Moderate-to-vigorous Physical Activity Bouts Research Articles

Fitness Mediates Activity and Sedentary Patterns Associations with Adiposity in Youth.

We aimed to examine the cross-sectional associations of patterns of sedentary time (ST) and moderate-to-vigorous physical activity (MVPA) with total fat mass index (FMI) and abdominal FMI (FMIabd) in children, and additionally, to analyze if cardiorespiratory fitness (CRF) mediated these associations. Fat mass index and FMIabd were assessed with dual-energy X-ray absorptiometry in 333 participants (172 girls) age 9 to 11 yr. MVPA, ST, breaks in ST per sedentary hour (BST/ST) and the number of daily sedentary bouts with various lengths (1-4, 5-9, 10-14, and ≥15 min) were assessed with accelerometry and CRF using a maximal cycle test. Hayes' PROCESS macro for SPSS was used for mediation analysis. The number of shorter sedentary bouts (1-4 min) was inversely associated with FMI (β = -0.108), whereas longer sedentary bouts (5-9 min, β = 0.169; 10-14 min, β = 0.193; ≥15 min, β = 0.377) had a positive association, independent of MVPA (P < 0.05). A similar trend was found for FMIabd. Moderate-to-vigorous physical activity was negatively related to FMI (β = -0.029) and to FMIabd (β = -0.003). There were no main associations for ST and BST/ST (P > 0.05). Cardiorespiratory fitness was inversely related to total and abdominal adiposity, and a large portion (40.9-65.7%) of the associations of MVPA and sedentary bouts with both FMI and FMIabd were mediated by CRF. Time in MVPA and accumulating ST in shorter sedentary bouts is inversely related to adiposity. However, these associations may be mediated by CRF. Emphasis should be given to programs that target increases in MVPA, which may influence CRF while reducing sedentary recreational behaviors.

Incentivizing physical activity using token reinforcement with preschool children.

We combined several single-subject designs to assess the effects of contingent and noncontingent token reinforcement on moderate-to-vigorous physical activity (MVPA) exhibited by 4 preschool-aged children. Higher overall levels and longer bouts of MVPA reliably occurred when tokens were delivered contingent on MVPA for 3 of the 4 children when compared to baseline (no token) and for 2 of the 4 children when compared to noncontingent-token conditions. The present study demonstrated that the delivery of tokens contingent on MVPA can increase and maintain MVPA exhibited by preschool-aged children, resulting in more MVPA than in baseline conditions and conditions in which tokens are awarded without respect to MVPA. These results demonstrate that token economies can be used to increase MVPA and they add to the evidence base supporting the use of token economies to address a range of behavior problems.

Association of Patterns of Moderate-to-Vigorous Physical Activity Bouts With Pain, Physical Fatigue, and Disease Severity in Women With Fibromyalgia: the al-Ándalus Project

ObjectivesTo examine the associations of non-bouted moderate-to-vigorous physical activity (MVPA) and patterns of MVPA in bouts ≥10 minutes with pain, physical fatigue, and disease severity in women with fibromyalgia, and test whether these associations are independent of sedentary time (ST) and physical fitness (PF). DesignCross-sectional study carried out from November 2011 to January 2013. SettingUniversity facilities and fibromyalgia associations. ParticipantsWomen with fibromyalgia (N=439; 51.3±7.6y). InterventionsNot applicable. Main Outcome MeasuresST and MVPA were measured with triaxial accelerometry, and PF with the Senior Fitness test battery. We assessed pain, physical fatigue and disease severity with diverse questionnaires. ResultsTotal time in non-bouted MVPA only was independently associated with lower physical fatigue (B=-0.012; P=.010) and disease severity (B=-0.068; P=.007) in women with fibromyalgia, regardless of PF but not of ST. Patterns of bouted MVPA were overall associated with symptoms independently of ST or PF. The strongest regressor was the maximum time in MVPA bout (min/bout), which was consistently and independently associated with pain, physical fatigue and disease severity after controlling for ST or PF (all, P≤.002). Patients meeting bouted physical activity guidelines displayed lower disease severity than those not meeting guidelines (bouted or non-bouted) and those meeting non-bouted physical activity guidelines (all, P≤.008). ConclusionsPatterns of MVPA performed in bouts ≥10 minutes were overall consistently and independently associated with core symptoms (pain and fatigue) in fibromyalgia and the overall disease severity, regardless of ST or PF. The results suggest that longer bouts of continuous MVPA are associated with better symptoms profile in this population, which needs to be corroborated in longitudinal research.

