Energy expenditure compared to physical activity measured by accelerometry and self-report in adolescents: a validation study

Associations between device-measured and self-reported physical activity and common mental disorders: Findings from a large-scale prospective cohort study

OBJECTIVES

To investigate the associations between device-measured and self-reported physical activity (PA) and incident common mental disorders in the general population.

DESIGN AND SETTING

Large-scale prospective cohort study.

PARTICIPANTS

Using the UK Biobank data, a validated PA questionnaire was used to estimate self-reported weekly PA in 365 656 participants between 2006 and 2010 while 91 800 participants wore wrist-worn accelerometers for 7 days in 2013-2015 to derive objectively measured PA. All the participants were followed up until 2021.

MAIN OUTCOME MEASURES

Incidences of depression and anxiety were ascertained from hospital inpatient records. Cox proportional hazards models and restricted cubic splines were used to assess the associations between subjectively and objectively measured PA and common mental disorders.

RESULTS

During a median follow-up of 12.6 years, 16 589 cases of depression, 13 905 cases of anxiety and 5408 cases of comorbid depression and anxiety were documented in the questionnaire-based cohort. We found J-shaped associations of self-reported PA with incident risk of depression and anxiety, irrespective of PA intensities. The lowest risk for depression occurred at 550, 390, 180 and 560 min/week of light-intensity PA (LPA), moderate-intensity PA (MPA), vigorous-intensity PA (VPA) and moderate-to-vigorous PA (MVPA), respectively. During a median follow-up of 6.9 years, a total of 2258 cases of depression, 2166 cases of anxiety and 729 cases of comorbid depression and anxiety were documented in the accelerometer-based cohort. We found L-shaped associations of device-measured MPA and VPA with incident depression and anxiety. MPA was adversely associated with incident depression and anxiety until 660 min/week, after which the associations plateaued. The point of inflection for VPA occurred at 50 min/week, beyond which there was a diminished but continued reduction in the risks of depression and anxiety.

CONCLUSION

Different patterns of associations between self-reported and device-measured PA and mental health were observed. Future PA guidelines should fully recognise this inconsistency and increasingly employ objectively measured PA standards.

Total energy expenditure measured by doubly labeled water method in children and adolescents: a systematic review

Total energy expenditure (TEE) is essential for understanding the growth, development, and physical activity of children and adolescents. This study aimed to summarize the existing evidence on TEE measured using the doubly labeled water (DLW) technique in children and adolescents aged 1-18 years. Furthermore, this review compared TEE between obese and normal-weight participants. This systematic review used the PubMed, ScienceDirect, Web of Science, and EBSCO databases. These studies were limited to those published in English between January 2000 and December 2021. Articles presenting objectively measured data on the TEE of children and adolescents aged 1-18 years measured using the DLW method were included. Physical activity level (PAL; TEE/basal metabolic rate [BMR]) and BMR data were also obtained. The search strategy identified 2,351 articles, of which 63 (n=4,283 children and adolescents; 45.4% male) met the selection criteria. The participants in the 10 studies were overweight or obese (n=413). In our study, TEE increased in male and female participants aged 1-18 years. PAL increased with age in males (y=0.0272x+1.3887, r2=0.511) and females (y=0.0199x+1.401, r2=0.335), and the slope of PAL with age did not differ between males and females. The TEE of obese and overweight participants was higher than that of normal-weight participants, but the slope of TEE did not differ between normal-weight (y=132.99x+702.24, r2=0.877) and obese individuals (y=136.18x+1,037.9, r2=0.842). In conclusion, this review provides convincing evidence that daily TEE progressively increases with growth in males and females aged 1-18 years.

The challenges of measuring physical activity and sedentary behaviour in people with rheumatoid arthritis

The importance of sufficient moderate-to-vigorous physical activity as a key component of a healthy lifestyle is well established, as are the health risks associated with high levels of sedentary behaviour. However, many people with RA do not undertake sufficient physical activity and are highly sedentary. To start addressing this, it is important to be able to carry out an adequate assessment of the physical activity levels of individual people in order that adequate steps can be taken to promote and improve healthy lifestyles. Different methods are available to measure different aspects of physical activity in different settings. In controlled laboratory environments, respiratory gas analysis can measure the energy expenditure of different activities accurately. In free-living environments, the doubly labelled water method is the gold standard for identifying total energy expenditure over a prolonged period of time (>10 days). To assess patterns of physical activity and sedentary behaviour in daily life, objective methods with body-worn activity monitors using accelerometry are superior to self-reported questionnaire- or diary-based methods.

