BAILA: A Randomized Controlled Trial of Latin Dancing to Increase Physical Activity in Spanish-Speaking Older Latinos.

BACKGROUND: Latinos are the fastest growing minority group of the older adult population. Although physical activity (PA) has documented health benefits, older Latinos are less likely to engage in leisure time PA than older non-Latino whites. Dance, popular among Latinos, holds promise as a culturally relevant form of PA. PURPOSE: To describe self-reported and device-assessed changes in PA as a result of a randomized controlled trial of BAILAMOS, a 4-month Latin dance program with a 4-month maintenance program, versus a health education control group. METHODS: Adults, aged 55+, Latino/Hispanic, Spanish speaking, with low PA levels at baseline, and risk for disability were randomized to the dance program (n = 167) or health education condition (n = 166). Data were analyzed using multilevel modeling with full information maximum likelihood. RESULTS: A series of multilevel models revealed significant time × group interaction effects for moderate-to-vigorous physical activity (MVPA), dance PA, leisure PA, and total PA. Exploring the interaction revealed the dance group to significantly increase their MVPA, dance PA, leisure PA, and total PA at months 4 and 8. Household PA and activity counts from accelerometry data did not demonstrate significant interaction effects. CONCLUSIONS: The study supports organized Latin dance programs to be efficacious in promoting self-reported PA among older Latinos. Efforts are needed to make dancing programs available and accessible, and to find ways for older Latinos to add more PA to their daily lives. CLINICAL TRIAL INFORMATION: NCT01988233.

Determinants, circumstances and consequences of injurious falls among older women living in the community.

OBJECTIVE: To identify the risk factors of women who fell with injury relative to women who did not fall or fell without injury and to describe the circumstances and consequences of injurious and non-injurious falls. METHODS: We analysed 5074 older women from the Objective Physical Activity and Cardiovascular Health Study who prospectively tracked their falls using a 13-month calendar. Women with a reported fall were phone interviewed about fall-related details, including injuries. Risk factors were identified from surveys and clinical home visits. Logistic regression models were used to calculate adjusted ORs and 95% CIs for injurious falls relative to not falling or falling without injury. Circumstances of injurious and non-injurious falls were compared. RESULTS: At least one fall was experienced by 1481 (29%) participants. Of these, 1043 were phone interviewed, of whom 430 (41%) reported at least one injurious fall. Relative to not falling, the risk factor most strongly associated with experiencing an injurious fall was having fallen ≥2 times (OR 4.0, CI 2.7 to 5.8) in the past year. Being black was protective for fall-related injury (OR 0.6, CI 0.4 to 0.9). No strong associations in risk factors were observed for injurious relative to non-injurious falls. Injurious falls were more likely to occur away from and outside of the home (p<0.05). Over half of those who injured self-managed their injury. CONCLUSION: Falling repeatedly is a powerful risk factor for injurious falls. Those who have fallen more than once should be prioritised for interventions to mitigate the risk of an injurious fall.

Sedentary behavior and cardiovascular disease in older women: The Objective Physical Activity and Cardiovascular Health (OPACH) Study.

Background: Evidence that higher sedentary time is associated with higher risk for cardiovascular disease (CVD) is based mainly on self-reported measures. Few studies have examined whether patterns of sedentary time are associated with higher risk for CVD. Methods: Women from the Objective Physical Activity and Cardiovascular Health (OPACH) Study (n=5638, aged 63-97, mean age=79±7) with no history of myocardial infarction (MI) or stroke wore accelerometers for 4-to-7 days and were followed for up to 4.9 years for CVD events. Average daily sedentary time and mean sedentary bout duration were the exposures of interest. Cox regression models estimated hazard ratios (HR) and 95% confidence intervals (CI) for CVD using models adjusted for covariates and subsequently adjusted for potential mediators (body mass index (BMI), diabetes, hypertension, and CVD-risk biomarkers [fasting glucose, high-density lipoprotein, triglycerides, and systolic blood pressure]). Restricted cubic spline regression characterized dose-response relationships. Results: There were 545 CVD events during 19,350 person-years. Adjusting for covariates, women in the highest (≥ ~11 hr/day) vs. the lowest (≤ ~9 hr/day) quartile of sedentary time had higher risk for CVD (HR=1.62; CI=1.21-2.17; p-trend <0.001). Further adjustment for potential mediators attenuated but did not eliminate significance of these associations (p-trend<.05, each). Longer vs. shorter mean bout duration was associated with higher risks for CVD (HR=1.54; CI=1.27-2.02; p-trend=0.003) after adjustment for covariates. Additional adjustment for CVD-risk biomarkers attenuated associations resulting in a quartile 4 vs. quartile 1 HR=1.36; CI=1.01-1.83; p-trend=0.10). Dose-response associations of sedentary time and bout duration with CVD were linear (P-nonlinear >0.05, each). Women jointly classified as having high sedentary time and long bout durations had significantly higher risk for CVD (HR=1.34; CI=1.08-1.65) than women with both low sedentary time and short bout duration. All analyses were repeated for incident coronary heart disease (MI or CVD death) and associations were similar with notably stronger hazard ratios. Conclusions: Both high sedentary time and long mean bout durations were associated in a dose-response manner with increased CVD risk in older women, suggesting that efforts to reduce CVD burden may benefit from addressing either or both component(s) of sedentary behavior.

