Measuring physical activity in midlife, older, and minority women: issues from an expert panel

Longitudinal Assessment of Physical Activity and Cognitive Outcomes Among Women at Midlife

IMPORTANCE

The increasing prevalence of cognitive decline, impairment, and dementia spurs intense interest in cognitive preservation strategies.

OBJECTIVE

To explore the longitudinal association between physical activity (PA) and cognitive performance among women at midlife.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study is an analysis from the Study of Women's Health Across the Nation. Enrollment occurred from 1996 through 1997, and follow-up extended into 2017. Included individuals were those who had undergone cognitive measures during the first 3 cognitive test visits and had at least 1 additional cognitive measurement. Stroke prior to baseline was an exclusion, and observations were censored for subsequent stroke. Data were analyzed from June 2018 through August 2019.

EXPOSURES

Engaging in sport or exercise PA (self-reported).

MAIN OUTCOMES AND MEASURES

The Symbol Digit Modalities Test (SDMT) was used to assess cognitive processing speed. The East Boston Memory Test-Delayed (EBMT-D) was used to measure verbal episodic memory. The digit span backwards (DSB) test was used to evaluate working memory.

RESULTS

Among 1718 women with a median (range) observation time of 11.9 (0.60-13.5) years, the mean (SD) baseline age was 45.7 (2.5) years. From baseline through age 61 years, mean change in SDMT score was -0.20 annually (95% CI, -0.26 to -0.15; P < .001). After age 61 years, the mean change in SDMT was -0.51 yearly (95% CI, -0.54 to -0.41; P < .001). Beginning at age 58 years of the mean change in EBMT was -0.03 yearly (95% CI, -0.04 to -0.02; P < .001). Starting at age 61 years, mean (SD) change in DSB was -0.03 annually (95% CI, -0.04 to -0.01; P = .001). When adjusted for attrition and practice effect, PA was associated with higher concurrent SDMT and EBMT scores and a smaller decrease in SDMT score. For each unit increment in PA, there was a 0.36 increment in concurrent SDMT score (95% CI, 0.14 to 0.59; P = .002) and a 0.10 increment in concurrent EBMT score (95% CI, 0.05 to 0.15; P < .001). Greater PA was associated with a smaller annual mean decrease in SDMT score (0.06 yearly; 95% CI, 0.02 to 0.09; P = .001). After additional adjustment for demographic characteristics, menopause symptoms, hormone therapy use, and the presence of diabetes and hypertension, PA was not associated with trajectories (ie, levels or slopes) of any cognitive outcome.

CONCLUSIONS AND RELEVANCE

This cohort study found no association between greater PA levels and cognitive outcomes among women in midlife, unlike cohort studies that begin observations at later ages, which may be associated with confounding by reverse causation (ie, cognitive decline associated with an outcome of lower PA levels).

Rationale and Design of the Women's Health And Daily Experiences Project: Protocol for an Ecological Momentary Assessment Study to Identify Real-Time Predictors of Midlife Women's Physical Activity

BACKGROUND

Midlife women are at an elevated risk for cardiovascular disease (CVD) and associated mortality. Those who have additional risk conditions such as obesity or hypertension report specific barriers to engaging in cardioprotective behaviors such as physical activity (PA). Considerable effort has been devoted to understanding PA determinants and designing interventions for midlife women, although with suboptimal success, as increasing PA could meaningfully attenuate CVD risk. An updated approach to understanding PA among midlife women could improve upon existing resources by focusing on novel psychosocial influences on PA in this population (ie, body satisfaction, social interactions, social comparisons, mood state) and within-person relations between these influences and PA in the natural environment.

OBJECTIVE

The overarching goal of Project WHADE (Women's Health And Daily Experiences) is to use an ecological momentary assessment (EMA) approach to capture ecologically valid relations between midlife women's psychosocial experiences and PA as they engage in their normal daily activities. The primary aim of the study is to identify within-person psychosocial predictors of variability in PA (ie, experiences associated with higher vs lower PA for a given individual).

