Objective Assessment Of Physical Activity Research Articles

A universal, accurate intensity‐based classification of different physical activities using raw data of accelerometer

Accelerometers are increasingly used for objective assessment of physical activity. However, because of lack of the proprietary analysis algorithms, direct comparisons between accelerometer brands are difficult. In this study, we propose and evaluate open source methods for commensurate assessment of raw accelerometer data irrespective of the brand. Twenty-one participants carried simultaneously three different tri-axial accelerometers on their waist during five different sedentary activities and five different intensity levels of bipedal movement from slow walking to running. Several time and frequency domain traits were calculated from the measured raw data, and their performance in classifying the activities was compared. Of the several traits, the mean amplitude deviation (MAD) provided consistently the best performance in separating the sedentary activities and different speeds of bipedal movement from each other. Most importantly, the universal cut-off limits based on MAD classified sedentary activities and different intensity levels of walking and running equally well for all three accelerometer brands and reached at least 97% sensitivity and specificity in each case. Irrespective of the accelerometer brand, a simply calculable MAD with universal cut-off limits provides a universal method to evaluate physical activity and sedentary behaviour using raw accelerometer data. A broader application of the present approach is expected to render different accelerometer studies directly comparable with each other.

Predicted vs. Actual Resting Energy Expenditure and Activity Coefficients: Post-Gastric Bypass, Lean and Obese Women

Total Energy Expenditure (TEE) and energy requirements are commonly estimated from equations predicting Resting Energy Expenditure (REE) multiplied by a Physical Activity (PA) coefficient that accounts for both PA energy expenditure and the thermogenic effect of food. PA coefficients based on PA self-reports are a potential source of error that has not been evaluated. Therefore, in this study we compared: 1) the Harris-Benedict (HB), Mifflin-St. Jeor (MSJ), and the Food and Agriculture Organization/World Health Organization/United Nations University (FAO/WHO/UNU) REE equations with REE measured (REE-m) with indirect calorimetry; 2) PA coefficients determined with PA self-reports vs. objectively assessed PA; and 3) TEE estimates in post-Gastric Bypass (GB = 13), lean (LE = 7), and obese (OB = 12) women. REE was measured in the morning after an overnight fast with participants resting supine for 30 min. Self-reported PA was evaluated with a questionnaire and objectively measured with accelerometers worn for 5-7 days. Nutritional intake was evaluated with a food frequency questionnaire. Anthropometry included DEXA, and abdominal CT scans. Eligible GB had surgery ≥ 12 months before the study, and had ≥ 10 kg of body weight loss. All participants were 18-45 years of age, able to engage in ambulatory activities, and not taking part in exercise training programs. One-way ANOVA was used to detect differences in REE and TEE. Accuracy of REE prediction equations were determined by cases within 10% of REE-m, and agreement analyses. REE predictions were not different than REE-m, but agreements were better with HB and MSJ, particularly in the GB and LE groups. Discrepancies in the PA coefficients determined with self-report vs. objectively assessed PA resulted in TEE overestimates (approximately 200-300 Kcal/day) using HB and MSJ equations. FAO/WHO/UNU overestimated TEE in all groups regardless of the PA assessment method (approximately 300-900 kcal/day). These results suggest that: 1) HB and MSJ equations are good predictors of REE among GB and LE, but not among OB women, 2) PA coefficients used to estimate TEE must be determined with objective PA assessment, and 3) TEE estimates using PA coefficients with the FAO/WHO/UNU equation must be used with caution.

African American women exhibit similar adherence to intervention but lose less weight due to lower energy requirements

