Time In Light Activity Research Articles

Physical Activity as a Predictor of Chronic Pain Following Pediatric Spinal Surgery.

(1) Characterize objective physical activity patterns via actigraphy over 4 months postspinal fusion surgery, and (2) examine associations between activity patterns at 2-week and chronic postsurgical pain (CPSP) status at 4 months. Data from 109 youth (10 to 18 y) who underwent spinal fusion surgery at a children's hospital in the Northwestern United States were analyzed. Youth completed questionnaires and actigraphic assessment of physical activity presurgery, and 2 weeks and 4 months postsurgery. Eighteen percent of youth developed CPSP at 4 months. Presurgery physical activity was similar for youth with and without CPSP. At 2 weeks postsurgery, daily activity levels were lower for youth who developed CPSP as compared with those who did not, including lower mean activity (168 vs. 212 counts/min, P=0.01), fewer activity bouts (n=1.7 vs. 2.6, P=0.02), and shorter bout duration (27 vs. 40 min, P=0.02). Differences in activity were maintained at 4 months such that youth with CPSP had lower mean activity (284 vs. 334 counts/min, P=0.03), as well as greater proportion time spent sedentary and lower proportion time in light activity than youth without CPSP. In adjusted models examining 2-week actigraphy as a predictor of 4-month pain status, mean activity (odds ratio=0.99, P=0.04) and number of activity bouts (odds ratio=0.79, P=0.02) were associated with subsequent CPSP status over and above 2-week pain intensity. Lower activity engagement during the initial weeks following spinal fusion surgery was associated with development of CPSP, suggesting early physical activity limitations as a risk factor for CPSP in youth. Understanding recovery patterns is critical for identifying those at risk for chronic pain and implementing early interventions.

Daily Physical Activity in Children and Adolescents with Low Lumbar and Sacral Level Myelomeningocele

ABSTRACT Purpose Children with low lumbar and sacral level myelomeningocele are expected to be community ambulators. However, they do not always meet the expected ambulation level by the time they reach adulthood. The purpose of this study is to investigate daily activity energy expenditure and physical activity levels of these patients in daily routine. Materials and methods 20 patients and 20 healthy peers were included in this case-control study. Omnidirectional accelerometer monitor was used for assessing activity energy expenditure, and daily durations spent in sedentary, light activity, and moderate to vigorous physical activity levels (NCT04186338). Results Mean activity energy expenditure and moderate to vigorous physical activity duration were significantly lower in the patient group, while age was positively correlated with sedentary time and negatively correlated with light activity time. Conclusions In patients with myelomeningocele, increasing daily activity energy expenditure and moderate to vigorous physical activity and, especially as age progresses, decreasing the sedentary behavior may assist in providing the expected ambulation level. These patients should be encouraged to partake in regular exercise programs.

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.

Relationship of different intensities of physical activity and quality of life in postmenopausal women

BackgroundIt is known that the elderly population remains most of the time in light activity. Physical activity plays a key role in the primary prevention of chronic diseases to mitigate various deleterious effects of aging and improve quality of life. The objective of the present study was to evaluate whether the time that postmenopausal women remain in light activities during the day are related to better quality of life and compare these results with the quality of life of those who remain longer in moderate intensity and vigorous activity.MethodsThis is a cross sectional study there were evaluated 102 women, aged 50 to 79 years, all postmenopausal. Physical activity was measured by triaxial accelerometers. The quality of life was assessed using a Brazilian validated version of the SF-36 questionnaire. The sample was divided in three groups (G1, G2 and G3) according to tercile of time spent per week on light, moderate and moderate+vigorous physical activity. The comparisons between groups were made by ANOVA One Way, and the relationship between variables were made through the Spearman’s correlation coefficient, and the significance was set at 5%.ResultsWe found that the amount of time of light physical activity shows a higher correlation values compared to the moderate and moderate+vigorous physical activity (p < 0,05) and presented significant correlation in all domains of quality of life. Vigorous physical activity did not presented significant correlation in all domains of quality of life.ConclusionOur data suggests that light intensity physical activity presented influence on the quality of life of postmenopausal women.Trial registration(NCT02804308). Registered on 17 june 2016 (retrospectively registred).

