Light-intensity Activity Research Articles

Does Multiple Sclerosis Differently Impact Physical Activity in Women and Man? A Quantitative Study Based on Wearable Accelerometers.

In people with multiple sclerosis (pwMS), fatigue, weakness and spasticity may reduce mobility and promote sedentary behavior. However, little is known about the existence of possible differences in the way MS modifies the propensity to perform physical activity (PA) in men and women. The present study aimed to partly close this gap by means of quantitative analysis carried out using wearable sensors. Forty-five pwMS (23 F, 22 M, mean age 50.3) and 41 unaffected age- and sex-matched individuals wore a tri-axial accelerometer 24 h/day for 7 consecutive days. Raw data were processed to calculate average number of daily steps, vector magnitude (VM) counts, and percentage of time spent in sedentary behavior and in PA of different intensities (i.e., light and moderate-to-vigorous, MVPA). Women with MS spent more time in sedentary behavior and exhibited a reduced amount of light intensity activity with respect to men, while MVPA was similar across sexes. However, in comparison with unaffected individuals, the overall PA patterns appear significantly modified mostly in women who, in presence of the disease, present increased sedentary behavior, reduced MVPA, number of daily steps and VM counts. The findings of the present study highlight the urgency of including sex as variable in all studies on PA in pwMS.

Advancing the global physical activity agenda: recommendations for future research by the 2020 WHO physical activity and sedentary behavior guidelines development group

BackgroundIn July, 2019, the World Health Organization (WHO) commenced work to update the 2010 Global Recommendations on Physical Activity for Health and established a Guideline Development Group (GDG) comprising expert public health scientists and practitioners to inform the drafting of the 2020 Guidelines on Physical Activity and Sedentary Behavior. The overall task of the GDG was to review the scientific evidence and provide expert advice to the WHO on the amount of physical activity and sedentary behavior associated with optimal health in children and adolescents, adults, older adults (> 64 years), and also specifically in pregnant and postpartum women and people living with chronic conditions or disabilities.MethodsThe GDG reviewed the available evidence specific to each sub-population using systematic protocols and in doing so, identified a number of gaps in the existing literature. These proposed research gaps were discussed and verified by expert consensus among the entire GDG.ResultsEvidence gaps across population sub-groups included a lack of information on: 1) the precise shape of the dose-response curve between physical activity and/or sedentary behavior and several of the health outcomes studied; 2) the health benefits of light-intensity physical activity and of breaking up sedentary time with light-intensity activity; 3) differences in the health effects of different types and domains of physical activity (leisure-time; occupational; transportation; household; education) and of sedentary behavior (occupational; screen time; television viewing); and 4) the joint association between physical activity and sedentary time with health outcomes across the life course. In addition, we acknowledge the need to conduct more population-based studies in low- and middle-income countries and in people living with disabilities and/or chronic disease, and to identify how various sociodemographic factors (age, sex, race/ethnicity, socioeconomic status) modify the health effects of physical activity, in order to address global health disparities.ConclusionsAlthough the 2020 WHO Guidelines for Physical Activity and Sedentary Behavior were informed by the most up-to-date research on the health effects of physical activity and sedentary time, there is still substantial work to be done in advancing the global physical activity agenda.

Improving the criterion validity of the activPAL in determining physical activity intensity during laboratory and free-living conditions

ABSTRACT The activPAL is a valid measure of step counts and posture, but its ability to determine physical activity intensity is unclear. This study tested the criterion validity of the activPAL using its built-in linear cadence-metabolic equivalents (METs) equation (activPAL-linear) versus an individualized height-adjusted curvilinear cadence-METs equation (activPAL-curvilinear) to estimate intensity-related physical activity. Forty adults (25±6 years, 23.3±4.1 kg/m2) wore an activPAL during a 7-stage progressive treadmill walking protocol (criterion: indirect calorimetry). A sub-sample (n=32) wore the device during free-living conditions for 7-days (criterion: PiezoRxD monitor). In the laboratory, the activPAL-linear overestimated METs during slow walking (1.5–3.0 miles•hour−1) but underestimated METs during fast walking (3.5–4.5 miles•hour−1) (all, p<0.001). In the free-living condition, the activPAL-linear overestimated time in light-intensity activity and underestimated moderate-intensity activity (both, p<0.001), but did not register any vigorous-intensity activity. In contrast, the activPAL-curvilinear estimated values statistically equivalent to indirect calorimetry for treadmill stages 1–6 (1.5–4.0 miles•hour−1) and to the PiezoRxD determined light- and moderate-intensity activity during free-living. We present a simple, data processing technique that uses an alternative curvilinear cadence-MET equation that improves the ability of the activPAL to measure intensity-related physical activity in both laboratory and free-living settings.

