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Older adults have low rates meeting the physical activity (PA) guidelines and high sedentary time. Low PA and excessive sedentary time have been linked to adverse health outcomes. Less is known about whether exercise training influences sedentary time and PA in various intensities., Purpose: This study aimed to examine the effects of a 16-wk aerobic exercise training on time spent being sedentary and on light-intensity PA (LPA) and moderate- to vigorous-intensity PA (MVPA) and step numbers in older women., Methods: Inactive women (n = 61; age = 65.5 ± 4.3 yr) participated in moderate-intensity walking of either a low or a moderate dose (33.6 and 58.8 kJ·kg body weight per week, respectively). They wore a SenseWear Mini Armband at baseline and at end intervention to determine sedentary, LPA, and MVPA time and step numbers., Results: Time being sedentary, or spent on LPA and MVPA, did not change differently by exercise groups with different doses (all P values for group-time interaction >0.580). Overall, time being sedentary reduced from baseline to end intervention by approximately 39 min·d (P < 0.001), and LPA increased by 19 min·d (P = 0.003). MVPA time increased (P < 0.001), which was primarily accounted for by the supervised exercise. Interestingly, daily steps increased more in the moderate-dose than the low-dose group (P = 0.023 for group-time interaction; 33.6% and 19.8% median increase in moderate- and low-dose groups, respectively). Also, there were individual differences in these changes., Conclusion: Results indicated that, on average, older women did not reduce time of LPA or MVPA outside the exercise program or increase sedentary time as a result of participating in the exercise program.

Purpose: Resistance exercise (RE) can improve many cardiovascular disease (CVD) risk factors, but specific data on the effects on CVD events and mortality are lacking. We investigated the associations of RE with CVD and all-cause mortality and further examined the mediation effect of body mass index (BMI) between RE and CVD outcomes., Methods: We included 12,591 participants (mean age, 47 yr) who received at least two clinical examinations 1987-2006. RE was assessed by a self-reported medical history questionnaire., Results: During a mean follow-up of 5.4 and 10.5 yr, 205 total CVD events (morbidity and mortality combined) and 276 all-cause deaths occurred, respectively. Compared with no RE, weekly RE frequencies of one, two, three times or total amount of 1-59 min were associated with approximately 40%-70% decreased risk of total CVD events, independent of aerobic exercise (AE) (all P values <0.05). However, there was no significant risk reduction for higher weekly RE of more than four times or ≥60 min. Similar results were observed for CVD morbidity and all-cause mortality. In the stratified analyses by AE, weekly RE of one time or 1-59 min was associated with lower risks of total CVD events and CVD morbidity regardless of meeting the AE guidelines. Our mediation analysis showed that RE was associated with the risk of total CVD events in two ways: RE had a direct U-shaped association with CVD risk (P value for quadratic trend <0.001) and RE indirectly lowered CVD risk by decreasing BMI., Conclusion: Even one time or less than 1 h·wk of RE, independent of AE, is associated with reduced risks of CVD and all-cause mortality. BMI mediates the association of RE with total CVD events.

Purpose: This study aimed to examine the associations of physical activity and cardiorespiratory fitness (hereafter fitness) with incident glaucoma in a prospective observational study., Methods: Physical activity was measured by self-reported leisure-time activities, and fitness was measured by maximal treadmill test. Incident glaucoma was defined based on physician diagnosis. Participants were 9519 men and women between the ages of 40 and 81 yr old (mean age 50 yr) who were enrolled in the Aerobics Center Longitudinal Study. Hazard ratios (HR) were estimated using Cox proportional hazard regression after adjusting for age, sex, race, examination year, smoking status, heavy alcohol drinking, hypertension, hypercholesterolemia, abnormal ECG, diabetes, cardiovascular disease, and cancer., Results: A total of 128 cases of incident glaucoma were reported during a mean follow-up of 5.7 yr. A significantly lower risk of incident glaucoma (HR = 0.53, 95% confidence interval [95% CI] = 0.35-0.79) was found in individuals who met the physical activity guidelines of ≥500 MET·min·wk compared with inactive individuals (0 MET·min·wk). Compared with low fitness (lower third), individuals with high fitness (upper third) also had a significantly lower risk of incident glaucoma (HR = 0.60, 95% CI = 0.38-0.95). A joint analysis of physical activity and fitness showed that meeting physical activity guidelines and being in the high fitness category was associated with the lowest risk for developing glaucoma (HR = 0.49, 95% CI = 0.31-0.79)., Conclusion: These data provide epidemiological evidence that meeting physical activity guidelines or being fit reduces the risk of developing glaucoma.