Physical activity, sleep and neuropsychiatric symptom severity in children with tourette syndrome.

The purpose of this study was to examine associations between physical activity, sleep and symptom severity in children with tic disorders. Children with tic disorders wore the GeneActiv device, a wrist-worn accelerometer that measures physical activity intensity and sleep/wake parameters continuously for seven days, and completed questionnaires on sleep quality, exercise and severity of tics, ADHD, obsessive-compulsive behaviours, anxiety and depression. 110 children participated in the study. Children with more severe tics had significantly more frequent comorbid diagnoses, greater impairment in subjective sleep measures, greater sedentary activity time and less light, moderate and vigorous activity time (all p < 0.05). There was a significant negative correlation between light, moderate and vigorous physical activity and the severity of tics (- 0.22, p = 0.04), obsessive compulsive behaviours (- 0.22, p = 0.03), anxiety (- 0.35, p = 0.0005) and depression (- 0.23, p = 0.03). There was no correlation between objective sleep time, sleep efficiency and symptom severity. Subjective sleep quality was positively correlated with all symptom severity measures, with the strongest correlation with ADHD severity (0.42, p < 0.00001). The results of this observational study indicate a small, but significant relationship between activity and sleep measures and the severity of the main symptom domains present in tic disorders.

Physical activity and sedentary behavior in women with rheumatoid arthritis: a comparison of patients with low and high disease activity and healthy controls.

Objective: In rheumatoid arthritis (RA) patients, low levels of physical activity (PA) and high levels of sedentary behavior (SB) may play a role in enhancing cardiovascular risk. We do not know how long-term control of disease activity impacts upon daily PA levels and if treated patients attain PA levels seen in healthy controls. We therefore compared habitual levels of PA and SB between female RA patients with low disease activity achieved by anti-tumor necrosis factor (TNF) therapy, those with active arthritis (aRA) and non-RA controls.Methods: We carried out a cross-sectional comparison of 40 RA patients on anti-TNF therapy for >2 years with DAS28<3.2 (tRA), 32 patients on conventional disease modifying anti-rheumatic drugs with DAS28>3.2 (aRA) and 34 healthy controls (C) with the groups matched for age and body mass index. PA was assessed using the ActiGraph accelerometer to determine step count and time spent in moderate-to-vigorous physical activity (MVPA), light activity and sedentary time.Results: Daily step count was 72% higher in tRA and 40% higher in C in comparison to aRA (p<0.01). Sedentary time (as a proportion of wear time) was 10% less in tRA than aRA (p=0.03), while light activity time was 18% higher (p=0.014). Both RA groups had 40% lower MVPA time than C (p=0.001). Only half of either RA group fulfilled current WHO guidelines for PA compared with 82% of controls.Conclusion: RA patients who had long-term disease suppression were more physically active with less SB compared to RA patients with active disease. They had similar light PA and SB to controls although lower MVPA. Behavioral change interventions are likely to be needed in order to restore moderate exercise, further reduce SB and to meet guidelines for daily PA.

Functional limitations, sedentary time and light physical activity on 24-month clinical outcomes in patients with knee osteoarthritis

