Time In Light Activity Research Articles

Adult Sports Participation and Physical Activity: How About Curling?

Despite its well-documented physical and psychosocial benefits, sport remains the least engaged form of physical activity (PA) among adults. Many adults may lack the skills needed to play or continue to play sports and aging adults are more likely to avoid participation for fear of poor performance or injury. A sport that shows great promise for adults seeking new sports participation outlets is curling. Curling is a team sport comprised of four interchangeable positions working collectively to deliver granite stones across a sheet of ice in an effort to outscore the opponent team. While it seems reasonable that walking on ice, “throwing” a 44 lb granite stone across a sheet of ice, and periodically sweeping while walking on ice over a two-hour period would generate at least a moderate amount of physical activity, research to date is quite limited. Therefore, the purpose of this study was to objectively measure the amount and intensity of PA achieved by average recreational curling participants during a typical curling match. Methods Members of a curling club in NC were asked to wear Actigraph Accelerometers (model GT3X) while they participated in their regularly scheduled curling match. All participants had at least one year of curling experience. Curling matches lasted between 90 and 120 minutes. Participants were asked to indicate their age, gender, and curling position during the match (lead, second, vice, skip) which were matched with accelerometer data. Results Overall, 110 participants (37 female, 73 male, avg. age 50 yrs) spent most of their curling time in light or moderate-intensity activity (18.1% Sedentary; 49.5% light; 32.4% moderate; .03% vigorous). In terms of minutes, the average participant spent 35.9 minutes engaged in Moderate-to-Vigorous PA (MVPA) per curling experience. This represents 23.9% of the weekly 150min of MVPA suggested by the CDC. The second position had the highest percentage of moderate activity level and a small percentage of vigorous activity. No other position reached a vigorous level. The skip position had the highest amount of sedentary activity as well as light activity. Females had a higher level of moderate activity in comparison to males. However, males reached a small amount of vigorous activity. The age group of 18 - 36 had the highest amount of moderate activity and the lowest amount of sedentary activity. This age group reached an average of 41.0 minutes of MVPA per curling experience. The age group of > 58 had the highest amount of sedentary activity and the lowest amount of moderate activity. Conclusions Curling may be a good sports participation option for adults looking for alternatives to meet recommended weekly amounts of MVPA. Participants should consider playing in one of the first three positions to maximize the amount and intensity of PA achieved while playing. Furthermore, since curling also requires balance, coordination, muscular strength, multitasking, strategic reasoning, and can cater to most physical challenges without compromising the integrity of the game, it may be an ideal sport to promote for adults of all ages and sport abilities. Implications for Practice and Policy Findings should be used to inform strategies for promoting curling as an opportunity for team sport involvement that has the added value of contributing to daily physical activity. However, , access and opportunities to play, especially for underserved populations, are limited. Given that most curling clubs in America are private and require a membership to play. Partnership arrangements between existing clubs and public parks and recreation departments could increase both access and opportunities to play.

Daily and Weekly Associations Among Pain Intensity, Self-Reported Activity Limitations, and Objectively Assessed Physical Activity in Youth With Acute Musculoskeletal Pain

Monitoring recovery during acute pain episodes is useful for identifying youth at risk for pain persisting. Subjective and objective measures can assess function postinjury, but associations among these different measures and pain patterns in the acute period are unknown. To fill this gap, we examined associations among self-reported activity limitations, objectively measured physical activity, and pain intensity in 176 youth (age 11–17, 46% male) seeking health care for acute musculoskeletal pain. Participants completed 7-day electronic diaries rating daily pain intensity and activity limitations (Child Activity Limitations Interview [CALI]) while concurrently wearing an Actiwatch to record physical activity. The results revealed youth reported pain on 47.8% of days with an average intensity of 33.4 (0–100). Averaged across the week, between-participant analyses showed greater activity limitations were associated with lower mean (rActive = −.204, rRoutine = −.159, P < .05) and peak activity (rActive = −.291, rRoutine = −.184, P < .05). Same-day correlations between CALI scores and physical activity measures within participants were not significant. Linear mixed-effects models revealed higher daily pain intensity was associated with greater self-reported activity limitations on Routine (β = .23, P < .001) and Active CALI-9 subscales (β = .07, P < .001). Conversely, higher daily pain was associated with higher activity on actigraphy, specifically higher mean activity (β = .46, P < .01), more activity bouts (β = .013, P < .01), more time in light activity (β = .04, P < .01), and less sedentary time (β = −.04, P < .01). Taken together, self-reported activity limitations and objective physical activity represent 2 distinct, yet related, aspects of physical functioning associated with pain. Future work should examine how physical activity and activity limitations change longitudinally and predict pain persistence. PerspectiveThis study examined daily associations between pain intensity, self-reported activity limitations, and objectively assessed physical activity in youth during the acute recovery period following a musculoskeletal injury. Self-reported activity limitations and objective physical activity represent 2 distinct, yet related, aspects of physical functioning that are associated with pain.

