Assessment of physical activity – a review of methodologies with reference to epidemiological research: a report of the exercise physiology section of the European Association of Cardiovascular Prevention and Rehabilitation

Self-reported physical activity behavior of a multi-ethnic adult population within the urban and rural setting in Suriname

Background

Physical activity (PA) plays an important role in the combat against noncommunicable diseases including cardiovascular diseases. In order to develop appropriate PA intervention programs, there is a need to evaluate PA behavior. So far, there are no published data on PA available for Suriname. Therefore, we aim to describe PA behavior among the multi-ethnic population living in urban and rural areas of Suriname.

Methods

The World Health Organization (WHO) STEPwise approach to chronic disease risk factor surveillance (STEPS) was conducted in a national representative sample (N = 5751; 48.6% men) aged 15–64 years between March and September 2013. Physical activity data were assessed using the Global physical activity questionnaire (GPAQ) and analyzed according to the GPAQ guidelines. The prevalence of meeting the recommended PA level and prevalence ratios (PR) were computed.

Results

Only 55.5% of the overall population met the WHO recommended PA levels (urban coastal area: 55.7%, rural coastal area: 57.9%, rural interior area: 49.1%). Women were less likely to meet the recommended PA level (49% vs 62.4%; p < 0.0001) and with increasing age the PR for recommended level of PA decreased (p < 0.0001). Compared to the Hindustani’s, the largest ethnic group, the Javanese reported the lowest percentage of people meeting recommended PA level (PR = 0.92; p = 0.07).

Conclusion

Around half of the population meets the recommended PA level. Future lifestyle interventions aiming at increasing PA should especially focus on women and older individuals as they are less likely to meet the recommended levels of PA.

Prevalência de estilo de vida sedentário entre adolescentes

Objetivo: Identificar a prevalência de estilo de vida sedentário entre adolescentes e conhecer a concordância entre os resultados obtidos por dois instrumentos padronizados de medida. Métodos: Estudo descritivo, transversal, que avaliou 132 estudantes de 14 a 18 anos. As variáveis de estudo foram: sexo, idade, níveis de atividade física com a utilização do Questionário Internacional de Atividade Física em sua versão curta, e média diária de passos com a utilização do pedômetro por, no mínimo, 4 dias consecutivos. Resultados: A prevalência de sedentarismo avaliada pelo questionário foi de 19,7% e a identificada pelo pedômetro foi de 8,3% (p=0,021). Não foi identificada correlação entre os resultados dos diferentes instrumentos. A concordância entre os métodos foi fraca (k=0,021). Conclusão: A prevalência do sedentarismo foi menor quando avaliada pelo pedômetro e não houve correlação com os resultados da avaliação pelo questionário. A concordância foi fraca entre os dois instrumentos de medida.

Improvement of cardiac screening in amateur athletes

Although not performing on a professional level, amateur athletes, nevertheless, are participating in competitive sports and thus underlie a relevant risk for exercise-related SCD which implicates the need for an adequate pre-competition cardiac screening. As many amateur athletes belong to the category of "older" individuals, particularly CAD among male athletes with risk factors has to be targeted by the screening. However, the detection of clinically silent underlying coronary heart disease is challenging and cannot be accurately achieved by a standard screening provided to young athletes (history, clinical status, ECG). An extended work-up, at least, mandates the detection of cholesterol levels to estimate the individual cardiovascular risk. The fact that only less than 10% of Swiss amateur athletes have undergone cardiac screening led to various promising approaches to improve the awareness of the issue. Exemplarily, we successfully invented an "on-site" prevention campaign that positively influenced the attitude of the athletes towards cardiac screening.

Inflammatory cytokines in general and central obesity and modulating effects of physical activity

Context

Chronic systemic inflammation in obesity originates from local immune responses in visceral adipose tissue. However, assessment of a broad range of inflammation-mediating cytokines and their relationship to physical activity and adipometrics has scarcely been reported to date.

Objective

To characterize the profile of a broad range of pro- and anti-inflammatory cytokines and the impact of physical activity and energy expenditure in individuals with general obesity, central obesity, and non-obese subjects.

Design, Setting, and Participants

A cross-sectional study comprising 117 obese patients (body mass index (BMI) ≥ 30) and 83 non-obese community-based volunteers.

Main Outcomes Measures

Serum levels of interleukin (IL)-2, IL-4, IL-5, IL-10, IL-12, IL-13, granulocyte-macrophage colony-stimulating factor (GM-CSF), interferon (IFN)-γ and tumor necrosis factor (TNF)-α were measured. Physical activity and energy expenditure (MET) were assessed with actigraphy. Adipometrics comprised BMI, weight, abdominal-, waist- and hip-circumference, waist to hip ratio (WHR), and waist-to-height-ratio (WHtR).

Results

General obesity was associated with significantly elevated levels of IL-5, IL-10, IL-12, IL-13, IFN-γ and TNF-α, central obesity with significantly elevated IL-5, IL-10, IL-12, IL-13 and IFN-γ-levels. In participants with general obesity, levels of IL-4, IL-10 and IL-13 were significantly elevated in participants with low physical activity, even when controlled for BMI which was negatively associated with physical acitivity. Cytokines significantly correlated with adipometrics, particularly in obese participants.

Conclusions

Results confirm up-regulation of certain pro- and anti-inflammatory cytokines in obesity. In obese subjects, physical activity may lower levels and thus reduce pro-inflammatory effects of cytokines that may link obesity, insulin resistance and diabetes.

Non-alcoholic fatty liver disease is associated with higher levels of objectively measured sedentary behaviour and lower levels of physical activity than matched healthy controls

BACKGROUND AND AIMS

Physical activity is a key determinant of metabolic control and is recommended for people with non-alcoholic fatty liver disease (NAFLD), usually alongside weight loss and dietary change. To date, no studies have reported the relationship between objectively measured sedentary behaviour and physical activity, liver fat and metabolic control in people with NAFLD, limiting the potential to target sedentary behaviour in clinical practice. This study determined the level of sedentary behaviour and physical activity in people with NAFLD, and investigated links between physical activity, liver fat and glucose control.

METHODS

Sedentary behaviour, physical activity and energy expenditure were assessed in 37 adults with NAFLD using a validated multisensor array over 7 days. Liver fat and glucose control were assessed, respectively, by ¹H-MRS and fasting blood samples. Patterns of sedentary behaviour were assessed by power law analyses of the lengths of sedentary bouts fitted from raw sedentary data. An age and sex-matched healthy control group wore the activity monitor for the same time period.

RESULTS

People with NAFLD spent approximately half an hour extra a day being sedentary (1318±68 vs1289±60 mins/day; p<0.05) and walked 18% fewer steps (8483±2926 vs 10377±3529 steps/day; p<0.01). As a consequence, active energy expenditure was reduced by 40% (432±258 vs 732±345 kcal/day; p<0.01) and total energy expenditure was lower in NAFLD (2690±440 vs 2901±511 kcal/day; p<0.01). Power law analyses of the lengths of sedentary bouts demonstrated that patients with NAFLD also have a lower number of transitions from being sedentary to active compared with controls (13±0.03 vs15±0.03%; p<0.05).

CONCLUSIONS

People with NAFLD spend more time sedentary and undertake less physical activity on a daily basis than healthy controls. High levels of sedentary behaviour and low levels of physical activity represent a therapeutic target that may prevent progression of metabolic conditions and weight gain in people with NAFLD and should be considered in clinical care.

Life span exercise among elite intercollegiate student athletes

Background:

Despite prominent public attention, data on life span health and exercise outcomes among elite, competitive athletes are sparse and do not reflect the diversity of modern athletes.