Predicting Risk of Type 2 Diabetes by Using Data on Easy-to-Measure Risk Factors.

INTRODUCTION: Statistical models for assessing risk of type 2 diabetes are usually additive with linear terms that use non-nationally representative data. The objective of this study was to use nationally representative data on diabetes risk factors and spline regression models to determine the ability of models with nonlinear and interaction terms to assess the risk of type 2 diabetes. METHODS: We used 4 waves of data (2005-2006 to 2011-2012) on adults aged 20 or older from the National Health and Nutrition Examination Survey (n = 5,471) and multivariate adaptive regression splines (MARS) to build risk models in 2015. MARS allowed for interactions among 17 noninvasively measured risk factors for type 2 diabetes. RESULTS: A key risk factor for type 2 diabetes was increasing age, especially for those older than 69, followed by a family history of diabetes, with diminished risk among individuals younger than 45. Above age 69, other risk factors superseded age, including systolic and diastolic blood pressure. The additive MARS model with nonlinear terms had an area under curve (AUC) receiver operating characteristic of 0.847, whereas the 2-way interaction MARS model had an AUC of 0.851, a slight improvement. Both models had an 87% accuracy in classifying diabetes status. CONCLUSION: Statistical models of type 2 diabetes risk should allow for nonlinear associations; incorporation of interaction terms into the MARS model improved its performance slightly. Robust statistical manipulation of risk factors commonly measured noninvasively in clinical settings might provide useful estimates of type 2 diabetes risk.

Dose-response association of physical activity with HbA1c: Intensity and bout length.

OBJECTIVE: The aims of this study were to characterize the dose-response relationship between moderate-to-vigorous intensity physical activity (MVPA), and light-intensity activity with HbA1c in adults at low, moderate, and high risks of type 2 diabetes, and to compare the relationship of short (1 to 9min) versus long (10+min) bouts of MVPA with HbA1c. METHODS: Data from 2707 participants from the 2003-2006 National Health And Nutrition Examination Survey were analyzed in 2014-2015. Type 2 diabetes risk was classified into three groups based upon age (<40years; ≥40years) and BMI (<30; ≥30). The relationship between HbA1c and accelerometer-based physical activity variables was assessed using multiple regression models. RESULTS: There was a curvilinear dose-response relationship between HbA1c with total activity and MVPA in adults at moderate or high risk for type 2 diabetes: higher amounts of physical activity were associated with lower HbA1c. The association of physical activity on HbA1c was stronger at lower levels of physical activity. There was no dose-response relationship in adults at low risk for type 2 diabetes. The relationship between short bouts with HbA1c was stronger than for bouts≥10min. CONCLUSIONS: In adults at risk for type 2 diabetes, there is a dose-response relationship between physical activity and HbA1c levels such that the relationship: (1) is curvilinear; (2) is stronger when a higher percent of total activity comes from MVPA; and (3) is more potent with short bouts of MVPA. Fractionalized physical activity of at least moderate-intensity may contribute to long-term glucose control.

Ethnic disparities in objectively measured physical activity may be due to occupational activity.