Prediction of Mild Cognitive Impairment Status: Pilot Study of Machine Learning Models Based on Longitudinal Data From Fitness Trackers.

Early signs of Alzheimer disease (AD) are difficult to detect, causing diagnoses to be significantly delayed to time points when brain damage has already occurred and current experimental treatments have little effect on slowing disease progression. Tracking cognitive decline at early stages is critical for patients to make lifestyle changes and consider new and experimental therapies. Frequently studied biomarkers are invasive and costly and are limited for predicting conversion from normal to mild cognitive impairment (MCI). This study aimed to use data collected from fitness trackers to predict MCI status. In this pilot study, fitness trackers were worn by 20 participants: 12 patients with MCI and 8 age-matched controls. We collected physical activity, heart rate, and sleep data from each participant for up to 1 month and further developed a machine learning model to predict MCI status. Our machine learning model was able to perfectly separate between MCI and controls (area under the curve=1.0). The top predictive features from the model included peak, cardio, and fat burn heart rate zones; resting heart rate; average deep sleep time; and total light activity time. Our results suggest that a longitudinal digital biomarker differentiates between controls and patients with MCI in a very cost-effective and noninvasive way and hence may be very useful for identifying patients with very early AD who can benefit from clinical trials and new, disease-modifying therapies.

Patterns of physical activity of people with COPD during participation in a pulmonary rehabilitation program

IntroductionVery few studies have examined patterns of physical activity (PA) during a pulmonary rehabilitation (PR) program in people with COPD. AimsTo compare the patterns of PA in: 1) the week before commencing PR (pre-PR) with a week during PR (PR week); 2) PR days and non-PR days during a PR week; 3) pre-PR and the week following PR completion (post-PR). MethodsThis was a multicenter, prospective cohort study. Participants attended twice weekly supervised PR for 8–12 weeks. Daily step count (primary outcome), time in light activities, time in moderate to vigorous PA (MVPA), total sedentary time and sit-to-stand (STS) transitions were measured using a thigh worn accelerometer for seven days, at each assessment time point: pre-PR, PR week and post-PR. Results29 participants, mean age (SD) 69years(7), FEV1 53%pred(16). The PR week compared to pre-PR, showed higher daily: step count (mean difference (95%CI)), 941steps(388–1494); and MVPA, 11mins(6–15), with no difference in: time in light activities, -1min(-6–5); total sedentary time, 7mins(-21–36); or STS transitions, 0(-5–6). PR days compared to non-PR days showed higher: step count, 2810steps(1706–3913); time in light activities 11mins(1–20); time in MVPA, 27mins(17–35) and STS transitions, 8(4–12), with no difference in total sedentary time: −33mins(-80–15). There were no differences in any PA measures post-PR compared to pre-PR (p < 0.05). ConclusionDaily step count and time spent in MVPA increased significantly during the PR week, solely due to increased PA on days participants attended PR.

Sedentary behaviour (especially accumulation pattern) has an independent negative impact on skeletal muscle size and architecture in community-dwelling older adults.

Prolonged sedentary behaviour (SB) i.e. longer bouts, is suggested to have a range of negative health effects, independent of habitual light and medium-to-vigorous physical activity (LIPA or MVPA). Any effect on musculoskeletal size, architecture or morphology has seldom been reported in older adults. Moreover, no study has yet determined if any association would persist following adjustment for covariates. Therefore, the aim of the present study was to investigate the associations between SB, and properties of the Gastrocnemius Medialis (GM) muscle, in a cross-sectional sample of older adults using compositional data analysis. 105 healthy older adults (73±6y) wore a thigh mounted tri-axial accelerometer for seven consecutive days, and underwent ultrasound [e.g. muscle length (Lm), anatomical cross-sectional area (ACSA), muscle volume (VM), fascicle length (LF), & physiological cross-sectional area (PCSA)], body composition (e.g. DEXA) and health (e.g. medical history) assessments. In-unadjusted models, SB time was negatively associated with ACSA at 75% of Lm (R2adj = 0.085), VM (R2adj = 0.020), and PCSA (R2adj = 0.039). Standing was positively associated with pennation angle (R2adj = 0.110), which persisted following co-variate adjustment (R2adj = 0.296). In fully adjusted models, both SB & LIPA time were associated with ACSA at 75% of Lm (Both R2adj = 0.393). Standing and light activity time were also associated with LF, VM, & PCSA (R2adj 0.116-0.573). In fully adjusted models, SB pattern parameters (i.e. the manner in which sedentary behaviour is accumulated daily throughout waking hours such as the timing, duration and frequency of sedentary bouts), were associated with GM muscle properties (R2adj 0.156-0.564) including LM, LF, and VM. The pattern, rather than accumulated daily SB time, was associated with the size and architecture of the GM. Our results suggest that regardless of co-existing habitual physical activities, SB bouts should be kept short and frequently interrupted to offset some of the deleterious ageing-related muscle architecture characteristics changes.