Hypothesis:

Life span exercise behavior differs between National Collegiate Athletic Association (NCAA) student athletes and a nonathlete control group. Sustained exercise is associated with improved cardiopulmonary health outcomes.

Study Design:

Cross-sectional, descriptive epidemiology study.

Level of Evidence:

Level 3.

Methods:

A total of 496 students and alumni (age range, 17-84 year) at a large, NCAA Division I university, including student athletes and an age- and sex-matched nonathlete control group, completed anonymous, self-report health and exercise questionnaires. Age-stratified, cross-sectional analysis evaluated previous week’s total exercise volume (ExVol), self-rated exercise importance (ExImp), and compliance with American College of Sports Medicine (ACSM) exercise guidelines for healthy adults. The association of ACSM guideline compliance with lifetime cardiopulmonary health outcomes was also assessed.

Results:

Current student athletes reported significantly greater ExVol (P < 0.001. Cohen d = 0.99, probability of clinically important difference [pCID] >99.5%), ExImp (P < 0.001, d = 1.96, pCID = 96%), and likelihood of compliance with ACSM guidelines (odds ratio [OR], 95% confidence interval [CI] = 30.6, 11.0-84.6) compared with nonathletes. No significant differences were found between alumni student athletes and nonathletes. Alumni student athletes demonstrated substantially lower ExVol (P < 0.001, d = –0.94, pCID >99.5%) and guideline compliance (OR = 0.09, 95% CI = 0.05-0.19) compared with current student athletes, whereas nonathletes had similar exercise behavior across the life span. Among alumni, ACSM guideline compliance was associated with significant attenuation of cardiopulmonary health concerns (P = 0.02, d = –0.50, pCID = 14%) independent of intercollegiate athletic participation.

Conclusion:

Although current NCAA Division I student athletes demonstrated significant, clinically important differences in exercise behavior compared with nonathletes, no group differences were evident later in life. Irrespective of collegiate athletic status, healthy exercise behavior among alumni was associated with cardiopulmonary health benefits.

Clinical Relevance:

To realize life span health benefits, it is imperative that student athletes maintain consistent patterns of healthy exercise beyond retirement from competitive sports.

Assessment and comparison of the effects of two techniques on hamstring flexibility

Introduction There are several stretching techniques that help increase flexibility, however, there are still questions regarding which method leads to the most effective gains. Objectives To assess and compare the effects of two stretching techniques, namely proprioceptive neuromuscular facilitation (PNF) and static stretching on the flexibility of hamstring muscles of young women. Methods The study sample consisted of 45 young women, mean age 20.45 (± 1.66),assigned to one of three groups: static stretching group (SSG, n = 15), proprioceptive neuromuscular facilitation group (PNFG, n = 15) and control group (CG, n = 15). Both SSG and PNFG carried out three weekly stretching sessions over a four-week period. The sit and reach and popliteal angle tests were used at the beginning and end of the intervention. Normally distributed data were analyzed using Student’s t-test, whereas data with non-normal distribution were analyzed using the Wilcoxon test, to compare initial and end measurements for each technique. Finally, we used the Mann-Whitney U test to compare both techniques with each other. A significance level of 5% (p < 0.05) was adopted. Results There was a significant increase in hamstring flexibility when analyzing the assessments and reassessments of both stretching protocols. Conclusions Both techniques were effective in increasing hamstring flexibility and there were no significant differences to indicate which one is better in increasing the flexibility of this muscle group.

Accelerometer-based measures in physical activity surveillance: current practices and issues

OBJECTIVE

Self-reports of physical activity (PA) have been the mainstay of measurement in most non-communicable disease (NCD) surveillance systems. To these, other measures are added to summate to a comprehensive PA surveillance system. Recently, some national NCD surveillance systems have started using accelerometers as a measure of PA. The purpose of this paper was specifically to appraise the suitability and role of accelerometers for population-level PA surveillance.

METHODS

A thorough literature search was conducted to examine aspects of the generalisability, reliability, validity, comprehensiveness and between-study comparability of accelerometer estimates, and to gauge the simplicity, cost-effectiveness, adaptability and sustainability of their use in NCD surveillance.

CONCLUSIONS

Accelerometer data collected in PA surveillance systems may not provide estimates that are generalisable to the target population. Accelerometer-based estimates have adequate reliability for PA surveillance, but there are still several issues associated with their validity. Accelerometer-based prevalence estimates are largely dependent on the investigators' choice of intensity cut-off points. Maintaining standardised accelerometer data collections in long-term PA surveillance systems is difficult, which may cause discontinuity in time-trend data. The use of accelerometers does not necessarily produce useful between-study and international comparisons due to lack of standardisation of data collection and processing methods. To conclude, it appears that accelerometers still have limitations regarding generalisability, validity, comprehensiveness, simplicity, affordability, adaptability, between-study comparability and sustainability. Therefore, given the current evidence, it seems that the widespread adoption of accelerometers specifically for large-scale PA surveillance systems may be premature.

The association of physical activity to neural adaptability during visuo-spatial processing in healthy elderly adults: A multiscale entropy analysis

Physical activity has been shown to benefit brain and cognition in late adulthood. However, this effect is still unexplored in terms of brain signal complexity, which reflects the level of neural adaptability and efficiency during cognitive processing that cannot be acquired via averaged neuroelectric signals. Here we employed multiscale entropy analysis (MSE) of electroencephalography (EEG), a new approach that conveys important information related to the temporal dynamics of brain signal complexity across multiple time scales, to reveal the association of physical activity with neural adaptability and efficiency in elderly adults. A between-subjects design that included 24 participants (aged 66.63±1.31years; female=12) with high physical activity and 24 age- and gender-matched low physical activity participants (aged 67.29±1.20years) was conducted to examine differences related to physical activity in performance and MSE of EEG signals during a visuo-spatial cognition task. We observed that physically active elderly adults had better accuracy on both visuo-spatial attention and working memory conditions relative to their sedentary counterparts. Additionally, these physically active elderly adults displayed greater MSE values at larger time scales at the Fz electrode in both attention and memory conditions. The results suggest that physical activity may be beneficial for adaptability of brain systems in tasks involving visuo-spatial information. MSE thus might be a promising approach to test the effects of the benefits of exercise on cognition.

Comparison of two accelerometer filter settings in individuals with Parkinson's disease

This study compared common free-living physical activity (PA) outcomes, assessed with the Actigraph GT3X+ accelerometer and processed with two different filter settings, in a sample of elderly individuals with Parkinson´s disease (PD). Sixty-six individuals (73.1  ±  5.8 years) with mild to moderate idiopathic PD carried an accelerometer for 7 d. Data were processed with the default filter setting and a low frequency extension filter (LFE). Significantly larger values were obtained with the LFE for mean counts and steps per day, and for minutes per day in low intensity- and lifestyle activities at moderate intensity, but not for moderate-to vigorous intensity ambulatory activities. The largest difference was observed for mean ± SD steps per day (default = 4730  ±  3210; LFE = 11 117  ±  4553). Intraclass correlation confidence intervals and limits of agreement were generally wide, indicating poor agreement. A sub-study, in which 15 individuals with PD performed a self-paced 3 min walk, demonstrated that neither filter setting differed from video-recorded steps (p ≥ 0.05). This suggests that the LFE might overestimate PA-outcomes in free-living conditions. Until new evidence supporting an extension of the lower filter-band is presented, it is recommended that the default filter setting be used when assessing PA in elderly individuals with PD.

Using postal questionnaires to evaluate physical activity and diet behaviour change: case study exploring implications of valid responder characteristics in interpreting intervention outcomes

Background

Patient reported outcome measures (PROMs) are used to evaluate lifestyle interventions but little is known about differences between patients returning valid and invalid responses, or of potential for bias in evaluations. We aimed to examine the characteristics of patients who returned valid responses to lifestyle questionnaires compared to those whose responses were invalid for evaluating lifestyle change.