Purpose: Physical activity is well-established as a strong predictor for achieving general health benefits. Despite growing support for increased physical activity prescription in persons with knee osteoarthritis, informed recommendations for reducing sedentary time has received disproportionate attention. The objective of the present study was to quantify the relative contribution of reduced sedentary behaviour (SB) and increased light physical activity (LPA) on clinical knee osteoarthritis progression, in the presence or absence of functional limitations. Methods: Data were extracted from the Osteoarthritis Initiative Accelerometer sub-cohort dataset on 995 participants that had valid wear time data (greater than or equal to 4 days) at baseline (OAI 48-month visit), a Kellgren-Lawrence Grade (KLG) greater than or equal to 2 in one or both knees, and complete self-report measures of pain, joint stiffness and physical function at baseline and 24-month follow-up (OAI 72-month visit). The effect of functional limitation, reduced sedentary time, and increased light physical activity on 24-month clinical worsening was analyzed using multivariate linear models. Sedentary time and light physical activity were categorized into tertiles, and functional limitation was defined as walking <1.2m/sec during a 20-meter walk. The effect of functional limitation and physical activity were estimated in separate models for each tertile that defined clinical worsening using the pain, stiffness and physical function subdomains of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Analyses were adjusted for potential confounders including age, sex, body mass index (BMI), disease severity and previous history of knee injury. Beta coefficients and 95% confidence intervals (CI) were derived for each tertile compared with the reference group (most time spent in sedentary time or least time spent in light activity). Positive and negative beta values correspond to increases (or worsening), and decreases (or improvements), in WOMAC pain, stiffness and physical function, respectively. Results: Approximately 1 in 4 participants (n=295) had functional limitations at baseline. For full description of participant demographics refer to Table 1.View Large Image Figure ViewerDownload Hi-res image Download (PPT) Individuals in the highest tertile of sedentary behaviour had on average 90 minutes less per day of light activity and spent 190 more minutes per day being sedentary compared to the lowest tertile. In participants that did not demonstrate functional limitations at baseline, low time spent in sedentary behaviour and high time spent in light physical activity were associated with improvements in pain (SB adjusted β: -0.74; LPA adjusted β: -3.57) and physical function (SB adjusted β: -1.00; LPA adjusted β: -3.06). However, in participants that did demonstrate functional limitations at baseline, low time spent in sedentary behaviour (adjusted β: -3.82) and high time spent in light activity (adjusted β: -3.14) had the largest average improvements in joint stiffness. Only a moderate amount of time spent in light activity had the largest average improvements in pain (adjusted β: -1.69), yet worse physical function scores (adjusted β: 3.34). Contrary to expectations, the lowest tertile of time spent in sedentary behaviour had an average worsening physical function score of 1.81 (adjusted β), compared to the highest tertile. For changes in 24-month WOMAC subdomain scores between tertiles of sedentary behaviour and functional limitation, refer to Figure 1. Conclusions: Reduced sedentary time compared to increased light physical activity did not demonstrate proportionate effects on long-term clinical outcomes at 24-months. These data propose that the balance between reduced sedentary time, and increased light activity time be considered when prescribing physical activity, and that these recommendations may differ for individuals already demonstrating functional limitations.

Effects of light-activation time on flexural strength of bulk-fill composites

Effects of light-activation time on flexural strength of bulk-fill composites

Relationship of knee pain to time in moderate and light physical activities: Data from Osteoarthritis Initiative.

While OA literature indicates greater pain is related to less time being physically active, it is not known if time curtailment occurs primarily for moderate intensity activities or for light activities or in both. We examine the cross-sectional association of knee pain with physical activity using data from 1874 Osteoarthritis Initiative participants. Knee pain characteristics of constant and intermittent pain were each scored by the Intermittent and Constant Osteoarthritis Pain instrument and categorized into four pain levels (no pain, intermittent pain below and above median level, and constant pain). The relationships between knee pain levels and objectively measured physical activity (average weekly moderate or light intensity minutes) were assessed by quantile regression adjusted for socio-demographics and health factors. Knee pain levels had a strong negative relationship with moderate intensity physical activities (p-value for trend =0.029). Compared to the no pain group, persons with more severe knee pain, particularly those reporting higher intermittent or constant pain spent less time in moderate activity. In contrast, there was no notable trend related to pain with time spent in light intensity activity. These patterns remained when restricted to persons with clinical evidence (symptoms and/or radiographic) of knee OA and among persons not using medications for knee symptoms. Greater knee pain levels were strongly related to less moderate intensity activity time, but not time spent in light intensity physical activity. This relationship suggests that light activity may be a more acceptable way to increase physical activity than moderate activity for people with symptomatic knee pain.