Physical Activity Level of Ambulatory Stroke Patients and its Correlation with their Functional Abilities

Abstract Introduction: Stroke management guidelines include physical activity recommendations as physical activity has proven benefits for stroke prevention and management. Studies from the various parts of the world have reported stroke survivors do not reach the recommended level of physical activity. Personal and environmental factors might be contributing to the same. A person’s ability is a prerequisite for being active. Thus, there is a need to evaluate the physical activity levels of stroke survivors and find how functional abilities correlate with physical activity. Aim: This study aims to measure objectively measured physical activity of stroke survivors and evaluate its correlation with functional abilities. Methodology: The study included 108 ambulatory stroke patients. Functional abilities were measured for independence in daily living, gait speed, and endurance by the Barthel Index, 10-m walk test, and 6-min walk test, respectively. Physical activity of all the participants was measured by accelerometer ActiGraph wGT3X-BT. Results: The study participants were found to spend higher time in sedentary or light activities. They spent 45.3% ± 5.432% of their day sedentary and 42.72% ± 5.494% of the time in light activities. The study participants took 7795.6 ± 2669.9 steps and spent 200.27 ± 68.60 kcal in a day. Physical activity parameters step counts and energy expenditure in metabolic equivalent rate and kcal/day show a statistically significant correlation with functional ability parameters except for energy expenditure in kcal for the day and independence in activities of daily living. Conclusion: As reported with other studies, our study participants also report low physical activity as compared to the recommendation. Functional ability parameters gait speed and gait endurance show moderate correlation and independence in activities of daily living shows low or no correlation with physical activity parameters. There is a strong need to increase physical activity among stroke participants.

Early Moderate to Vigorous Physical Activity After Concussion Is Associated With Faster Symptom Resolution Time.

Early physical activity (PA) after concussion may promote symptom resolution. Prior studies have investigated exercise frequency/duration, yet precise PA intensity or volume required for optimal recovery requires further investigation. moderate to vigorous physical activity (MVPA) is beneficial for physical health. We investigated whether sedentary time, light activity time, MVPA time, or activity frequency in the weeks following concussion are associated with time to symptom resolution among adolescents. Prospective cohort study. Adolescents 10-18years of age were tested ≤14days of concussion and followed until symptom resolution. At the initial visit, participants rated symptom severity and were provided wrist-worn activity trackers to monitor PA for the following week. PA behavior was categorized each day based on heart rate: sedentary (resting), light PA (50%-69% age-predicted max heart rate), and MVPA (70%-100% age-predicted max heart rate). Symptom resolution was defined as the date when participants reported cessation of concussion-like symptoms. Patients were not given specific PA instructions, though some may have received instructions from their physician. Fifty-four participants were included in the study (54% female; mean age = 15.0 [1.8]y; initially assessed 7.5 [3.2]d after concussion). Female athletes recorded more sedentary time (900 [46] vs 738 [185]min/d; P = .01; Cohen d = 0.72), and less time in light PA (194.7 [64.5] vs 224 [55]min/d; P = .08; Cohen d = 0.48) and MVPA (23 [17] vs 38 [31]min/d; P = .04; Cohen d = 0.58) than male athletes. After adjusting for sedentary time, hours per day with >250 steps, sex, and initial symptom severity, more MVPA time was associated with faster symptom resolution time (hazard ratio = 1.016; 95% confidence interval, 1.001-1.032; P = .04). Our findings offer preliminary insight into how varying PA intensities affect concussion recovery, as MVPA may be a higher intensity than what is typically prescribed in concussion care.