Physical Activity Level during Pregnancy in South Africa: A Facility-Based Cross-Sectional Study.

Physical activity participation during pregnancy confers many maternal and foetal health benefits to the woman and her infant and is recommended by various health bodies and institutions. However, in South Africa, scant information exists about the physical activity status and its determinants among pregnant women. The aim of this study was to assess the physical activity level and associated factors among pregnant women. This cross-sectional study enrolled 1082 pregnant women attending public health facilities in Buffalo City Municipality, Eastern Cape, South Africa. Information on socio-demographic and maternal characteristics were obtained, and the Pregnancy Physical Activity Questionnaire was used to assess physical activity during pregnancy. Multiple logistic regression analyses were used to assess associations between physical activity and the predictor variables during pregnancy. Adjusted odds ratios with 95% confidence interval were applied to estimate factors associated with physical activity levels. Statistical significance was set at p < 0.05. Only 278 of the women (25.7%) met recommendations for prenatal activity (≥150 min moderate intensity exercise per week). The average time spent in moderate–vigorous physical activity was 151.6 min (95% CI: 147.2–156.0). Most of the women participated in light exercises with a mean of 65.9% (95% CI: 64.8–67.0), and 47.6% (95% CI: 46.3–48.9) participated in household activities. The majority of the women did not receive physical activity advice during prenatal care sessions (64.7%). Factors negatively associated with prenatal physical activity were lower age (<19 years) (adjusted odd ratio (AOR) = 0.3; CI: 0.16–0.76), semi-urban residence (AOR = 0.8; CI: 0.55–1.03), lower educational level (AOR = 0.5; CI: 0.20–0.71), unemployment (AOR = 0.5; CI: 0.29–0.77) and nulliparity (AOR = 0.6; CI: 0.28–1.31). However, prenatal physical activity was positively associated with starting physical activity in the first trimester (AOR = 1.9; CI: 1.06–3.31) compared to other trimesters. The findings of this study demonstrated low levels of physical activity during pregnancy in South Africa. The majority of women did not meet the recommendation of 150 min of moderate intensity activity per week. Light intensity and household activities were the most preferred form of activity. The factors affecting physical activity of women in this present study include lower age, semi-urban setting, low educational level, unemployment and nulliparity. In order to increase activity levels, future work should seek to improve knowledge, access and support for physical activity in pregnant women in South Africa. This should include education and advocacy regarding physical activity for professionals involved in maternal health provision.

Association between Physical Activity and Mortality in Patients with Claudication.

This study aimed to determine the association between light-intensity physical activity and the incidence of all-cause and cardiovascular mortality in patients with peripheral artery disease (PAD) limited by claudication followed for up to 18.7 yr. A total of 528 patients with PAD and claudication were screened in Baltimore between 1994 and 2002, and 386 were deemed eligible for the study. At baseline, patients were classified into three physical activity groups: 1) physically sedentary, 2) light intensity, and 3) moderate to vigorous intensity based on a questionnaire. All-cause and cardiovascular mortality of patients through December 2014 was determined using the National Death Index and the U.S. Department of Veterans Affairs and the U.S. Department of Defense Suicide Data Repository. Median survival time was 9.9 yr (interquartile range, 4.9-15.7 yr; range, 0.38-18.7 yr). During follow-up, 257 patients (66.6%) died, consisting of 40/48 (83.3%) from the sedentary group, 135/210 (64.3%) from the light-intensity group, and 82/128 (64.0%) from the moderate- to vigorous-intensity group. For all-cause mortality, light-intensity activity status (hazard ratio [HR] = 0.523, P = 0.0007) and moderate- to vigorous-intensity status (HR = 0.425, P < 0.0001) were significant predictors. During follow-up, 125 patients died because of cardiovascular causes (32.4%), in which light-intensity activity status (HR = 0.511, P = 0.0113) and moderate- to vigorous-intensity activity status (HR = 0.341, P = 0.0003) were significant predictors. Light-intensity physical activity is associated with nearly 50% lower risk of all-cause and cardiovascular mortality in high-risk patients with PAD and claudication. Furthermore, moderate- to vigorous-intensity physical activity performed regularly is associated with 58% and 66% lower risk of all-cause and cardiovascular mortality, respectively. The survival benefits associated with light-intensity physical activity make it a compelling behavioral intervention that extends beyond improving ambulation.