Accelerometer-assessed sedentary work, leisure time and cardio-metabolic biomarkers during one year: Effectiveness of a cluster randomized controlled trial in parents with a sedentary occupation and young children.

BackgroundIt is unknown whether reducing sedentary time at work and during leisure time is possible and effective during one year.MethodsOffice workers with young children were recruited for this one-year cluster-randomized controlled trial through kindergartens and primary schools from 7 clusters in the city of Jyväskylä, Finland. After a lecture, face-to-face tailored counseling was used to set contractually binding goals regarding reducing and breaking up sitting periods and increasing light intensity physical activity during work and leisure time. Primary outcomes of total, work and leisure sedentary time (<100 counts/min, cpm), light activity time (<2020 cpm), moderate-to-vigorous activity time (MVPA) and breaks/sedentary hour were assessed with a waist-worn Alive -accelerometer for 7 days, 5 times during the year. Anthropometrics (DXA), fasting biomarkers and self-reported diet were assessed as secondary outcomes. Data were collected between 2011–2013 and analyzed between 2013–2016 with a linear mixed-effects model fit by REML using likelihood ratio test and intention-to-treat–principle.ResultsParticipants from intervention (N = 71) and control (N = 62) regions were assessed at baseline and 117 completed the study. Sedentary leisure time decreased [-21.2 (95% CI -37.3 to -5.1) min/8 hours, likelihood ratio P<0.001] and light activity time [13.4 (-2.2 to 29.0) min/8 hours, P = 0.008] and breaks per sedentary hour [1.0 (-0.2 to 2.2), P = 0.010] increased in the intervention group as compared to controls at 3 months. The decrease in sedentary leisure time was maintained throughout the year [-7.9 (-24.0 to 8.3) min/8 hours, P = 0.029]. Small decreases in the control group’s work and leisure MVPA were observed mostly at 3 months. Small favorable intervention effects were observed for fasting plasma glucose at 3 months and for leg lean mass and apoB/apoA-1 ratio at 12 months, with no changes in other outcomes.ConclusionsBehavioral counseling induced a small decline in sedentary leisure time throughout one year in parents with a sedentary occupation and young children. Small concurrent changes in different biomarkers suggest that reducing sedentary leisure time during one year may be beneficial.Trial registrationISRCTN28668090, registered 30 November 2011

Effect of major school playground reconstruction on physical activity and sedentary behaviour: Camden active spaces

BackgroundThe physical school environment is a promising setting to increase children’s physical activity although robust evidence is sparse. We examined the effects of major playground reconstruction on physical activity and sedentary time in primary schools using a quasi-experimental design (comparison group pre-test/post-test design).MethodsFive experimental and two control schools from deprived areas of inner city London were recruited at baseline. Main outcome was physical activity and sedentary time measured from objective monitoring (Actigraph accelerometer) at one year follow up. Pupils’ impressions of the new playground were qualitatively assessed post construction.ResultsA total of 347 pupils (mean age = 8 years, 55% boys; 36% Caucasian) were recruited into the study at baseline; 303 provided valid baseline Actigraph data. Of those, 231 (76%) completed follow-up (n = 169 intervention; n = 62 control) and 77.4% of the sample recorded at least 4 days of Actigraph wear. In mixed models adjusted for age, sex, ethnicity, ratio activity or sedentary/wear time at baseline, wear time at follow up, and school, no differences were observed in total moderate – vigorous activity (B = −1.4, 95% CI, −7.1, 4.2 min/d), light activity (B = 4.1, 95% CI, −17.9, 26.1), or sedentary time (B = −3.8, 95% CI, −29.2, 21.6 min/d) between groups. There were significant age interactions for sedentary (p = 0.002) and light intensity physical activity (p = 0.008). We observed significant reductions in total sedentary (−28.0, 95% CI, −1.9, −54.1 min/d, p = 0.037) and increases in total light intensity activity (24.6, 95% CI, 0.3, 48.9 min/d, p = 0.047) for children aged under 9 yrs. old in the intervention.ConclusionMajor playground reconstruction had limited effects on physical activity, but reduced sedentary time was observed in younger children. Qualitative data suggested that the children enjoyed the new playgrounds and experienced a perceived positive change in well-being and social interactions.

