Comparability of accelerometer- and IPAQ-derived physical activity and sedentary time in South Asian women: A cross-sectional study

Abstract

There is limited research documenting objectively measured physical activity (PA) and sedentary time (ST) in South Asian (SA) women, with no published evidence of the validity of self-report methods for assessment of PA/ST in SA. The purpose of this study was to compare accelerometer- and International Physical Activity Questionnaire (IPAQ)-derived PA/ST among SA women in the United Kingdom (UK) via a mixed-methods approach. One hundred and forty SA women wore an accelerometer for seven consecutive days; a sub-sample (n = 50) completed the IPAQ-Short Form (IPAQ-SF) and a brief structured interview. Accelerometer-derived metabolic equivalent (MET) minutes per week (min/wk) moderate-to-vigorous physical activity (MVPA) (mean ± SD) for the full sample was 793.94 (±519.44) and mean accelerometer-derived ST wk was 530.20 (±81.76). IPAQ-SF-derived MVPA (MET min/wk) was 636.80 (±2113.56) and mean ST wk was 315.31 (±266.98). Pearson correlations were not significant between accelerometer- and IPAQ-SF-assessed MVPA (r = ?.119, p = .579) and ST (r = ?.140, p = .229). Major themes synthesised from interviews included inability to recall sitting time and limited general knowledge of real-life examples of MVPA. These results suggest that the IPAQ-SF may not accurately measure PA/ST in the UK SA women. These findings are supported by qualitative evidence indicating several issues with interpretation and recall of PA/ST as assessed via this questionnaire.     

Environmental correlates of sedentary behaviors and physical activity in Chinese preschool children: A cross-sectional study

ObjectiveThis cross-sectional study examined environmental correlates of sedentary behavior (SB) and physical activity (PA) in preschool children in the urban area of Tianjin, China.MethodsData were collected from the Physical Activity and Health in Tianjin Chinese Children study, involving healthy children 3–6 years old and their families. In all children (n = 980), leisure-time SB (LTSB) and leisure-time PA (LTPA) were reported in min/day by parents. In a subgroup (n = 134), overall sedentary time, light PA, and moderate-to-vigorous PA (MVPA) were objectively measured using ActiGraph accelerometry (≥3 days, ≥10 h/day). Environmental correlates were collected using a questionnaire that included home and neighborhood characteristics (e.g., traffic safety, presence of physical activity facilities) and children's behaviors. Potential correlates were identified using linear regression analysis.ResultsMultiple linear regression analysis showed that “having grandparents as primary caregivers” (βs and 95% confidence intervals (95%CIs) for overall sedentary time: 29.7 (2.1–57.2); LTSB (ln): 0.19 (0.11–0.28)) and “having a television (for LTSB (ln): 0.13 (0.00–0.25)) or computer (for LTSB (ln): 0.13 (0.03–0.23)) in the child's bedroom” were both associated with higher SB. Furthermore, “having grandparents as primary caregivers” was associated with less MVPA (β (95%CI): ?7.6 (?14.1 to ?1.2)), and “active commuting to school by walking” correlated with more MVPA (β (95%CI): 9.8 (2.2–17.4)). The path model showed that “more neighborhood PA facilities close to home” was indirectly related to higher LTPA (ln), which was partly mediated by “outdoor play” (path coefficients (95%CI): 0.005 (0.002–0.008)) and “going to these facilities more often” (path coefficients (95%CI): 0.013 (0.008–0.018)). Traffic safety was not a correlate.ConclusionFamily structure and media exposure in the home maybe important factors in shaping preschoolers’ PA patterns. Built environmental correlates could indirectly influence preschoolers’ LTPA through parental help with engaging in active behaviors.     