Methods

We conducted a secondary data analysis from the SPHERE Study, a trial of an intervention to improve outcomes for patients with coronary heart disease in primary care. Postal questionnaires were used to assess physical activity (Godin) and diet (DINE) among study participants at baseline and 18 month follow-up. Three binary response variables were generated for analysis: (1) valid Godin score; (2) valid DINE Fibre score; and (3) valid DINE Total Fat score. Multivariate analysis comprised generalised estimating equation regression to examine the association of patients’ characteristics with their return of valid responses at both timepoints.

Results

Overall, 92.1% of participants (832/903) returned questionnaires at both baseline and 18 months. Relatively fewer valid Godin scores were returned by those who left school aged <15 years (36.5%) than aged 18 and over (50.5%), manual workers (39.5%) than non-manual (49.5%) and those with an elevated cholesterol (>5 mmol) (34.7%) than those with a lower cholesterol (44.4%) but multivariate analysis identified that only school leaving age (p = 0.047) was of statistical significance.

Relatively fewer valid DINE scores were returned by manual than non-manual workers (fibre: 80.8% v 86.8%; fat: 71.2% v 80.0%), smokers (fibre: 72.6% v 84.7%; fat: 67.5% v 76.9%), patients with diabetes (fibre: 75.9% v 82.9%; fat: 66.9% v 75.8%) and those with cholesterol >5 mmol (fat: 68.2% v 76.2%) but multivariate analysis showed statistical significance only for smoking (fibre: p = 0.013; fat: p = 0.045), diabetes (fibre: p = 0.039; fat: p = 0.047), and cholesterol (fat: p = 0.039).

Conclusions

Our findings illustrate the importance of detailed reporting of research methods, with clear information about response rates, respondents and valid outcome data. Outcome measures which are relevant to a study population should be chosen carefully. The impact of methods of outcome measurement and valid response rates in evaluating healthcare requires further study.

Prehabilitation Interventions for Older Adults

Prehabilitation aims to increase physical activity and improve physical fitness prior to elective surgery to improve postoperative outcomes. This integrative review examined the effect of prehabilitation randomized clinical trial (RCT) interventions on physical activity behavior and physical fitness in older adults. Seven studies met the search criteria. In two studies, effect sizes from baseline to the preoperative period exceeded d = .2, specifically in physical activity and in the physical-fitness dimensions of strength, cardiorespiratory fitness, and flexibility. For the effect sizes between baseline and the postoperative period, five studies had positive effects greater than d = .2 in strength, flexibility, balance, and speed. This review demonstrated that prehabilitation continues to be important to physical activity and physical-fitness research because it may improve physical-fitness measures and have implications for multiple dimensions of health in older adults.

Factors and associations for physical activity in severely obese adults during a two-year lifestyle intervention

Objective. This study of severely obese adults participating in a two-year lifestyle intervention investigates associations between the independent variables: change in self-efficacy for physical activity (PA) in the face of psychological barriers, perceived behavioural control over PA, and PA self-identity and the dependent variable of change in objectively assessed PA. The intervention comprised four residential periods in a rehabilitation centre and combined diet, physical activity, and cognitive behavioural therapy.

Materials and Methods. Forty-nine severely obese adults (37 women, mean body mass index 42.1 kg/m²) were included in the study. Assessment was done four times using questionnaires and an accelerometer. A linear mixed model based on restricted maximum likelihood was used in analyses for change over time. Associations were studied using linear regression analyses. Age, gender, and change in body mass index were used as control variables.

Results. In the adjusted analyses, change in perceived behavioural control over PA was associated with change in PA (Stand. coeff. = 0.32, p = .005). Change in PA was not associated with either change in self-efficacy over PA in the face of psychological barriers (Stand. coeff. = 0.13, p = .259) or PA self-identity (Stand. coeff. = −0.07, p = .538).

Conclusion. Perceived behavioural control may be a valid target to increase and maintain PA in severely obese adults participating in lifestyle interventions. More research is needed to investigate the process of behaviour change in this population.

The Sedentary Time and Activity Reporting Questionnaire (STAR-Q): reliability and validity against doubly labeled water and 7-day activity diaries

We determined measurement properties of the Sedentary Time and Activity Reporting Questionnaire (STAR-Q), which was designed to estimate past-month activity energy expenditure (AEE). STAR-Q validity and reliability were assessed in 102 adults in Alberta, Canada (2009-2011), who completed 14-day doubly labeled water (DLW) protocols, 7-day activity diaries on day 15, and the STAR-Q on day 14 and again at 3 and 6 months. Three-month reliability was substantial for total energy expenditure (TEE) and AEE (intraclass correlation coefficients of 0.84 and 0.73, respectively), while 6-month reliability was moderate. STAR-Q-derived TEE and AEE were moderately correlated with DLW estimates (Spearman's ρs of 0.53 and 0.40, respectively; P < 0.001), and on average, the STAR-Q overestimated TEE and AEE (median differences were 367 kcal/day and 293 kcal/day, respectively). Body mass index-, age-, sex-, and season-adjusted concordance correlation coefficients (CCCs) were 0.24 (95% confidence interval (CI): 0.07, 0.36) and 0.21 (95% CI: 0.11, 0.32) for STAR-Q-derived versus DLW-derived TEE and AEE, respectively. Agreement between the diaries and STAR-Q (metabolic equivalent-hours/day) was strongest for occupational sedentary time (adjusted CCC = 0.76, 95% CI: 0.64, 0.85) and overall strenuous activity (adjusted CCC = 0.64, 95% CI: 0.49, 0.76). The STAR-Q demonstrated substantial validity for estimating occupational sedentary time and strenuous activity and fair validity for ranking individuals by AEE.

Interventions aimed at increasing the level of physical activity by including organised follow-up: a systematic review of effect

Background

Organised follow-up is a common feature of several strategies at the primary health care level to promote health behaviour change, e.g. to increase physical activity. In Norway, municipal ‘healthy living’ centres run by health care personnel are established to offer counselling and organised follow-up of health behaviour change during a 12-week programme. We report the results of a systematic review commissioned by the Norwegian Directorate of Health concerning organised follow-up to improve physical activity.

Methods

We searched ten electronic databases up to June 2012, reference lists of included publications, and relevant journals. Study selection and quality risk of bias assessment were carried out independently. Data were synthesised narratively due to heterogeneity of measurements of physical activity. The GRADE approach was used to assess our confidence in the effect estimate for each outcome in each comparison.

Results

Fourteen randomised controlled trials from seven countries and with a total of 5,002 participants were included in the systematic review. All studies were carried out in primary care or community settings. The interventions comprised referral to supervised group physical activity (2 studies), referral to local resources with follow-up (6 studies), and self-organised physical activity with follow-up (6 studies). The narrative synthesis, comprising a total of 39 comparisons, indicated effects of self-organised physical activity with follow-up (compared to both advice and no treatment) and referral to local resources with follow-up (compared to advice) in some of the comparisons where we rated our confidence in the effect estimates as moderate. However, the results indicated no difference between intervention and control groups for the majority of comparisons. Follow-up in the studies was mainly short-term with the longest follow-up 9 months post-treatment. We rated our confidence in the effect estimates as low or very low in most comparisons, both for positive and neutral results.

Conclusions

The results of this systematic review indicate considerable uncertainty concerning effects of organised follow-up during 10–14 weeks on physical activity. Major methodological problems concerning the measurement of physical activity are discussed.

Trial registration

Systematic review registration: PROSPERO CRD42011001598.