OBJECTIVES: We examined whether Mexican American adults report occupations that involve higher levels of objectively assessed physical activity compared with Non-Hispanic White and Black adults, and if the differences were independent of income. METHODS: Data from the 2003-2004 National Health and Nutrition Examination Survey (NHANES; N=2707) were analyzed in 2012-2013. An existing classification scheme was used to classify self-reported occupation as sedentary, low-active, or moderately active. From NHANES accelerometer data, proportion of wear time was stratified by intensity. RESULTS: A dose-response relationship was found such that workers in more active occupations spent more time in light-intensity activity and less time engaged in sedentary activities. The findings did not suggest a compensation effect for moderate-to-vigorous intensity physical activity. Mexican American adults engaged in more activity than Non-Hispanic Black or White adults for incomes between $10,000 and $64,999. CONCLUSIONS: Mexican American adults may have higher total physical activity levels in NHANES because of occupational activity, particularly among lower income households. To the extent that light-intensity activity may provide health benefits, occupational activity may partly explain the Hispanic paradox.

Objective measurement of physical activity and sedentary behavior among US adults aged 60 years or older.

INTRODUCTION: Estimates of objectively measured physical activity among older adults differ depending on the cut points used to define intensity. Our objective was to assess 1) moderate to vigorous physical activity (MVPA), exploring differences in prevalence depending on the cut point used, and 2) sedentary behavior, among US adults aged 60 years or older. METHODS: We used the most recently available accelerometer data (2003-2004 and 2005-2006) from the National Health and Nutrition Examination Survey. The sample included 2,630 adults aged 60 or older who wore an ActiGraph accelerometer for 1 week. We defined MVPA using 4 cut points (≥500, ≥1,000, ≥1,500, and ≥2,000 counts/min) and sedentary behavior as fewer than 100 counts per minute. All estimates were weighted to reflect the US population. RESULTS: The overall average counts per minute was 216. Mean MVPA ranged from 10.8 minutes per day (based on 2,000 counts/min) to 106.8 minutes per day (based on 500 counts/min). Regardless of the cut point used, MVPA was lower with each successive age group (60-69, 70-79, and ≥80) and higher among men than women. At any cut point, MVPA was highest for Hispanics and "other" racial/ethnic groups, followed by non-Hispanic whites and non-Hispanic blacks. The average time spent in sedentary behavior was 8.5 hours per day. The amount of sedentary time was greater among participants who were aged 80 or older compared to younger groups and among men compared to women. CONCLUSION: MVPA estimates vary among adults aged 60 or older, depending on the cut point chosen, and most of their time is spent in sedentary behaviors. These considerations and the data presented suggest more research is necessary to identify the appropriate method of setting accelerometer cut points for MVPA in older adults.

Latin Dance and Working Memory: The Mediating Effects of Physical Activity Among Middle-Aged and Older Latinos.

Background: Physical activity (PA) is a promising method to improve cognition among middle-aged and older adults. Latinos are at high risk for cognitive decline and engaging in low levels of PA. Culturally relevant PA interventions for middle-aged and older Latinos are critically needed to reduce risk of cognitive decline. We examined changes in cognitive performance among middle-aged and older Latinos participating in the BAILAMOS™ dance program or a health education group and compared the mediating effects of PA between group assignment and change in cognitive domains. Methods: Our 8-month randomized controlled trial tested BAILAMOS™, a 4-month Latin dance program followed by a 4-month maintenance phase. A total of 333 older Latinos aged 55+ were randomized to either BAILAMOS™, or to a health education control group. Neuropsychological tests were administered, scores were converted to z-scores, and specific domains (i.e., executive function, episodic memory, and working memory) were derived. Self-reported PA was assessed, and we reported categories of total PA, total leisure PA, and moderate-to-vigorous PA as minutes/week. A series of ANCOVAs tested changes in cognitive domains at 4 and 8 months. A mediation analysis tested the mediating effects of each PA category between group assignment and a significant change in cognition score. Results: The ANCOVAs found significant improvement in working memory scores among participants in the dance group at month 8 [F (1,328) = 5.79, p = 0.017, d = 0.20], but not in executive functioning [F (2,328) = 0.229, p = 0.80, Cohen's d = 0.07] or episodic memory [F (2,328) = 0.241, p = 0.78, Cohen's d = 0.05]. Follow-up mediation models found that total PA mediated the relationship between group assignment and working memory, in favor of the dance group (ß = 0.027, 95% CI [0.0000, 0.0705]). Similarly, total leisure PA was found to mediate this relationship [ß = 0.035, 95% CI (0.0041, 0.0807)]. Conclusion: A 4-month Latin dance program followed by a 4-month maintenance phase improved working memory among middle-aged and older Latinos. Improvements in working memory were mediated by participation in leisure PA. Our results support the current literature that leisure time PA influences cognition and highlight the importance of culturally relevant PA modalities for Latinos. Clinical Trial Registration: [www.ClinicalTrials.gov], identifier [NCT01988233].