METHODS

Midlife women (aged 40-60 years) with one or more additional risk markers for CVD (eg, hypertension) will be recruited from primary care clinics and the general community (target n=100). Eligible women will complete an initial survey and a face-to-face baseline session before engaging in a 10-day EMA protocol. Psychosocial experiences will be assessed using a brief self-report via a smartphone 5 times per day, and PA will be assessed throughout waking hours using a research-grade monitor. Participants will return for a brief exit interview at the end of 10 days. Multilevel models that address the nested structure of EMA data will be used to evaluate the study aims.

RESULTS

Recruitment and enrollment are ongoing, and a total of 75 women have completed the protocol to date. Data collection is expected to be completed in Fall 2020.

CONCLUSIONS

Project WHADE is designed to identify naturally occurring psychosocial experiences that predict short-term variability in midlife women's PA. As such, the results of this study should advance the current understanding of PA among midlife women by providing further insight into within-person psychosocial influences on PA in this group. In the future, this information could help inform the design of interventions for this population.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/19044.

Communicating and Assessing Physical Activity: Outcomes From Cognitive Interviews With Low-Income Adults

OBJECTIVE

This investigation sought to identify the physical activity (PA) terms and concepts that are best understood by low-income adults.

DESIGN

This was a cross-sectional study using semistructured cognitive interviews that employed retrospective verbal probing techniques.

SETTING

Interviews were conducted in Expanded Food and Nutrition Education Program (EFNEP) sites in New Jersey, Tennessee, and Washington.

PARTICIPANTS

A convenience sample of 57 adults participating in or eligible for participation in EFNEP.

PHENOMENON OF INTEREST

Participants' interpretations and conceptualizations of PA concepts and terms.

ANALYSIS

Template and constant comparative analysis.

RESULTS

Participants interpreted many PA terms and concepts in unintended ways. Exercise was the term that came closest to conveying moderate to vigorous PA. Terms used to describe muscle-strengthening activities were mostly understood. Intentional engagement in extra activities was difficult for participants to conceptualize despite multiple tested wordings; making small changes to be active came closest to conveying this concept. Participants' comprehension of the PA terms differed by their PA and literacy levels.

CONCLUSIONS AND IMPLICATIONS

Nutrition educators should be mindful of the terminologies they used in communicating messages and assessing PA behaviors to EFNEP participants or similar populations.

Psychosocial Correlates and Outcomes of Physical Activity Among Latinos: A Review

Despite the many physical and psychological benefits of physical activity, it is well documented that the general population does not engage in sufficient leisure time physical activity to accrue such benefits. In the Latino population the situation is even more dire. This review focuses on studies of the relationship between physical activity and psychosocial correlates and outcomes in Latino men and women. It was demonstrated that the majority of studies with Latino participants examined constructs similar to those studied in the general population, namely, self-efficacy, social support, and perceived barriers. The existing literature is discussed in terms of (a) the lack of information on the psychological/psychosocial constructs of physical activity for Latinos, (b) the lack of intervention research, (c) reporting results of studies as “minority correlates,” (d) the importance of Latino subcultures and the heterogeneity of Latinos, and (e) the measurement of physical activity.

Visual Methods in the Assessment of Diet Intake in Mexican American Women

Assessment of dietary intake is based largely on self-report or use of biomarkers. However, neither self-report nor biomarkers inform nurses of patterns in dietary intake in the context of gender, culture, and ethnicity. This article describes the relevance of visual methods focusing on the context of dietary intake in Mexican American women, illustrated by a formative study. A qualitative, descriptive, methodological design incorporating photo elicitation was used. The sample consisted of 7 Mexican American women, who took photographs of their food intake, food preparation, and context of food consumption, such as family gatherings, which were then described by the women. Data included participant photographs, the descriptions of why each image was obtained, and stories about the photographs. Visual methods were found to be a relevant and important addition to traditional dietary assessment methods, to enhance gender, cultural, and contextually relevant assessment of dietary intake in Mexican American women.

Assessment of Physical Activity of People with Visual Impairments and Individuals who Are Sighted Using the International Physical Activity Questionnaire and Actigraph

Introduction

The aim of this study was to analyze the results of walking assessments and total energy expenditure based on a questionnaire and accelerometer measurements among people with visual impairments and those who are sighted.