Physical activity and cardiovascular risk factors in a 40- to 42-year-old rural Norwegian population from 1975-2010: repeated cross-sectional surveys

Background

Geographical differences in cardiovascular diseases (CVD) have been observed among Norwegian counties. Better long-term health status and higher physical activity (PA) levels have been documented in the county of Sogn & Fjordane compared with other counties. However, recent trends in CVD risk factors have not been documented. The aim of this study was to investigate the secular trends in leisure time physical activity (LTPA) and other CVD risk factors over a 35-year period in a rural population of 40- to 42-year-olds in western Norway and to compare these trends with national trends.

Methods

Data from eight cross-sectional studies from 1975–2010 (n = 375,682) were obtained from questionnaires and physical examinations and were analyzed using mixed model regression analyses.

Results

Decreasing trends were observed for sedentary behavior (for women), moderate PA, smoking, systolic blood pressure (SBP), diastolic blood pressure (DBP), high-density lipoprotein (HDL-c) and total cholesterol (TC), whereas increasing trends were observed for body mass index (BMI), triglycerides (TG), light PA, vigorous PA and sedentary behavior for men. Compared to the national trends, the trends in the 40-42-year-olds from Sogn & Fjordane were more beneficial in terms of TG, HDL-c and BMI but less beneficial in terms of SBP and DBP.

Conclusions

Over a 35-year-period, this study indicates that the LTPA level has been relatively stable in the county of Sogn & Fjordane. Upward trends were observed in light and vigorous PA, whereas a downward trend was observed in moderate PA. For sedentary behavior, an upward trend was observed in men, whereas a downward trend was observed in women. For smoking, BP and cholesterol decreasing trends were found, but increasing trends were observed in BMI and TG. Compared with the national data, the trends in Sogn & Fjordane were more beneficial for TG, HDL-c and BMI but less beneficial for BP.

Calibration of self-report tools for physical activity research: the Physical Activity Questionnaire (PAQ)

Background

The utility of self-report measures of physical activity (PA) in youth can be greatly enhanced by calibrating self-report output against objectively measured PA data.

This study demonstrates the potential of calibrating self-report output against objectively measured physical activity (PA) in youth by using a commonly used self-report tool called the Physical Activity Questionnaire (PAQ).

Methods

A total of 148 participants (grades 4 through 12) from 9 schools (during the 2009–2010 school year) wore an Actigraph accelerometer for 7 days and then completed the PAQ. Multiple linear regression modeling was used on 70% of the available sample to develop a calibration equation and this was cross validated on an independent sample of participants (30% of sample).

Results

A calibration model with age, gender, and PAQ scores explained 40% of the variance in values for the percentage of time in moderate-to-vigorous PA (_%MVPA) measured from the accelerometers (_%MVPA = 14.56 - (sex*0.98) - (0.84*age) + (1.01*PAQ)). When tested on an independent, hold-out sample, the model estimated _%MVPA values that were highly correlated with the recorded accelerometer values (r = .63) and there was no significant difference between the estimated and recorded activity values (mean diff. = 25.3 ± 18.1 min; p = .17).

Conclusions

These results suggest that the calibrated PAQ may be a valid alternative tool to activity monitoring instruments for estimating _%MVPA in groups of youth.

Cross-sectional associations of objectively measured physical activity, cardiorespiratory fitness and anthropometry in European adults

OBJECTIVE

To quantify the independent associations between objectively measured physical activity (PA), cardiorespiratory fitness (CRF), and anthropometry in European men and women.

METHODS

2,056 volunteers from 12 centers across Europe were fitted with a heart rate and movement sensor at 2 visits 4 months apart for a total of 8 days. CRF (ml/kg/min) was estimated from an 8 minute ramped step test. A cross-sectional analysis of the independent associations between objectively measured PA (m/s(2)/d), moderate and vigorous physical activity (MVPA) (%time/d), sedentary time (%time/d), CRF, and anthropometry using sex stratified multiple linear regression was performed.

RESULTS

In mutually adjusted models, CRF, PA, and MVPA were inversely associated with all anthropometric markers in women. In men, CRF, PA, and MVPA were inversely associated with BMI, whereas only CRF was significantly associated with the other anthropometric markers. Sedentary time was positively associated with all anthropometric markers, however, after adjustment for CRF significant in women only.

CONCLUSION

CRF, PA, MVPA, and sedentary time are differently associated with anthropometric markers in men and women. CRF appears to attenuate associations between PA, MVPA, and sedentary time. These observations may have implications for prevention of obesity.

Accelerometer use during field-based physical activity research in children and adolescents with intellectual disabilities: a systematic review

Many methodological questions and issues surround the use of accelerometers as a measure of physical activity during field-based research. To ensure overall research quality and the accuracy of results, methodological decisions should be based on study research questions. This paper aims to systematically review accelerometer use during field-based research in children and adolescents with intellectual disabilities. Medline, Embase, Cochrane Library, Web of Knowledge, PsycINFO, PubMed, and a thesis database (up to May 2013) were searched to identify relevant articles. Articles which used accelerometry-based monitors, quantified activity levels, and included ambulatory children and adolescents (≤ 18 years) with intellectual disabilities were included. Based on best practice guidelines, a form was developed to extract data based on 17 research components of accelerometer use. The search identified 429 articles. Ten full-text articles met the criteria and were included in the review. Many shortcomings in accelerometer use were identified, with the percentage of review criteria met ranging from 12% to 47%. Various methods of accelerometer use were reported, with most use decisions not based on population-specific research. However, a lack of measurement research, e.g., calibration/validation, for children and adolescents with intellectual disabilities is limiting the ability of field-based researchers to make to the most appropriate accelerometer use decisions. The methods of accelerometer use employed can have significant effects on the quality and validity of results produced, which researchers should be more aware of. To allow informed use decisions, there should be a greater focus on measurement research related to children and adolescents with intellectual disabilities.

Inverse effects of midlife occupational and leisure time physical activity on mobility limitation in old age--a 28-year prospective follow-up study

OBJECTIVES

To evaluate in a sample of initially middle-aged municipal employees whether leisure time (LPA) or occupational physical activity (OPA) was associated with mobility limitation (ML) in old age.

DESIGN

Prospective population-based follow-up.

SETTING

Municipalities in Finland.

PARTICIPANTS

Public sector employees from the Finnish Longitudinal Study on Municipal Employees (FLAME) initially aged 44 to 58 (N = 5,200).

MEASUREMENTS

Baseline data were collected in 1981, including LPA (average exercise within previous year: inactive (no exercise), moderate (some form of exercise ≤ 1 time per week), vigorous (brisk exercise ≥ 1 time per week)) and OPA (usual activities at work within previous year: light (light work sitting, standing, or moving around), moderate (moderate work moving around), vigorous (heavy physical work)). Number of MLs was assessed using a questionnaire (8 items) in 1985, 1992, 1997, and 2009; the latest mobility score available for each subject was used for analyses. Incidence rate ratios (IRRs) and 95% confidence intervals (CIs) for LPA and OPA predicting ML were estimated in a joint Poisson regression model adjusted for survival data; the other type of PA; and sociodemographic, socioeconomic, and health-related factors.

RESULTS

Mean age at baseline was 50.3 ± 3.6; 56.9% of participants were female. Participants with vigorous OPA in midlife had greater risk of a unit increase in ML in old age than those with light OPA (fully adjusted IRR = 1.09, 95% CI = 1.03-1.16). Participants with vigorous LPA had lower risk of ML than inactive participants (fully adjusted IRR = 0.81, 95% CI = 0.76-0.86).