Physical Activity, Sedentary Behaviour, Weight Status, and Body Composition among South African Primary Schoolchildren

Background: Over the past decades, childhood overweight has increased in many African countries. We examined the relationship between sedentary behaviour, moderate-to-vigorous physical activity (MVPA), and body composition in South African primary schoolchildren living in peri-urban settings. Methods: MVPA was measured via 7-day accelerometry and body composition via bioelectrical impedance analysis in 1090 learners (49.2% girls, M_age = 8.3 ± 1.4 years). The relationships between MVPA and sedentary behaviour with the various body composition indicators (body fat and fat-free mass [total, truncal, arms, and legs], bone mass, muscle mass, and body water) were tested with mixed linear regressions. Results: The prevalence of overweight and obesity was 9.8% and 6.6%, respectively; 77.1% of the children engaged in ≥60 min of MVPA/day. Girls were more likely to be overweight/obese, to accumulate less than 60 min of MVPA/day, and had significantly higher relative body fat than boys (ps < 0.001). Lower MVPA was associated with a higher likelihood of being overweight/obese, higher relative body fat, and lower relative fat-free mass, bone mass, muscle mass, and body water (ps < 0.001). For lower sedentary behaviour, the associations with body composition pointed in the opposite direction. Conclusions: In this South African setting, girls are a particularly relevant target group for future physical activity interventions to prevent overweight/obesity-related non-communicable diseases in later life.

MicroRNA biogenesis proteins follow tissue-dependent expression during freezing in Dryophytes versicolor

Grey tree frogs (Dryophytes versicolor) have the remarkable ability to endure full-body freezing over the winter, with up to 42% of total body water converted into extracellular ice. Survival is aided by metabolic rate depression that greatly reduces tissue energy costs over the winter. Post-transcriptional controls on gene expression which include miRNA regulation of gene transcripts can aid implementation of the reversible changes required for freeze tolerance, since miRNAs are ideal for facilitating the rapid metabolic reorganization needed for this process. The energy cost for synthesizing new miRNAs is low, and miRNAs' ability to target more than one mRNA transcript (and vice versa) allows a wide versatility in their capability for metabolic restructuring. Western immunoblotting was used to examine protein expression levels of members of the miRNA biogenesis pathway in D. versicolor liver, skeletal muscle, and kidney. Four of these proteins (Dicer, Drosha, Trbp, Xpo5) were upregulated in liver of frozen frogs, suggesting enhanced capacity for miRNA biogenesis, whereas expression of four proteins in frozen muscle (Ago1, Ago2, Dgcr8, Xpo5) and six proteins in kidney (Ago1, Ago2, Ago3, Ago4, Dgcr8, Ran-GTP) were downregulated, indicating an opposite trend. Overall, the data show that miRNA biosynthesis is altered during freezing and differentially regulated across tissues. We suggest that miRNAs are central for the freeze tolerance strategy developed by D. versicolor, and future research will expound upon specific miRNAs and their roles in mediating responses to freezing stress.

Assessment of 24-hour physical behaviour in children and adolescents via wearables: a systematic review of free-living validation studies

Objectives

Studies that assess all three dimensions of the integrative 24-hour physical behaviour (PB) construct, namely, intensity, posture/activity type and biological state, are on the rise. However, reviews on validation studies that cover intensity, posture/activity type and biological state assessed via wearables are missing.

Design

Systematic review. The risk of bias was evaluated by using the QUADAS-2 tool with nine signalling questions separated into four domains (ie, patient selection/study design, index measure, criterion measure, flow and time).

Data sources

Peer-reviewed validation studies from electronic databases as well as backward and forward citation searches (1970–July 2021).

Eligibility criteria for selecting studies

Wearable validation studies with children and adolescents (age <18 years). Required indicators: (1) study protocol must include real-life conditions; (2) validated device outcome must belong to one dimension of the 24-hour PB construct; (3) the study protocol must include a criterion measure; (4) study results must be published in peer-reviewed English language journals.

Results

Out of 13 285 unique search results, 76 articles with 51 different wearables were included and reviewed. Most studies (68.4%) validated an intensity measure outcome such as energy expenditure, but only 15.9% of studies validated biological state outcomes, while 15.8% of studies validated posture/activity type outcomes. We identified six wearables that had been used to validate outcomes from two different dimensions and only two wearables (ie, ActiGraph GT1M and ActiGraph GT3X+) that validated outcomes from all three dimensions. The percentage of studies meeting a given quality criterion ranged from 44.7% to 92.1%. Only 18 studies were classified as ‘low risk’ or ‘some concerns’.

Summary

Validation studies on biological state and posture/activity outcomes are rare in children and adolescents. Most studies did not meet published quality principles. Standardised protocols embedded in a validation framework are needed.

PROSPERO registration number

CRD42021230894.

Association of daily step count and serum testosterone among men in the United States

PURPOSE

To describe the association between daily activity (i.e., daily step counts and accelerometer intensity measures) and serum TT levels in a representative sample of US adults aged 18 years or older.