African American (AA) women have been shown to lose less weight than Caucasian women in response to behavioral interventions. Our objective was to examine adherence to intervention and metabolic factors that may explain this difference. We examined longitudinal changes in body weight and energy expenditure (EE), and objective assessment of physical activity (PA) and energy intake (EI) during 6 months of a weight-loss intervention program, including prescribed calorie restriction and increased PA in 66 Caucasian and 39 AA severely obese women. Comparisons were also made in 25 Caucasian and 25 AA women matched for initial body weight. The AA women lost 3.6 kg less weight than Caucasian women. Total daily EE (TDEE) and resting metabolic rate (RMR) adjusted for fat free mass (FFM) were significantly lower in the AA women, whereas the decrease in RMR in response to weight loss was greater in Caucasian women. Adherence to the prescribed PA and change in PA in response to intervention were similar in AA and Caucasian women. Prescribed EI (1794±153 and 1806±153 kcal per day) and measured EI during intervention (2591±371 vs 2630±442 kcal per day) were nearly identical in matched AA and Caucasian women. However, the AA women lost significantly less body weight due to lower energy requirements (2924±279 vs 3116±340 kcal per day; P<0.04), resulting in a lower energy deficit (333±210 vs 485±264 kcal per day). Adherence to the behavioral intervention was similar in AA and Caucasian women. However, neglecting to account for the lower energy requirements in AA women when calculating the energy prescription resulted in a lower level of calorie restriction and, hence, less body weight loss. Therefore, to achieve similar weight loss in AA women, the prescribed caloric restriction cannot be based on weight alone, but must be lower than in Caucasians, to account for lower energy requirements.

Abstract P3-08-17: Objectively measured physical activity in breast cancer survivors

Abstract Background: Obesity and physical inactivity are poor prognostic indicators for breast cancer (BC). Cardiorespiratory fitness (VO2max) is a good predictor of survival. Despite preserved LVEF, cardiorespiratory function is impaired in women with breast cancer after the completion of adjuvant therapy. International organizations recommend at least 150 minutes per week of moderate-vigorous physical activity (MVPA). Some studies show that a minority of cancer survivors are meeting the PA recommendations. A limitation of physical activity (PA) research has been the use of self-reported measures. Eligibility criteria: 1) Age 18-79, 2) Able to walk a mile, 3) More than one year from diagnosis, 4) More than 3 months since the last therapy, 5) No evidence of disease. Aims: Objective assessment of physical activity in breast cancer survivors. Adherence to international recommendations. Material and methods: PA was evaluated through accelerometry (600 minutes per day, 5 days per week, 2 week-end days were required to consider as valid accelerometry values). Cardiorespiratory fitness was assessed through the “one-mile test”. Results: 92 women (W) with BC history were included. 86 W were evaluable for accelerometry. 85 W were evaluable for VO2max. Age: 54.02 years (33-77), BMI: 27.89 (SD 8.89), waist perimeter: 89.74 cm (SD 17.37), median time from diagnosis 3.94 years, treatment with anthracyclines 55 W (63.9%), radiotherapy 69 W (80.23%). Accelerometry (86W): Average weekly time MVPA 351.14 min/wk (SD: 168.98). 76 (88%) met international recommendations of PA. Women previously treated with anthracyclines (47 W; 340.25 min/wk), radiotherapy (59 w; 343 min/wk) and both (48 W; 331 min/wk) exercised less than women who did not receive these therapies (8 W; 386 min/wk). This association was not statistically significant. Average VO2max was 24.8 ml/kg/min (SD: 7.6).There was a significant effect of anthracyclines for VO2 max. Women not treated with anthracyclines had a VO2max: 26.41 whereas treated W had VO2max 22.08 ml/kg/min. Discussion: A cohort of Spanish women met international recommendations of PA when it was objectively assessed. This cohort exhibited a poor cardiometabolic and cardiorespiratory profile. Previous exposure to anthracyclines predicted a poorer cardiorespiratory fitness. Specific research to investigate the role of exercise to mitigate that dysfunction in breast cancer survivors is warranted. Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-08-17.

Device measured physical activity as a predictor of reverse remodeling and clinical outcome