Purpose: Although the benefit of high cardiorespiratory fitness (CRF) for the prevention of type 2 diabetes mellitus (T2DM) is widely accepted, whether consistently high CRF is necessary or transiently high CRF is sufficient is unclear. The present study was conducted to examine the hypothesis that consistently high level of CRF is more beneficial than transiently high CRF for the prevention of T2DM., Methods: This cohort study was conducted in nondiabetic 7158 men age 20 to 60 yr, enrolled from 1986 to 1987. The area under the curve with respect to ground (AUCG) for CRF measurements during an 8-yr measurement period (1979-1987) was calculated as an index of integrated CRF level during the period. The differences (ΔAUCP) between AUCG and peak AUC (peak CRF-measurement period) was also calculated as an index of the presence and the size of a "spike" in CRF. T2DM was defined by fasting blood glucose and a self-reported diagnosis of diabetes for participants with blood tests. For participants without blood tests, T2DM was defined by the result of oral glucose test after a nonfasting urinary test and a self-reported diagnosis of diabetes. T2DM was determined on health checkups until 2009., Results: During the follow-up period, 1495 men developed T2DM. After adjustment for confounders, as compared with the first quartile of AUCG for CRF, the hazard ratio (95% confidence interval) for the second, third, and fourth quartiles were 0.87 (0.76 to 1.00), 0.80 (0.68 to 0.95), and 0.72 (0.58 to 0.89), respectively. For CRF spike, there was no association between ΔAUCP in CRF and the incidence of T2DM., Conclusions: Consistently higher level of CRF over time was associated with lower risk of T2DM.

Introduction: Physical activity (PA) conveys known cardiometabolic benefits to youth, but the contribution of vigorous-intensity PA (VPA) to these benefits is unknown. Therefore, we sought to determine (a) the associations between VPA and cardiometabolic biomarkers independent of moderate-intensity PA (MPA) and time sedentary and (b) the accelerometer cut point that best represents the threshold for health-promoting VPA in youth., Methods: Data from the International Children's Accelerometry Database (ICAD) were analyzed in 2015. The relationship between cardiometabolic biomarkers and four categories of VPA estimated via three sets of cut points were examined using isotemporal substitution quantile regression modeling at the 10th, 25th, 50th, 75th, and 90th percentile of the distribution of each biomarker, separately. Age, sex, accelerometer wear time, sedentary time, and MPA were controlled for while allowing substitution for light-intensity PA. Data from 11,588 youth (4-18 yr) from 11 ICAD studies (collected 1998-2009) were analyzed., Results: Only 32 of 360 significant associations were observed. Significant, negative relationships were observed for VPA with waist circumference and insulin. Replacing light-intensity PA with VPA (corresponding to at the 25th to 90th percentiles of VPA) was associated with 0.67 (-1.33 to -0.01; P = 0.048) to 7.30 cm (-11.01 to -3.58; P < 0.001) lower waist circumference using Evenson and ICAD cut points (i.e., higher counts per minute). VPA levels were associated with 12.60 (-21.28 to -3.92; P = 0.004) to 27.03 pmol·L (-45.03 to -9.03; P = 0.003) lower insulin levels at the 75th to 90th percentiles using Evenson and ICAD cut points when substituted for light PA., Conclusions: Substituting light PA with VPA was inversely associated with waist circumference and insulin. However, VPA was inconsistently related to the remaining biomarkers after controlling for time sedentary and MPA.

Purpose: Emerging evidence suggests physical activity (PA) is associated with cognitive function. To overcome limitations of self-report PA measures, this study investigated the association of accelerometer-measured PA with incident cognitive impairment and longitudinal cognition among older adults., Methods: Participants were recruited from the cohort study Reasons for Geographic and Racial Differences in Stroke in the United States. Accelerometers provided PA measures, including the percentage of total accelerometer wearing time spent in moderate-to-vigorous-intensity PA (MVPA%), light-intensity PA, and sedentary time for four to seven consecutive days at baseline. Cognitive impairment was defined by the Six-Item Screener. Letter fluency, animal fluency, word list learning, and Montreal Cognitive Assessment (orientation and recall) were conducted to assess executive function and memory., Results: Participants (N = 6452, 69.7 ± 8.5 yr, 55.3% women, 30.5% Black) with usable accelerometer and cognition measures spent extremely limited time in MVPA (1.5% ± 1.9% of accelerometer wearing time). During an average of 3 yr of follow-up, 346 cases of incident cognitive impairment were observed. After adjustments, participants in higher MVPA% quartiles had a lower risk of cognitive impairment (i.e., quartile 2: odds ratio = 0.64, 95% confidence interval = 0.48-0.84) and better maintenance in executive function (≥0.03 z-score units) and memory (≥0.12 z-score units) compared with quartile 1 (P < 0.05). Stratified analyses showed the same association among White adults, but higher MVPA% was associated with better maintenance of only memory among Black adults. No significance was found for light-intensity PA or sedentary time., Conclusion: There was a dose-response relationship between MVPA% and cognitive function in older adults, with higher levels associated with a 36% or lower risk of cognitive impairment and better maintenance of memory and executive function over time, particularly in White adults., Competing Interests: and Source of Funding: None. The results of the present study do not constitute endorsement by ACSM. The results of the study are presented clearly, honestly, and without fabrication, falsification, or inappropriate data manipulation.