Validity and reliability of measures assessing social-cognitive determinants of physical activity in low-active Australian adults

This cross-sectional study of 504 community-dwelling Australian adults (328 females, 176 males, mean age 50.8 ± 13.0 years) sought to examine the reliability and validity of measurement scales for physical activity (PA) self-efficacy and outcome expectations. Participants completed demographic and anthropometric measurements, and a 23-item psychosocial questionnaire pertinent to an intervention target of 10,000 steps per day. Exploratory (n = 252) and confirmatory (n = 252) factor analyses were conducted to determine psychometric properties of the measures. Based on theory and goodness-of-fit indices, six factors were extracted from the questionnaire: PA self-efficacy; PA barriers self-efficacy (including general, personal, and conflict); and physical and mental outcome expectations. From confirmatory factor analysis, the model demonstrated good data fit in four out of five indices: CFI = 0.99; TLI = 0.99; SRMR = 0.03; RMSEA = 0.03, 90%CI = 0.01–0.05, χ² = 113.14 (88), p = 0.04; including good fit by sex, age, weight status, education, and birth country. PA interventions can employ our psychometrically sound social cognitive measures.     

Effects of psychosocial variables in the similarity and interdependence of physical activity levels among adolescent best friend dyads

Given that physical activity (PA) tends to decrease with age during adolescence, addressing factors that affect change is important. This study examined the similarity and interdependence of PA as influenced by psychosocial factors among adolescent best friend dyads. A total of 660 adolescents, representing 330 best friend dyads, completed questionnaires with regard to PA, sitting time, perceived exercise benefits and barriers, physical self-perception and social support for PA. Dyads were also identified as reciprocal and non-reciprocal best friends; reciprocal means that both considered each other best friends and non-reciprocal were those in which only one considered the other a best friend. Data were analysed using a hierarchical linear model framework. Results indicated significant similarities between reciprocal best friend dyads for PA and sitting time, and for sitting time in non-reciprocal best friends (P values <.01). Psychosocial variables were associated with PA in reciprocal best friend dyads and with sitting time in reciprocal and non-reciprocal best friend dyads. Best friend gender, regular sports practice of the person, perceived exercise barriers of the best friend and best friend social support were the best predictors for PA.     

Health-enhancing physical activity and sedentary behaviour in children and adolescents

We provide a wide-ranging review of health-related physical activity in children and adolescents using a behavioural epidemiology framework. In contrast to many other reviews, we highlight issues associated with true sedentary behaviours alongside physically active behaviours. Specifically, we review the evidence concerning the links between physical activity and cardiovascular disease, overweight and obesity, psychosocial measures, type II diabetes, and skeletal health. Although the evidence is unconvincing at times, several factors lead to the conclusion that promoting physical activity in youth is desirable. A review of the prevalence of physical activity and sedentary behaviours shows that many young people are active, but this declines with age. A substantial number are not adequately active for health benefits and current trends in juvenile obesity are a cause for concern. Prevalence data on sedentary behaviours are less extensive but suggest that total media use by young people has not changed greatly in recent years. Most children and adolescents do not exceed recommended daily hours of TV viewing. Physical activity is unrelated to TV viewing. We also identified the key determinants of physical activity in this age group, highlighting demographic, biological, psychological, behavioural, social and environmental determinants. Interventions were considered for school, family and community environments. Finally, policy recommendations are offered for the education, governmental, sport and recreation, health, and mass media sectors.     

Health-enhancing physical activity and sedentary behaviour in children and adolescents

We provide a wide-ranging review of health-related physical activity in children and adolescents using a behavioural epidemiology framework. In contrast to many other reviews, we highlight issues associated with true sedentary behaviours alongside physically active behaviours. Specifically, we review the evidence concerning the links between physical activity and cardiovascular disease, overweight and obesity, psychosocial measures, type II diabetes, and skeletal health. Although the evidence is unconvincing at times, several factors lead to the conclusion that promoting physical activity in youth is desirable. A review of the prevalence of physical activity and sedentary behaviours shows that many young people are active, but this declines with age. A substantial number are not adequately active for health benefits and current trends in juvenile obesity are a cause for concern. Prevalence data on sedentary behaviours are less extensive but suggest that total media use by young people has not changed greatly in recent years. Most children and adolescents do not exceed recommended daily hours of TV viewing. Physical activity is unrelated to TV viewing. We also identified the key determinants of physical activity in this age group, highlighting demographic, biological, psychological, behavioural, social and environmental determinants. Interventions were considered for school, family and community environments. Finally, policy recommendations are offered for the education, governmental, sport and recreation, health, and mass media sectors.     