Physical Activity Patterns and Mortality: The Weekend Warrior and Activity Bouts.

This study aimed to examine how accelerometer-assessed physical activity accumulation patterns (e.g., is activity performed daily or only 1 or 2 d·wk or is activity accrued in bouts) may affect the association with mortality. Adults (N = 3438), age 40 yr and older, who wore an accelerometer (ActiGraph 7164), were drawn from the longitudinal follow-up of the National Health and Nutritional Examination Survey (2003-2006), a population-based survey of the United States. Accelerometer-assessed moderate-to-vigorous physical activity (MVPA) was described by activity patterns. Participants engaging in the majority of their activity on only 1 or 2 d·wk· were classified as "weekend warriors." Activity bouts were defined as a period of at least moderate intensity lasting at least 10 min. Bout characteristics included bout frequency and length. Mortality was assessed through National Death Index matching through 2013. Mortality rates were compared among groups with different activity patterns. Over an average follow-up of 77.4 months, 394 deaths occurred. Compared to participants with <37.5 min of MVPA per week, those with greater amounts of activity had a 60% to 69% mortality rate reduction after adjusting for relevant covariables. Similar risk reductions were found when contrasting weekend warriors with those who were more frequently active. An increase of one MVPA bout per week was associated with a 13% increased mortality rate. Bout duration was not associated with mortality. Physical activity is associated with decreased mortality rate, even among those who are active 1 or 2 d·wk.

The Effect of Physical Activity Bout Patterns on Metabolic Syndrome Risk Factors in Youth: National Health and Nutrition Examination Survey 2003-2006.

Research suggests that accumulating moderate to vigorous physical activity (MVPA) in longer continuous bouts may have beneficial effects on metabolic syndrome risk factors. The objective of this study was to examine the independent associations of MVPA bout patterns on metabolic syndrome risk factors among a nationally representative sample of youth. Results are based on 3165 children and adolescents (6-18y old) from the 2003-2006 National Health and Nutrition Examination Survey. Accelerometers measured MVPA accumulated in bouts of: <5, 5 to 10, and ≥10 minutes over 7 days. Participants were categorized into quartiles based on percentage of each bout duration. Sensitivity analysis was conducted using 3 versions of MVPA cut points for youth. A series of general linear models were used to compare metabolic syndrome risk factors between groups. Youth participating in longer continuous bouts of MVPA had lower body mass index percentile (P < .02), waist circumference (WC) (P < .01), WC percentile (P < .02), and waist to height ratio (P < .01) than youth participating in shorter bouts of MVPA. When analyzed for interactions between MVPA and bout pattern quartile, only 1 cut point showed a significant interaction for WC and WC percentile. Longer continuous bouts of MVPA had beneficial effects on body anthropometrics and weight status, although these effects may be moderated by total MVPA.

Associations of Accumulated Time in Bouts of Sedentary Behavior and Moderate-to-Vigorous Physical Activity With Cardiometabolic Health in 10- to 13-Year-Old Boys.

Little is known about the impact of sedentary and moderate-to-vigorous physical activity (MVPA) bouts on cardiometabolic health. The aim was to examine how the accumulation of bouts of sedentary time and MVPA associates to cardiometabolic health in children independently of total sedentary and MVPA time. In a cross-sectional study with 123 boys (10-13y), sedentary and MVPA bouts were determined using 7-day accelerometry. Each bout was compared with cardiometabolic risk factors and with the risk score that was calculated using standardized values of body mass index, waist circumference, homeostasis model assessment for insulin resistance, triglycerides, and total cholesterol/high-density cholesterol ratio. Time in 10- to 14-minute sedentary bouts was negatively associated with continuous cardiometabolic risk score in weekdays and weekend days and with triglycerides in a weekend (P < .05). Time accumulated in ≥30-minute sedentary bouts was associated with higher insulin and homeostasis model assessment for insulin resistance values in weekend (P < .05). Weekday total MVPA and time accumulated in ≥10-minute MVPA bouts were negatively associated with continuous cardiometabolic risk score and body mass index in weekdays (P < .05). No associations were found between total sedentary time and metabolic health. Significant associations between sedentary and MVPA bouts with cardiometabolic risk factors suggest the need of the more detailed analysis for sedentary behavior and its effects on health risks.