Purpose: The purposes of this study were to examine patterns of objectively measured sedentary behavior in a national cohort of US middle-age and older adults and to determine factors that influence prolonged sedentary behavior., Methods: We studied 8096 participants from the REasons for Geographic and Racial Differences in Stroke (REGARDS) Study, a population-based study of black and white adults 45 yr or older. Seven-day accelerometry was conducted. Prolonged sedentary behavior was defined as accumulating 50% or more of total sedentary time in bouts of 30 min or greater., Results: The number of sedentary bouts greater than or equal to 20, 30, 60, and 90 min were 8.8 ± 2.3, 5.5 ± 1.9, 1.9 ± 1.1, and 0.8 ± 0.7 bouts per day, respectively. Sedentary bouts greater than or equal to 20, 30, 60, and 90 min accounted for 60.0% ± 13.9%, 48.0% ± 15.5%, 26.0% ± 15.4%, and 14.2% ± 12.9% of total sedentary time, respectively. Several factors were associated with prolonged sedentary behavior in multivariate-adjusted models (odds ratio [95% confidence interval]): older age (65-74 yr: 1.99 [1.55-2.57]; 75 yr or older: 4.68 [3.61-6.07] vs 45-54 yr), male sex (1.41 [1.28-1.56] vs female), residence in nonstroke belt/buckle region of the United States (stroke belt: 0.87 [0.77-0.98]; stroke buckle: 0.86 [0.77-0.95] vs non-belt/buckle), body mass index (BMI) (overweight: 1.33 [1.18-1.51]; obese: 2.15 [1.89-2.44] vs normal weight), winter (1.18 [1.03-1.35] vs summer), and low amounts of moderate-to-vigorous physical activity (MVPA) [0 min·wk: 2.00 [1.66-2.40] vs ≥150 min·wk)., Conclusions: In this sample of US middle-age and older adults, a large proportion of total sedentary time was accumulated in prolonged, uninterrupted bouts of sedentary behavior as almost one-half was accumulated in sedentary bouts greater than or equal to 30 min. Several sociodemographic (age, sex, and BMI), behavioral (MVPA), environmental (region), and seasonal factors are associated with patterns of prolonged sedentary behavior.

Purpose: Despite the widely accepted benefits of exercise on chronic disease risk, controversy remains on the role of exercise in weight loss. This study examined the effect of different exercise types on measures of adiposity across different fat categories., Methods: A total of 348 young adults (49% male; 28 ± 4 yr), participating in an ongoing observational study provided valid data over a period of 12 months. Fat mass (FM) and lean mass (LM) were measured via dual x-ray absorptiometry every 3 months. Percent body fat was calculated and used to differentiate between normal-fat, "overfat," and obese participants. At each measurement time point, participants reported engagement (min·wk) in aerobic exercise, resistance exercise, and other forms of exercise., Results: Most participants (93%) reported some exercise participation during the observation period. Total exercise or specific exercise types did not significantly affect subsequent body mass index after adjusting for sex, ethnicity, age, and baseline values of adiposity and exercise. Resistance exercise affected LM (P < 0.01) and FM (P < 0.01), whereas aerobic exercise only affected FM (P < 0.01). Any exercise type positively affected LM in normal-fat participants (P < 0.04). In overfat and obese participants, FM was reduced with increasing resistance exercise (P ≤ 0.02) but not with aerobic exercise (P ≥ 0.09). Additionally adjusting for objectively assessed total physical activity level did not change these results., Conclusions: Despite the limited effects on body mass index, exercise was associated with beneficial changes in body composition. Exercise increased LM in normal-fat participants and reduced FM in overfat and obese adults. Adults with excess body fat may benefit particularly from resistance exercise.

