policies in the 2035 and 2040 Regional Transportation Plans, including increasing bicycle and pedestrian options and expanding public transit. Third, the MPO created scoring criteria for proposed roadway projects that prioritized health impacts. Fourth, the MPO reserved funding for projects selected under the new criteria and established a new funding program, the Active Transportation Program. Fifth, the MPO conducted the Middle Tennessee Transportation and Health Study, one of the first regional studies in the nation linking transportation and health. Finally, the MPO implemented the Integrated Transport and Health Impact Model which predicts and monetizes population-level health impacts of shifting the population towards active transportation modes. Recent inventories of bicycle and pedestrian infrastructure suggest these interrelated processes are increasing opportunities for walking, bicycling, and public transit use in the region. Further, each of these projects has contributed to a growing appreciation in the region of the links between transportation and health, and continued evaluation efforts can determine if transportation behaviors and health outcomes are changing.

Background— Although the American Heart Association/American College of Sports Medicine’s Preparticipation Questionnaire (AAPQ) is a recommended preexercise cardiovascular screening tool, it has never been systematically evaluated. The purpose of this research is to provide preliminary evidence of its effectiveness among adults aged ≥40 years. Methods and Results— Under the assumption that participants would respond to AAPQ items as they responded to a general health survey, we calculated the sex- and age-specific proportions of adult participants in the National Health and Nutrition Examination Survey 2001 to 2004 who would receive a recommendation for physician consultation based on AAPQ referral criteria. Additionally, we compared recommended AAPQ referrals to a similar assessment using the Physical Activity Readiness Questionnaire in the study sample. AAPQ referral proportions were higher with older age. Across all age groups ≥40 years, 95.5% (94.3% to 96.8%) of women and 93.5% (92.2% to 94.7%) of men in the United States would be advised to consult a physician before exercise. Prescription medication use and age were the most commonly selected items. When referral based on AAPQ was compared with that of the Physical Activity Readiness Questionnaire, the 2 screening tools produced similar results for 72.4% of respondents. Conclusions— These results suggest that >90% of US adults aged ≥40 years would receive a recommendation for physician consultation by the AAPQ. Excessive referral may present an unnecessary barrier to exercise adoption and stress the healthcare infrastructure.

Background:Emerging evidence suggests that combined physical activity (PA) and inactivity may be more important for chronic disease risk than PA alone. A highly active yet highly sedentary population is needed to study this interaction. The present purpose is to describe the sitting habits of a group of recreational runners and determine if sitting varies with reported training duration or anticipated running velocity.Methods:Marathon and half-marathon participants completed the Multicontext Sitting Time Questionnaire and reported peak training duration, anticipated finishing time, and demographic information. Sitting time was described across 5 contexts for workdays and nonworkdays. Total sitting time was analyzed by tertiles of training duration and anticipated event running velocity.Results:218 participants took part in this study. Median reported training time was 6.5 hours per week. Median total sitting time was higher on workdays than nonworkdays (645 and 480 minutes, respectively, P < .0001). Total sitting time was not associated with training duration or anticipated event running velocity.Conclusions:These results suggest that recreational distance runners are simultaneously highly sedentary and highly active, supporting independence of sedentary behaviors and moderate- to vigorous-intensity PA. This population may provide the characteristics needed to study the joint effects of active and sedentary behaviors on health outcomes.

Creating environments that support all types of physical activity, including active transportation, is a public health priority (1). Public health surveillance that identifies the locations where community members walk and bicycle (i.e., engage in active transportation) can inform such efforts. Traditional population-representative active transportation surveillance incurs a considerable time lag between data collection and dissemination, and often lacks geographic specificity (2). Conversely, user-generated active transportation data from Global Positioning System (GPS)-based activity tracking devices and mobile applications can provide near real-time information, but might be subject to self-selection bias among users. CDC analyzed the association between GPS-based commuting data from a company that allows tracking of activity with a mobile application (Strava, Inc., San Francisco, California) and population-representative commuting data from the U.S. Census Bureau's American Community Survey (ACS) (3) for four U.S. cities. The level of analysis was the Census block group. The number of GPS-tracked commuters in Strava was associated with the number of ACS active commuters (Spearman's rho = 0.60), suggesting block groups were ranked similarly based on these distinct but related measurements. The correlation was higher in high population density areas. User-generated active transportation data might complement traditional surveillance systems by providing near real-time, location-specific information on where active transportation occurs.