Describing objectively measured intensive care nurses' physical work activity behavioural patterns during a 12-hr shift.

To describe intensive care unit (ICU) nurses' physical work activity behavioural patterns over 12hr using dual accelerometry, following a job demands-recovery framework. Limited studies utilised accelerometry to objectively analyse nurses' physical workloads. Little is known about intensive care nurses' physical activity patterns during a 12-hr shift. A cross-sectional study was conducted with intensive care nurses from four units in Auckland, New Zealand. Each participant wore two Axivity AX3 accelerometers to measure physical activity during a 12-hr day or night shift. An online survey captured participants' demographic information. R software (version 3.6.1) and SPSS version 26 were utilised for data analysis. The STROBE was followed. A total of 102 nurses were included in this study. A high level of light intensity activity behaviours (standing, dynamic standing, walking) was observed throughout the day shifts, with no higher intensity behaviours identified. Activity levels were highest at the beginning of shifts and followed a consistent pattern, with an additional peak around midday for day shifts and at the end of the shift for night shifts. Observable differences were seen between day and night shifts with a greater prevalence of sitting and lying during night shifts. Standing, dynamic standing, sitting, lying and walking were significant factors in the differences of the physical work behaviours between the day shift nurses and the night shift nurses. Significant differences in dynamic standing and lying were found between ICUs. Intensive care nurses' physical work activity involved a large amount of standing and dynamic standing during a 12-hr shift. The overall physical workload during a 12-hr day shift was significantly higher than that during a 12-hr night shift. Results may help managers attain a better understanding of nurses' physical workloads during a 12-hr shift.

Abstract PR07: Device-based, objective measurement of physical activity and sedentary behavior in a large U.S. cohort

Abstract Physical activity guidelines state that adults should engage in at least 150 minutes of moderate or 75 minutes of vigorous intensity activity per week and limit time spent sitting. Guidelines are based largely on self-reported data of usual amounts of physical activity and sitting time, as self-report is a feasible and cost-effective method for assessment in large epidemiologic studies. However, self-reported survey measures largely focus on moderate-to-vigorous intensity physical activity (MVPA) and total sitting time, and they are subject to various sources of error. The American Cancer Society’s Cancer Prevention Study-3 (CPS-3) is a large, nationwide, prospective cohort of approximately 304,000 participants recruited from 2006-2013. Among 751 randomly selected CPS-3 participants, seven-day accelerometer data were collected at two-time points approximately 6 months apart in 2015/2016 to assess convergent validity of the CPS-3 physical activity survey data. The average number of wear days was excellent (6.6). Vigorous activity (r=0.75) was reported more accurately than light activity (r=0.31); sedentary time also showed reasonable validity (r=0.63). While CPS-3 and other cohort surveys have acceptable validity and are suitable for categorizing participants according to overall activity level, they do not allow for detailed examination of bouts, patterns, or intensity of different activities, especially in terms of measuring light-intensity activity where most active time is spent. Thus, some large cohorts have collected or are collecting accelerometer data on subpopulations to use for calibrating self-reported measures and for examining objective physical activity in relation to health outcomes. We are initiating collection of accelerometer data from a subcohort of at least 20,000 participants. We aim to oversample for men and racial/ethnic minorities as most previous accelerometry studies included predominantly white women. Participants will be sent an accelerometer (ActiGraph GT3x) with a brief survey/wear-time log and asked to wear the device for a maximum of seven days during all waking hours. Through a series of prediction models, the CPS-3 survey will be trained against a smaller subset of accelerometer data to improve the interpretability, accuracy, and precision of CPS-3 sedentary time and PA survey data. Associations of accelerometer-based physical activity with various outcomes will also be conducted. Through the quantifiable assessment of activity at different intensities, bout lengths, and patterns, we will be well positioned to understand dose-response of physical activity and sedentary time in relation to health and better inform public health guidelines. CPS-3 will not only add to the growing number of cohorts with device-based measures but also can uniquely contribute to gaps in the research with its younger age range, inclusion of men and women, and geographic as well as racial/ethnic diversity. This abstract is also being presented as Poster A33. Citation Format: Alpa V. Patel, Erika Rees-Punia, Susan M. Gapstur. Device-based, objective measurement of physical activity and sedentary behavior in a large U.S. cohort [abstract]. In: Proceedings of the AACR Special Conference on Modernizing Population Sciences in the Digital Age; 2019 Feb 19-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(9 Suppl):Abstract nr PR07.