Objectively measured physical activity in Brazilians with visual impairment: description and associated factors

Background: Low level of physical activity is a serious health issue in individuals with visual impairment. Few studies have objectively measured physical activity in this population group, particularly outside high-income countries. The aim of this study was to describe physical activity measured by accelerometry and its associated factors in Brazilian adults with visual impairment.Methods: In a cross-sectional design, 90 adults (18–95 years old) answered a questionnaire and wore an accelerometer for at least 3 days (including one weekend day) to measure physical activity (min/day).Results: Sixty percent of the individuals practiced at least 30 min/day of moderate-to-vigorous physical activity. Individuals who were blind were less active, spent more time in sedentary activities and spent less time in moderate and vigorous activities than those with low vision. Individuals who walked mainly without any assistance were more active, spent less time in sedentary activities and spent more time in light and moderate activities than those who walked with a long cane or sighted guide.Conclusion: Our data highlight factors associated with lower levels of physical activity in people with visual impairment. These factors, such as being blind and walking without assistance should be tackled in interventions to increase physical activity levels among visual impairment individuals.Implications for RehabilitationPhysical inactivity worldwide is a serious health issue in people with visual impairments and specialized institutions and public policies must work to increase physical activity level of this population.Those with lower visual acuity and walking with any aid are at a higher risk of having low levels of physical activity.The association between visual response profile, living for less than 11 years with visual impairment and PA levels deserves further investigationsFindings of the present study provide reliable data to support rehabilitation programs, observing the need of taking special attention to the subgroups that are even more likely to be inactive.

201. PHYSICAL ACTIVITY LEVELS IN FEMALE RHEUMATOID ARTHRITIS PATIENTS ON LONG TERM ANTI-TUMOUR NECROSIS FACTOR THERAPY COMPARED TO PATIENTS WITH ACTIVE RHEUMATOID DISEASE AND HEALTHY CONTROLS

Background: Anti-TNF therapy has revolutionised the management of rheumatoid arthritis (RA) with rapid and sustained improvements in pain, function and quality of life. However, we do not know how this impacts upon habitual daily physical activity and whether treated patients attain activity levels seen in healthy controls. This study aimed to compare the physical activity levels of patients whose RA was well controlled on long-term anti-TNF therapy to RA patients with active arthritis and non-RA controls. Methods: Participants were patients on anti-TNF for more than two years (tRA) with DAS 3.2 (aRA) and healthy controls (C), matched for age and BMI. Physical activity was assessed using the Actigraph GT3x+ accelerometer, worn throughout waking hours for seven days to determine time spent in light activity, moderate to vigorous physical activity (MVPA) and sedentary time. The International Physical Activity Questionnaire (IPAQ) was also completed. Groups were compared using analysis of variance with Bonferroni post hoc tests; Kruskal-Wallis or Mann-Whitney U- test as appropriate. Results: RA disease duration was significantly greater in tRA than aRA. Groups did not differ significantly in age, height, weight or body mass index (Table). Daily step count was significantly lower in aRA than tRA and C. Sedentary time (as a proportion of wear time) was significantly greater in aRA than tRA, whilst the reverse was true for light activity time. MVPA time was significantly lower in both RA groups than in controls. IPAQ questionnaires demonstrated significant differences between groups, with substantially higher values in C than RA groups in total METs and MET-minutes per week in domestic and garden, leisure, walking activities as well as total moderate and vigorous activities. RA patients had lower moderate to vigorous activity time than controls, regardless of treatment. aRA had lower light activity time, and more sedentary time, than tRA Conclusion: Moderate to vigorous physical activity should be promoted in all RA patients as even those with well controlled disease exhibit a deficit in comparison to controls