CONCLUSION

Findings suggest that LPA and OPA in midlife have independent, inverse effects on mobility in old age in terms of a harmful effect of vigorous OPA and a protective effect of vigorous LPA.

Reliability of the Serbian version of the International Physical Activity Questionnaire for older adults

The purpose of this study was to determine the test-retest reliability of the International Physical Activity Questionnaire (IPAQ) for older adults in Serbia. Six hundred and sixty older adults (352 men, 53%; 308 women, 47%; mean age 67.65±5.76 years) participated in the study. To examine test-retest reliability, the participants were asked to complete the IPAQ on two occasions 2 weeks apart. Moderate reliability was observed between the repeated IPAQ, with intraclass correlation coefficients ranging from 0.53 to 0.91. The least reliability was established in leisure time activity (0.53) and the most reliability in the transport domain (0.91). Men and women had similar intraclass correlation coefficients for total physical activity (0.71 versus 0.74, respectively), while the biggest difference was obtained for housework in men (0.68) and in women (0.90). Our study shows that the long version of the IPAQ is a reliable instrument for assessing physical activity levels in older adults and that it may be useful for generating internationally comparable data.

The improved physical activity index for measuring physical activity in EPIC Germany

In the European Investigation into Cancer and Nutrition study (EPIC), physical activity (PA) has been indexed as a cross-tabulation between PA at work and recreational activity. As the proportion of non-working participants increases, other categorization strategies are needed. Therefore, our aim was to develop a valid PA index for this population, which will also be able to express PA continuously. In the German EPIC centers Potsdam and Heidelberg, a clustered sample of 3,766 participants was re-invited to the study center. 1,615 participants agreed to participate and 1,344 participants were finally included in this study. PA was measured by questionnaires on defined activities and a 7-day combined heart rate and acceleration sensor. In a training sample of 433 participants, the Improved Physical Activity Index (IPAI) was developed. Its performance was evaluated in a validation sample of 911 participants and compared with the Cambridge Index and the Total PA Index. The IPAI consists of items covering five areas including PA at work, sport, cycling, television viewing, and computer use. The correlations of the IPAI with accelerometer counts in the training and validation sample ranged r = 0.40–0.43 and with physical activity energy expenditure (PAEE) r = 0.33–0.40 and were higher than for the Cambridge Index and the Total PA Index previously applied in EPIC. In non-working participants the IPAI showed higher correlations than the Cambridge Index and the Total PA Index, with r = 0.34 for accelerometer counts and r = 0.29 for PAEE. In conclusion, we developed a valid physical activity index which is able to express PA continuously as well as to categorize participants according to their PA level. In populations with increasing rates of non-working people the performance of the IPAI is better than the established indices used in EPIC.

Validation and comparison of two methods to assess human energy expenditure during free-living activities

Background

The measurement of activity energy expenditure (AEE) via accelerometry is the most commonly used objective method for assessing human daily physical activity and has gained increasing importance in the medical, sports and psychological science research in recent years.

Objective

The purpose of this study was to determine which of the following procedures is more accurate to determine the energy cost during the most common everyday life activities; a single regression or an activity based approach. For this we used a device that utilizes single regression models (GT3X, ActiGraph Manufacturing Technology Inc., FL., USA) and a device using activity-dependent calculation models (move II, movisens GmbH, Karlsruhe, Germany).

Material and Methods

Nineteen adults (11 male, 8 female; 30.4±9.0 years) wore the activity monitors attached to the waist and a portable indirect calorimeter (IC) as reference measure for AEE while performing several typical daily activities. The accuracy of the two devices for estimating AEE was assessed as the mean differences between their output and the reference and evaluated using Bland-Altman analysis.

Results

The GT3X overestimated the AEE of walking (GT3X minus reference, 1.26 kcal/min), walking fast (1.72 kcal/min), walking up−/downhill (1.45 kcal/min) and walking upstairs (1.92 kcal/min) and underestimated the AEE of jogging (−1.30 kcal/min) and walking upstairs (−2.46 kcal/min). The errors for move II were smaller than those for GT3X for all activities. The move II overestimated AEE of walking (move II minus reference, 0.21 kcal/min), walking up−/downhill (0.06 kcal/min) and stair walking (upstairs: 0.13 kcal/min; downstairs: 0.29 kcal/min) and underestimated AEE of walking fast (−0.11 kcal/min) and jogging (−0.93 kcal/min).

Conclusions

Our data suggest that the activity monitor using activity-dependent calculation models is more appropriate for predicting AEE in daily life than the activity monitor using a single regression model.

Lifelog agent for human activity pattern analysis on health avatar platform

Objectives

To provide accurate personalized medical care, it is necessary to gather individual-related data or contextual information regarding the target person. Nowadays a large number of people possess smartphones, which enables sensors in the smartphones to be used for lifelogging. The objective of the study is to analyze human activity pattern by using lifelog agent cooperating with the Health Avatar platform.

Methods

Using the lifelog measured by accelerometer and gyroscope in a smartphone at a 50 Hz rate, the agent reveals how long the user walks, runs, sits, stands, and lies down, and this information is summarized by hours. The summaries are sent to the Health Avatar platform and finally are written in the Continuity of Care Record (CCR) format.

Results

The lifelog agent is successfully operated with the Health Avatar platform. In addition, we implement an application that displays the user's activity patterns in a graph and calculates the metabolic equivalent of task based calorie burned by hour or by day using the lifelog of the CCR form to show that the lifelog can be used as medical records.

Conclusions

The agent shows how lifelogs are analyzed and summarized to help activity recognition. We believe that our agent demonstrates a way of incorporating lifelogs into medical care and a way of exploiting lifelogs in a medical format.

Obesity and risk factors for cardiovascular disease and type 2 diabetes: investigating the role of physical activity and sedentary behaviour in mid-life in the 1958 British cohort

OBJECTIVE

A key public health priority is to minimise obesity-related health consequences. We aim to establish whether physical activity (PA) or less sedentary behaviour ameliorate associations of obesity with biomarkers for cardiovascular disease (CVD) and type 2 diabetes.

METHODS

Data on obesity (33 y), PA (42 y), TV-viewing and health biomarkers (45 y) are from the 1958 British birth cohort (N=9377).

RESULTS

Obesity was associated with an adverse biomarker profile for CVD and type 2 diabetes. For PA, men active≥1/week had 1.09% (0.28, 1.90) lower diastolic blood pressure (DBP) than less active men; triglycerides were 2.08% (0.52, 3.64) lower per unit higher PA (on 4-point scale). TV-viewing was independently associated with several biomarkers, e.g. per unit higher TV-viewing (on 4-point scale) DBP was raised by 0.50% (0.09, 0.90) and triglycerides by 3.61% (1.58, 5.64). For both TV-viewing and PA, associations with HbA1c were greatest for the obese (pinteraction≤0.04): compared to a reference value of 5.20 HbA1c% in non-obese men viewing 0-1 h/day, HbA1c% differed little for those viewing>3 h/day; among obese men HbA1c% was 5.36 (5.22, 5.51) and 5.65 (5.53, 5.76), for 0-1 and >3 h/day respectively. For PA in non-obese men, the reduction associated with activity≥1/week was negligible compared to a reference value of 5.20 HbA1c% for those less active; but there was a reduction among obese men, HbA1c% was 5.50 (5.40, 5.59) vs 5.66 (5.55, 5.77) respectively.

CONCLUSION

Reduced TV-viewing and prevention of infrequent activity have greatest beneficial associations for glucose metabolism among the obese, with benefits for other biomarkers across obese and non-obese groups.