Methods

The study included 25 persons with visual impairments and 25 individuals who are sighted, age 32.3 ± 5.3 years. A weekly measurement of physical activity using the International Physical Activity Questionnaire long form (IPAQ-LF) and accelerometer GTX3 ActiGraph was conducted.

Results

It was demonstrated that visual impairment affects walking ability, insofar as it reduces the number of steps taken in a day ( p ≤ .05) (ActiGraph); it does not, however, differentiate physical activity level (IPAQ-LF). Moreover, there has been observed a lower energy expenditure in people with visual impairments in relation to intensive ( p ≤ .01) and moderate-level ( p ≤ .001) physical activity. In the group of people with visual impairments, a correlation ( p ≤ .05) was observed between the energy expenditure associated with walking (IPAQ-LF) and the total weekly energy expenditure associated with physical activity (ActiGraph). Also, a correlation ( p ≤ .05) was observed between the total weekly energy expenditure associated with physical activity in the IPAQ-LF and ActiGraph.

Discussion

Regardless of the method used to measure physical activity, on average, participants with visual impairments took a smaller number of steps than participants who were sighted. However, the average number of steps taken by participants with visual impairments was much higher than the 3,500–5,000 steps recommended as healthy for a person with disabilities.

Implications for practitioners

IPAQ-LF and ActiGraph are effective methods of monitoring physical activity in persons with visual impairments, and may be used in supporting activities that promote taking up physical activity.

The association between daily steps and health, and the mediating role of body composition: a pedometer-based, cross-sectional study in an employed South African population

BACKGROUND

Walking is recognized as an easily accessible mode of physical activity and is therefore supported as a strategy to promote health and well-being. To complement walking, pedometers have been identified as a useful tool for monitoring ambulatory physical activity, typically measuring total steps/day. There is, however, little information concerning dose-response for health outcomes in relation to intensity or duration of sustained steps. We aimed to examine this relationship, along with factors that mediate it, among employed adults.

METHODS

A convenience sample, recruited from work-site health risk screening (N = 312, 37 ± 9 yrs), wore a pedometer for at least three consecutive days. Steps were classified as "aerobic" (≥100 steps/minute and ≥10 consecutive minutes) or "non-aerobic" (<100 steps/minute and/or <10 consecutive minutes). The data were sub-grouped according to intensity-based categories i.e. "no aerobic activity", "low aerobic activity" (1-20 minutes/day of aerobic activity) and "high aerobic activity" (≥21 minutes/day of aerobic activity), with the latter used as a proxy for current PA guidelines (150-minutes of moderate-intensity PA per week). Health outcomes included blood pressure, body mass index, percentage body fat, waist circumference, blood cholesterol and blood glucose. Analysis of covariance, adjusting for age, gender and total steps/day were used to compare groups according to volume and intensity-based steps categories. A further analysis compared the mediation effect of body fat estimates (percentage body fat, body mass index and waist circumference) on the association between steps and health outcomes, independently.

RESULTS

Average steps/day were 6,574 ± 3,541; total steps/day were inversely associated with most health outcomes in the expected direction (p < 0.05). The "no aerobic activity" group was significantly different from the "low aerobic activity" and "high aerobic activity" in percentage body fat and diastolic blood pressure only (P < 0.05). Percentage body fat emerged as the strongest mediator of the relationship between steps and outcomes, while body mass index showed the least mediation effect.

CONCLUSION

The study provides a presentation of cross-sectional pedometer data that relate to a combination of intensity and volume-based steps/day and its relationship to current guidelines. The integration of volume, intensity and duration of ambulatory physical activity in pedometer-based messages is of emerging relevance.

Validation of a Computerized Use of Time Recall for Activity Measurement in Advanced-Age Adults

Background:

The Multimedia Activity Recall for Children and Adults (MARCA) is a computerized recall instrument that records use of time during 24 hr the previous day and has been developed to address limitations of current self-report physical activity measures for those in advanced age.