Changes in physical functioning in the Active Living Every Day program of the Active for Life Initiative®.

BACKGROUND: Physical activity can prevent or delay the onset of physical functional limitations in older adults. There are limited data that evidence-based physical activity interventions can be successfully translated into community programs and result in similar benefits for physical functioning. PURPOSE: The purpose of this study is to measure the effects of the Active Living Every Day program on physical functioning and physical functional limitations in a diverse sample of older adults. METHODS: As a part of the Active for Life initiative, the Council on Aging of Southwestern Ohio implemented Active Living Every Day (ALED), a group-based lifestyle behavior change program designed to increase physical activity. Performance-based physical functioning tests (30-s Chair Stand Test, eight Foot Up-and-Go Test, Chair Sit-and-Reach Test, 30-Foot Walk Test) were administered to participants at baseline and posttest. Baseline to post-program changes in physical functioning and impairment status were examined with repeated measures analysis of covariance. Interactions tested whether change over time differed according to race/ethnicity, body mass index (BMI), and baseline impairment status. RESULTS: Participants significantly increased their performance in all four physical functioning tests. The percentage of participants classified as "impaired" according to normative data significantly decreased over time. Physical functioning improved regardless of BMI, race/ethnicity, or baseline impairment status. CONCLUSIONS: ALED is an example of an evidenced-based physical activity program that can be successfully translated into community programs and result in significant and clinically meaningful improvements in performance-based measures of physical functioning.

Accelerometer-Measured Sedentary Patterns are Associated with Incident Falls in Older Women.

BACKGROUND/OBJECTIVE: Falls cause significant problems for older adults. Sedentary time is associated with lower physical function and could increase the risk for falls. DESIGN: Prospective study. SETTING: Sites across the United States. PARTICIPANTS: Older women (N = 5,545, mean age 79 years) from the Women's Health Initiative Objective Physical Activity and Cardiovascular Health study. MEASUREMENTS: Accelerometers worn at the hip for up to 1 week collected measures of daily sedentary time and the mean sedentary bout duration, a commonly used metric for sedentary accumulation patterns. For up to 13 months after accelerometer wear, women reported daily whether they had fallen on monthly calendars. RESULTS: In fully adjusted models, the incident rate ratios (95% confidence interval) for quartiles 1 (lowest), 2, 3, and 4 of sedentary time respectively were 1.0 (ref.), 1.07 (0.93-1.24), 1.07 (0.91-1.25), and 1.14 (0.96-1.35; P-trend = .65) and for mean sedentary bout duration was 1.0 (ref.), 1.05 (0.92-1.21), 1.02 (0.88-1.17), and 1.17 (1.01-1.37; P-trend = .01), respectively. Women with a history of two or more falls had stronger associations between sedentary time and falls incidence compared with women with a history of no or one fall (P for interaction = .046). CONCLUSIONS: Older women in the highest quartile of mean sedentary bout duration had a significantly increased risk of falling. Women with a history of frequent falling may be at higher risk for falling if they have high sedentary time. Interventions testing whether shortening total sedentary time and/or sedentary bouts lowers fall risk are needed to confirm these observational findings.

Racial/Ethnic differences in perceived access, environmental barriers to use, and use of community parks.