Measuring physical activity in children and adolescents for dietary surveys: practicalities, problems and pitfalls

Physical inactivity is an important risk factor for many chronic diseases and contributes to obesity and poor mental well-being. The present paper describes the main advantages and disadvantages, practical problems, suggested uses, and future developments regarding self-reported and objective data collection in the context of dietary surveys. In dietary surveys, physical activity is measured primarily to estimate energy expenditure. Energy expenditure surveillance is important for tracking changes over time, particularly given the debates over the role of the relative importance of energy intake and expenditure changes in the aetiology of obesity. It is also important to assess the extent of underreporting of dietary intake in these surveys. Physical activity data collected should include details on the frequency, duration and relative intensity of activity for each activity type that contributes considerably to overall activity and energy expenditure. Problems of validity and reliability, associated with inaccurate assessment, recall bias, and social desirability bias, are well-known; children under 10 years cannot report their activities accurately. However, despite such limitations, questionnaires are still the dominant method of physical activity assessment in dietary surveys due to their low cost and relatively low participant burden. Objective, time-stamped measures that monitor heart rate and/or movement can provide more comprehensive, quantitative assessment of physical activity but at greater cost and participant burden. Although overcoming many limitations of questionnaires, objective measures also have drawbacks, including technical, practical and interpretational issues.

The importance of self-determined motivation towards physical activity in patients with schizophrenia

There is a need for theoretically-based research on the motivational processes linked to the commencement and continuation of physical activity in patients with schizophrenia. Within the Self-Determination Theory (SDT) framework, we investigated the SDT tenets in these patients by examining the factor structure of the Behavioral Regulation in Exercise Questionnaire-2 (BREQ-2) and by investigating associations between motivation and PA. The secondary aim was to study differences in motivation according to gender, educational level, treatment setting and disease stage. A total of 129 patients (44♀) with schizophrenia agreed to participate. Exploratory factor analysis showed sufficient convergence with the original factor for amotivation, external and introjected regulation, while identified and intrinsic regulations loaded on a single factor which we labeled "autonomous regulation". Significant positive correlations were found between the total physical activity score and the subscales amotivation (r = -0.44, P < 0.001), external regulation (r = -0.27, P < 0.001), and autonomous regulation (r = 0.57, P < 0.001). Outpatients reported more external (P < 0.05) and introjected (P < 0.05) regulations than inpatients. Our results suggest that patients' level of self-determination may play an important role in the adoption and maintenance of health promoting behaviors in patients with schizophrenia.

Associations between physical activity and quality of life outcomes in adults with severe obesity: a cross-sectional study prior to the beginning of a lifestyle intervention

Background

Severely obese individuals who seek lifestyle interventions have impaired quality of life (QoL). Research suggests that physical activity (PA) plays a role in weight reduction and improved health in this group, but knowledge about the association of PA with QoL outcomes is sparse and inconsistent. The aim of this study was to investigate whether a higher level of PA was independently associated with higher QoL in severely obese individuals prior to the beginning of a lifestyle intervention.

Methods

During 2010, a total of 49 severely obese individuals who began a lifestyle intervention programme in Western Norway agreed to participate in the study. Data were collected prior to the beginning of the intervention. QoL was measured by a one-item scale on life satisfaction and the SF-36, PA was measured by an accelerometer, and clinical data were collected by health staff. Linear regression analyses were used to determine the associations between PA and QoL outcomes (life satisfaction, physical functioning, and mental health), adjusting for age, gender, and body mass index (BMI).

Results

In the adjusted analyses, we found positive relationships between PA and life satisfaction (Stand. coeff. 0.39, p = 0.024) and physical functioning (Stand. coeff. 0.34, p = 0.025). There was no association between PA and mental health (Stand. coeff. 0.15, p = 0.376).

Conclusion

This study detected associations between objectively measured PA and life satisfaction as well as physical functioning in a group of severely obese individuals before they began a lifestyle intervention programme.

Temporal organization of rest defined by actigraphy data in healthy and childhood chronic fatigue syndrome children

BACKGROUND

Accumulating evidence has shown a universality in the temporal organization of activity and rest among animals ranging from mammals to insects. Previous reports in both humans and mice showed that rest bout durations followed long-tailed (i.e., power-law) distributions, whereas activity bouts followed exponential distributions. We confirmed similar results in the fruit fly, Drosophila melanogaster. Conversely, another report showed that the awakening bout durations, which were defined by polysomnography in bed, followed power-law distributions, while sleeping periods, which may correspond to rest, followed exponential distributions. This apparent discrepancy has been left to be resolved.

METHODS

Actigraphy data from healthy and disordered children were analyzed separately for two periods: time out of bed (UP period) and time in bed (DOWN period).

RESULTS

When data over a period of 24 h were analyzed as a whole, rest bouts showed a power law distribution as previously reported. However, when UP and DOWN period data were analyzed separately, neither showed power law properties. Using a newly developed strict method, only 30% of individuals satisfied the power law criteria, even when the 24 h data were analyzed. The human results were in contrast to the Drosophila results, which revealed clear power-law distributions for both day time and night time rest through the use of a strict method. In addition, we analyzed the actigraphy data from patients with childhood type chronic fatigue syndrome (CCFS), and found that they showed differences from healthy controls when their UP and DOWN data were analyzed separately.

CONCLUSIONS

These results suggested that the DOWN sleep, the bout distribution of which showed exponential properties, contributes to the production of long-tail distributions in human rest periods. We propose that separate analysis of UP and DOWN period data is important for understanding the temporal organization of activity.

Hierarchical, multi-sensor based classification of daily life activities: comparison with state-of-the-art algorithms using a benchmark dataset

Insufficient physical activity is the 4th leading risk factor for mortality. Methods for assessing the individual daily life activity (DLA) are of major interest in order to monitor the current health status and to provide feedback about the individual quality of life. The conventional assessment of DLAs with self-reports induces problems like reliability, validity, and sensitivity. The assessment of DLAs with small and light-weight wearable sensors (e.g. inertial measurement units) provides a reliable and objective method. State-of-the-art human physical activity classification systems differ in e.g. the number and kind of sensors, the performed activities, and the sampling rate. Hence, it is difficult to compare newly proposed classification algorithms to existing approaches in literature and no commonly used dataset exists. We generated a publicly available benchmark dataset for the classification of DLAs. Inertial data were recorded with four sensor nodes, each consisting of a triaxial accelerometer and a triaxial gyroscope, placed on wrist, hip, chest, and ankle. Further, we developed a novel, hierarchical, multi-sensor based classification system for the distinction of a large set of DLAs. Our hierarchical classification system reached an overall mean classification rate of 89.6% and was diligently compared to existing state-of-the-art algorithms using our benchmark dataset. For future research, the dataset can be used in the evaluation process of new classification algorithms and could speed up the process of getting the best performing and most appropriate DLA classification system.

Interventions for promoting habitual exercise in people living with and beyond cancer

BACKGROUND

The beneficial effects of regular exercise for people living with or beyond cancer are becoming apparent. However, how to promote exercise behaviour in sedentary cancer cohorts is not as well understood. A large majority of people living with or recovering from cancer do not meet exercise recommendations. Hence, reviewing the evidence on how to promote and sustain exercise behaviour is important.

OBJECTIVES

To assess the effects of interventions to promote exercise behaviour in sedentary people living with and beyond cancer and to address the following questions: Which interventions are most effective in improving aerobic fitness and skeletal muscle strength and endurance? What adverse effects are attributed to different exercise interventions? Which interventions are most effective in improving exercise behaviour amongst patients with different cancers? Which interventions are most likely to promote long-term (12 months or longer) exercise behaviour? What frequency of contact with exercise professionals is associated with increased exercise behaviour? What theoretical basis is most often associated with increased exercise behaviour? What behaviour change techniques are most often associated with increased exercise behaviour?