Purpose: This study aimed to describe the scope of accelerometry data collected internationally in adults and to obtain a consensus from measurement experts regarding the optimal strategies to harmonize international accelerometry data., Methods: In March 2014, a comprehensive review was undertaken to identify studies that collected accelerometry data in adults (sample size, n ≥ 400). In addition, 20 physical activity experts were invited to participate in a two-phase Delphi process to obtain consensus on the following: unique research opportunities available with such data, additional data required to address these opportunities, strategies for enabling comparisons between studies/countries, requirements for implementing/progressing such strategies, and value of a global repository of accelerometry data., Results: The review identified accelerometry data from more than 275,000 adults from 76 studies across 36 countries. Consensus was achieved after two rounds of the Delphi process; 18 experts participated in one or both rounds. The key opportunities highlighted were the ability for cross-country/cross-population comparisons and the analytic options available with the larger heterogeneity and greater statistical power. Basic sociodemographic and anthropometric data were considered a prerequisite for this. Disclosure of monitor specifications and protocols for data collection and processing were deemed essential to enable comparison and data harmonization. There was strong consensus that standardization of data collection, processing, and analytical procedures was needed. To implement these strategies, communication and consensus among researchers, development of an online infrastructure, and methodological comparison work were required. There was consensus that a global accelerometry data repository would be beneficial and worthwhile., Conclusions: This foundational resource can lead to implementation of key priority areas and identification of future directions in physical activity epidemiology, population monitoring, and burden of disease estimates.

Purpose: Comparative effectiveness research (CER) is designed to support informed decision making at both the individual, population, and policy levels. The American College of Sports Medicine and partners convened a conference with the focus of building an agenda for CER within the context of physical activity and nonpharmacological lifestyle approaches in the prevention and treatment of chronic disease. This report summarizes the conference content and consensus recommendations that culminated in a CER roadmap for physical activity and lifestyle approaches to reducing the risk of chronic disease., Methods: This conference focused on presentations and discussion around the following topic areas: 1) defining CER, 2) identifying the current funding climate to support CER, 3) summarizing methods for conducting CER, and 4) identifying CER opportunities for physical activity., Results: This conference resulted in consensus recommendations to adopt a CER roadmap for physical activity and lifestyle approaches to reducing the risk of chronic disease. In general, this roadmap provides a systematic framework by which CER for physical activity can move from a planning phase to a phase of engagement in CER related to lifestyle factors with particular emphasis on physical activity to a societal change phase that results in changes in policy, practice, and health., Conclusions: It is recommended that physical activity researchers and health care providers use the roadmap developed from this conference as a method to systematically engage in and apply CER to the promotion of physical activity as a key lifestyle behavior that can be effective at making an impact on a variety of health-related outcomes.

Purpose: The objective of this study is to report methodological details and feasibility of conducting an accelerometer ancillary study in a large US cohort being followed for stroke and cognitive decline., Methods: Reasons for Geographic and Racial Differences in Stroke is a national population-based study of 30,239 blacks and whites, age ≥45 yr, enrolled January 2003 to October 2007. Baseline evaluations were conducted through computer-assisted telephone interview and an in-home visit. Participants are followed by computer-assisted telephone interview every 6 months. Starting with May 2009 follow-up, contingent on accelerometer availability, participants were invited to wear an accelerometer for 7 d. Device inventory was 1150. Accelerometer, instructions, log sheet, and stamped addressed return envelope were mailed to consenting participants. Postcard acknowledgement and reminders and two calls or less were made to encourage compliance., Results: Between May 2009 and January 2013, 20,076 were invited to participate; 12,146 (60.5%) consented. Participation rates by race-sex groups were similar: black women, 58.6%; black men, 59.6%; white women, 62.3%; and white men, 60.5%. The mean age of the 12,146 participants to whom devices were shipped was 63.5 ± 8.7 yr. Return rate was 92%. Of 11,174 returned, 1187 were not worn and 14 had device malfunction, and of 9973 with data, 8096 (81.2%) provided usable data, defined as ≥4 d of 10+ h of wear time, ranging from 74.4% among black women to 85.2% among white men., Conclusions: Using mail and telephone methods, it is feasible to obtain objective measures of physical activity from a sizeable proportion of a national cohort of adults, with similar participation rates among blacks and whites. Linked with the clinical health information collected through follow-up, these data will allow future analyses on the association between objectively measured sedentary time, physical activity, and health outcomes.