Methods:

Test–retest reliability and convergent validity of the adult MARCA were assessed in a sample of 45 advanced-age adults (age 84.9SD ±1.62 yr) as a subsample of the Life and Living in Advanced-Age Cohort Study New Zealand (LiLACS NZ). Test–retest methods required participants to recall the previous day’s activity using the MARCA twice within the same day. Convergent validity was assessed against accelerometry.

Results:

Test–retest reliability was high, with ICCs greater than .99 for moderate to vigorous physical activity (MVPA) and physical activity level (PAL). Compared with accelerometry, the MARCA demonstrated validity comparable to other self-report instruments with Spearman’s coefficients of .34 and .59 for time spent in nonsedentary physical activity and PAL.

Conclusion:

The MARCA is a valid and reliable self-report tool for physical activity behaviors in advanced-age adults.

Nonexercise physical activity and inflammatory and oxidative stress markers in women

BACKGROUND

Leisure time exercise has been linked to lower circulating levels of inflammatory markers. Few studies have examined the association of nonexercise physical activity with markers of inflammation and oxidative stress.

METHODS

This cross-sectional analysis included 1005 Chinese women aged 40-70 years. Usual physical activity was assessed through in-person interviews using a validated physical activity questionnaire. Plasma proinflammatory cytokines and urinary F2-isoprostanes were measured. Multivariable linear models were used to evaluate the association of inflammatory and oxidative stress markers with nonexercise physical activity and its major components.

RESULTS

Nonexercise physical activity accounted for 93.8% of overall physical activity energy expenditure. Levels of nonexercise physical activity were inversely associated with circulating concentrations of interleukin (IL)-6 (Ptrend=0.004), IL-1β (Ptrend=0.03) and tumor necrosis factor-alpha (TNF-α) (Ptrend=0.01). Multivariable-adjusted concentrations of these cytokines were 28.2% for IL-6, 22.1% for IL-1β, and 15.9% for TNF-α lower in the highest quartile of nonexercise physical activity compared with the lowest quartile. Similar inverse associations were found for two major components of nonexercise physical activity, walking and biking for transportation, and household activity. No significant associations were observed between nonexercise physical activity and oxidative stress markers.

CONCLUSION

Daily nonexercise physical activity is associated with lower levels of systemic inflammation. This finding may have important public health implications because this type of activity is the main contributor to overall physical activity among middle-aged and elderly women.

Consistently high sports/exercise activity is associated with better sleep quality, continuity and depth in midlife women: the SWAN sleep study

STUDY OBJECTIVES

To examine relationships between different physical activity (PA) domains and sleep, and the influence of consistent PA on sleep, in midlife women.

DESIGN

Cross-sectional.

SETTING

Community-based.

PARTICIPANTS

339 women in the Study of Women's Health Across the Nation Sleep Study (52.1 ± 2.1 y).

INTERVENTIONS

None.

MEASUREMENTS AND RESULTS

Sleep was examined using questionnaires, diaries and in-home polysomnography (PSG). PA was assessed in three domains (Active Living, Household/Caregiving, Sports/Exercise) using the Kaiser Physical Activity Survey (KPAS) up to 4 times over 6 years preceding the sleep assessments. The association between recent PA and sleep was evaluated using KPAS scores immediately preceding the sleep assessments. The association between the historical PA pattern and sleep was examined by categorizing PA in each KPAS domain according to its pattern over the 6 years preceding sleep assessments (consistently low, inconsistent/consistently moderate, or consistently high). Greater recent Sports/Exercise activity was associated with better sleep quality (diary "restedness" [P < 0.01]), greater sleep continuity (diary sleep efficiency [SE; P = 0.02]) and depth (higher NREM delta electroencephalographic [EEG] power [P = 0.04], lower NREM beta EEG power [P < 0.05]), and lower odds of insomnia diagnosis (P < 0.05). Consistently high Sports/Exercise activity was also associated with better Pittsburgh Sleep Quality Index scores (P = 0.02) and higher PSG-assessed SE (P < 0.01). Few associations between sleep and Active Living or Household/Caregiving activity (either recent or historical pattern) were noted.

CONCLUSION

Consistently high levels of recreational physical activity, but not lifestyle- or household-related activity, are associated with better sleep in midlife women. Increasing recreational physical activity early in midlife may protect against sleep disturbance in this population.