Descriptive epidemiology of accelerometer-measured moderate to vigorous physical activity in Japanese older adults

Most physical activity (PA) guidelines for health promotion recommend moderate to vigorous PA (MVPA) lasting at least 10 minutes (long-bout MVPA). However, recent studies have shown the beneficial effects of short-bout MVPA (intermittent and lasting <10 minutes). Therefore, we aimed to clarify the detailed patterns of MVPA of community-dwelling older adults using accelerometers. This is a cross-sectional descriptive study. Community-dwelling older Japanese adults (total: 1,210; 70-80 years of age) randomly selected from residential registries of 3 municipalities (Bunkyo, Fuchu, and Oyama) were asked to wear an accelerometer (HJA-350 IT; Omron Healthcare, Japan). MVPA was classified by bout length (1-4, 5-9, 10-19, 20-29, and > 30 minutes). The mean frequency and duration of MVPA by each bout length and the proportion of long-bout MVPA were described. Valid data were obtained from 450 participants (men: 56.7%; mean age: 74 years). The mean±standard deviation of the frequency and duration of MVPA bouts were 21.8±14.6 times/day and 2.1±0.9 min, respectively. The total duration of MVPA was 46.5±33.0 min/day. Long-bout MVPA accounted for 26.9%±23.5% of daily MVPA, whereas MVPA of 1-4 minutes accounted for 43.4%. Older adults performed about 45 minutes of MVPA a day, but most of this was short-bout MVPA, which is overlooked by current WHO PA guidelines. In particular, short-bout MVPA was frequent among older women and those living in rural areas.

Short-term and long-term cost-effectiveness of a pedometer-based exercise intervention in primary care: a within-trial analysis and beyond-trial modelling

ObjectivesA short-term and long-term cost-effectiveness analysis (CEA) of two pedometer-based walking interventions compared with usual care.Design(A) Short-term CEA: parallel three-arm cluster randomised trial randomised by household. (B) Long-term CEA: Markov...

Association of objectively measured physical activity and sedentary time with health-related quality of life in women with fibromyalgia: The al-Ándalus project

PurposeTo examine the association of physical activity (PA) intensity levels and sedentary time with health-related quality of life (HRQoL) in women with fibromyalgia and whether patients meeting the current PA guidelines present better HRQoL. MethodsThis cross-sectional study included 407 women with fibromyalgia aged 51.4 ± 7.6 years. The time spent (min/day) in different PA intensity levels (light, moderate, and moderate-to-vigorous physical activity (MVPA) and sedentary time were measured with triaxial accelerometry. The proportion of women meeting the American PA recommendations (≥150 min/week of MVPA in bouts ≥10 min) was also calculated. HRQoL domains (physical function, physical role, bodily pain, general health, vitality, social functioning, emotional role, and mental health), as well as physical and mental components, were assessed using the 36-item Short-Form Health Survey. ResultsAll PA intensity levels were positively correlated with different HRQoL dimensions (rpartial between 0.10 and 0.23, all p < 0.05). MVPA was independently associated with social functioning (p < 0.05). Sedentary time was independently associated with physical function, physical role, bodily pain, vitality, social functioning, and both the physical and mental component summary score (all p < 0.05). Patients meeting the PA recommendations presented better scores for bodily pain (mean = 24.2 (95%CI: 21.3–27.2) vs. mean = 20.4 (95%CI: 18.9–21.9), p = 0.023) and better scores for social functioning (mean = 48.7 (95%CI: 43.9–44.8) vs. mean = 42.3 (95%CI: 39.8–44.8), p = 0.024). ConclusionMVPA (positively) and sedentary time (negatively) are independently associated with HRQoL in women with fibromyalgia. Meeting the current PA recommendations is significantly associated with better scores for bodily pain and social functioning. These results highlight the importance of being physically active and avoiding sedentary behaviors in this population.