University students’ knowledge, self-efficacy, outcome expectations, and barriers related to reducing sedentary behavior: a qualitative study

Objective To explore university students’ knowledge, self-efficacy, outcome expectations, barriers and ideas related to reducing sedentary behavior using a qualitative approach. Participants: Nineteen students from a Canadian university participated. Methods: Four focus groups were conducted. Discussions were recorded, transcribed, and coded to identify categories and themes. Results: Some students lacked knowledge of the concept, but most were generally aware of health risks associated with sedentary behavior. Most students were confident they could reduce sedentary behavior, but felt it would be unlikely they would actually do so because: (a) it is not a priority, (b) the health consequences are distal, (c) increasing standing and light-intensity activity would not provide meaningful health benefits, and (d) class schedules/norms/infrastructure encourage sitting and are not under their control to change. Conclusion: Findings from this study may help inform intervention strategies aimed at decreasing excessive sedentary behavior among university students.

Adiposity And Cardiovascular Health And The Reallocation Of Waking Activities In Preschool Children With Overweight

Physical activity and sedentary behaviors differentially relate to health outcomes in children. Isotemporal substitution provides opportunities to evaluate the relation of hypothetical time replacement scenarios across intensity categories with health. Few isotemporal studies have been conducted among preschool-aged youth and ethnically diverse populations. PURPOSE: To examine the relation of reallocation of waking activity behaviors on 1) adiposity and 2) cardiovascular health indicators among preschool-aged youth (ages 2-5 years) with overweight participating in Texas Childhood Obesity Research Demonstration (TX CORD), a low-income, majority Hispanic cohort. METHODS: Participants wore an ActiGraph wGT3X-BT monitor (waist) and attended health assessments. Valid wear time was defined as ≥10 hours between 06:00-22:59 hours on ≥3 days (≥1 weekend). Adiposity measures were percentage of the 95th percentile (%BMIp95), fat mass, fat mass index, waist circumference, and waist-to-hip ratio. Cardiovascular measures were resting systolic (SBP) and diastolic (DBP) blood pressure, and heart rate. Covariates included age, sex, ethnicity, and socioeconomic status. Isotemporal substitution modeling was employed to address the study purpose. RESULTS: Complete data were available for 131 children (Mean age = 4.3±1.1, 53% female, 87% Hispanic, 31% ≤49% income to poverty ratio). For boys, reallocating 15 minutes of sedentary, light, or moderate intensity activity to vigorous intensity activity was significantly associated with beneficial reductions in all adiposity indicators; for girls, these relations were statistically null. For boys and girls, reallocating 15 minutes of sedentary (-5.0 SBP, -3.7 DBP), light (-4.3 SBP, -3.2 DBP), or moderate intensity activity (-7.3 SBP, -5.5 DBP) to vigorous intensity activity was significantly associated with favorable cardiovascular indicators. CONCLUSIONS: Substituting vigorous for lower intensity physical activity is associated with several favorable adiposity and cardiovascular health outcomes among preschool children with overweight and obesity. Teaching caregivers how to engage young children in vigorous intensity is needed, especially as overweight children spend more time sedentary and less time in higher intensity activities.