Associations of accelerometer-measured sedentary time,sedentary bouts,and physical activity with adiposity and fitness in children

ABSTRACT

Sedentary time (ST) has been inconsistently associated with adiposity and cardiorespiratory fitness in children in previous studies. We studied cross-sectional associations of ST, light physical activity (LPA), and moderate-to-vigorous physical activity (MVPA) with fat mass index (FMI) and cardiorespiratory fitness (estimated VO₂max). Associations were evaluated with and without considering pattern of ST by bout length. We measured ST and activity by a wrist-worn accelerometer, FMI by bioelectrical impedance, and VO₂max by Pacer test in 443 children (51.2% girls, 10.2 ± 0.6 years). Isotemporal substitution regression models estimated the effects of substituting ST, LPA, and MVPA on FMI and VO₂max. Further models repeated analyses separating ST into short (<10 min) and long (≥10 min) bouts. Only replacing ST or LPA with MVPA was consistently associated with lower FMI and greater VO₂max. When separated by bout length, only one unique association was found where replacing long ST bouts with short ST bouts was associated with lower FMI in girls only. In conclusion, activity pattern is associated with adiposity in girls and fitness in boys and girls. Separating ST into long and short ST bouts may be of minimal importance when assessing associations with adiposity and fitness using wrist-worn accelerometry in children.     

Calibration of two objective measures of physical activity for children

A calibration study was conducted to determine the threshold counts for two commonly used accelerometers, the ActiGraph and the Actical, to classify activities by intensity in children 5 to 8 years of age. Thirty-three children wore both accelerometers and a COSMED portable metabolic system during 15 min of rest and then performed up to nine different activities for 7 min each, on two separate days in the laboratory. Oxygen consumption was measured on a breath-by-breath basis, and accelerometer data were collected in 15-s epochs. Using receiver operating characteristic curve (ROC) analysis, cutpoints that maximised both sensitivity and specificity were determined for sedentary, moderate and vigorous activities. For both accelerometers, discrimination of sedentary behaviour was almost perfect, with the area under the ROC curve at or exceeding 0.98. For both the ActiGraph and Actical, the discrimination of moderate (0.85 and 0.86, respectively) and vigorous activity (0.83 and 0.86, respectively) was acceptable, but not as precise as for sedentary behaviour. This calibration study, using indirect calorimetry, suggests that the two accelerometers can be used to distinguish differing levels of physical activity intensity as well as inactivity among children 5 to 8 years of age.     

Associations of total sedentary time,screen time and non-screen sedentary time with adiposity and physical fitness in youth: the mediating effect of physical activity

The aims of the present study were: i) to examine the associations of total accelerometer-based sedentary time (ST) and specific-domain self-reported ST (i.e., screen-based, educational-based, social-based, and other-based ST) with adiposity and physical fitness in youth; and ii) to analyse the mediation effect of physical activity (PA) on associations.

This study was conducted with 415 children (9.1 ± 0.4 years) and 853 adolescents (13.6 ± 1.6 years) in Spain during 2011–2012. Total ST and PA were assessed by accelerometry. Leisure-time spent in twelve sedentary behaviours was self-reported. Adiposity and physical fitness was measured following the ALPHA battery for youth.

Total accelerometer-based ST was positively associated with global adiposity score in children, and negatively associated with global physical fitness score in children and adolescents; but relationships were not independent of PA. PA mediated all associations of accelerometer-based and self-reported ST with adiposity or physical fitness in children. Conversely, screen-, educational-, social-, and other-based ST were negatively related to physical fitness in adolescents, independently of PA.