A pedometer-based walking intervention in 45- to 75-year-olds, with and without practice nurse support: the PACE-UP three-arm cluster RCT

Guidelines recommend walking to increase moderate to vigorous physical activity (MVPA) for health benefits. To assess the effectiveness, cost-effectiveness and acceptability of a pedometer-based walking intervention in inactive adults, delivered postally or through dedicated practice nurse physical activity (PA) consultations. Parallel three-arm trial, cluster randomised by household. Seven London-based general practices. A total of 11,015 people without PA contraindications, aged 45-75 years, randomly selected from practices, were invited. A total of 6399 people were non-responders, and 548 people self-reporting achieving PA guidelines were excluded. A total of 1023 people from 922 households were randomised to usual care (n = 338), postal intervention (n = 339) or nurse support (n = 346). The recruitment rate was 10% (1023/10,467). A total of 956 participants (93%) provided outcome data. Intervention groups received pedometers, 12-week walking programmes advising participants to gradually add '3000 steps in 30 minutes' most days weekly and PA diaries. The nurse group was offered three dedicated PA consultations. The primary and main secondary outcomes were changes from baseline to 12 months in average daily step counts and time in MVPA (in ≥ 10-minute bouts), respectively, from 7-day accelerometry. Individual resource-use data informed the within-trial economic evaluation and the Markov model for simulating long-term cost-effectiveness. Qualitative evaluations assessed nurse and participant views. A 3-year follow-up was conducted. Baseline average daily step count was 7479 [standard deviation (SD) 2671], average minutes per week in MVPA bouts was 94 minutes (SD 102 minutes) for those randomised. PA increased significantly at 12 months in both intervention groups compared with the control group, with no difference between interventions; additional steps per day were 642 steps [95% confidence interval (CI) 329 to 955 steps] for the postal group and 677 steps (95% CI 365 to 989 steps) for nurse support, and additional MVPA in bouts (minutes per week) was 33 minutes per week (95% CI 17 to 49 minutes per week) for the postal group and 35 minutes per week (95% CI 19 to 51 minutes per week) for nurse support. Intervention groups showed no increase in adverse events. Incremental cost per step was 19p and £3.61 per minute in a ≥ 10-minute MVPA bout for nurse support, whereas the postal group took more steps and cost less than the control group. The postal group had a 50% chance of being cost-effective at a £20,000 per quality-adjusted life-year (QALY) threshold within 1 year and had both lower costs [-£11M (95% CI -£12M to -£10M) per 100,000 population] and more QALYs [759 QALYs gained (95% CI 400 to 1247 QALYs)] than the nurse support and control groups in the long term. Participants and nurses found the interventions acceptable and enjoyable. Three-year follow-up data showed persistent intervention effects (nurse support plus postal vs. control) on steps per day [648 steps (95% CI 272 to 1024 steps)] and MVPA bouts [26 minutes per week (95% CI 8 to 44 minutes per week)]. The 10% recruitment level, with lower levels in Asian and socioeconomically deprived participants, limits the generalisability of the findings. Assessors were unmasked to the group. A primary care pedometer-based walking intervention in 45- to 75-year-olds increased 12-month step counts by around one-tenth, and time in MVPA bouts by around one-third, with similar effects for the nurse support and postal groups, and persistent 3-year effects. The postal intervention provides cost-effective, long-term quality-of-life benefits. A primary care pedometer intervention delivered by post could help address the public health physical inactivity challenge. Exploring different recruitment strategies to increase uptake. Integrating the Pedometer And Consultation Evaluation-UP (PACE-UP) trial with evolving PA monitoring technologies. Current Controlled Trials ISRCTN98538934. This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 22, No. 37. See the NIHR Journals Library website for further project information.

Associations Between Short and Long Bouts of Physical Activity with Executive Function in Older Adults