Significantly Lower Physical Activity Participation in Individuals with Chronic Pancreatitis Compared to Controls: An Exploratory Study of Objectively Assessed Physical Activity Levels

Introduction: The beneficial effects of exercise and physical activity (PA) have been demonstrated in many chronic inflammatory diseases. Knowledge on PA levels is unknown in the chronic pancreatitis population, and there are currently no specific PA recommendations for this condition. Methods: PA was measured objectively over a 7-day period in 17 individuals with chronic pancreatitis using an accelerometer (ActiGraph) and in 15 controls, matched for age, sex, and body mass index. Results: Participants with chronic pancreatitis spent a significantly lower amount of time in moderate, light, and moderate/vigorous activity compared to the healthy control group. Mean time in light activity in the chronic pancreatitis group was 825.4 ± 972 (standard deviation [SD]) compared to 1,500 ± 958 (SD) in the healthy control group. Moderate activity mean minutes were 61.6 ± 85 in the chronic pancreatitis group compared to 161.4 ± 131.2 in the healthy control group. Moderate/vigorous mean minutes were 62.1 ± 86 (SD) in the chronic pancreatitis group compared to 164.3 ± 132 (SD) in the healthy control group. There was no significant difference found between the groups for either vigorous activity or time spent sedentary. Conclusion: This exploratory study offers early objective evidence that activity levels in the chronic pancreatic group are not meeting current international recommendations. Further investigation of this chronic illness population is strongly recommended.

Joint associations of peripheral artery disease and accelerometry-based physical activity with mortality: The Hispanic Community Health Study/Study of Latinos (HCHS/SOL)

Background and aimsPeripheral artery disease (PAD) and lower levels of physical activity are both associated with higher mortality. Yet, their joint prognostic impact has not been systematically examined, especially in Hispanics/Latinos, and with objective measures. We aimed to examine the joint associations of PAD and physical activity with mortality in the Hispanic Community Health Study/Study of Latinos (HCHS/SOL). MethodsWe studied 7,620 Hispanic/Latino adults aged 45–74 years at baseline (2008–2011) who underwent assessment of PAD with ankle-brachial index (ABI) and physical activity with hip-worn accelerometry. We calculated four physical activity measures: sedentary time, light activity, moderate/vigorous activity, and total activity counts. We quantified the relationship between ABI and mortality overall, and by tertiles of activity measures in restricted cubic splines, using multivariable Cox models accounting for sampling weights. We also assessed cross-categories of ABI and activity measures with mortality. ResultsDuring a median follow up of 7.1 years, 314 participants died. We observed a U-shaped association of ABI with mortality overall (e.g., hazard ratio 1.80 [95%CI 1.20–2.80] at ABI 0.7 vs 1.2). This U-shaped association was generally consistent after stratifying by activity measures, but an elevated mortality risk for higher ABI was not evident in the most active tertile based on sedentary time, time in light activity, and total activity counts. In the cross-category analysis of ABI and physical activity, the highest mortality risk was consistently seen in abnormal ABI (≤0.9 or >1.4) plus the least active tertile (e.g., HR 5.61 [3.31–9.51] for light activity), compared to referent ABI (0.9–1.4) plus the other more active two tertiles, with no interactions between ABI and activity measure. ConclusionsAbnormal ABI and lower accelerometry-based physical activity were independently and jointly associated with mortality in Hispanics, suggesting the importance of simultaneously evaluating leg vascular condition and physical activity.

Accelerometer-Measured, Habitual Physical Activity and Circulating Brain-Derived Neurotrophic Factor: A Cross-Sectional Study.

One of the mechanisms suggested to link physical activity (PA) to favorable brain health is through stimulation of neural growth factors such as brain-derived neurotrophic factor (BDNF). Acute bouts of PA stimulate circulating BDNF levels. In this investigation, we assessed whether habitual, accelerometer-measured PA levels were related to circulating BDNF levels in a middle-aged cohort. In the Framingham Heart Study Third Generation cohort, 1,769 participants provided reliable accelerometry data and were not missing BDNF measurement or platelet counts. In a cross-sectional analysis, using multivariable regression, we related PA measures to serum BDNF levels, adjusting for age, sex, smoking status, platelet count, depression status, and accelerometer wear time. Our study participants (mean age 47±9 years, 50.8% women) spent an average of 22.3 mins/day in moderate-to-vigorous (MV)PA. Most PA variables (steps, MVPA, light activity, and sedentary time) were not related to BDNF levels (p > 0.05). We observed a non-linear trend, where 15-50 mins/week vigorous activity was associated with lower BDNF compared to those with 0 min vigorous activity (β= -0.049±0.024, p = 0.05), but with no significant associations at lower or higher vigorous activity levels. In smokers, MVPA was also associated with lower BDNF levels (β= -0.216±0.079, p = 0.01). Our study reveals that circulating BDNF is not chronically elevated in individuals with higher levels of habitual PA in middle-aged adults from the community and may even be chronically suppressed with higher PA in subgroups, including current smokers. These results do not contradict previous studies demonstrating that circulating BDNF rises acutely after PA.