INTRODUCTION: Community parks provide places for people to be physically active. Our objective was to determine how access to, barriers to use of, and use of community parks differ by race/ethnicity. METHODS: Analyses are based on a cross-sectional national sample of adults (N = 5,157) participating in the 2006 HealthStyles mail survey. Community parks were defined as outdoor public areas within 10 miles or a 20-minute drive from where a person lives that include walking/bike paths, nature preserves, playgrounds, beaches, lakes, rivers, or similar places. RESULTS: Overall, 12% of respondents reported not having a community park. Among those with a community park, 14% reported personal safety concerns and 14% reported inadequate or poorly maintained facilities as barriers to park use. Race/ethnicity was not associated with park access; however, Hispanics and non-Hispanic blacks were more likely than non-Hispanic whites to report barriers. Among those with access to a community park, 83% reported any park use in the previous year and, of these, 67% reported an active visit. Odds of any park use did not differ significantly by race/ethnicity. Odds of an active visit were significantly lower in non-Hispanic blacks than whites (odds ratio, 0.67) but did not significantly differ between Hispanics and non-Hispanic whites. CONCLUSION: Parks are valuable community resources to all racial/ethnic groups. To promote and increase community park use, it is important to be aware that parks are used differently by different racial/ethnic groups and that barriers may differentially influence park use.

Associations Between Office Location and Adiposity in Office Workers.

OBJECTIVE: Evaluate whether having to walk longer distances to common destinations within office buildings is associated with less adiposity and greater occupational physical activity. METHODS: Distances between offices and amenities were measured for 108 office-based workers, as was body fat percentage, waist circumference, number of sedentary breaks at work, and duration and intensity of activity at work. RESULTS: Being further away from the building entrance was correlated with lower body fat percentage. Greater distance from a participant's office to the copier was associated with smaller waist circumferences. Correlations were found between distance to the bathroom and work activity, and sedentary breaks with distance to the break room and distance from the printer or copier. CONCLUSIONS: Worksites interested in improving the health of their employees should consider how building design affects occupational physical activity and health.

Education and training in physical activity research and practice.

Despite rapid growth in resources devoted to physical activity promotion, the public health capacity to address physical inactivity is insufficient. Too few public health practitioners have the necessary skills to implement and evaluate evidence-based physical activity interventions, and schools of public health typically do not have adequate course content in physical activity. This commentary discusses the types of initiatives needed to improve the education and training of physical activity practitioners and researchers to effectively address one of the 21st century's greatest health problems--an inactive lifestyle.

Occupational Physical Activity Opposes Obesity: A Cross-Sectional Modern Replication of the Morris 1953 London Busmen Study.

OBJECTIVE: Examine the importance of occupational light-intensity physical activity (PA) and short bouts of moderate-vigorous PA (LSBPA), to opposing obesity, including an approximate replication of the London busmen study comparing waist circumference of workers with high versus low levels of occupational activity. METHODS: Working adults wore an accelerometer, completed anthropometric measurements, and provided work schedules. Participants' (n = 435) activity was classified as either occupational or non-occupational minutes, and by intensity. RESULTS: Body fat percentage was inversely associated with occupational-LSBPA in participants who did not meet PA guidelines, but not in those who met guidelines. In the London busmen replication, more active workers had smaller waist circumferences than sedentary workers, controlling for non-occupational activity. CONCLUSIONS: Work-related LSBPA may be an important and under-recognized source of PA that opposes adiposity for people who do not meet PA guidelines.

Hot Deck Multiple Imputation for Handling Missing Accelerometer Data.

Missing data due to non-wear are common in accelerometer studies measuring physical activity and sedentary behavior. Accelerometer output are high-dimensional time-series data that are episodic and often highly skewed, presenting unique challenges for handling missing data. Common methods for missing accelerometry either are ad-hoc, require restrictive parametric assumptions, or do not appropriately impute bouts. This study developed a flexible hot deck multiple imputation (MI; i.e., "replacing" missing data with observed values) procedure to handle missing accelerometry. For each missing segment of accelerometry, "donor pools" contained observed segments from either the same or different participants, and 10 imputed segments were randomly drawn from the donor pool according to selection weights, where the donor pool and selection weight depended on variables associated with non-wear and/or accelerometer-based measures. A simulation study of 2,550 women compared hot deck MI to two standard methods in the field: available case (AC) analysis (i.e., analyzing all observed accelerometry with no restriction on wear time or number of days) and complete case (CC) analysis (i.e., analyzing only participants that wore the accelerometer for ≥10 hours for 4-7 days). This was repeated using accelerometry from the entire 24-hour day and daytime (10am- 8pm) only, and data were missing at random. For the entire 24-hour day, MI produced less bias and better 95% confidence interval (CI) coverage than AC and CC. For the daytime only, MI produced less bias and better 95% CI coverage than AC; CC produced similar bias and 95% CI coverage, but longer 95% CIs than MI.