METHODS

A retrospective cohort study was carried out utilizing the NHANES (National Health and Nutrition Examination Survey) 2003-2004 cycle. Physical activity was measured with a waist-worn uniaxial accelerometer (AM-7164; ActiGraph) for up to 7 days using a standardized protocol. Using linear and multivariable logistic regression controlling for relevant social, demographic, lifestyle, and comorbidity characteristics, we assessed the association between daily step counts and TT.

RESULTS

A total of 279 subjects with a median age 46 (IQR: 33-56) were included in the analysis. 23.3% of the cohort had a low serum TT level (TT < 350 ng/dl). Compared to men who took <4000 steps per day, men who took >4000 or >8000 steps/day had a lower odd of being hypogonadal (OR 0.14, 95% CI: 0.07-0.49 and 0.08, 95%CI: 0.02-0.44, respectively). While a threshold effect was noted on average, TT increased 7 ng/dL for each additional 1000 steps taken daily (β-estimate: 0.007, 95% CI: 0.002-0.013).

CONCLUSIONS

Patients with the lowest daily step counts had higher odds of being hypogonadal. The current work supports a possible association between daily steps, total testosterone, and hypogonadism for men in the US.

Associations of Physical Activity and Sedentary Behaviour Assessed by Accelerometer with Body Composition among Children and Adolescents: A Scoping Review

The possible adverse health effects of reduced physical activity (PA) on children and adolescents have been extensively documented as a result of the global obesity epidemic. However, the research has sometimes led to controversial results, due to the different methods used for the assessment of PA. The main aim of this review was to evaluate the association between PA and body composition parameters based on quantitative PA studies using the same equipment (Actigraph accelerometer) and cutoffs (Evenson’s). A literature review was undertaken using PUBMED and Scopus databases. Subjects aged 6–15 were considered separately by sex. Weighted multiple regression analyses were conducted. From the analysis of fourteen selected articles, it emerged that 35.7% did not evaluate the association of sedentary time (ST) and moderate-to-vigorous physical activity (MVPA) with body composition, while the remaining 64.3% found a negative association of MVPA with BMI and fat mass with different trends according to sex. Furthermore, only 7.1% of these studies identified a positive association between ST and fat percentage. Based on the regression analyses conducted on the literature data, ST and MVPA were found to be significant predictors of body composition parameters, in addition to age and sex. Further studies using standardized methodologies to assess PA and body composition are needed. The inclusion of sex-disaggregated data may also be crucial to understand this phenomenon and to provide stronger evidence of the determinants of body composition in order to prevent the risk of obesity.

Compliance of the Physical Activity Guidelines Accumulated in Bouts ≥10 Min and Nonbouts and Its Association With Body Composition and Physical Function: A Cross-Sectional Study in Brazilian Older Adults

This study aimed to investigate the association between compliance with the guidelines of moderate to vigorous physical activity (MVPA) accumulated in bouts of ≥10 min or nonbouts with body composition and physical function in older adults. The authors evaluated 230 noninstitutionalized older adults. Body composition was estimated using bioimpedance, and physical function was assessed using four physical tests. Physical activities were monitored for 7 days using an accelerometer. Older adults who were physically active according to MVPA in bouts of ≥10 min were less likely to have low appendicular skeletal muscle mass (odds ratio [OR] = 0.12), excess body fat (OR = 0.30), and abdominal obesity (OR = 0.34) and more likely to have a higher physical function (OR = 5.78). No significant association was observed with MVPA nonbout. Our findings indicate that older adults who accumulate MVPA in bouts of  ≥10 min have better parameters for body composition and physical function.

Intracellular and tissue specific expression of FTO protein in pig: changes with age, energy intake and metabolic status

Genome-wide association studies in the FTO gene have identified SNPs correlating with obesity and type 2 diabetes. In mice, lack of Fto function leads to intrauterine growth retardation and lean phenotype, whereas in human it is lethal. The aim of this study in a pig model was to determine the localization of the FTO protein in different tissues and cell compartments, in order to investigate potential targets of FTO action. To better understand physiological role of FTO protein, its expression was studied in pigs of different age, metabolic status and nutrition, using both microscopic methods and Western blot analysis. For the first time, FTO protein was found in vivo in the cytoplasm, of not all, but specific tissues and cells e.g. in the pancreatic β-cells. Abundant FTO protein expression was found in the cerebellum, salivary gland and kidney of adult pigs. No FTO protein expression was detected in blood, saliva, and bile, excluding its role in cell-to-cell communication. In the pancreas, FTO protein expression was positively associated with energy intake, whereas in the muscles it was strictly age-related. In IUGR piglets, FTO protein expression was much higher in the cerebellum and kidneys, as compared to normal birth body weight littermates. In conclusion, our data suggest that FTO protein may play a number of distinct, yet unknown intracellular functions due to its localization. Moreover, it may play a role in animal growth/development and metabolic state, although additional studies are necessary to clarify the detailed mechanism(s) of action.