Validity and Acceptability of Wearable Devices for Monitoring Step-Count and Activity Minutes Among People With Multiple Sclerosis.

Multiple wearable devices that purport to measure physical activity are widely available to consumers. While they may support increases in physical activity among people with multiple sclerosis (MS) by providing feedback on their performance, there is little information about the validity and acceptability of these devices. Providing devices that are perceived as inaccurate and difficult to use may have negative consequences for people with MS, rather than supporting participation in physical activity. The aim of this study was, therefore, to assess the validity and acceptability of commercially available devices for monitoring step-count and activity time among people with MS. Nineteen ambulatory adults with MS [mean (SD) age 52.1 (11.9) years] participated in the study. Step-count was assessed using five commercially available devices (Fitbit Alta, Fitbit Zip, Garmin Vivofit 4, Yamax Digi Walker SW200, and Letscom monitor) and an activPAL3μ while completing nine everyday activities. Step-count was also manually counted. Time in light activity, moderate-to-vigorous activity, and total activity were measured during activities using an Actigraph GT3X accelerometer. Of the 19 participants who completed the validity study, fifteen of these people also wore the five commercially available devices for three consecutive days each, and participated in a semi-structured interview regarding their perception of the acceptability of the monitors. Mean percentage error for step-count ranged from 12.1% for the Yamax SW200 to −112.3% for the Letscom. Mean step-count as manually determined differed to mean step-count measured by the Fitbit Alta (p = 0.002), Garmin vivofit 4 (p < 0.001), Letscom (p < 0.001) and the research standard device, the activPAL3μ (p < 0.001). However, 95% limits of agreement were smallest for the activPAL3μ and largest for the Fitbit Alta. Median percentage error for activity minutes was 52.9% for the Letscom and 100% for the Garmin Vivofit 4 and Fitbit Alta compared to minutes in total activity. Three inductive themes were generated from participant accounts: Interaction with device; The way the device looks and feels; Functionality. In conclusion, commercially available devices demonstrated poor criterion validity when measuring step-count and activity time in people with MS. This negatively affected the acceptability of devices, with perceived inaccuracies causing distrust and frustration. Additional considerations when designing devices for people with MS include an appropriately sized and lit display and ease of attaching and charging devices.

Changes in physical activity across a 6-month weight loss intervention in adolescents with intellectual and developmental disabilities.

Adolescents and young adults with intellectual and developmental disabilities (IDD) have high rates of obesity and low levels of physical activity. This analysis examined changes in light, moderate-to-vigorous physical activity (MVPA) and sedentary time, and the association between changes in MVPA and weight loss in adolescents and young adults with IDD and overweight and obesity participating in a 6-month multi-component weight loss intervention. Adolescents and young adults with IDD and overweight or obesity (body mass index≥85 percentile, n=110, age ~16years, 52.7% female) and a parent were randomised to one of three intervention groups: face-to-face delivery/conventional reduced energy diet (n=36), remote delivery (RD)/conventional reduced energy diet (n=39), or RD/reduced energy enhanced stop light diet (eSLD) (n=35.) Participants were asked to engage in 60min/day of MVPA on 5 or more days/wk. Participants and a parent attended twice monthly education/behavioural counselling sessions with a health educator to assist participants in complying with dietary and MVPA recommendations. Education/counselling in the RD arms was delivered remotely using video conferencing, and self-monitoring of MVPA and daily steps was completed using a wireless activity tracker. Education/counselling in the face-to-face arm was delivered during home-visits and self-monitoring of MVPA and daily steps was completed by self-report using paper tracking forms designed for individuals with IDD. MVPA, light activity, and sedentary time were assessed over 7days at baseline and 6months using a portable accelerometer (ActiGraph wGT3x-BT). Mixed modelling analysis completed using participants with valid accelerometer data (i.e. ≥4-10h days) at baseline (n=68) and 6months (n=30) revealed no significant changes in light, moderate- MVPA, or sedentary time across the 6-month intervention (all P>0.05). Participants obtained 15.2±21.5min/day of MVPA at baseline and 19.7±19.7min/day at 6months (P=0.119). Mixed modelling indicated no significant effects of group (P=0.79), time (P=0.10), or group-by-time interaction (P=0.21) on changes in MVPA from baseline to 6months. Correlational analysis conducted on participants with valid accelerometer data at both baseline and 6months (n=24) revealed no significant associations between baseline sedentary time (r=0.10, P=0.40) and baseline MVPA (r=-0.22, P=0.30) and change in MVPA across the 6-month intervention. Additionally, attendance at education/counselling sessions (r=0.26, P=0.22) and frequency of self-monitoring of MVPA were not significantly associated with change in MVPA from baseline to 6months (r=0.26, P=0.44). Baseline MVPA (r=0.02, P=0.92) and change in MVPA from baseline to 6months (r=0.13, P=0.30) were not associated with changes in body weight across the 6-month intervention. We observed a non-significant increase in MVPA (30%), which was not associated with the magnitude of weight loss in a sample of adolescents and young adults with IDD who participated in a 6-month multi-component weight loss intervention. Additional strategies to increase MVPA in adolescents and young adults with IDD participating in weight loss interventions need to be developed and evaluated.