Exercise Is Medicine On Campus: Employee Circuit Training Course Increases Physical Activity

PURPOSE: Exercise Is Medicine On Campus (EIM-OC) is a global health initiative with over 200 participating college campuses. EIM-OC was implemented at California State University, Monterey Bay in Fall 2019, with offerings for both students and employees. Employee programming included exercise classes, including a four week circuit training course. The purpose of this pilot study was to evaluate physical activity participation among employees participating in the EIM-OC circuit training course. METHODS: The research design was pre-post and tracked participants in the EIM-OC circuit training course. Twelve female employees who were participating in the class volunteered for the study. The Godin Leisure Time Physical Activity Questionnaire was administered online before and after the course. Paired sample t-tests were performed on Godin Scale Score, and number of strenuous, moderate, and light intensity activity days per week. Significance was set at α; = 0.05. RESULTS: There was a significant increase (t=-1.787, df=11, p=.05) in Godin Scale Score following the course (M=38.50±16.9; M=49.17±23.95). There was a significant increase in moderate physical activity days per week (t=-2.419, df=11, p=.02) following the course (M=2.5±1.17; M=3.33±1.30). There were increases in strenuous physical activity days and light physical activity days per week, although they were not statistically significant. CONCLUSIONS: The inaugural EIM-OC circuit training class was effective in increasing physical activity among female employees. Future EIM-OC programs should work to expand their offerings to increase participation among employees, especially those who are inactive. Larger and longer studies could also be helpful to the growing body of knowledge on the EIM-OC initiative.

Relationship Between Physical Activity Intensity And Bone Mineral Density In Premenopausal Women

Osteoporosis has become a global health problem. Mechanical loading during physical activity (PA) and exercise increases and maintains bone mass and strength. Quantitative PA measures are needed to identify the functional loading intensity that is beneficial for bone health. PURPOSE: This study aimed to examine the relationship between PA intensity and bone mineral density (BMD) at the femur and spine in premenopausal women. METHODS: The data from 2005–2006 National Health and Nutrition Examination Survey (NHANES) were used for this study. PA was assessed using ActiGraph accelerometers, and bone health metrics were measured through dual-energy X-ray absorptiometry. After removing all missing values, 1446 female participants (Age: 47.61 ± 5.39 yr., Height: 162.01 ± 6.30 cm, Weight: 74.60 ±16.80 kg, BMI: 28.45 ± 6.30 kg/m2) remained. PA intensity is translated from accelerometer counts per minute (cnts/min) using the thresholds in previous calibration studies, e.g.: Light intensity activity = 100–1951 cnts/min, Moderate–vigorous intensity = 1952–5724 cnts/min, and Vigorous intensity > 5724 cnts/min. The bone health metrics were the BMD of femur neck, trochanter, total femur, and total spine. The correlations between PA intensity with bone health metrics were computed. RESULTS: The means and standard deviations of Light intensity = 537.79 ± 85.59 (cnts/min), Moderate-vigorous intensity = 2694.48 ± 340.54 (cnts/min), and Vigorous intensity = 7120.53 ± 1721.06 (cnts/min). A low correlation between overall PA intensity and total BMD (r = 0.01) was found. Correlations between different PA intensities and BMD are summarized below:CONCLUSION: Although low correlation was found between PA intensity and BMD, only no or low correlation was found between BMD and a specific PA intensity. Lack of variabilities within a specific PA intensity may be the reason. More studies are needed to understand the relationship between PA intensity and bone health.

Physiological Demands Of Snowboarding: A Field Study

PURPOSE: Snowboarding is a recreational activity with large popularity and is also a sport in the Winter Olympics. Despite its popularity and inclusion in the Olympic program, relatively little remains known about the physiological characteristics of a snowboard session, particularly in field settings. The purpose of this study was to classify physiological responses to recreational snowboarding relative to ACSM daily activity guidelines. METHODS: To date, twenty-one men and women who were experienced snowboarders were recruited from a university community and while snowboarding wore a heart-rate monitor and GPS device. Data were collected at 1-second intervals and analyzed for time spent in moderate and vigorous intensities based on percentage of heart rate maximum (HRMAX) (light ≤ 64% HRMAX; moderate 64–76% HRMAX; vigorous ≥76% HRMAX). Based on this information, the amount of time in each HRZONE was calculated. Data were processed and analyzed using R and SPSS. RESULTS: Participants snowboarded an average duration of ~6 hours, covering ~38 kilometers. Average heart rate over the entire session was 63.3±9.5% of HRMAX (122±19 BPM); during actual snowboarding, average heart rates were ~72% of HRMAX (140±10 BPM). Participants spent a significantly greater amount of time in light and moderate intensity activity during non-snowboarding activity (NS) compared to snowboarding (SN) (p < 0.001 for both),but amount of time in vigorous intensity was not different between conditions (NS: 31.05 ± 35.78 vs SN: 39.36 ± 33.67 minutes, p = 0.478). Total MVPA during SN was 62.33 ± 32.90 minutes compared to 82.86 ± 68.41 minutes for NS, which was not significantly different (p = 0.262). CONCLUSION: The present data suggest that snowboarding can meet ACSM guidelines for moderate-vigorous intensity exercise of at least 30 minutes a day.