Greater amounts of moderate-to-vigorous physical activity (MVPA) are frequently associated with better cognitive function in older adults. The 2008 US physical activity guidelines recommended obtaining activity in at least 10-min bouts to achieve health benefits. In the context of brain health, the parameters of MVPA that are necessary to achieve and optimize cognitive benefits are not well understood. Here, we examined whether the association between MVPA and executive function in older adults varied as a function of whether activity was primarily obtained by engaging in MVPA bouts lasting < 10 min compared to engaging in MVPA bouts lasting ≥ 10 min. We collected data on 96 community-dwelling adults aged 55–86 years (mean = 65.77 ± 7.97) without dementia. Executive function was assessed by performance on Stroop and Flanker tasks. MVPA was measured using a multi-sensor SenseWear armband. Consistent with prior literature, after controlling for age, gender, race, body mass index, and time wearing the armband, greater amounts of MVPA were associated with lower Stroop and Flanker interference (all p values ≤ .018). After dividing the MVPA into bouts, we found that MVPA accumulated in bouts of ≥ 10 min was negatively associated with Stroop and Flanker incongruent RT and Stroop interference (all p values ≤ .029). When examining MVPA accumulated in bouts that were < 10 min in duration, we found a negative association with Flanker incongruent condition response time (p = .011). However, in both of these analyses, after controlling for total accumulated minutes of MVPA, only the association between MVPA in bouts of < 10 min was with Flanker incongruent RT (p = .019). These results suggest that total accumulated minutes of MVPA, independent of the duration of the bout, may be most important in relation to cognitive performance in older adults. Our results may have important implications for physical activity recommendations in older adults and support that accumulating MVPA in bouts < 10 min in duration may also have significant cognitive benefits.

Patterns and Levels of Sedentary Behavior and Physical Activity in a General Japanese Population: The Hisayama Study

BackgroundThe purpose of this cross-sectional study was to describe the patterns and levels of sedentary time and physical activity (PA) in a general Japanese population.MethodsA total of 1,740 community-dwelling Japanese adults aged ≥40 years participated in this study. Sedentary time and PA were assessed for 7 consecutive days using a tri-axial accelerometer. Daily patterns and levels of sedentary time and PA were calculated by sex, age group (40–64, 65–74, and ≥75 years), and body mass index (BMI; <25 and ≥25 kg/m2).ResultsParticipants spent half of their waking time being sedentary, 32.7% of which was accumulated in prolonged bouts ≥30 minutes, versus only 54.4 minutes/day (7% of waking time) as moderate-to-vigorous PA (MVPA) (11.8 minutes/day in bouts ≥10 minutes). In addition to total sedentary time, men had longer prolonged sedentary bouts and fewer breaks per sedentary hour than women. Similar trends were observed in participants aged ≥75 years and those with a higher BMI (≥25 kg/m2) compared to those with a younger age and lower BMI. Moreover, participants aged ≥75 years and those with a higher BMI accumulated fewer MVPA minutes in bouts ≥10 minutes. Only 34.8% of the population met the recommended level of ≥150 minutes/week MVPA in bouts ≥10 minutes.ConclusionJapanese adults accumulated a large proportion of total sedentary time in prolonged bouts but few minutes in sustained bouts of MVPA, and few of them met the current PA guideline.

Total volume versus bouts: prospective relationship of physical activity and sedentary time with cardiometabolic risk in children.

Examine the prospective relationship of total volume versus bouts of sedentary behaviour (SB) and moderate-to-vigorous physical activity (MVPA) with cardiometabolic risk in children. In addition, the moderating effects of weight status and MVPA were explored. Longitudinal study including 454 primary school children (mean age 10.3 years). Total volume and bouts (i.e. ≥10 min consecutive minutes) of MVPA and SB were assessed by accelerometry in Nov 2009/Jan 2010 (T1) and Aug/Oct 2010 (T2). Triglycerides, total cholesterol/HDL cholesterol ratio (TC:HDLC ratio), homoeostatic model assessment of insulin resistance, systolic blood pressure and waist circumference were assessed at T2 (Sept/Oct 2010) and combined in a composite cardiometabolic risk score. Associations of total time and uninterrupted MVPA and SB were examined using multilevel mixed linear models, with or without mutual adjustments between MVPA and SB. The moderating effects of weight status and MVPA (for SB only) were examined by adding interaction terms. Children engaged daily in about 60 min of total MVPA and 0-15 min/week in MVPA bouts. Mean total sedentary time was around 7 h/day with over 3 h/day accumulated in bouts. Higher mean levels of MVPA were significantly associated with a lower waist circumference, triglycerides, insulin resistance, TC:HDLC ratio and composite cardiometabolic risk, with non-significant associations for uninterrupted MVPA. Associations with sedentary time were much smaller and inconsistent: higher total sedentary time was associated with higher insulin resistance; after adjusting for MVPA, higher mean total and bouts of sedentary time were associated with lower waist circumference, and sedentary bouts with lower composite cardiometabolic risk. Children accumulated MVPA intermittently and rarely in bouts, and about half their total sedentary time in bouts. Total MVPA is important for lowering cardiometabolic risk in children, whereas both total and uninterrupted sedentary time seem of less importance.