Physical activity and sedentary time in a multimodal lifestyle intervention in prodromal Alzheimer’s disease: The MIND‐ADMINI pilot trial

AbstractBackgroundAlzheimer’s disease (AD) is multifactorial. Interventions simultaneously targeting multiple risk factors are most likely to be effective, as demonstrated in the 2‐year Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability (FINGER). While patients with prodromal AD represent a group with high risk of progressing to dementia, no trials have tested the feasibility of multimodal interventions in prodromal AD. The main purpose of the MIND‐ADMINI was to evaluate the overall adherence to such multimodal intervention. This sub‐study focuses on exploratory outcomes which included physical performance and physical activity (PA) levels.MethodMIND‐ADMINI is a 6‐month multicenter (Sweden, Finland, Germany, France) randomized controlled pilot trial. Participants with prodromal AD, between 60 and 85 years were randomized into three groups: usual care (control (C)), multidomain lifestyle intervention combining nutritional guidance, cognitive training, exercise, and careful monitoring of vascular risk factors (ML), or multidomain lifestyle intervention+medical food (ML+MF) (Fortasyn Connect). The multidomain lifestyle intervention was based on the FINGER model and included a progressive aerobic‐ and strength training program. Moderate to vigorous physical activity (MVPA), light activity, step counts, and time (min/day) spent sedentary were evaluated using data from a hip‐worn accelerometer. For each outcome, 6‐month values were regressed on baseline to estimate change.ResultsBaseline accelerometry data was available for 66 of 69 participants in Sweden, Finland, and France. At the 6‐month follow‐up, accelerometry data from 55 participants was included. At baseline mean age (SD) was 72,9 (6,2) years, 50,7% were men, and MMSE score was 27,6 (1,6) points. No significant values were found. At follow‐up, all groups increased their sedentary time, C (8,3%), ML (9,3%) and ML+MF (1,6%). Increased step count (3,4%) time in MVPA (2,8%) and light activity (9,5%) was observed during follow‐up in the ML+MF group.ConclusionsMeasurement of physical activity level using a hip‐worn accelerometer was feasible in this population. The observed increased time in MVPA, light activity and step counts in ML+MF group at the same time as sedentary time increased in all three groups between baseline and 6‐months follow‐up highlight the importance of physical activity as a part of multidomain lifestyle interventions in persons with prodromal AD.

Abstract 11289: Sedentary Time in Uganda: Influence of Sex and HIV Status and Associations with Atherosclerotic Cardiovascular Disease Risk

Introduction: Sub-Saharan Africa (SSA) is disproportionately impacted by HIV and HIV-related atherosclerotic cardiovascular disease (ASCVD). Since physical activity may prevent ASCVD events, it is important to understand how physical activity and inactivity relate to ASCVD risk among men and women with and without HIV in SSA. Methods: One hundred people with HIV (PWH) and 100 people without HIV (PWOH) matched by age and sex were enrolled into this observational study in Kampala, Uganda. Physical activity was objectively measured by actigraphy for 7 days, including steps per day, light activity time, moderate-to-vigorous activity time and sedentary time. ASCVD risk was assessed using the pooled-cohort equations. Coronary artery disease was quantified by cardiac computed tomography angiography. Multivariable linear and logistic regression models were used to determine the relationship between physical activity, ASCVD risk, and subclinical coronary disease. Results: Median age was 57 years; 63% were female and median ASCVD risk score was 7.9%. All PWH were on antiretroviral therapy and 86% had undetectable HIV viral load. Physical activity patterns were similar by HIV status (all p&gt;0.2). Compared to males, females took more steps per day ( p =0.001) and engaged in more light activity time ( p &lt;0.001), but less moderate-to-vigorous activity time ( p &lt;0.001). Sedentary time was similar by HIV status and sex (both p&gt;0.8). After adjusting for moderate-to-vigorous activity time, sedentary time remained positively associated with ASCVD risk (standardized β=0.334, p &lt;0.001). In stratified models, sedentary time was associated with ASCVD risk in females (β=0.258, p =0.028) but not males (p=0.194) and in PWOH (β=0.430, p=0.001) but not PWH (p=0.380). Sedentary time was associated with the presence of coronary artery disease plaque, even after adjustment for ASCVD risk score (adjusted OR= 1.039 per hour of sedentary time, p =0.018). Conclusions: Sedentary time is strongly associated with atherosclerotic cardiovascular disease risk in Uganda, particularly among females, but less so among PWH. Future studies should consider the influence of sex and HIV status while developing targeted strategies to improve physical activity and reduce sedentary time.