Sedentary Behavior and Prevalent Diabetes in 6,166 Older Women: The Objective Physical Activity and Cardiovascular Health Study.

BACKGROUND: We examined associations of sedentary time and sedentary accumulation patterns (ie, how sedentary time is accumulated) with prevalent diabetes in an ethnically diverse cohort of older women. METHODS: Community-dwelling women aged 63-99 (n = 6,116; median age = 79) wore ActiGraph GT3X+ accelerometers 24 h/day for up to 7 days from which we derived average daily sedentary time and three measures of sedentary accumulation patterns: breaks in sedentary time, usual sedentary bout duration, and alpha. Odds ratios (ORs) and 95% confidence intervals (CIs) for prevalent diabetes were estimated using multivariable logistic regression. RESULTS: Twenty-one percent (n = 1,282) of participants had diabetes. Women in the highest quartile of sedentary time (≥10.3 h/day) had higher odds of diabetes (OR = 2.18; 95% CI = 1.77-2.70) than women in the lowest quartile (≤8.3 h/day). Prolonged accumulation patterns (ie, accumulating sedentary time in longer sedentary bouts) was associated with higher odds of diabetes than regularly interrupted patterns (comparing quartiles with the most vs least prolonged patterns: usual bout duration OR = 1.57, 95% CI = 1.28-1.92; alpha OR = 1.61, 95% CI = 1.32-1.97); however, there was no significant association for breaks in sedentary time (OR = 1.00, 95% CI = 0.82-1.20). CONCLUSIONS: High levels of sedentary time and accumulating it in prolonged patterns were associated with increased odds of diabetes among older women.

Physical Activity, Injurious Falls, and Physical Function in Aging: An Umbrella Review.

PURPOSE: To review and update the evidence of the relationship between physical activity, risk of fall-related injury, and physical function in community-dwelling older people that was presented in the 2018 Physical Activity Guidelines Advisory Committee Scientific Report (PAGAC Report). METHODS: Duplicate independent screenings of 1415 systematic reviews and meta-analyses published between 2006 and 2016 identified from PubMed®, Cochrane Library, and CINAHL databases yielded 111 articles used for the PAGAC Report. The PAGAC Aging Subcommittee members graded scientific evidence strength based upon a five-criteria rubric and assigned one of four grades: strong, moderate, limited, or not assignable. An updated search of 368 articles published between January 2017 and March 2018 yielded 35 additional pertinent articles. RESULTS: Strong evidence demonstrated that physical activity reduced the risk of fall-related injuries by 32% to 40%, including severe falls requiring medical care or hospitalization. Strong evidence also supported that physical activity improved physical function and reduced the risk of age-related loss of physical function in an inverse graded manner among the general aging population, and improved physical function in older people with frailty and with Parkinson's disease. Aerobic, muscle-strengthening, and/or multicomponent physical activity programs elicited the largest improvements in physical function in these same populations. Moderate evidence indicated that for older adults who sustained a hip fracture or stroke, extended exercise programs and mobility-oriented physical activity improved physical function. CONCLUSIONS: Regular physical activity effectively helps older adults improve or delay the loss of physical function and mobility while reducing the risk of fall-related injuries. These important public health benefits underscore the importance of physical activity among older adults, especially those living with declining physical function and chronic health conditions.

The 24-Hour Activity Cycle: A New Paradigm for Physical Activity.

The physiologic mechanisms by which the four activities of sleep, sedentary behavior, light-intensity physical activity, and moderate-to-vigorous physical activity (MVPA) affect health are related, but these relationships have not been well explored in adults. Research studies have commonly evaluated how time spent in one activity affects health. Because one can only increase time in one activity by decreasing time in another, such studies cannot determine the extent that a health benefit is due to one activity versus due to reallocating time among the other activities. For example, interventions to improve sleep possibly also increase time spent in MVPA. If so, the overall effect of such interventions on risk of premature mortality is due to both more MVPA and better sleep. Further, the potential for interaction between activities to affect health outcomes is largely unexplored. For example, is there a threshold of MVPA minutes per day, above which adverse health effects of sedentary behavior are eliminated? This article considers the 24-h Activity Cycle (24-HAC) model as a paradigm for exploring inter-relatedness of health effects of the four activities. It discusses how to measure time spent in each of the four activities, as well as the analytical and statistical challenges in analyzing data based on the model, including the inevitable challenge of confounding among activities. The potential usefulness of this model is described by reviewing selected research findings that aided in the creation of the model and discussing future applications of the 24-HAC model.