Preschoolers exhibit greater on-task behavior following physically active lessons on the approximate number system.

To determine how the dual-task nature of incorporating physical activity with instructional activities immediately impacts acuity of the approximate number system and on-task behavior in preschoolers. Using a randomized within-participants repeated-measures crossover design, 51 children completed an approximate number system task before and after either 20-min of physically active instruction corresponding to 38% heart rate reserve (HRR; light-to-moderate intensity) or conventional sedentary instruction at corresponding to 21% HRR (very light intensity). Findings revealed that preschool-aged children exhibited similar learning and greater on-task behavior following a single bout of physically active instruction relative to conventional sedentary instruction. Overall, preschoolers accrued 931.3±8.2 more steps and an additional 9minutes at or above light-intensity activity during the physically active instruction. Accordingly, these findings suggest that the dual-task nature of physically active learning does not compromise learning, reduces the need for redirecting off-task behavior, and ultimately allows children to avoid sedentary behavior in educational contexts.

Osteoarthritis physical activity care pathway (OA-PCP): results of a feasibility trial

BackgroundTo obtain information on feasibility and acceptability, as well as preliminary data on efficacy, of an Osteoarthritis Physical activity Care Pathway (OA-PCP).MethodsThis was a single group pilot study involving 60 participants with symptomatic, physician diagnosed knee or hip OA, recruited from primary care clinics. Participants self-reported completing less than 150 min per week of moderate-to-vigorous physical activity (MVPA) at baseline. The 3-month OA-PCP intervention involved 3 physical activity (PA) coaching calls (focused on goal setting), three check-in emails and linkage with community-based or online resources to support PA. Efficacy outcomes were collected at baseline and 4-month follow-up. The primary efficacy outcome was minutes of MVPA, assessed via accelerometer. Secondary outcomes included minutes of light intensity activity, sedentary minutes, step counts, and Western Ontario and McMaster Universities (WOMAC) pain and function subscales. Participants were also asked to rate the helpfulness of the OA-PCP intervention on a scale of 0–10. Differences in efficacy outcomes between baseline and 4-month follow-up were assessed using paired t-tests.ResultsAmong participants beginning the study, 88% completed follow-up assessments and ≥ 90% completed each of the intervention calls. Average daily minutes of MVPA was 8.0 at baseline (standard deviation (SD) = 9.9) and 8.9 at follow-up (SD = 12.1, p = 0.515). There were no statistically significant changes in light intensity activity, sedentary time or step counts. The mean WOMAC pain score improved from 8.1 (SD = 3.6) at baseline to 6.2 (SD = 3.8) at follow-up (p < 0.001); the mean WOMAC function score improved from 26.2 (SD = 13.2) to 20.2 (SD = 12.5; p < 0.001). The mean rating of helpfulness was 7.6 (SD = 2.5).ConclusionsResults supported the feasibility and acceptability of the study, and participants reported clinically relevant improvements in pain and function. PA metrics did not improve substantially. Based on these results and participant feedback, modifications including enhanced self-monitoring are being made to increase the impact of the OA-PCP intervention on PA behavior.Trial registrationNCT03780400, December 19, 2018.