Critical evaluation of physical activity questionnaires translated to Brazilian-Portuguese: a systematic review on cross-cultural adaptation and measurements properties

BACKGROUND

The number of questionnaires that measures physical activity levels has increased considerably. For Brazilian population it becomes a challenge, due to the need of a rigorous translation, adaptation and testing of measurement properties.

OBJECTIVE

Evaluate the methodological quality and criteria of physical activity questionnaires translated to Brazilian-Portuguese.

METHODS

Methodological quality and quality criteria was assessed using the COnsensus-based Standards for the selection of health Measurement INstruments checklist.

RESULTS

Sixty-nine studies were included, the most frequent questionnaires investigated were the International Physical Activity Questionnaire (n=16) and the Baecke Physical Activity Questionnaire (n=12). Translation (n=13), reliability (n=37) and construct validity (n=44) were the measurement properties commonly investigated. For reliability, most studies were rated as 'adequate' for methodological quality. The Intraclass Correlation Coefficient of the questionnaires ranged from 0.20 to 1.0. For construct validity, 31 analyses showed 'inadequate' methodological quality, due to poor description of the comparator instrument. High level of evidence on reliability were found for Baecke Physical Activity Questionnaire, Self-administered Physical Activity Checklist and Physical Activity Questionnaire of the Surveillance System of Risk Factors and Protection for Chronic Diseases; on construct validity for Self-administered Physical Activity Checklist, Physical activity Questionnaire for Adolescents, Physical activity Questionnaire for Older Children and Saúde naBoa Questionnaire.

CONCLUSION

Most questionnaires showed poor methodological quality and measurement properties. The Baecke Physical Activity Questionnaire and Self-administred Physical Activity Checklist showed better scorings for methodological quality and quality criteria. Further high methodological quality studies are still warranted.

Evaluation of the exercise intensity generated by active video gaming in patients with cystic fibrosis and healthy individuals

BACKGROUND

Adherence of patients with cystic fibrosis (CF) to exercise is challenging. Here we compared the physiological responses during the use of interactive video games (VG) with the cardiopulmonary exercise test (CPET) in healthy and CF subjects.

METHODS

Cross-sectional study including CF and healthy (CON) subjects older than 6 years. Individuals were evaluated in two visits. At visit one, anthropometric measures, spirometry and CPET were performed. In the second visit, a physical activity questionnaire was applied and gas analyses performed during the use (10 min) of both Nintendo Wii (Wii Fit Plus: (1) Obstacle Course, (2) Rhythm Boxing and (3) Free Run) and Xbox One (Just Dance 2015: (1) Love Me Again, (2) Summer and (3) Happy).

RESULTS

Twenty-five CON and 30 CF patients were included. The mean FEV₁ (%) was significantly lower in the CF group compared to CON. There were no differences between groups at peak exercise (CPET) for heart rate (HR), oxygen consumption (VO₂) and minute ventilation (V_E). In the CON group, games 2 and 3 (Xbox) and game 3 (Nintendo) increased HR to values similar to the anaerobic threshold (AT), while for the CF group this occurred for games 2 (Xbox) and 3 (Nintendo). As for VO₂ and V_E, both groups obtained similar responses as compared to AT values in games 2 (Xbox) and 3 (Nintendo).

CONCLUSION

The use of VG generated a cardiorespiratory response similar to AT levels found during CPET, indicating that it may be an alternative for exercise training of CF individuals.

Accelerometer-determined physical activity and cognitive function in middle-aged and older adults from two generations of the Framingham Heart Study

INTRODUCTION

Physical activity (PA) may play a role in maintenance of cognitive function in both middle and older ages and prevention of outcomes such as dementia and Alzheimer's disease.

METHODS

Cross-sectional regression analyses were performed in Framingham Heart Study Third Generation (n = 1861) and Offspring (n = 909) cohort participants assessing the association of accelerometry-measured PA with cognitive function, adjusting for age, sex, accelerometer wear time, education, occupational status/PA, and smoking status.

RESULTS

In each cohort, achieving just 10-21.4 min/day moderate-to-vigorous PA related to better executive function (P < .02); and just 10 min/day moderate-to-vigorous PA was associated with better verbal memory in middle-aged adults in the Third Generation cohort (P = .02). In older adults of the Offspring cohort, total PA (measured in steps/day) was associated with better executive function (P < .02).

DISCUSSION

PA at levels lower than the current PA Guidelines (just 10 min/day moderate-to-vigorous PA and total PA including lower intensity PA) were associated with better cognitive function.

An Updated Systematic Review of Childhood Physical Activity Questionnaires

Background and Objective

This review is an update of a previous review published in 2010, and aims to summarize the available studies on the measurement properties of physical activity questionnaires for young people under the age of 18 years.