These findings give an impetus to developing effective strategies for specifically promoting PA in children and for increasing PA while reducing ST in adolescents in order to produce improvements on adiposity and physical fitness.     

Associations of subjective social status with accelerometer-based physical activity and sedentary time among adolescents

This study examined the associations of subjective social status (SSS) with physical activity (PA) and sedentary time (ST) among adolescents. The study population consisted of 420 Finnish adolescents aged 13 to 14 years. The adolescents reported their own SSS within their school (school SSS) and their family’s social position within society (society SSS) based on the youth version of the Subjective Social Status Scale. Adolescents’ moderate- to vigorous-intensity physical activity (MVPA) and ST were measured objectively by accelerometers and analyzed separately for the whole day and the school day. The associations between SSS and MVPA and ST outcomes were analyzed using multilevel modeling. School SSS was positively associated with whole-day MVPA and negatively associated with school-time ST. Society SSS was not significantly associated with objectively measured MVPA or ST. Both MVPA and ST are important behavioral determinants of health. As an important correlate of MVPA and ST, school SSS should be addressed by providers when discussing obesity risk and healthy behaviors with adolescents.     

Weekday and weekend patterns of physical activity and sedentary time among Liverpool and Madrid youth

Abstract

Levels of physical inactivity and sedentary behaviour among English and Spanish youth are high and vary within different regions of each country. Little though is known about these during specific periods of the day. The purpose of this study was to describe physical activity (PA) and sedentary time during segments of the day and week, and compare these critical contexts between youth in the Liverpool and Madrid areas of England and Spain, respectively. PA was objectively assessed in 235 Liverpool- and 241 Madrid youth (aged 10–14 years) who wore accelerometers for seven consecutive days. Minutes of sedentary time, moderate PA, vigorous PA and moderate-to-vigorous physical activity (MVPA) were calculated for weekdays, weekend days, school time, non-school time and after-school. Between-country differences were analysed using analysis of covariance (ANCOVA). Madrid youth spent significantly more time in sedentary activities than their Liverpool counterparts. Madrid youth engaged in more minutes of moderate intensity physical activity (MPA) than Liverpool youth during weekdays, school time and non-school time (P<0.01). Liverpool children recorded more time in vigorous physical activity (VPA) than Madrid peers during week days and weekend days (P<0.01) and during school time and after-school periods (P <0.01). The MVPA was significantly higher among Madrid youth during non-school time (P<0.01). Around 25% of all youth achieved recommended levels of MVPA. Low levels of MVPA and systematic differences in sedentary time, MPA and VPA exist between Liverpool and Madrid youth. Interventions targeted at the least-active children during weekends, after-school and non-school periods within the cultural contexts common to each city are required.     

A longitudinal assessment of the links between physical activity and physical self-worth in adolescent females

Abstract

A longitudinal framework was used to examine the hypotheses of (1) whether physical activity predicts changes in physical self-worth or (2) whether physical self-worth predicts changes in physical activity in adolescent girls. Participants (n=272) completed measures of physical self-worth and participation in physical activities at three different points spanning a two-year interval. A cross-lagged panel model using structural equation modelling analyses indicated that physical self-worth predicted subsequent physical activity and physical activity in turn predicted subsequent physical self-worth across time. Findings demonstrated a reciprocal relationship between physical self-worth and physical activity during early adolescence. This study supports the use of the reciprocal effects model (REM) in gaining an understanding of the cross-lagged relationships between physical self-worth and participation in physical activities amongst adolescent girls.     