SEARCH METHODS

We searched the following electronic databases: Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 8, 2012), MEDLINE, EMBASE, AMED, CINAHL, PsycLIT/PsycINFO, SportDiscus and PEDro from inception to August 2012. We also searched the grey literature, wrote to leading experts in the field, wrote to charities and searched reference lists of other recent systematic reviews.

SELECTION CRITERIA

We included only randomised controlled trials (RCTs) that compared an exercise intervention with a usual care approach in sedentary people over the age of 18 with a homogenous primary cancer diagnosis.

DATA COLLECTION AND ANALYSIS

Two review authors working independently (LB and KH) screened all titles and abstracts to identify studies that might meet the inclusion criteria, or that cannot be safely excluded without assessment of the full text (e.g. when no abstract is available). All eligible papers were formally abstracted by at least two members of the review author team working independently (LB and KH) and using the data collection form. When possible, and if appropriate, we performed a fixed-effect meta-analysis of study outcomes. For continuous outcomes (e.g. cardiorespiratory fitness), we extracted the final value, the standard deviation of the outcome of interest and the number of participants assessed at follow-up in each treatment arm, to estimate standardised mean difference (SMD) between treatment arms. SMD was used, as investigators used heterogeneous methods to assess individual outcomes. If a meta-analysis was not possible or was not appropriate, we synthesised studies as a narrative.

MAIN RESULTS

Fourteen trials were included in this review, involving a total of 648 participants. Only studies involving breast, prostate or colorectal cancer were identified as eligible. Just six trials incorporated a target level of exercise that could meet current recommendations. Only three trials were identified that attempted to objectively validate independent exercise behaviour with accelerometers or heart rate monitoring. Adherence to exercise interventions, which is crucial for understanding treatment dose, is often poorly reported. It is important to note that the fundamental metrics of exercise behaviour (i.e. frequency, intensity and duration, repetitions, sets and intensity of resistance training), although easy to devise and report, are seldom included in published clinical trials.None of the included trials reported that 75% or greater adherence (the stated primary outcome for this review) of the intervention group met current aerobic exercise recommendations at any given follow-up. Just two trials reported six weeks of resistance exercise behaviour that would meet the guideline recommendations. However, three trials reported adherence of 75% or greater to an aerobic exercise goal that was less than the current guideline recommendation of 150 minutes per week. All three incorporated both supervised and independent exercise components as part of the intervention, and none placed restrictions on the control group in terms of exercise behaviour. These three trials shared programme set goals and the following behaviour change techniques: generalisation of a target behaviour; prompting of self-monitoring of behaviour; and prompting of practise. Despite the uncertainty surrounding adherence in many of the included trials, interventions caused improvements in aerobic exercise tolerance at 8 to 12 weeks (from 7 studies, SMD 0.73, 95% confidence interval (CI) 0.51 to 0.95) in intervention participants compared with controls. At six months, aerobic exercise tolerance was also improved (from 5 studies, SMD 0.70, 95% CI 0.45 to 0.94), but it should be noted that four of the five trials used in this analysis had a high risk of bias, hence caution is warranted in interpretation of results. Attrition over the course of these interventions is typically low (median 6%).

AUTHORS' CONCLUSIONS

Interventions to promote exercise in cancer survivors who report better levels of adherence share some common behaviour change techniques. These involve setting programme goals, prompting practise and self-monitoring and encouraging participants to attempt to generalise behaviours learned in supervised exercise environments to other, non-supervised contexts. However, expecting most sedentary survivors to achieve current guideline recommendations of at least 150 minutes per week of aerobic exercise is likely to be unrealistic. As with all well-designed exercise programmes in any context, prescriptions should be designed around individual capabilities, and frequency, duration and intensity or sets, repetitions, intensity or resistance training should be generated on this basis.

Objectively measured physical activity, cardiorespiratory fitness and cardiometabolic risk factors in the Health Survey for England

OBJECTIVES

The study aims to test the hypothesis that physical activity (PA) and cardiorespiratory fitness (CRF) are associated with cardiometabolic risk factors; and to test the hypothesis that CRF modifies (changes the direction and/or strength of) the associations between PA and cardiometabolic risk factors.

METHODS

PA and CRF were objectively measured in the 2008 Health Survey for England and the present study included 536 adults who completed at least 4 min of the eight-minute sub-maximal step test and wore an accelerometer for at least 10 h on at least four days. Linear regression models were fitted to examine the relationship between PA and cardiometabolic risk factors and between CRF and cardiometabolic risk factors. A test of interaction was performed to examine whether CRF modifies the associations between PA and cardiometabolic risk factors.

RESULTS

PA and CRF were associated with HDL cholesterol, the ratio of total to HDL cholesterol, glycated haemoglobin and BMI after adjustment for potential confounders. There was little evidence that CRF changed the direction or strength of associations between PA and cardiometabolic risk factors.

CONCLUSIONS

PA and CRF are associated with cardiometabolic risk factors. A larger sample is required to determine if CRF modifies associations between PA and cardiometabolic risk factors.

An evaluation of questionnaires assessing physical activity levels in youth populations

The aim of this study was to revise and organize according to recall time based criteria, questionnaires created and validated to assess the level of physical activity in children and adolescents, with the intention of enabling their proper understanding and subsequent use by nurses and health care professionals. In order to determine the questionnaires' quality, their degree of reliability and validity was the main feature to be taken into account. Thirty-eight papers were retrieved and analyzed, 31 of which were aimed at designing and validating a questionnaire intended for physical activity (PA) level assessment in youth populations (four to 19 year olds). The most widely used questionnaires were those whose recall time spans from one to seven days. In general, all questionnaires were characterized by the use of pen-and-paper format and scarce utilization of new technologies. Based upon validity and reliability criteria, in order to assess PA level in children and adolescents, nurses should use the "Children's Leisure Activities Study Survey" and the "Flemish Physical Activity Computer Questionnaire", respectively. There is a need for the validation of these tools in other languages and cultures.

Physical Activity Questionnaire for children and adolescents: English norms and cut-off points

BACKGROUND

The Physical Activity Questionnaire for Children and Adolescents (PAQ-C/-A) provides general estimates of physical activity levels. Following recent expert recommendations for using the PAQ for population surveillance, the aim of this paper was twofold: first, to describe normative PAQ data for English youth; and second, to determine a criterion-referenced PAQ-score cut-off point.

METHODS

Participants (n = 7226, 53% boys, 10-15 years) completed an anglicized version of the PAQ. Peak oxygen uptake (VO2peak ) was predicted from PACER lap count according to latest FITNESSGRAM standards and categorized into "at-risk" and "no-risk" for metabolic syndrome. ROC curves were drawn for each age-sex group to identify PAQ scores, which categorized youth into "sufficiently active" versus "low-active" groups, using cardiorespiratory fitness as the criterion-referenced standard.

RESULTS

PAQ scores were higher in boys than in girls and declined with age. Mean PAQ score was a significant, albeit relatively weak (area under the curve < 0.7) discriminator between "at-risk" and "no-risk." PAQ scores of ≥2.9 for boys and ≥2.7 for girls were identified as cut-off points, although it may be more appropriate to use lower, age-specific PAQ scores for girls of 13, 14 and 15 years (2.6, 2.4, 2.3, respectively).

CONCLUSION

The normative and criterion-referenced PAQ values may be used to standardize and categorize PAQ scores in future youth population studies.

Social anxiety in physical activity participation in patients with mental illness: a cross-sectional multicenter study

BACKGROUND

Social anxiety (SA) is a frequent comorbid condition in patients with mental illness. However, no data exist regarding SA in physical activity (PA) situations. The aim of the present study was to measure the level of self-reported SA in PA participation in patients with mental illness compared to healthy controls.