Methods

Systematic literature searches were carried out using the online PubMed, EMBASE, and SPORTDiscus databases up to 2018. Articles had to evaluate at least one of the measurement properties of a questionnaire measuring at least the duration or frequency of children’s physical activity, and be published in the English language. The standardized COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) checklist was used for the quality assessment of the studies.

Results

This review yielded 87 articles on 89 different questionnaires. Within the 87 articles, 162 studies were conducted: 103 studies assessed construct validity, 50 assessed test–retest reliability, and nine assessed measurement error. Of these studies, 38% were of poor methodological quality and 49% of fair methodological quality. A questionnaire with acceptable validity was found only for adolescents, i.e., the Greek version of the 3-Day Physical Activity Record. Questionnaires with acceptable test–retest reliability were found in all age categories, i.e., preschoolers, children, and adolescents.

Conclusion

Unfortunately, no questionnaires were identified with conclusive evidence for both acceptable validity and reliability, partly due to the low methodological quality of the studies. This evidence is urgently needed, as current research and practice are using physical activity questionnaires of unknown validity and reliability. Therefore, recommendations for high-quality studies on measurement properties of physical activity questionnaires were formulated in the discussion.

PROSPERO Registration Number

CRD42016038695.

Electronic supplementary material

The online version of this article (10.1007/s40279-018-0987-0) contains supplementary material, which is available to authorized users.

Physical Activity Level Using Doubly-Labeled Water in Relation to Body Composition and Physical Fitness in Preschoolers

Background and objectives: There is a lack of studies investigating associations of physical activity level (PAL) and activity energy expenditure (AEE) using the doubly-labeled water (DLW) method with body composition and physical fitness in young children. Thus, we aimed to examine cross-sectional associations of PAL and AEE with body composition indices and physical fitness components in Swedish preschool children. Materials and methods: PAL was calculated as total energy expenditure measured using DLW divided by the predicted basal metabolic rate in 40 children aged 5.5 (standard deviation 0.2) years. AEE was calculated as total energy expenditure minus basal metabolic rate and the thermic effect of food, and divided by fat-free mass. Body composition was assessed using the 3-component model by combining measurements based on isotope dilution and air-displacement plethysmography. Physical fitness (muscular strength, motor fitness, and cardiorespiratory fitness) was evaluated using the PREFIT test battery. Multiple linear regression models were conducted. Results: PAL and AEE were negatively associated with body mass index, percent body fat, and fat mass index (PAL: standardized β −0.35, −0.41, and −0.45, all p < 0.036; AEE: standardized β −0.44, −0.44, and −0.47, all p < 0.006, respectively). Furthermore, PAL and AEE were positively associated with the standing long jump test (PAL: standardized β 0.37, p = 0.017; AEE: standardized β 0.38, p = 0.014). There were no statistically significant associations found regarding PAL or AEE with fat-free mass index or any other physical fitness test. Conclusions: Greater PAL and AEE at the age 5.5 were significantly associated with body fatness and improved lower-body muscular strength. Therefore, increasing physical activity, and thus energy expenditure, at young ages may be beneficial for preventing overweight/obesity. However, further studies with larger sample sizes are needed to confirm the results.

Reliability and Validity of a Questionnaire for Physical Activity Assessment in South American Children and Adolescents: The SAYCARE Study

OBJECTIVE

The objective of this article is to test the reliability and validity of the new and innovative physical activity (PA) questionnaire.

METHODS

Subsamples from the South American Youth/Child Cardiovascular and Environment Study (SAYCARE) study were included to examine its reliability (children: n = 161; adolescents: n = 177) and validity (children: n = 82; adolescents: n = 60). The questionnaire consists of three dimensions of PA (leisure, active commuting, and school) performed during the last week. To assess its validity, the subjects wore accelerometers for at least 3 days and 8 h/d (at least one weekend day). The reliability was analyzed by correlation coefficients. In addition, Bland-Altman analysis and a multilevel regression were applied to estimate the measurement bias, limits of agreement, and influence of contextual variables.

RESULTS

In children, the questionnaire showed consistent reliability (ρ = 0.56) and moderate validity (ρ = 0.46), and the contextual variable variance explained 43.0% with -22.9 min/d bias. In adolescents, the reliability was higher (ρ = 0.76) and the validity was almost excellent (ρ = 0.88), with 66.7% of the variance explained by city level with 16.0 min/d PA bias.

CONCLUSIONS

The SAYCARE PA questionnaire shows acceptable (in children) to strong (in adolescents) reliability and strong validity in the measurement of PA in the pediatric population from low- to middle-income countries.