A systematic review of school-based interventions targeting physical activity and sedentary behaviour among older adolescents

Lack of physical activity (PA) and high levels of sedentary behaviour (SB) have been associated with health problems. This systematic review evaluates the effectiveness of school-based interventions to increase PA and decrease SB among 15–19-year-old adolescents, and examines whether intervention characteristics (intervention length, delivery mode and intervention provider) and intervention content (i.e. behaviour change techniques, BCTs) are related to intervention effectiveness. A systematic search of randomised or cluster randomised controlled trials with outcome measures of PA and/or SB rendered 10 results. Risk of bias was assessed using the Cochrane risk of bias tool. Intervention content was coded using Behaviour Change Technique Taxonomy v1. Seven out of 10 studies reported significant increases in PA. Effects were generally small and short-term (Cohen's d ranged from 0.132 to 0.659). Two out of four studies that measured SB reported significant reductions in SB. Interventions that increased PA included a higher number of BCTs, specific BCTs (e.g., goal setting, action planning and self-monitoring), and were delivered by research staff. Intervention length and mode of delivery were unrelated to effectiveness. More studies are needed that evaluate long-term intervention effectiveness and target SBs among older adolescents.     

Compensatory changes in physical activity and sedentary time in children and adolescents with cystic fibrosis

Physical activity (PA) is a key element in Cystic Fibrosis (CF) treatment strategies, yet little is known as to whether activity compensation occurs. This study examined whether PA and/or sedentary time on one day were temporally associated with time spent in these intensities the following day in youth with CF. Time spent sedentary and in different PA intensities were objectively-measured for seven consecutive days in 50 youth (22 boys; 12.0 ± 2.7 years); 25 with mild-to-moderate CF and 25 age- and sex-matched controls. Multilevel analyses (day and child) were conducted using generalised linear latent and mixed models. On any given day, every additional 10 minutes spent in sedentary time or moderate-to-vigorous physical activity (MVPA) were associated with 1.9 (95%CI: ?3.6 to ?1.2) and 12.4 (95%CI: ?22.1 to ?2.9) minutes less sedentary time the following day, respectively. These temporal associations were also observed when split by group (3.1 vs. 1.9 minutes for healthy and CF, respectively). These findings indicate that youth do not compensate their PA, irrespective of disease status, between days, but may compensate their sedentary time between days. Experimental studies are warranted to fully elucidate whether compensatory responses to PA and sedentary time occur, which is fundamental for informing PA promotion strategies.     

Number of days required for reliably estimating physical activity and sedentary behaviour from accelerometer data in older adults

The purpose of the study was to examine the minimum number of monitoring days for reliably estimating physical activity (PA) and sedentary behaviour (SB) from accelerometer data in older adults. Forty-two older adults from a local senior centre participated in this study. Participants wore an ActiGraph wGT3X-BT on the right hip for 7 consecutive days. Accelerometer data were downloaded to a computer and converted to activity count data in 60s epochs. Time spent in SB and different PA intensity categories were estimated with commonly used activity count cut-points. Participants with at least 7 valid days of monitoring (≥10 h^.day^?1) were included in the analysis. Intraclass correlation coefficients (ICC) were calculated for determining single-day monitoring reliability. The Spearman-Brown prophecy formula was used to estimate the minimum number of monitoring days required for achieving an ICC of 0.80. Single-day ICC values for time spent in SB and PA intensity categories ranged from 0.45 to 0.61. Minimum number of monitoring days required for achieving an ICC of 0.80 ranged from 2.5 to 4.9 days. In this study, a minimum of 5 consecutive days of monitoring was required for reliably estimating SB and PA from accelerometer data in older adults.     