Accelerometer-Derived Activity Phenotypes in Young Adults: a Latent Class Analysis.

To identify "activity phenotypes" from accelerometer-derived activity characteristics among young adults. Participants were young adults (n = 628, mean age, 22.1, SD 0.6) in the Raine Study in Western Australia. Sex-specific latent class analyses identified sub-groups using eight indicators derived from 7-day hip-worn Actigraph GT3X+ accelerometers: daily steps, total daily moderate-to-vigorous physical activity (MVPA), MVPA variation, MVPA intensity, MVPA bout duration, sedentary-to-light ratio, sedentary-to-light ratio variation, and sedentary bout duration. Five activity phenotypes were identified for women (n = 324) and men (n = 304). Activity phenotype 1 for both women (35%) and men (30%) represented average activity characteristics. Phenotype 2 for women (17%) and men (16%) was characterized by below average total activity and MVPA (10.6 and 16.7min of MVPA/day, women and men respectively). Phenotype 3 for women (15%) and men (23%) was characterized by below average total physical activity, average MVPA (32.6 and 36.5min/day), high sedentary-light ratio and long sedentary bouts. Phenotype 4 differed between women (29%) and men (18%) but both had low sedentary-to-light ratios and shorter sedentary bouts. Finally, phenotype 5 in both women (4%) and men (12%) was characterized by extreme MVPA metrics (81.3 and 96.1min/day). Five activity phenotypes were identified for each gender in this population of young adults which can help design targeted interventions to enhance or modulate activity phenotypes.

Pattern of Daily Steps is Associated with Weight Loss: Secondary Analysis from the Step-Up Randomized Trial.

The aim of this study was to examine the association between the amount, intensity, and pattern of steps·day-1 with weight loss. Participants (N = 260; age = 42.8 ± 8.9 y; BMI = 32.8 ± 3.5 kg/m2 ) completed an 18-month weight-loss intervention that included a calorie-restricted diet and prescribed physical activity. Participants were categorized by 18-month weight loss as weight gain (GAIN), weight loss of 0% to < 5% (WL < 5%), 5% to < 10% (WL < 10%), or ≥ 10% (WL ≥ 10%). Steps·day-1 were measured at 0, 6, 12, and 18 months and defined as total steps·day-1 , total steps·day-1 of moderate-to-vigorous physical activity (MVPA) (≥3 metabolic equivalents) in bouts of ≥ 10 minutes (BOUT-MVPA), MVPA in bouts of < 10 minutes (NON-BOUT-MVPA), or non-MVPA steps·day-1 (NON-MVPA). There was a weight-loss category by time interaction (P < 0.0001) for total and BOUT-MVPA steps·day-1 . The total steps·day-1 at 18 months were WL ≥ 10% = 9,822 (95% CI: 9,073-10,571), WL < 10% = 8,612 (7,613-9,610), WL < 5% = 7,802 (6,782-8,822), and GAIN = 7,801 (6,549-9,053). BOUT-MVPA steps·day-1 at 18 months were WL ≥ 10% = 3,482 (2,982-3,981), WL < 10% = 1,949 (1,269-2,629), WL < 5% = 1,735 (1,045-2,426), and GAIN = 1,075 (210-1,941). Participants were also categorized based on achieving ≥ 10% weight loss at either 6 or 18 months, and a similar pattern was observed. These findings show that 10,000 steps·day-1 , with approximately 3,500 steps·day-1 performed as BOUT-MVPA, are associated with enhanced weight loss in a behavioral intervention.