Device diagnostics provide objective assessment of physical activity over prolonged periods of time. The purpose of this study was to investigate the prognostic value of device-measured physical activity data as compared to six-minute walk test (6MWT) in predicting clinical response to CRT. Methods: This was a single-center observational cohort study in which patients undergoing CRT for standard indications were retrospectively reviewed. Daily physical activity was evaluated post-implant at 1-, 3- and 6-months. Manufacturer specific measures of average activity of the last week were converted to common units of minutes/day (m/d). The primary end-point was a composite of heart failure (HF) hospitalization, transplant, LVAD, and all-cause death at 3 years. Secondary endpoint was echocardiographic response, as defined as a >10% improvement in LV ejection fraction (LVEF), after CRT. Results: 165 patients were included: average age was 67.5±12.8 years, 76% were male, baseline LVEF was 25±7%. At 1 month, median device-measured activity and 6MWT were 138 min/day and 315 m, respectively. Kaplan Meier curves (see below) show that both 6MWT and device measured physical activity are predictors of clinical outcome. Multivariate modeling adjusting for covariates demonstrated both physical activity (HR 0.57 [95% CI 0.29-1.11], p=0.003) and 6MWT (HR 0.39 [95% CI 0.23-0.68], p=0.001) as independent predictors of improved clinical outcome. Patients with higher levels of device-measured physical activity at the 3-month mark had a significantly higher rate of echocardiographic response (p<0.05), as opposed to the 6MWT. ![Figure][1] Conclusion: Device-based measures of physical activity although comparable to 6MWT in predicting long-term clinical outcome, were better predictors of echocardiographic response. [1]: pending:yes

Physical activity assessment tools for use in overweight and obese children

The prevalence of excess weight in children and adults worldwide has increased rapidly in the last 25 years. Obesity is positively associated with increased risk for many health issues such as type 2 diabetes, cardiovascular disease and psychosocial problems. This review focuses on child populations, as it is known that the sedentary behaviors of overweight/obese youth often endure into adulthood. Assessment of physical activity (PA), among other factors such as diet and socio-economic status, is important in understanding weight variation and in designing interventions. This review highlights common subjective and objective PA assessment tools, the validity of these methods and acceptable ways of collecting and interpreting PA data. The aim is to provide an update on PA assessment in overweight/obese children, highlighting current knowledge and any gaps in the literature, in order to facilitate the use of PA assessments and interventions by health-care professionals as well as suggest future research in this area.

Maternal Physical Activity and Insulin Action in Pregnancy and Their Relationships With Infant Body Composition

OBJECTIVEWe sought to assess the association between maternal gestational physical activity and insulin action and body composition in early infancy.RESEARCH DESIGN AND METHODSAt 28–32 weeks' gestation, pregnant women participating in an observational study in Sweden underwent assessments of height, weight, and body composition, an oral glucose tolerance test, and 10 days of objective physical activity assessment. Thirty mothers and infants returned at 11–19 weeks postpartum. Infants underwent assessments of weight, length, and body composition.RESULTSEarly insulin response was correlated with total physical activity (r = −0.47; P = 0.007). Early insulin response (r = −0.36; P = 0.045) and total physical activity (r = 0.52; P = 0.037) were also correlated with infant fat-free mass. No maternal variable was significantly correlated with infant adiposity.CONCLUSIONSThe relationships between maternal physical activity, insulin response, and infant fat-free mass suggest that physical activity during pregnancy may affect metabolic outcomes in the mother and her offspring.

How to Investigate Within-Subject Associations between Physical Activity and Momentary Affective States in Everyday Life: A Position Statement Based on a Literature Overview

Several meta-analyses have investigated the association between physical activity and affective states and have found evidence suggesting that exercise exerts a positive effect on affective state. However, in this field of research, most studies have conducted between-subject analyses. Nonetheless, there is more and more interest in the within-subject associations between physical activity and momentary affective states in everyday life. This position statement pertains to this up-and-coming field of research and provides methodological recommendations for further studies. The paper is divided into three parts: first, we summarize and evaluate three methodological requirements necessary for the proper evaluation of within-subject associations between physical activity and momentary affective states in everyday life. We propose that the following issues should be considered: (a) to address the dynamic nature of such relationships, repeated assessments are necessary; (b) as activities performed in everyday life are mostly spontaneous and unconscious, an objective assessment of physical activity is useful; (c) given that recall of affective states is often affected by systematic distortions, real-time assessment is preferable. In sum, we suggest the use of ambulatory assessment techniques, and more specifically the combination of accelerometer-assessment of physical activity with an electronic diary assessment of the momentary affective state and additional context information. Second, we summarize 22 empirical studies published between 1980 and 2012 using ambulatory assessment to investigate within-subject associations between momentary affective states and physical activity in everyday life. Generally, the literature overview detects a positive association, which appears stronger among those studies that were of high methodological quality. Third, we propose the use of ambulatory assessment intervention (AAIs) strategies to change people’s behavior and to enable people to be active as often as possible during the day (e.g., reducing sitting time, taking more steps per day).