Abstract MP059: Incremental Light Activity Associated with Greater Brain Volume in Individuals Not Meeting the Physical Activity Guidelines: Cross Sectional Observations from the Framingham Heart Study

Background: Recent evidence suggests that dementia appears linked to subclinical vascular changes, which may be attenuated by physical activity. The Physical Activity Guidelines for Americans (PA-Guidelines) are currently set at 150 min of moderate-to-vigorous physical activity (MVPA) per week, as a target for adults to achieve favorable health outcomes, but make no specific recommendations for prevention of dementia. Many Americans fall well below the PA-Guidelines. The aim of this investigation was to determine whether there is a continuum of lower intensities and volumes of physical activity associated with healthy brain aging even in individuals not meeting the PA-Guidelines. Methods: We included Framingham Heart Study (FHS) participants who wore an Actical accelerometer for ≥3 valid days (&gt;10 h wear time per day) on their right hip during the most recent cohort examinations and completed brain magnetic resonance imaging (MRI) an average of 1.7 (±0.9) years later (n=2534): Offspring exam 9, Third Generation exam 2, and corresponding examinations of the Omni cohorts. Participants were excluded from this analysis if they had prevalent stroke or dementia (n=63) or met the 150 min MVPA per week PA-Guidelines (n=1158). Non-wear time (defined as 60 min of zero-counts, with two interruptions allowed) was removed. Sedentary time (&lt;200 counts/min, &lt;1.5 metabolic equivalents [METs]) and light activity (201-1485 counts/min, 1.5-3 METs) were only accumulated during 6 am-10 pm, were represented as proportions of wear time to account for differences in wear time among participants, and standardized to a 16 h day. MVPA (&gt;1486 counts/min, ≥3 METs) and steps were accumulated at any time of day. The relations of physical activity measures to brain MRI measures were assessed using multivariable linear regression. Results: More than 53% of FHS participants did not meet the PA-Guidelines for MVPA during their last exam, and were thus included in this investigation (n=1313, 56 [±14] years old, 60% women). These participants took an average of 6149 [±3079] steps, spent 10.5 [±6.1] min MVPA, 13 h 36 min [±48 min] sedentary and 2 h 14 min [±48 min] in light activities per day. Each additional 40 min of light activity (spent in 1.5-3 METs) or 42 min less time spent sedentary was associated with 0.22% [±0.07%] greater total cerebral brain volume (TCBV), after adjusting for age, sex, body mass index, smoking, diabetes mellitus, and cardiovascular disease (p=0.001), equivalent to approximately 1.1 years less brain aging. Greater light activity and lower sedentary time were also associated with greater hippocampal volume (p&lt;0.005). Conclusions: Our investigation demonstrates, in a community setting, that there may be a negative association of light physical activity with brain aging even among individuals not meeting the PA-Guidelines for MVPA.

Changes in physical activity and sedentary behavior associated with an exercise intervention in depressed adults