METHODS

Six hundred ninety-three patients with mental illness and 2,888 controls aged between 18 and 65 years completed the Physical Activity and Sport Anxiety Scale (PASAS). Group and gender differences in PASAS scores were tested by ANOVA and Scheffé's post hoc test.

RESULTS

After controlling for gender (P < .05), the patient group (men 40.2 ± 14.4; women 49.2 ± 17) scored higher on the PASAS compared to control group (men 30.6 ± 12.2; women 37.3 ± 13.7). Within both groups, women reported higher levels of SA compared to men.

CONCLUSIONS

Our data indicate that patients with mental illness reported higher levels of SA in PA situations compared to healthy control subjects. Health professionals should consider SA when trying to improve outcome and adherence of patients with mental illness to PA interventions.

To total amount of activity….. and beyond: perspectives on measuring physical behavior

The aim of this paper is to describe and discuss some perspectives on definitions, constructs, and outcome parameters of physical behavior. The paper focuses on the following constructs: Physical activity and active lifestyle vs. sedentary behavior and sedentary lifestyle; Amount of physical activity vs. amount of walking; Detailed body posture and movement data vs. overall physical activity data; Behavioral context of activities; Quantity vs. quality; Physical behavior vs. physiological response. Subsequently, the following outcome parameters provided by data reduction procedures are discussed: Distribution of length of bouts; Variability in bout length; Time window; Intensity and intensity threshold. The overview indicates that physical behavior is a multi-dimensional construct, and it stresses the importance and relevance of constructs and parameters other than total amount of physical activity. It is concluded that the challenge for the future will be to determine which parameters are most relevant, valid and responsive. This is a matter for physical behavior researchers to consider, that is critical to multi-disciplinary collaboration.

The long-term effectiveness of need-supportive physical activity counseling compared with a standard referral in sedentary older adults

This study compared the long-term effectiveness of three physical activity counseling strategies among sedentary older adults: a 1-contact referral (REFER), a 1-contact individualized walking program (WALK), and multiple-contact, individually tailored, and need-supportive coaching based on the self-determination theory (COACH). Participants (n = 442) completed measurements before (pretest), immediately after (posttest), and 1 yr after (follow-up test) a 10-wk intervention. Linear mixed models demonstrated significant time-by-condition interaction effects from pre- to posttest. More specifically, WALK and COACH yielded larger increases in daily steps and self-reported physical activity than REFER. Similarly, self-reported physical activity increased more from pre- to follow-up test in WALK and COACH compared with REFER. Autonomous motivation mediated the effect of perceived need-support on physical activity, irrespective of counseling strategy. These results demonstrate the long-term effectiveness of both a 1-contact individualized walking program and a more time-consuming, need-supportive coaching, especially in comparison with a standard referral to local opportunities.

Does a patient's physical activity predict recovery from an episode of acute low back pain? A prospective cohort study

Background

Advice to remain active and normalisation of activity are commonly prescribed in the management of low back pain (LBP). However, no research has assessed whether objective measurements of physical activity predict outcome and recovery in acute low back pain.

Method

The aims of this study were to assess the predictive relationship between activity and disability at 3 months in a sub-acute LBP population. This prospective cohort study recruited 101 consenting patients with sub-acute LBP (< 6 weeks) who completed the Roland Morris Disability Questionnaire (RMDQ), the Visual Analogue Scale, and resumption of full ‘normal’ activity question (Y/N), at baseline and 3 months. Physical activity was measured for 7 days at both baseline and at 3 months with an RT3 accelerometer and a recall questionnaire.

Results

Observed and self-reported measures of physical activity at baseline and change in activity from baseline to 3 months were not independent predictors of RMDQ (p > 0.05) or RMDQ change (p > 0.05) over 3 months. A self-report of a return to full ‘normal’ activities was significantly associated with greater RMDQ change score at 3 months (p < 0.001). Paired t-tests found no significant change in activity levels measured with the RT3 (p = 0.57) or the recall questionnaire (p = 0.38) from baseline to 3 months.

Conclusions

These results question the predictive role of physical activity in LBP recovery, and the assumption that activity levels change as LBP symptoms resolve. The importance of a patient’s perception of activity limitation in recovery from acute LBP was also highlighted.

Trial registration

Clinical Trial Registration Number, ACTRN12609000282280

Estimating relative intensity using individualized accelerometer cutpoints: the importance of fitness level

Background

Accelerometer cutpoints based on absolute intensity may under or overestimate levels of physical activity due to the lack of consideration for an individual’s current fitness level. The purpose of this study was to illustrate the interindividual variability in accelerometer activity counts measured at relative intensities (40 and 60% heart rate reserve (HRR)) and demonstrate the differences between relative activity counts between low, moderate and high fitness groups.

Methods

Seventy-three subjects (38 men, 35 women) with a wide range of cardiorespiratory fitness (maximal oxygen consumption (VO_2max): 27.9 to 58.5 ml · kg^-1 · min^-1), performed a submaximal exercise test with measures of heart rate (HR) and accelerometer activity counts. Linear regression equations were developed for each subject to determine accelerometer activity counts for moderate and vigorous intensity physical activity corresponding to 40% and 60% of HRR. Interindividual variability of activity counts between subjects at both 40% and 60% of HRR was demonstrated by plotting values using a box and whisker plot. To examine the difference between absolute and relative activity cutpoints, subjects were categorized into 3 fitness groups based on metabolic equivalents (MET) (<10 MET, 10–13 MET, >13 MET).

Results

At 40 and 60% of HRR, activity counts ranged from 1455–7520, and 3459–10066 counts · min^-1, respectively. Activity counts at 40% HRR (3385 ± 850, 4048 ± 1090, and 5037 ± 1019 counts · min^-1) and 60% HRR (5159 ± 765, 5995 ± 1131 and 7367 ± 1374 counts · min^-1) significantly increased across fitness groups (<10 MET, 10–13 MET, and >13 MET, respectively).

Conclusion

This study revealed interindividual variability in activity counts at relative moderate (40% HRR) and vigorous (60% HRR) intensities, while fitness level was shown to have a significant influence on relative activity counts measured at these intensities. Individualizing activity count cutpoints may be more representative of an individual’s PA level relative to their fitness capacity, compared to absolute activity count cutpoints.

A review of physical activity correlates in patients with bipolar disorder

BACKGROUND

Existing studies do suggest that physical activity interventions may be feasible and have a role in promoting mental and physical health in patients with bipolar disorder. The present review evaluates systematically quantitative studies of correlates of physical activity in patients with bipolar disorder.

METHODS

We searched EMBASE, PsycINFO, PubMed, and CINAHL from their inception, combining the medical subject headings 'bipolar disorder' or 'mania' or 'manic depression' with 'physical activity' or 'physical inactivity' or 'exercise'.

RESULTS

Out of 40 potentially eligible studies, 11 papers evaluating 26 correlates were included. Correlates that were associated with lower physical activity participation were lower self-efficacy, presence of medical co-morbidity, lower educational status and social isolation. Less consistent variables associated with lower physical activity participation included higher BMI, older age, financial strains, not being connected to a health care service, and minority ethnicity. A larger study sample size was related to a higher proportion of significant associations (p=0.04). Current gaps in literature which need to be examined more in detail are the role of psychiatric symptoms, environmental and policy-level factors.

LIMITATIONS

The diversity of physical activity measures and subject samples prevented us to perform a meta-analysis.

CONCLUSIONS

All significant correlates should be confirmed in prospective studies and interventions to improve the modifiable variables should be developed and evaluated. The reviewed data also demonstrate that validation studies on physical activity measurements are highly needed.