Association of Light Physical Activity Measured by Accelerometry and Incidence of Coronary Heart Disease and Cardiovascular Disease in Older Women.

Importance: To our knowledge, no studies have examined light physical activity (PA) measured by accelerometry and heart disease in older women. Objective: To investigate whether higher levels of light PA were associated with reduced risks of coronary heart disease (CHD) or cardiovascular disease (CVD) in older women. Design, Setting, and Participants: Prospective cohort study of older women from baseline (March 2012 to April 2014) through February 28, 2017, for up to 4.91 years. The setting was community-dwelling participants from the Women's Health Initiative. Participants were ambulatory women with no history of myocardial infarction or stroke. Exposures: Data from accelerometers worn for a requested 7 days were used to measure light PA. Main Outcomes and Measures: Cox proportional hazards regression models estimated hazard ratios (HRs) and 95% CIs for physician-adjudicated CHD and CVD events across light PA quartiles adjusting for possible confounders. Light PA was also analyzed as a continuous variable with and without adjustment for moderate to vigorous PA (MVPA). Results: Among 5861 women (mean [SD] age, 78.5 [6.7] years), 143 CHD events and 570 CVD events were observed. The HRs for CHD in the highest vs lowest quartiles of light PA were 0.42 (95% CI, 0.25-0.70; P for trend <.001) adjusted for age and race/ethnicity and 0.58 (95% CI, 0.34-0.99; P for trend = .004) after additional adjustment for education, current smoking, alcohol consumption, physical functioning, comorbidity, and self-rated health. Corresponding HRs for CVD in the highest vs lowest quartiles of light PA were 0.63 (95% CI, 0.49-0.81; P for trend <.001) and 0.78 (95% CI, 0.60-1.00; P for trend = .004). The HRs for a 1-hour/day increment in light PA after additional adjustment for MVPA were 0.86 (95% CI, 0.73-1.00; P for trend = .05) for CHD and 0.92 (95% CI, 0.85-0.99; P for trend = .03) for CVD. Conclusions and Relevance: The present findings support the conclusion that all movement counts for the prevention of CHD and CVD in older women. Large, pragmatic randomized trials are needed to test whether increasing light PA among older women reduces cardiovascular risk.

Physical Activity to Prevent and Treat Hypertension: A Systematic Review.

PURPOSE: This systematic umbrella review examines and updates the evidence on the relationship between physical activity (PA) and blood pressure (BP) presented in the 2008 Physical Activity Guidelines Advisory Committee Scientific Report. METHODS: We performed a systematic review to identify systematic reviews and meta-analyses involving adults with normal BP, prehypertension, and hypertension published from 2006 to February 2018. RESULTS: In total, 17 meta-analyses and one systematic review with 594,129 adults ≥18 yr qualified. Strong evidence demonstrates: 1) an inverse dose-response relationship between PA and incident hypertension among adults with normal BP; 2) PA reduces the risk of cardiovascular disease (CVD) progression among adults with hypertension; 3) PA reduces BP among adults with normal BP, prehypertension, and hypertension; and 4) the magnitude of the BP response to PA varies by resting BP, with greater benefits among adults with prehypertension than normal BP. Moderate evidence indicates the relationship between resting BP and the magnitude of benefit does not vary by PA type among adults with normal BP, prehypertension, and hypertension. Limited evidence suggests the magnitude of the BP response to PA varies by resting BP among adults with hypertension. Insufficient evidence is available to determine if factors such as sex, age, race/ethnicity, socioeconomic status, and weight status or the frequency, intensity, time, and duration of PA influence the associations between PA and BP. CONCLUSIONS: Future research is needed that adheres to standard BP measurement protocols and classification schemes to better understand the influence of PA on the risk of comorbid conditions, health-related quality of life, and CVD progression and mortality; the interactive effects between PA and antihypertensive medication use; and the immediate BP-lowering benefits of PA.