BackgroundExercise is beneficial for depression, but less is known about its impact on post-intervention physical activity and sedentary behavior. The aim of this paper was to determine the extent to which participation in light-, moderate- and vigorous-intensity exercise intervention influenced habitual physical activity and sedentary behavior patterns in depressed adults. MethodsAccelerometer data was collected pre- and post-intervention from depressed participants randomized to one of three 12-week intervention groups: light (n = 21), moderate (n = 25) and vigorous (n = 22) exercise. Mixed models examined changes in time spent sedentary and in light and moderate-to-vigorous physical activity (MVPA); time accumulated in sedentary and MVPA bouts; and, number of MVPA bouts and interruptions in sedentary time. ResultsOverall sedentary time decreased while light activity time increased across all intervention groups but not significantly so. The light exercise intervention group reduced MVPA minutes (−8.22, 95% CI: −16.44, −0.01), time in MVPA bouts (−8.44, 95% CI: −14.27, −2.62), and number of activity bouts (−0.43, 95% CI: −0.77, −0.09). The moderate exercise intervention group reduced time in MVPA bouts (−6.27, 95% CI: −11.71, −0.82) and number of sedentary interruptions (−6.07, 95% CI: −9.30, −2.84). No changes were observed for the vigorous exercise intervention group. ConclusionsThe exercise intervention led to an increase in overall light physical activity and decrease in sedentary time, though neither change was statistically significant. Participation in the light and moderate exercise intervention groups was associated with reductions of time in MVPA bouts, but this was not evident for the vigorous exercise intervention group.

Physical Activity Level and Sedentary Behaviors among Public School Children in Dakar (Senegal) Measured by PAQ-C and Accelerometer: Preliminary Results.

Background: Physical inactivity and sedentary lifestyles are major risk factors of childhood obesity. This study aimed to measure physical activity (PA) levels by accelerometer and Physical Activity Questionnaire for Older Children (PAQ-C) among Senegalese school children and the relation with Body Mass Index (BMI) and body composition. Methodology: 156 pupils 8–11 years old were randomly selected in four elementary public schools of Dakar. BMI z-score was used to categorize children according to their weight status. PA was measured by PAQ-C in the 156 pupils and by accelerometer (Actigraph GT3X+, Pensacola, FL, USA) in a subsample of 42 children. Body composition was determined by deuterium dilution method. Results: PAQ-C results were comparable in the 156 and 42 pupils. The 42 pupils presented a light activity measured by accelerometer, while PAQ-C classified the majority of them (57%; n = 24) in the moderate PA level. Children spent most of their time (min/day) in sedentary activities and light activities than in moderate and intense activity levels. Accumulation of 60 min/day Moderate-to-Vigorous Physical Activity (MVPA) was achieved by 54.8% (n = 23) of the pupils. MVPA decreased in girls in relation to their body fatness. There was a significant difference in MVPA between boys and girls. Similarly, overweight/obese (45 ± 16 min/day) children had lower MVPA than their normal and underweight peers (88 ± 34 and 74 ± 36 min/day, respectively; p = 0.004). Conclusions: The two methods are inconsistent for measuring light and moderate PA levels. Although PAQ-C is an uncomplicated routine method, various activities were not adapted for genuine activities in Senegalese children and therefore needs to be validated in African children.

Time and Intensity of Physical Activity During an After-School Jump Rope Program

Childhood obesity has increased significantly in the U.S. over the past two decades. After-school programs can provide opportunities for increasing moderate to vigorous physical activity (MVPA) among children, which could potentially decrease the incidence of obesity. After-school jump rope programs may be one ideal setting to help increase physical activity (PA) among children; however, few studies have evaluated these programs. PURPOSE: The purpose of this study was to examine the amount and intensity of PA students received during an after-school jump rope program. METHODS: Students, ages 8-12 years old, from two elementary schools (n=28) participated in a 12-week after-school jump rope program that met twice a week for 90 minutes each session. Participants practiced individual and group jump rope skills and learned a team routine that they performed at the end of the 12 weeks. Accelerometers were used to assess PA time and intensity and were worn during three session at weeks three, six, and nine. Using the accelerometer counts, intensity cut points were assigned (Freedson et al., 1997). The relationship between PA intensity and gender and minority status was also explored. RESULTS: There was no significant difference between the three accelerometer sessions and data was averaged. In the 90-minutes session, participants spent 17.3 minutes (19.2%) in vigorous activity, 28.0 minutes (31.1%) in moderate activity, 8.0 minutes (8.9%) in light activity, and 36.7 (40.8%) in sedentary behavior. Between groups ANOVA indicated that males (n=7) spent less time in sedentary behavior (p<0.05) and more time in vigorous activity (p<0.01) than females (n=21). Minority participants (n=7) spent less time in sedentary activity (p<0.05) and more time in light (p<0.05) and moderate activity (p<0.001) than non-minority participants (n=21). CONCLUSIONS: Participants received 45.3 minutes of MVPA suggesting that after-school jump rope programs may be an effective venue for helping children achieve the recommended 60 minutes of physical activity per day.