Measuring Physical Activity in Older Adults with and without Early Stage Alzheimer's Disease

We compared subjective reports of physical activity with objective measures of physical fitness including cardiorespiratory capacity, body composition, and physical performance in 146 older adults with and without early stage Alzheimer's disease (ESAD). Respondents reported primarily unstructured and low-intensity activities, including walking and housework. Individuals with ESAD participated in fewer and lower intensity physical activities than those without ESAD. In those without ESAD, housework was related to lower body mass index, leisure walking was related to faster speed on a timed walking test, and participation in sports was related to higher peak oxygen intake. In individuals with ESAD, reported physical activities did not predict any of the physical fitness, body composition, or physical performance measures. We conclude that measures of physical activity require expansion of unstructured and low intensity activities to improve sensitivity in sedentary populations, especially in older adults with ESAD.

A framework for understanding modifications to measures for diverse populations

OBJECTIVE

Research on health disparities and determinants of health disparities among ethnic minorities and vulnerable older populations necessitates use of self-report measures. Most established instruments were developed on mainstream populations and may need adaptation for research with diverse populations. Although information is increasingly available on various problems using these measures in diverse groups, there is little guidance on how to modify the measures. A framework of issues to consider when modifying measures for diverse populations is presented.

METHODS

The authors describe reasons for considering modifications, the types of information that can be used as a basis for making modifications, and the types of modifications researchers have made. Recommendations are made to test modified measures to assure their appropriateness, and suggestions are provided on reporting modifications in publications using the measures.

DISCUSSION

The issues open a dialogue about what appropriate guidelines would be for researchers adapting measures in studies of ethnically diverse populations.

The experience of physical activity and the transition to retirement: a systematic review and integrative synthesis of qualitative and quantitative evidence

BACKGROUND

The transition to retirement has been recognised as a critical turning point for physical activity (PA). In an earlier systematic review of quantitative studies, retirement was found to be associated with an increase in recreational PA but with a decrease in PA among retirees from lower occupational groups. To gain a deeper understanding of the quantitative review findings, qualitative evidence on experiences of and views on PA around the transition to retirement was systematically reviewed and integrated with the quantitative review findings.

METHOD

19 electronic databases were searched and reference lists were checked, citations tracked and journals hand-searched to identify qualitative studies on PA around the transition to retirement, published between January 1980 and August 2010 in any country or language. Independent quality appraisal, data extraction and evidence synthesis were carried out by two reviewers using a stepwise thematic approach. The qualitative findings were integrated with those of the existing quantitative systematic review using a parallel synthesis approach.

RESULTS

Five qualitative studies met the inclusion criteria. Three overarching themes emerged from the synthesis of these studies: these related to retirees' broad concepts of PA, the motives for and the challenges to PA in retirement. Integrative synthesis of the qualitative findings with the quantitative evidence offered several potential explanations for why adults might engage in more recreational PA after the transition to retirement. These included expected health benefits, lifelong PA patterns, opportunities for socialising and personal challenges, and the desire for a new routine. A decrease in PA among retirees from lower occupational groups might be explained by a lack of time and a perceived low personal value of recreational PA.

CONCLUSIONS

To encourage adoption and maintenance of PA after retirement, interventions should promote health-related and broader benefits of PA. Interventions for retirees from lower occupational groups should take account of busy post-retirement lifestyles and the low personal value that might be attributed to recreational PA. Future research should address predictors of maintenance of recreational PA after the transition to retirement, the broader benefits of PA, and barriers to PA among retirees from lower occupational groups.

The association between objectively measured physical activity and knee structural change using MRI

OBJECTIVES

This study describes the longitudinal association between objectively assessed physical activity (PA) and knee structural change measured using MRI.

METHODS

405 community-dwelling adults aged 51-81 years were measured at baseline and approximately 2.7 years later. MRI of the right knee at baseline and follow-up was performed to evaluate bone marrow lesions (BMLs), meniscal pathology, cartilage defects, and cartilage volume. PA was assessed at baseline by pedometer (steps/day).