The Integrated Transport and Health Impact Model (ITHIM) is a comprehensive tool that estimates the hypothetical health effects of transportation mode shifts through changes to physical activity, air pollution, and injuries. The purpose of this paper is to describe the implementation of ITHIM in greater Nashville, Tennessee (USA), describe important lessons learned, and serve as an implementation guide for other practitioners and researchers interested in running ITHIM. As might be expected in other metropolitan areas in the US, not all the required calibration data was available locally. We utilized data from local, state, and federal sources to fulfill the 14 ITHIM calibration items, which include disease burdens, travel habits, physical activity participation, air pollution levels, and traffic injuries and fatalities. Three scenarios were developed that modeled stepwise increases in walking and bicycling, and one that modeled reductions in car travel. Cost savings estimates were calculated by scaling national-level, disease-specific direct treatment costs and indirect lost productivity costs to the greater Nashville population of approximately 1.5 million. Implementation required approximately one year of intermittent, part-time work. Across the range of scenarios, results suggested that 24 to 123 deaths per year could be averted in the region through a 1%-5% reduction in the burden of several chronic diseases. This translated into $10-$63 million in estimated direct and indirect cost savings per year. Implementing ITHIM in greater Nashville has provided local decision makers with important information on the potential health effects of transportation choices. Other jurisdictions interested in ITHIM might find the Nashville example as a useful guide to streamline the effort required to calibrate and run the model.

We conducted an ecological study to determine whether parking prices are associated with active commuting across US cities. We obtained parking prices for 107 US cities from the Drexel University Central Business District Public Parking Survey, obtained city prevalence of walking and bicycling to work from the American Community Survey, and used weighted least squares linear regression to explore associations between parking prices and active commuting. After adjusting for several covariates, walking to work was 3.1% higher for every additional dollar charged for off-street daily parking, but only among more densely populated cities, and no such association was detected for bicycling to work. These preliminary results hint at the potential for parking policies to influence commuting mode choice, a link that city planners and public health officials could consider when evaluating parking policies and active transportation behaviors. Language: en

Physical activity is a health-enhancing behavior, and most U.S. adults do not meet the 2008 Physical Activity Guidelines for Americans. Active transportation, such as by walking or bicycling, is one way that persons can be physically active. No comprehensive, multiyear assessments of active transportation surveillance in the United States have been conducted.1999-2012.Five surveillance systems assess one or more components of active transportation. The American Community Survey and the National Household Travel Survey (NHTS) both assess the mode of transportation to work in the past week. From these systems, the proportion of respondents who reported walking or bicycling to work can be calculated. NHTS and the American Time Use Survey include 1-day assessments of trips or activities. With that information, the proportion of respondents who report any walking or bicycling for transportation can be calculated. The National Health and Nutrition Examination Survey and the National Health Interview Survey both assess recent (i.e., in the past week or past month) habitual physical activity behaviors, including those performed during active travel. From these systems, the proportion of respondents who report any recent habitual active transportation can be calculated.The prevalence of active transportation as the primary commute mode to work in the past week ranged from 2.6% to 3.4%. The 1-day assessment indicated that the prevalence of any active transportation ranged from 10.5% to 18.5%. The prevalence of any habitual active transportation ranged from 23.9% to 31.4%. No consistent trends in active transportation across time periods and surveillance systems were identified. Among systems, active transportation was usually more common among men, younger respondents, and minority racial/ethnic groups. Among education groups, the highest prevalence of active transportation was usually among the least or most educated groups, and active transportation tended to be more prevalent in densely populated, urban areas.Active transportation is assessed in a wide variety of ways in multiple surveillance systems. Different assessment techniques and construct definitions result in widely discrepant estimates of active transportation; however, some consistent patterns were detected across covariates. Although each type of assessment (i.e., transportation to work, single day, and habitual behavior) measures a different active transportation component, all can be used to monitor population trends in active transportation participation.An understanding of the strengths, limitations, and lack of comparability of active transportation assessment techniques is necessary to correctly evaluate findings from the various surveillance systems. When used appropriately, these systems can be used by public health and transportation professionals to monitor population participation in active transportation and plan and evaluate interventions that influence active transportation.