Muscle activity patterns and spinal shrinkage in office workers using a sit–stand workstation versus a sit workstation

Reducing sitting time by means of sit–stand workstations is an emerging trend, but further evidence is needed regarding their health benefits. This cross-sectional study compared work time muscle activity patterns and spinal shrinkage between office workers (aged 24–62, 58.3% female) who used either a sit–stand workstation (Sit–Stand group, n = 10) or a traditional sit workstation (Sit group, n = 14) for at least the past three months. During one typical workday, muscle inactivity and activity from quadriceps and hamstrings were monitored using electromyography shorts, and spinal shrinkage was measured using stadiometry before and after the workday. Compared with the Sit group, the Sit–Stand group had less muscle inactivity time (66.2 ± 17.1% vs. 80.9 ± 6.4%, p = 0.014) and more light muscle activity time (26.1 ± 12.3% vs. 14.9 ± 6.3%, p = 0.019) with no significant difference in spinal shrinkage (5.62 ± 2.75 mm vs. 6.11 ± 2.44 mm). This study provides evidence that working with sit–stand workstations can promote more light muscle activity time and less inactivity without negative effects on spinal shrinkage.Practitioner Summary: This cross-sectional study compared the effects of using a sit–stand workstation to a sit workstation on muscle activity patterns and spinal shrinkage in office workers. It provides evidence that working with a sit–stand workstation can promote more light muscle activity time and less inactivity without negative effects on spinal shrinkage.

Objectively Measured Physical Activity and Symptoms Change in Knee Osteoarthritis

ObjectiveThe study objective was to quantify the association between daily physical activity measured by accelerometer and 1-year changes in symptoms among people with knee osteoarthritis. MethodsParticipants from the Osteoarthritis Initiative had knee radiographs and physical activity assessed using GT1M ActiGraph (Pensacola, FL) uniaxial accelerometers at the 48-month visit. Physical activity was calculated and categorized as tertiles of average daily minutes in light and moderate-to-vigorous activity. Outcomes were 1-year change in symptoms measured by Western Ontario and McMaster Universities scales, including pain, stiffness, and physical function. Adjusted multivariable linear models estimated the relationship between tertiles of light or moderate-to-vigorous physical activity and changes in knee symptoms. ResultsAmong 1059 participants (55% were women; mean age, 66 ± 9 years), greater time in light activity was associated with a trend toward declined physical function (P = .01). Greater time in daily moderate-to-vigorous activity also was associated with declined physical function (P = .01) and increased pain (P = .08). None of these average changes in symptoms reached minimally important clinical differences. However, greater daily time in both activities was associated with a higher probability of worsening symptoms among persons with Kellgren–Lawrence grade 4 osteoarthritis. ConclusionsObjectively measured daily activity was not associated with 1-year symptom improvements among community-dwelling adults with knee osteoarthritis. In those with advanced disease (Kellgren–Lawrence grade 4), greater daily minutes in physical activity were associated with worsening symptoms. How best to implement exercise regimens in persons with advanced knee osteoarthritis to reduce the deleterious impact on symptoms needs to be explored.

Association between maternal education and objectively measured physical activity and sedentary time in adolescents

BackgroundInvestigating socioeconomic variation in physical activity (PA) and sedentary time is important as it may represent a pathway by which socioeconomic position (SEP) leads to ill health. Findings on the...