Pattern of physical activity can influence its efficacy on muscle and bone health in middle-aged men and women

PurposeThis study aimed at investigating whether association between physical activity, and bone density and muscle strength depends on daily activity pattern.MethodsLoading dose of moderate-to-vigorous physical activity (MVPA) was measured using accelerometer on 54 men (Mage = 54.1 years) and 59 women (Mage = 52.1 years). Pattern of MVPA was quantified as number and length of MVPA bouts, and the length of break bouts between MVPA bouts. Knee extension torque (KET) and broadband ultrasound attenuation (BUA) of the calcaneus were also measured. Regression analysis was employed to examine the moderation effect of MVPA pattern.ResultsLoading dose had a larger effect on BUA (b = .002, p = .035) and KET (b = .004, p = .01) with the increase of median length of MVPA bout, but had a smaller effect on KET with the increase of maximal length of break bout (b = − .015, p = .024).ConclusionsThis study suggests that pattern of physical activity can influence its efficacy on muscle and bone health.

Physical activity levels in adults and older adults 3-4 years after pedometer-based walking interventions: Long-term follow-up of participants from two randomised controlled trials in UK primary care.

BackgroundPhysical inactivity is an important cause of noncommunicable diseases. Interventions can increase short-term physical activity (PA), but health benefits require maintenance. Few interventions have evaluated PA objectively beyond 12 months. We followed up two pedometer interventions with positive 12-month effects to examine objective PA levels at 3–4 years.Methods and findingsLong-term follow-up of two completed trials: Pedometer And Consultation Evaluation-UP (PACE-UP) 3-arm (postal, nurse support, control) at 3 years and Pedometer Accelerometer Consultation Evaluation-Lift (PACE-Lift) 2-arm (nurse support, control) at 4 years post-baseline. Randomly selected patients from 10 United Kingdom primary care practices were recruited (PACE-UP: 45–75 years, PACE-Lift: 60–75 years). Intervention arms received 12-week walking programmes (pedometer, handbooks, PA diaries) postally (PACE-UP) or with nurse support (PACE-UP, PACE-Lift). Main outcomes were changes in 7-day accelerometer average daily step counts and weekly time in moderate-to-vigorous PA (MVPA) in ≥10-minute bouts in intervention versus control groups, between baseline and 3 years (PACE-UP) and 4 years (PACE-Lift). PACE-UP 3-year follow-up was 67% (681/1,023) (mean age: 59, 64% female), and PACE-Lift 4-year follow-up was 76% (225/298) (mean age: 67, 53% female). PACE-UP 3-year intervention versus control comparisons were as follows: additional steps/day postal +627 (95% CI: 198–1,056), p = 0.004, nurse +670 (95% CI: 237–1,102), p = 0.002; total weekly MVPA in bouts (minutes/week) postal +28 (95% CI: 7–49), p = 0.009, nurse +24 (95% CI: 3–45), p = 0.03. PACE-Lift 4-year intervention versus control comparisons were: +407 (95% CI: −177–992), p = 0.17 steps/day, and +32 (95% CI: 5–60), p = 0.02 minutes/week MVPA in bouts. Neither trial showed sedentary or wear-time differences. Main study limitation was incomplete follow-up; however, results were robust to missing data sensitivity analyses.ConclusionsIntervention participants followed up from both trials demonstrated higher levels of objectively measured PA at 3–4 years than controls, similar to previously reported 12-month trial effects. Pedometer interventions, delivered by post or with nurse support, can help address the public health physical inactivity challenge.Trial registrationsPACE-UP isrctn.com ISRCTN98538934; PACE-Lift isrctn.com ISRCTN42122561.

Physical Activity and Sedentary Patterns among Metabolically Healthy Individuals Living with Obesity.

Background Some individuals living with obesity are free from typical cardiometabolic risk factors and are termed metabolically healthy obese (MHO). The patterns of physical activity and sedentary behaviors among MHO are currently unknown. Methods This study includes 414 youth (12–18 years old), 802 adults (19–44 years old), and 1230 older adults (45–85 years old) living with obesity from the 2003-2004 or 2005-2006 NHANES cycles. Time spent in bouts of 1, 5, 10, 30, and 60 minutes for moderate-to-vigorous physical activity (MVPA) and sedentary time was measured objectively using accelerometers. Participants were categorized as MHO if they had no cardiometabolic risk factors above the identified thresholds (triglycerides, high-density lipoprotein cholesterol, systolic blood pressure, diastolic blood pressure, and glucose). Results The proportion of MHO was 19%, 14%, and 12% in youth, adults, and older adults, respectively. MHO adults displayed a higher 1-minute bout of MVPA per day compared to non-MHO (p = 0.02), but no difference was observed for MVPA and sedentary behavior patterns for youth and older adults. When adjusted for confounders, all bouts of sedentary behavior patterns in youth were significantly associated with being classified as MHO. Conclusion This study suggests that greater sedentary time is associated with cardiometabolic risk factors in youth even if they are physically active.