The effects of interrupting prolonged sitting with intermittent activity on appetite sensations and subsequent food intake in preadolescent children

Background

Short-term and long-term exposure to prolonged sitting is associated with excess food intake and weight gain in children. Interrupting prolonged sitting with low-intensity activity has been shown to not alter hunger, satiety, or food consumption in children, however it is unclear whether interrupting sitting with high-intensity activity will alter appetite regulation in children.

Purpose

The purpose of this study was to examine the acute effects of interrupting prolonged sitting with intermittent activity performed at varying intensities on hunger, satiety, prospective food consumption (PFC), and food intake in preadolescent children.

Methods

Thirty-nine children (ages 7–11 years, 54% female, 33% overweight/obese) completed four experimental conditions in random order: 8 hours of sitting interrupted with 20, 2-minute low-, moderate-, or high-intensity activity breaks or 20, 2-minute sedentary screen time breaks. Exercise intensity corresponded with 25%, 50% and 75% of heart rate reserve, respectively. Hunger, satiety, and PFC were assessed using the Visual Analog Scale, at five time points (pre- and post-breakfast, pre- and post-lunch, and pre-dinner) during each experimental condition. Dietary compensation was assessed as total caloric intake during a post-condition dinner standardized to provide 70% of estimated daily energy requirements.

Results

There was a significant effect of time on hunger, satiety, and PFC throughout each condition day (p< 0.001). There were no differences across conditions for hunger (sedentary: 4.9±0.3 cm, low: 5.0±0.3 cm, moderate: 5.1±0.3 cm, high: 5.1±0.3 cm, p>0.05), satiety (sedentary: 4.7±0.3 cm, low: 4.4±0.3 cm, moderate: 4.6±0.3 cm, high: 4.2±0.3 cm, p>0.05), and PFC (sedentary: 4.9±0.3 cm, low: 4.7±0.3 cm, moderate: 4.9±0.3 cm, high: 5.0±0.3 cm, p>0.05). There were no significant differences in post-activity food intake across conditions (sedentary: 1071.9±53.6 kcals; low: 1092.6±43.4kcals; moderate: 996.2±54.6kcals; high: 1138.7±62.8kcals, p>0.05). However, there was a significant effect of condition on energy balance (sedentary: +61.4±65.9 kcals, low: +74.9±57.6 kcals, moderate: -58.3±62.8 kcals, high: -391.2±77.9 kcals; p<0.001). There were no significant effects of weight status on hunger, satiety, PFC, post-activity food intake, and mean energy balance across conditions (all p’s>0.05).

Conclusions

Interrupting prolonged sitting with physical activity of any intensity does not alter appetite sensations and subsequent food consumption in children. These data suggest that interventions targeting prolonged sitting with high-intensity intermittent activity may be an effective strategy to increase physical activity energy expenditure without increasing food intake, allowing for a short-term energy deficit in both healthy weight and overweight/obese children. Future studies should examine the long-term effects of interrupting prolonged sitting with activity on food consumption and weight status in preadolescent children.

Understanding Environmental and Contextual Influences of Physical Activity During First-Year University: The Feasibility of Using Ecological Momentary Assessment in the MovingU Study

BACKGROUND

It is well established that drastic declines in physical activity (PA) occur during young adults' transition into university; however, our understanding of contextual and environmental factors as it relates to young adults' PA is limited.

OBJECTIVE

The purpose of our study was to examine the feasibility of using wrist-worn accelerometers and the use of ecological momentary assessment (EMA) to assess the context and momentary correlates of PA on multiple occasions each day during first-year university.

METHODS

First-year university students were asked to participate in the study. The participants completed a brief questionnaire and were subsequently asked to wear an ActiGraph GT9X-Link accelerometer and respond to a series of EMA prompts (7/day) via their phones for 5 consecutive days.

RESULTS

A total of 96 first-year university students with smartphones agreed to participate in the study (mean age 18.3 [SD 0.51]; n=45 females). Overall, there was good compliance for wearing the accelerometers, with 91% (78/86) of the participants having ≥2 days of ≥10 hours of wear time (mean=3.53 valid days). Students were generally active, averaging 10,895 steps/day (SD 3413) or 1123.23 activity counts/min (SD 356.10). Compliance to EMA prompts was less desirable, with 64% (55/86) of the participants having usable EMA data (responding to a minimum of ≥3 days of 3 prompts/day or ≥4 days of 2 prompts/day), and only 47% (26/55) of these participants were considered to have excellent EMA compliance (responding to ≥5 days of 4 prompts/day or ≥ 4 days of 5 prompts/day).

CONCLUSIONS

This study represents one of the first studies to use an intensive real-time data capture strategy to examine time-varying correlates of PA among first-year university students. These data will aim to describe the physical and social contexts in which PA occurs and examine the relationships between momentary correlates of PA among the first-year university students. Overall, current results suggest that wrist-worn accelerometers and EMA are feasible methods for data collection among the young adult population; however, more work is needed to understand how to improve upon compliance to a real-time data capture method such as EMA.