Abstract IA12: Technology to assess physical activity and sedentary behavior.

Abstract Physical inactivity is an urgent public health concern, being strongly implicated as a risk factor for many chronic diseases including certain types of cancer. It is not possible to understand or alter physical activity and inactivity levels without first being able to accurately measure these behaviors. Objective assessment of physical activity and inactivity using wearable accelerometer-based monitors has overcome the problems and limitations associated with more commonly used self-report tools. These wearable sensors are ideal for collecting information about physical activity (PA) and sedentary behavior (SB). They can be worn for extended periods of time, impose minimal inconvenience to the participant and researcher, are relatively inexpensive and can produce detailed accounts of PA and SB that are relevant to health (e.g. estimates of energy expenditure, time in moderate-to-vigorous physical activity, sedentary time) These PA and SB metrics can then be used to comprehensively characterize dose-response relationships. This presentation will highlight recent advances in objective monitoring of physical activity and sedentary behavior. The talk will describe recent work that uses machine learning tools for processing activity monitor data to classify physical activity intensity and estimate energy expenditure. Additionally, the assessment of sedentary behavior, which has been shown to be an independent risk factor for disease, will be discussed. The approach we use to assess physical activity and sedentary behavior with wearable sensors first involves the calibration of sensors. In the lab, we directly measure energy expenditure or directly observe behavior while participants perform a variety of locomotion, household, sport activities and sedentary behaviors (e.g. sitting performing computer work, filing). Simultaneously, signals from the wearable accelerometers are collected continuously. We then use features from the accelerometer signal to generate machine learning algorithms (e.g. neural networks) to predict energy expenditure, intensity of physical activity or to identify activity type. As a final step we validate these algorithms on independent samples to test the precision and accuracy of these algorithms. To examine the performance of these algorithms in the field, we have subjects carry out their normal activities in a natural setting while wearing the monitors (subjects are observed and the direct observation data are recorded continuously). This presentation will describe data from these laboratory and field studies to demonstrate performance of algorithms for predicting activity levels and sedentary behavior in free-living settings. Evidence supporting the sensitivity of these algorithms in estimating change in activity level will also be presented. Citation Format: Patty S. Freedson. Technology to assess physical activity and sedentary behavior. [abstract]. In: Proceedings of the AACR Special Conference on Post-GWAS Horizons in Molecular Epidemiology: Digging Deeper into the Environment; 2012 Nov 11-14; Hollywood, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2012;21(11 Suppl):Abstract nr IA12.

PWE-029 Objective assessment of physical activity as a measure of functional recovery and quality of life following oesophago-gastric cancer resection

IntroductionFunctional recovery following surgery is determined by the interaction between pre-operative performance, post-operative catabolism, nutritional status, and mood. Physical activity (PA) is an important domain of health-related quality-of-life (HRQL), and...

Objective Assessment of Physical Activity in the Workplace Setting

This study was conducted to assess the Physical Activity Level (PAL) of government employees at government agencies in Kangar Perlis, Malaysia, by using an accelerometer as an objectiv e measurement. Respondents were chosen randomly and required to wear the accelerometer for three days. Socio-demographic data were obtained by questionnaire and anthropometric measurements, Body Fat Percentage (BF%) and blood pressure were assessed using standard procedures. A 8-12 h fasting venous blood sample was taken for analysis of plasma glucose, lipid profile and 2 h Oral Glucose Tolerance Test (OGTT). A total of 272 respondents were recruited for this study (151 males and 121 females), with a mean age of 39±11 years. About 44.9% of the respondents were categorized as active to vigorously active based on PAL, whereas 55.1% were sedentary. Statistical analysis showed significant differences in ag e (p<0.0001), Body Mass Index (BMI) (p<0.0001), WC (p<0.0001), BF% (p<0.0001), diastolic blood pressure (p<0.05), 2 h plasma glucose and HDLC between the active and sedentary PAL groups. Logistic regression analyses of accelerometer-determined PAL showed that increasing BMI (OR = 0.841, 95% CI = 0.714, 0.990), WC (OR = 0.969, 95% CI = 0.944, 0.995), BF% (OR = 0.907, 95% CI = 0.875, 0.940) and diastolic blood pressure (OR = 0.953, 95% CI = 0.921, 0.987) were related to lower levels of PAL. In contrast, increasing HDLC levels (OR = 7.814, 95% CI = 2.603, 23.456) were related to higher levels of PAL. This study shows the significant contribution of physical activity to health status. HDLC levels increased as PAL increased and PAL was inversely associated with BMI, WC, BF% and diastolic blood pressure.