Latent Profiles of Physical Activity and Sedentary Behavior in Elementary School-Age Youth:Associations With Health-Related Quality of Life.

The objectives were to identify and describe profiles of elementary school-age youth based on objective measurements of total time spent in moderate-to-vigorous physical activity (MVPA) and sedentary behavior (SB) and in bouts of the activities, to examine predictors of profiles, and to examine whether profiles were differentially associated with physical and psychosocial health-related quality of life (HRQOL). Participants included 204 youth (aged 8-11 years) who wore accelerometers to gather objective activity data. The average proportion of time in MVPA and SB and average proportion of time in MVPA and SB bouts were used for analyses. Participants completed a self-report measure of HRQOL. Latent variable mixture modeling was conducted. Overall, participants did not meet the MVPA guideline (M = 50.7 min) and spent 47% of waking hours in SB, indicating that elementary school is a critical developmental period to study activity levels. Three profiles emerged: "Active," "Inactive," and "Moderate." Boys were significantly more likely to be in the Active profile than the other profiles, and older youth were significantly more likely to be in the Inactive profile. After controlling for child sex and age, participants in the Active profile reported significantly higher psychosocial HRQOL than the participants in the other profiles; however, no significant differences were found in physical HRQOL. Identification of these naturally occurring profiles suggests need for interventions early in development focused on increasing the intensity of physical activity from light to moderate-to-vigorous for at least 60 min per day as way to improve psychosocial HRQOL.

Primary care pedometer-based walking intervention: mixed-methods results from 3 year follow-up of PACE-UP cluster-randomised controlled trial

BackgroundMaintenance of physical activity is important for health, but few trials provide long-term objective data or qualitative evaluation of factors affecting this maintenance. The PACE-UP three-arm (postal, nurse-support, control) primary care cluster-randomised controlled trial recruited 1023 adults aged 45–75 years into a 12 week pedometer-based intervention including a physical activity diary and handbook incorporating behaviour change techniques; controls received usual care. Recruitment was from Sept 1, 2012, to Oct 31, 2013. At 12 months, step-counts increased by around a tenth, and time in moderate-to-vigorous physical activity (MVPA) in bouts by around a third in postal and nurse-supported arms compared with control. Using a mixed-methods approach at 3 year follow-up of the PACE-UP cohort, we aimed to assess whether the intervention effects persisted. MethodsAssessments were done between Oct 1, 2015, and Nov 30, 2016. Mean daily step-counts and total weekly minutes of MVPA in bouts of 10 min or more at 3 years were collected with 7 day GT3X+ accelerometry (Actigraph, Pensacola, FL, USA) for all trial arms. Outcomes were regressed on baseline values to estimate change in treatment groups compared with control. Sensitivity analysis assessed missing data effects. Semi-structured telephone interviews were conducted with 60 participants. Interviews were audio recorded, transcribed, and coded, and thematic analysis was performed. Ethics approval was given by the National Research Ethics Service Committee London (Hampstead). Findings3 year follow-up with accelerometry was 67% (681/1023). Compared with controls, intervention groups maintained higher steps per day (postal 627 additional steps[95% CI 198–1056], p=0·004; nurse 670 [237–1102], p=0·002), and more total weekly minutes of MVPA in bouts (postal 28 [7–49], p=0·009; nurse 24 [3–45], p=0·03). Results were robust to sensitivity analyses. Most interviewees felt that PACE-UP had increased their awareness of their physical activity. Facilitators to physical activity maintenance included self-motivation, social-support, and maintaining good health, with poor health and lack of time as barriers. InterpretationAt 3 year follow-up of PACE-UP, step-counts and bouts of MVPA persisted, with no difference between intervention groups, suggesting that a primary care pedometer intervention, delivered by post or with nurse support, could help address the public health physical inactivity challenge. Major future challenges are how to apply this kind of effective intervention widely in the population and how to transform perceived barriers into facilitators (eg, poor physical health). FundingNational Institute for Health Research Health Technology Assessment Programme (project number HTA 10/32/02).