Associations of objective physical activity with insulin sensitivity and circulating adipokine profile: the Framingham Heart Study

The purpose of this study was to explore the relation of physical activity (PA) and sedentary time (SED) to insulin sensitivity and adipokines. We assessed PA and SED using Actical accelerometers and insulin resistance (HOMA-IR) in 2109 participants (free of type 1 and 2 diabetes mellitus) from Framingham Generation 3 and Omni 2 cohorts (mean age 46 years, 54% women). Systemic inflammation (C-reactive protein [CRP]) and circulating adipokines were measured 6 years earlier. Steps per day, moderate-to-vigorous PA (MVPA) and SED per wear time (%SED) were predictor variables in multivariable regression analyses, with HOMA-IR, CRP and circulating adipokines as outcome measures. We reported that higher MVPA and more steps per day were associated with lower HOMA-IR, adjusting for %SED (β = -0.036, P = 0.002; β = -0.041, P = 0.005). Steps were inversely associated with CRP, but were directly associated with insulin-like growth factor (IGF)-1 levels (β = -0.111, P = 0.002; β = 3.293, P = 0.007). %SED was positively associated with HOMA-IR (β = 0.033, P < 0.0001), but non-significant after adjusting for MVPA (P = 0.13). %SED was associated with higher ratio of leptin/leptin receptor (sOB-R) and higher adipocyte fatty acid-binding protein (FABP)4 (β = 0.096, P < 0.0001; β = 0.593, P = 0.002). Our findings suggest differential influences of PA vs. SED on metabolic pathways, with PA modulating insulin resistance and inflammation, whereas SED influences FABPs.

Feasibility and Performance Test of a Real-Time Sensor-Informed Context-Sensitive Ecological Momentary Assessment to Capture Physical Activity

Background

Objective physical activity monitors (eg, accelerometers) have high rates of nonwear and do not provide contextual information about behavior.

Objective

This study tested performance and value of a mobile phone app that combined objective and real-time self-report methods to measure physical activity using sensor-informed context-sensitive ecological momentary assessment (CS-EMA).

Methods

The app was programmed to prompt CS-EMA surveys immediately after 3 types of events detected by the mobile phone’s built-in motion sensor: (1) Activity (ie, mobile phone movement), (2) No-Activity (ie, mobile phone nonmovement), and (3) No-Data (ie, mobile phone or app powered off). In addition, the app triggered random (ie, signal-contingent) ecological momentary assessment (R-EMA) prompts (up to 7 per day). A sample of 39 ethnically diverse high school students in the United States (aged 14-18, 54% female) tested the app over 14 continuous days during nonschool time. Both CS-EMA and R-EMA prompts assessed activity type (eg, reading or doing homework, eating or drinking, sports or exercising) and contextual characteristics of the activity (eg, location, social company, purpose). Activity was also measured with a waist-worn Actigraph accelerometer.

Results

The average CS-EMA + R-EMA prompt compliance and survey completion rates were 80.5% and 98.5%, respectively. More moderate-to-vigorous intensity physical activity was recorded by the waist-worn accelerometer in the 30 minutes before CS-EMA activity prompts (M=5.84 minutes) than CS-EMA No-Activity (M=1.11 minutes) and CS-EMA No-Data (M=0.76 minute) prompts (P’s<.001). Participants were almost 5 times as likely to report going somewhere (ie, active or motorized transit) in the 30 minutes before CS-EMA Activity than R-EMA prompts (odds ratio=4.91, 95% confidence interval=2.16-11.12).

Conclusions

Mobile phone apps using motion sensor–informed CS-EMA are acceptable among high school students and may be used to augment objective physical activity data collected from traditional waist-worn accelerometers.

Inspiratory muscle function in asthmatic and healthy subjects: influence of age, nutrition and physical activity

OBJECTIVE

To compare inspiratory muscle function (strength and endurance) between asthmatics and healthy controls, and the influence of age, nutritional status and physical activity on them.

METHODS

This is a cross-sectional study. Asthmatic and healthy subjects, aged 6 to 18 years old, recruited from two public schools in Southern Brazil were included in the study. Asthmatic subjects were selected using the criteria presented by the International Study on Asthma and Allergies in Children and control subjects based on the absence of respiratory symptoms. Anthropometric data was measured, body mass index calculated and subjects classified as normal weight, overweight or obese. Physical activity levels, maximum inspiratory pressure (MIP) and inspiratory muscle endurance (IME) were also evaluated.

RESULTS

A total of 314 participants were included, separated into control group (181) and asthmatics (133), with a total mean age of 11 years. When both groups were compared, there were no significant differences in both MIP and IME. However, when groups were analyzed subdivided in children and adolescents, IME was significantly reduced (p = 0.003) in asthmatic adolescents. Indeed, when groups were also stratified considering the nutritional status, IME showed a reduction in asthmatic adolescents with overweight (p = 0.042) and obesity (p = 0.041) when compared to healthy controls. No effects of physical activity levels between groups were found.