Objective assessment of physical activity in adolescents with juvenile fibromyalgia syndrome following cognitive-behavioral therapy

Objective assessment of physical activity in adolescents with juvenile fibromyalgia syndrome following cognitive-behavioral therapy

115 Objective Assessment of Physical Activity Performed by Cancer Survivors

Introduction: Breast cancer survivors experience positive and negative changes during the post-treatment period. The purpose of this research is to explain breast cancer survivors’ post-treatment experiences based on the Neuman System Model. Material and Method: In the research, the phenomenological approach, one of the qualitative research methods, was used. The research included volunteering patients registered in the Medical Oncology department of a university hospital in Turkey. Criterion sampling method was used. The sample is comprised of survivors (n = 15) who completed breast cancer treatment minimum 3 months, maximum 5 years ago. The data were collected with the ‘semi-structured interview form’ using the in-depth interview method. In order to analyze the data, the content analysis method was used. The Neuman System Model was used to create the themes. Results: The data were categorized into three themes: stressors, variables and intervention. While the theme of stressors described by Neuman includes; intrapersonal, interpersonal, extrapersonal sub-themes, the theme of the variables includes; physiological, psychological, sociocultural, developmental and spiritual subthemes. The intervention theme includes; tertiary protection subtheme. Conclusion: In conclusion, in this study, it was determined that breast cancer survivors suffered from biopsychosocial stressors during the post-treatment period, they tried to overcome these stressors with physiological, psychological, sociocultural, developmental and spiritual variables. It is recommended that health personnel should evaluate these requirements of breast cancer survivors and handle the issue from a holistic perspective.

Physical Activity by Self-Report: A Brief History and Future Issues

For the scientific domain of physical activity and public health research to advance its agenda of health promotion and disease prevention continued development of measurement methodologies is essential. Over the past 50 years most data supporting a favorable relationship between habitual physical activity and chronic disease morbidity and mortality have been obtained using self-report methods, including questionnaires, logs, recalls, and diaries. Many of these instruments have been shown to have reasonable validity and reliability for determining general type, amount, intensity, and bout duration, but typically do better for groups than individuals with some instruments lacking the sensitivity to detect change in activity. During the past decade the objective assessment of physical activity using accelerometer-based devices has demonstrated substantial potential, especially in documenting the pattern of light-, moderate-, and vigorous-intensity activity throughout the day. However, these devices do not provide information on activity type, location or context. Research that combines the strengths of both self-report and objective measures has the potential to provide new insights into the benefits of physical activity and how to implement successful interventions.

Objective assessment of physical activity and sedentary behaviour

Objective assessment of physical activity and sedentary behaviour

Objective Physical Activity Assessment in Patients With Chronic Organ Failure: A Validation Study of a New Single-Unit Activity Monitor

Annegarn J, Spruit MA, Uszko-Lencer NHMK, Vanbelle S, Savelberg HHCM, Schols AMWJ, Wouters EFM, Meijer K. Objective physical activity assessment in patients with chronic organ failure: a validation study of a new single-unit activity monitor. Objective To validate a new activity monitor (CAM) in patients with chronic organ failure during 1 hour of unconstrained activity assessment. Design A validation study in which participants wore a CAM (placed on the thigh) for 1 hour while they were videotaped. Participants were instructed to continue their normal daily routine at the rehabilitation center. Setting CIRO+, A Centre of Expertise for Chronic Organ Failure. Participants Chronic organ failure patients (N=10) with a large range of functional exercise capacity. Interventions Not applicable. Main Outcome Measure Agreement in time spent on activities and postures according to video and CAM. Results Cohen kappa coefficients for transient events resulted in an almost perfect agreement (0.85±0.08) between the CAM and video. Conclusions The CAM is a promising single-sensor unobtrusive tool for providing accurate data on the type and duration of daily activities in the home environment of patients with chronic organ failure.