The relationship between living in urban and rural areas of Scotland and children\u2019s physical activity and sedentary levels: a country-wide cross-sectional analysis

BackgroundLiving in urban or rural environments may influence children’s levels of physical activity and sedentary behaviours. We know little about variations in device-measured physical activity and sedentary levels of urban and rural children using nationally representative samples, or if these differences are moderated by socioeconomic factors or seasonal variation. Moreover, little is known about the influence of ‘walkability’ in the UK context. A greater understanding of these can better inform intervention strategies or policy initiatives at the population level.MethodsCountry-wide cross-sectional study in Scotland in which 774 children (427 girls, 357 boys), aged 10/11 years, wore an accelerometer on one occasion for at least four weekdays and one weekend day. Mean total physical activity, time spent in sedentary, light, and moderate-to-vigorous physical activity (MVPA), per day were extracted for weekdays, weekend days, and all days combined. Regression analyses explored associations between physical activity outcomes, urban/rural residence, and a modified walkability index (dwelling density and intersection density); with interactions fitted for household equivalised income and season of data collection. Sensitivity analyses assessed variation in findings by socioeconomic factors and urbanicity.ResultsRural children spent an average of 14 min less sedentary (95% CI of difference: 2.23, 26.32) and 13 min more in light intensity activity (95% CI of difference, 2.81, 24.09) per day than those from urban settlements. No urban-rural differences were found for time spent in MVPA or in total levels of activity. Our walkability index was not associated with any outcome measure. We found no interactions with household equivalised income, but there were urban/rural differences in seasonal variation; urban children engaged in higher levels of MVPA in the spring months (difference: 10 mins, p = 0.06, n.s) and significantly lower levels in winter (difference: 8.7 mins, p = 0.036).ConclusionsExtrapolated across one-year, rural children would accumulate approximately 79 h (or just over 3 days) less sedentary time than urban children, replacing this for light intensity activity. With both outcomes having known implications for health, this finding is particularly important. Future work should prioritise exploring the patterns and context in which these differences occur to allow for more targeted intervention/policy strategies.

A randomized controlled trial to reduce sedentary time in rheumatoid arthritis: protocol and rationale of the Take a STAND for Health study

BackgroundPatients with rheumatoid arthritis spend most of their daily hours in sedentary behavior (sitting), a predisposing factor to poor health-related outcomes and all-cause mortality. Interventions focused on reducing sedentary time could be of novel therapeutic relevance. However, studies addressing this topic remain scarce. We aim to investigate the feasibility and efficacy of a newly developed intervention focused on reducing sedentary time, and potential clinical, physiological, metabolic and molecular effects in rheumatoid arthritis.MethodsThe Take a STAND for Health study is a 4-month, parallel-group, randomized controlled trial, in which postmenopausal patients with rheumatoid arthritis will set individually tailored, progressive goals to replace their sedentary time with standing and light-intensity activities. Patients will be recruited from the Clinical Hospital (School of Medicine, University of Sao Paulo) and will be assessed at baseline and after a 4-month follow up. Outcomes will include objectively measured sedentary behavior (primary outcome) and physical activity levels, clinical parameters, anthropometric parameters and body composition; aerobic fitness, muscle function, blood pressure, cardiovascular autonomic function, vascular function and structure, health-related quality of life, and food intake. Blood and muscle samples will be collected for assessing potential mechanisms, through targeted and non-targeted approaches.DiscussionFindings will be of scientific and clinical relevance with the potential to inform new prescriptions focused on reducing sedentary behavior, a modifiable risk factor that thus far has been overlooked in patients with rheumatoid arthritis.Trial registrationClinicalTrials.gov, NCT03186924. Registered on 14 June 2017.

Range of Yoga Intensities From Savasana to Sweating: A Systematic Review.

There is limited research examining the intensity of yoga and intensity variations between different styles. The purpose of this review is to examine the intensity of yoga based on different physiologic responses both between different yoga styles and within styles of yoga. Articles were searched for on the PubMed database in early 2019. Inclusion criteria were as follows: (1)written in English, (2)cite a specific style of yoga and include whole yoga session, and (3)measure metabolic or heart rate response. Ten articles were reviewed; articles reported oxygen consumption (n = 1), heart rate (n = 4), or both variables (n = 5). Yoga styles assessed included ashtanga (n = 2), Bikram (n = 3), gentle (n = 1), hatha (n = 3), Iyengar (n = 1), power (n = 1), and vinyasa (n = 1). Oxygen consumption commonly categorized yoga as a light-intensity activity, while heart rate responses classified different yoga into multiple intensities. This review demonstrates that large differences in intensity classifications are observed between different styles of yoga. Furthermore, metabolic and heart rate responses can be variable, leading to inconsistent intensity classifications. This is likely due to their nonlinear relationship during yoga. Thus, it is imperative that the field of yoga research works together to create a standard for reporting yoga.