CONCLUSIONS

Results demonstrate a reduction in the IME in asthmatic adolescents with overweight and obesity, indicating an association between asthma, nutritional status and respiratory muscle function.

[Physical inactivity and anthropometric measures in school children from Paranavaí, Paraná, Brazil]

OBJECTIVE

To investigate the association between physical inactivity and anthropometric measurements in school children from Paranavaí-Paraná, Brazil.

METHODS

Cross-sectional survey, conducted in July and August 2013. Sample of 566 students (287 boys and 278 girls) from 6th to 9th grade aged 10 to 14 years of public and private schools from Paranavaí-PR, Southern Brazil. The variables analyzed were: time of weekly physical activity by a questionnaire (physical inactivity <300 minutes/week), body mass index (BMI) and waist circumference (WC). In the statistical analysis the U Mann-Whitney and Student t test were used for comparison between genders. To identify factors associated with insufficient levels of physical activity, univariate and multivariate logistic regression analysis was applied and expressed in Odds ratio (OR) and 95% confidence interval (CI).

RESULTS

There was an association between physical inactivity and anthropometric measurements for BMI (p<0.001) and WC (p<0.001), with a prevalence rate of 56.1% and 52.7% of inactive adolescents, respectively. In the multivariate analysis, there was significant association of physical inactivity and overweight (OR 1.8, 95%CI: 1.1-3.0) and with increased waist circumference (OR 2.8, 95%CI: 1.4-3.8).

CONCLUSIONS

Inadequate levels of physical activity is a determining factor for overweight and abdominal adiposity. Accordingly, preventive measures should be taken, especially in schools, emphasizing the importance of exercise in the control of body composition and reduction of weight.

Web-based assessments of physical activity in youth: considerations for design and scale calibration

This paper describes the design and methods involved in calibrating a Web-based self-report instrument to estimate physical activity behavior. The limitations of self-report measures are well known, but calibration methods enable the reported information to be equated to estimates obtained from objective data. This paper summarizes design considerations for effective development and calibration of physical activity self-report measures. Each of the design considerations is put into context and followed by a practical application based on our ongoing calibration research with a promising online self-report tool called the Youth Activity Profile (YAP).

We first describe the overall concept of calibration and how this influences the selection of appropriate self-report tools for this population. We point out the advantages and disadvantages of different monitoring devices since the choice of the criterion measure and the strategies used to minimize error in the measure can dramatically improve the quality of the data. We summarize strategies to ensure quality control in data collection and discuss analytical considerations involved in group- vs individual-level inference. For cross-validation procedures, we describe the advantages of equivalence testing procedures that directly test and quantify agreement. Lastly, we introduce the unique challenges encountered when transitioning from paper to a Web-based tool. The Web offers considerable potential for broad adoption but an iterative calibration approach focused on continued refinement is needed to ensure that estimates are generalizable across individuals, regions, seasons and countries.

Follow-up of a healthy lifestyle education program (the Educació en Alimentació Study): 2 years after cessation of intervention

PURPOSE

The Educació en Alimentació (EdAl) program conducted over 28 months in primary school children reduced obesity (OB) prevalence in boys and increased voluntary physical activity (PA). The continued benefit after cessation of EdAl is unknown. We assessed the changes in OB prevalence and healthy lifestyle in 11- to 13-year-old adolescents, the age group that had complete inclusion data available 2 years after the EdAl program's conclusion.

METHODS

Adolescents (n = 421 intervention; n = 198 control) with data at baseline and 2-year follow-up were recruited. Analyses included body mass index (BMI), BMI z-score, and lifestyle data (from questionnaires).

RESULTS

Between baseline and 2-year follow-up, OB prevalence was reduced (-5.5%; p < .01) and BMI z-score (-.29; p < .001) in intervention compared with control group. BMI z-score was effectively reduced in intervention in both genders: -.26 units in boys and -.32 units in girls, compared with control group. The ≥4 hours/week after-school PA was increased significantly by 13.1% in adolescents of intervention group compared with control group (p = .023); a tendency toward increased PA in intervention girls was observed (p = .062). At 2-year follow-up, participating in ≥4 hours/week after-school PA (odds ratio, .240; p = .002) and daily fruit consumption (odds ratio, .447; p = .025) were protective factors against OB, whereas ≤2 hours/week after-school PA was a risk factor for OB.

CONCLUSIONS

At 2-year follow-up, the EdAl program induced a lowering of BMI z-score and OB prevalence, compared with control group. After-school PA practice can be stimulated in primary school as part of a healthy lifestyle and maintained subsequently despite cessation of the intervention program.