Comparison of chest- and wrist-based actigraphy in pulmonary arterial hypertension.

Activity trackers for clinical trials and remote monitoring are appealing as they provide objective data outside of the clinic setting. Algorithms determine physical activity intensity and count steps. Multiple studies show physical inactivity in pulmonary arterial hypertension (PAH). There are no studies comparing different activity trackers worn on different parts of the body in PAH. We had patients with PAH simultaneously wear two different accelerometers, compared measures between the two devices, and correlated the measures with standard clinical metrics in PAH. This was a single-centre, prospective observational study. Daily physical activity and daily total steps were measured using Actigraph GT9X Link and MC10 Biostamp nPoint for 5-10 days. Actigraph was worn on the non-dominant hand and the MC10 Biostamp nPoint was worn on the chest and leg with disposable adhesives. Twenty-two participants wore both accelerometers >12 h/day for an average 7.8 days. The average activity time measured by Actigraph was significantly higher than that measured by MC10 (251 ± 25 min vs. 113 ± 18 min, P = 0.0001). Actigraph's algorithm reported more time in light activity than moderate (190 ± 62 min vs. 60 ± 56 min, P = 0.0001). REVEAL 2.0 scores correlated highly with activity time measured using either device. Invasively measured haemodynamics within 7 days did not correlate with activity time or daily steps. Different activity trackers yield discordant results in PAH patients. Further studies are needed in determining the best device, optimal wear time, and different thresholds for activities in chronic diseases.

1113Depressive symptoms and objectively measured physical activity and sedentary behaviour in adolescents

Abstract Background Physical activity and sedentary behaviour could be crucial risk factors for adolescent depression. This is the first study to use objective physical activity and sedentary behaviour measure to examine their association with depression in adolescents. Methods We analysed accelerometer data from population-based adolescents at ages 12, 14, and 16 and depressive symptoms at age 18. We used negative binomial regression and group-based trajectory models to analyse the data. Results We found that total physical activity decreased between 12 years and 16 years of age, driven by a decline in light activity and increase in sedentary behaviour. Each additional 60-minute increase in daily sedentary behaviour at ages 12, 14, and 16 was associated with an increased depression score at age 18 of 11·1% (95% CI, 5·1, 17·6), 8% (95% CI, 1·2, 15·2), and 10·5% (95% CI, 1·5, 20·8), respectively. Depression scores at age 18 were 9·6% (95% CI, 3·9, 15), 7.8% (95% CI, 0·8, 14.3), and 11·1% (95% CI, 2·6, 19.1) lower per additional 60-minutes of daily light activity time at ages 12, 14, and 16. These findings were robust to a series of sensitivity analyses. Conclusions Sedentary behaviour displaces light activity throughout adolescence and is associated with a higher risk of depressive symptoms at 18 years of age. Key messages Increasing light activity and decreasing sedentary behaviour during adolescence could be an important target for public health interventions aimed at reducing the prevalence of depression.

Effects of Physically Active Lessons on Movement Behaviors, Cognitive, and Academic Performance in Elementary Schoolchildren: ERGUER/Aracaju Project.

To evaluate the effects of the introduction of physically active lessons on movement behaviors, cognitive, and academic performance in schoolchildren. This was a cluster-controlled trial. A total of 61 students from the second year of elementary school in a public school in Brazil made up 2 intervention classes (n = 34) with the introduction of physically active lessons and 2 control classes (n = 27). Sedentary behavior, physical activity, cognitive, and academic performance were evaluated in 3 moments, which were compared using models of generalized estimating equations. The intervention was effective for reducing the standing time between the baseline and 3months while increasing the walking time between baseline and 3months and baseline and 9months. There was a reduction in time in stationary activities and increased time in light physical activities between all moments. The intervention group increased their performance in the go/no go test, showing a smaller number of errors between the baseline and 3months and baseline and 9months, and a reduction in the test time between baseline and 3months. No impact on students' academic performance was observed. Physically active lessons improve movement behaviors and cognitive functions among elementary schoolchildren.