Compliance of children in northern France with physical activity recommendations

This study examined the compliance of French children with physical activity (PA) guidelines, using objective assessments of PA. The study involved 252 children aged 9.9 +/- 0.9 years, with mean height and weight of 1.39 +/- 0.08 m and 35.8 +/- 8.8 kg, respectively. Their usual PA was evaluated during a week using an Actigraph accelerometer. The time spent in a moderate-to-vigorous PA (MVPA) ranged from 142 +/- 44 min x d(-1) to 25 +/- 18 min/day according to the cut-offs used. Boys were significantly more active than girls (p < or = .001). Overweight/obese children spent significantly less time in MVPA as determined with cut-off points at 3200 cpm (-26%) or 3600 cpm (-35%) (p < .01). Between 5% (8% of boys vs 1% of girls, p < .0001) and 9% (14% of boys vs 3% of girls, p < .0001) of children probably met the PA guidelines. No relationships were found with socioeconomic status. This high proportion of insufficiently active children (> 90%), together with the relatively high proportion of overweight children in this area, advocates a more aggressive PA promotion project, which should target all children whatever their social origins.

Childhood obesity and walking: guidelines and challenges

The development and maintenance of excess body mass in many children is partly attributable to levels of physical activity that are lower than the recommended 60 minutes/day. Walking is a recommended form of physical activity for obese children, due to its convenience and perceived ease of adoption. Unfortunately, studies that have used objective physical activity assessment continue to report low step counts and levels of physical activity in obese children. This may be due to physiological and/or biomechanical factors that make walking more difficult for obese children. The purpose of this review is to highlight the current recommended and measured levels of physical activity for children and to discuss the physiological and biomechanical challenges of walking for obese children that may help explain why these children are not meeting physical activity goals.

Acculturation and physical activity among immigrants: a systematic review

The acculturation process presents numerous challenges that could benefit or adversely affect immigrants’ health practices. The goal of this review was to present a systematic summary of studies examining the relationship between acculturation and physical activity among immigrants and ethnic minority populations. Systematic review based on 44 original studies found in electronic databases (Psychinfo/Psyndex, Eric, Pubmed/Medline, Web of Science, SportDiscus). Studies were eligible if they were written in English, German or French, incorporated a measure of acculturation and physical activity, exercise, or sport as independent and dependent variables, and provided statistical information to judge the level of significance. The 44 studies found included 760,242 participants. A narrative synthesis was performed. Causality of effects was examined based on seven criteria: consistency, strength of associations, specificity of effects, temporality, gradient, plausibility and experimental evidence. Acculturation was associated with higher leisure time physical activity in 57% of all studies (even after controlling for potential confounds), independent of participants’ gender, age and ethnic background. The main limitations of this review are that findings were not weighted for sample size and that publication biases might have contributed to an overestimation of the relationships. Prevention programs aimed at stimulating participation in physical activity among immigrants should give priority to individuals with low acculturation levels and it should consider culturally specific beliefs and constraints. Additionally, prevention programs could make an effort to promote acculturation among immigrants. Future studies should use longitudinal designs which include objective assessments of physical activity and which use multidimensional and bidirectional definitions of acculturation.

Examining Indirect Associations Between Physical Activity, Function, and Disability in Independent- and Assisted-Living Residents

Few studies have examined physical activity behavior and its associated outcomes in older adults living in retirement communities. Guided by the disablement model and social cognitive theory, we tested a cross-sectional model in which physical activity was hypothesized to influence disability indirectly through self-efficacy, functional performance, and functional limitations. One hundred six older men and women residing in independent-living (ILF) assisted-living (ALF) facilities completed self-report measures of self-efficacy, function, and disability. Objective assessments of physical activity and functional performance were conducted using waist-mounted accelerometers and the short physical performance battery (SPPB), respectively. Path analysis was used to examine the proposed associations among constructs. Older adults who were more active were also more efficacious and had better physical function and fewer functional limitations. Only higher levels of self-efficacy were associated with less disability. The effects of individual-level covariates were also examined. This cross-sectional study is among the first to examine the associations between physical activity, function, and disability among older adults residing in ILFs and ALFs. Future research addressing the physical and psychological needs of this growing population is warranted.