Physical Activity Measurement Using Accelerometer in Phase-I Cardiac Rehabilitation

Background: Cardiovascular disease (CVD) is the leading cause of death and disability worldwide. Cardiac rehabilitation (CR) is important in improving cardiovascular fitness. Estimating physical activity (PA) levels and Energy Expenditure(EE) in Phase-I CR using Accelerometer can help in understanding cardiovascular fitness better. Method and Materials: PA of 16 participants post Coronary Artery Bypass Graft (CABG) and Percutaneous Transluminal Coronary Angioplasty (PTCA) in Phase-I CR was measured using Actigraph accelerometer. Metabolic Equivalents (METs) and average of daily EE(in Kcals) and steps taken were calculated. Correlation of the Six minute walk distance (6MWD) on the day of discharge and PA levels measured by Actigraphaccelerometer was done. Results: PA energy expenditure averaged 283.71 Kcals/3days, step counts/day 4861.50, METs 5.79 and the EE in light and moderate intensity activities were 1.01 Kcals and 5.72 Kcals respectively. The time spent in these activities were 62.25 minutes in light intensity and 2 minutes in moderate intensity activities. Conclusion: PA measured by Actigraph accelerometer was of low to moderate levels in Phase-I CR. There was a weak correlation between PA levels measured by Actigraph accelerometer and 6MWD achieved at the time of discharge.

Associations of physical activity in detailed intensity ranges with body composition and physical function. a cross-sectional study among sedentary older adults

BackgroundPhysical activity is crucial to maintain older adults’ health and functioning, but the health benefits of particular activity intensities remain unclear. The aim of this cross-sectional study was to peruse the distribution of physical activity, and to investigate the associations of particular physical activity intensities with body composition and physical function among older adults.MethodsThe sample comprised of 293 community-dwelling sedentary or at most moderately active older adults (42% men, mean age 74 ± 4 years). Physical activity was measured with a hip-worn tri-axial accelerometer over seven consecutive days, and investigated in detailed intensity range and in categories of sedentary, light and moderate-to-vigorous activity. Fat percent and appendicular lean mass were measured with DXA. Physical function was assessed by six-minutes walking test (6-min walk), maximal walking speed over 10 m (10-m walk) and Short Physical Performance Battery (SPPB). Associations were estimated with partial correlation adjusted for sex and age.ResultsParticipants spent on average 602 min per day sedentary, 210 min in light activity and 32 min in moderate-to-vigorous activity. Light and moderate-to-vigorous activity were negatively associated with fat percent (r = − 0.360 and r = − 0.384, respectively, p < 0.001 for both), and positively with SPPB, 10-m walk and 6-min walk results (r = 0.145–0.279, p < 0.01, for light and r = 0.220–0.465, p < 0.001, for moderate-to-vigorous activity). In detailed investigation of the intensity range, associations of physical activity with fat percent, 6-min walk and 10-m walk were statistically significant from very light intensity activity onward, whereas significant associations between physical activity and SPPB were observed mostly at higher end of the intensity range. Sedentary time was positively associated with fat percent (r = 0.251, p < 0.001) and negatively with 6-min walk (r = − 0.170, p < 0.01).ConclusionPerusing the physical activity intensity range revealed that, among community-dwelling sedentary or at most moderately active older adults, physical activity of any intensity was positively associated with lower fat percent and higher walking speed over long and short distances. These findings provide additional evidence of the importance of encouraging older adults to engage in physical activity of any intensity. More intervention studies are required to confirm the health benefits of light-intensity activity.

Change in device-measured physical activity assessed in childhood and adolescence in relation to depressive symptoms: a general population-based cohort study

AimEvidence for a link between physical activity and mental health in young people is hampered by weak evidence. Using repeat assessments of device-measured physical activity, we examined the association of...