Stand Out in Class: Investigating the Potential Impact of a Sit-Stand Desk Intervention on Children's Sitting and Physical Activity during Class Time and after School.

Sedentary behaviour (sitting) is a risk factor for adverse health outcomes. The classroom environment has traditionally been associated with prolonged periods of sitting in children. The aim of this study was to examine the potential impact of an environmental intervention, the addition of sit–stand desks in the classroom, on school children’s sitting and physical activity during class time and after school. The ‘Stand Out in Class’ pilot trial was a two-arm cluster randomised controlled trial conducted in eight primary schools with children from a mixed socioeconomic background. The 4.5 month environmental intervention modified the physical (six sit–stand desks replaced standard desks) and social (e.g., teachers’ support) environment. All children wore activPAL and ActiGraph accelerometers for 7 days at baseline and follow-up. In total 176 children (mean age = 9.3 years) took part in the trial. At baseline, control and intervention groups spent more than 65% of class time sitting, this changed to 71.7% and 59.1% at follow-up, respectively (group effect p < 0.001). The proportion of class time spent standing and stepping, along with the proportion of time in light activity increased in the intervention group and decreased in the control group. There was no evidence of any compensatory effects from the intervention after school. Incorporating sit–stand desks to change the classroom environment at primary school appears to be an acceptable strategy for reducing children’s sedentary behaviour and increasing light activity especially during class time. Trial registration: ISRCTN12915848 (registered: 09/11/16).

Walking energetics and abductor strength are associated with physical activity in older women with hip osteoarthritis

BackgroundOsteoarthritis (OA) can hinder physical activity in older adults for reasons that are not fully understood. Functional barriers may exist such as reduced muscle strength around the affected joint, potentially affecting physical activity. Aging-associated declines in energy capacity may also be exacerbated by OA. These factors may work together to influence physical activity in people with OA. Research questionOur objective was to evaluate the combined role of walking energetics and hip abductor strength on physical activity in older women with hip OA. MethodsWe evaluated 30 women with moderately symptomatic hip OA (61 ± 10 yrs; 30.7 ± 4.9 kg/m2) in this cross-sectional observational study. We measured physical activity using the UCLA activity score and quantified activity frequency and intensity using accelerometers worn for seven days (7 ± 2 days). We used a portable oxygen exchange system to measure energy used during walking at preferred speeds (relative to total energy capacity assessed using a six-minute walk test) and a dynamometer to measure hip abductor strength. We used Pearson correlations and regression analysis to test our hypotheses. ResultsGreater energy used during walking was associated with lower self-reported physical activity (R=-0.626, p < 0.001), more sedentary time (R = 0.567, p = 0.002), and less light activity time (R=-0.644, p < 0.001). Lower hip abductor strength was associated with lower self-reported physical activity (R = 0.406, p = 0.039). While there was no association between hip abductor strength and energy used during walking, together these variables predicted 55.5 % of the variance in self-reported physical activity. SignificanceResults suggest intervention targets to promote physical activity in this population.

Contribution of Sleep Disruption and Sedentary Behavior to Fatigue in Survivors of Allogeneic Hematopoietic Cell Transplant.

Fatigue is a prominent quality of life concern among recipients of hematopoietic cell transplantation (HCT). The present study investigated whether objectively measured sleep efficiency and sedentary behavior are related to greater reports of fatigue. Eighty-two allogeneic HCT recipients who were 1-5 years post-transplant and returning for a follow-up visit participated (age M = 56, 52% female, 56% leukemia). They wore an actigraph assessing sleep efficiency and sedentary behavior for one week and completed an electronic log assessing fatigue each evening during the same period. Twenty-six percent of patients reported clinically meaningful fatigue. On average, fatigue was mild (M = 2.5 on 0-10 scale, SD = 2.0), sleep was disturbed (sleep efficiency M = 78.9%, SD = 8.9), and patients spent the majority of time in sedentary (M = 55.4%, SD = 10.2) or light (M = 35.9%, SD = 8.6) activity. Multilevel model analysis of between-person differences indicated that patients who experienced less efficient sleep the previous evening provided greater evening reports of average fatigue, b = -0.06, 95% CI (-0.11, -0.01). Similarly, within-person analyses indicated that when patients experienced less efficient sleep the previous evening or were more sedentary as compared to their average, they provided greater evening reports of average fatigue, b = -0.02, 95% CI (-0.05, -0.004); b = 4.46, 95% CI (1.95, 6.97), respectively. Findings demonstrate that poor sleep and daily sedentary behavior are related to evening reports of fatigue and should be considered modifiable targets for intervention.