Associations of physical activity,sedentary time,and physical fitness with mental health during pregnancy: The GESTAFIT project

PurposeThis study was aimed to analyze the associations of objectively measured physical activity (PA), sedentary time, and physical fitness with mental health in the early second trimester (16 ± 2 gestational weeks) of pregnancy.MethodsFrom 229 women initially contacted, 124 pregnant women participated in the present cross-sectional study. Data were collected between November 2015 and March 2017. The participants wore Actigraph GT3X+ Triaxial accelerometers for 9 consecutive days to objectively measure their PA levels and sedentary time. A performance-based test battery was used to measure physical fitness. Self-report questionnaires assessed psychological ill-being (i.e., negative affect, anxiety, and depression), and psychological well-being (i.e., emotional intelligence, resilience, and positive affect). Linear regression analyses were adjusted for age, educational level, accelerometer wear time, miscarriages, and low back pain.ResultsModerate-to-vigorous PA was negatively associated with depression (β = –0.222, adjusted R² = 0.050, p = 0.041). Higher levels of sedentary time were negatively associated with positive affect (β = –0.260, adjusted R² = 0.085, p = 0.017). Greater upper-body flexibility was positively associated with better emotional regulation (β = 0.195, adjusted R²= 0.030, p = 0.047). The remaining associations were not significant (all p > 0.05).ConclusionAn active lifestyle characterized by higher levels of moderate-to-vigorous PA and lower levels of sedentary time during pregnancy might modestly improve the mental health of pregnant women. Although previous research has focused on the benefits of cardiorespiratory exercise, the present study shows that only upper-body flexibility is related to emotional regulation in early pregnant women. If the present findings are corroborated in further experimental research, physical exercise programs should focus on enhancing flexibility to promote improvements in emotional regulation during early second-trimester of pregnancy.     

Exploring self-perceptions and social influences as correlates of adolescent leisure-time physical activity

This study examined adolescent leisure-time physical activity correlates using the expectancy-value (EV) model. Adolescents (N = 857) completed questionnaires to assess competence and value self-perceptions, social influences, and physical activity. Direct and indirect effects of self-perceptions and parent and best friend influences on physical activity were explored using structural equation modeling. Measurement models were a good fit to the data and gender invariance was supported. The structural mediation model was a reasonable fit to the data, whereby the indirect effects of parents and peers and the direct effects of competence beliefs and values together accounted for 49% of the variance in physical activity. In this model, the pattern of relationships was similar for adolescent males and females. Findings supporting the EV model provide theoretical and practical implications for understanding adolescent physical activity.     

Using compositional data analysis to explore accumulation of sedentary behavior,physical activity and youth health

Purpose:The study aimed to describe youth time-use compositions,focusing on time spent in shorter and longer bouts of sedentary behavior and physical activity(PA),and to examine associations of these time-use compositions with cardiometabolic biomarkers.Methods:Accelerometer and cardiometabolic biomarker data from 2 Australian studies involving youths 7-13 years old were pooled(complete cases with accelerometry and adiposity marker data,n=782).A 9-component time-use composition was formed using compositional data analysis:time in shorter and longer bouts of sedentary behavior;time in shorter and longer bouts of light-,moderate-,or vigorous-intensity PA;and"other time"(i.e.,non-wear/sleep).Shorter and longer bouts of sedentary time were defined as<5 min and>5 min,respectively.Shorter bouts of light-,moderate-,and vigorous-intensity PA were defined as<1 min;longer bouts were defined as≥1 min.Regression models examined associations between overall time-use composition and cardiometabolic biomarkers.Then,associations were derived between ratios of longer activity patterns relative to shorter activity patterns,and of each intensity level relative to the other intensity levels and"other time",and cardiometabolic biomarkers.Results:Confounder-adjusted models showed that the overall time-use composition was associated with adiposity,blood pressure,lipids,and the summary score.Specifically,more time in longer bouts of light-intensity PA relative to shorter bouts of light-intensity PA was significantly associated with greater body mass index z-score(zBMI)(β=1.79;SE=0.68)and waist circumference(β=18.35,SE=4.78).When each activity intensity was considered relative to all higher intensities and"other time",more time in light-and vigorous-intensity PA,and less time in sedentary behavior and moderate-intensity PA,were associated with lower waist circumference.Conclusion:Accumulating PA,particularly light-intensity PA,in frequent short bursts may be more beneficial for limiting adiposity compared to accumulating the same amount of PA at these intensities in longer bouts.