RESULTS

Doing ≥10 000 steps/day was associated with BML increases (RR 1.97, 95% CI 1.19 to 3.27, p=0.009). Participants doing ≥10 000 steps/day had a 1.52 times (95% CI 1.05 to 2.20, p=0.027) greater risk of increasing meniscal pathology score, which increased to 2.49 (95% CI 1.05 to 3.93, p=0.002) in those with adverse meniscal pathology at baseline. Doing ≥10 000 steps/day was associated with a greater risk of increasing cartilage defect score in those with prevalent BMLs at baseline (RR 1.36, 95% CI 1.03 to 1.69, p=0.013). Steps/day was protective against volume loss in those with more baseline cartilage volume but led to increased cartilage loss in those with less baseline cartilage volume. (p=0.046 for interaction).

CONCLUSIONS

PA was deleteriously associated with knee structural change, especially in those with pre-existing knee structural abnormalities. This suggests individuals with knee abnormalities should avoid doing ≥10 000 steps/day. Alternatives to weight-bearing activity may be needed in order to maintain PA levels required for other aspects of health.

Promoting physical activity in patients with colon adenomas: a randomized pilot intervention trial

BACKGROUND

Physical activity decreases risk of colon polyps and colon cancer and might reduce risk of colon cancer recurrence. Focusing on recent calls for translation of epidemiologic evidence into clinical care, our pilot study delivered an evidence-based physical activity intervention in adults with polyps, who are thus at elevated risk of developing colon cancer. The objective was to evaluate change in physical activity, measured by steps per day and minutes of moderate/vigorous physical activity.

METHODS

Sixteen adults with adenomas detected and removed at screening colonoscopy were recruited to a 12-week physical activity intervention. Participants were randomized to receive a standard (30 minutes/day) or high (60 minutes/day) walking program. Physical activity was measured via blinded pedometer and accelerometer at baseline and follow-up. Intervention messages focused on self-monitoring using pedometers and overcoming barriers to engaging in physical activity.

RESULTS

Participants in both arms significantly increased objectively measured minutes of moderate/vigorous physical activity over the course of the intervention. Both arms exceeded the intervention goal, but there was not a significant difference between arms at follow-up. Results were similar for pedometer measured physical activity, with a significant overall increase in steps/day from baseline to follow-up, but no between arm difference in change.

CONCLUSION

Simple interventions of minimal contact time focusing on walking can significantly increase physical activity in individuals at increased risk of developing colon cancer.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01476631.

Relationship between accelerometer-based measures of physical activity and the Yale Physical Activity Survey in adults with arthritis

OBJECTIVE

To evaluate the correlation between the Yale Physical Activity Survey (YPAS) scores and objective accelerometer measures of time spent in light intensity physical activities, moderate to vigorous intensity physical activities, and moderate to vigorous activities in bouts lasting at least 10 minutes.

METHODS

This study analyzed baseline data from 171 persons with rheumatoid arthritis (RA) and 139 persons with osteoarthritis (OA) in a randomized clinical trial (Increasing Motivation for Physical Activity in Arthritis Clinical Trial). Persons fulfilling the 1987 American College of Rheumatology criteria for RA and persons with symptomatic radiologic knee OA (Kellgren/Lawrence class ≥2) wore an accelerometer for 7 days, then responded to the YPAS questionnaire and questions regarding demographics (age, sex, and race) and health factors (body mass index, disease status [Health Assessment Questionnaire/Western Ontario and McMaster Universities Osteoarthritis Index], comorbidities, pain, and function). Spearman's correlation coefficients were estimated between each YPAS summary measure and accelerometer measures.

RESULTS

In the RA participants, the strongest correlation was between the YPAS activity dimensions summary index (Y-ADSI) and average daily minutes of bouted moderate/vigorous activity (r = 0.51). Additionally, the Y-ADSI correlated significantly with both objectively measured average daily accelerometer counts (r = 0.45) and average daily minutes of moderate/vigorous activity (r = 0.43). For OA participants, a similar pattern emerged: the Y-ADSI had significant correlations with average daily minutes of bouted moderate/vigorous activity (r = 0.36), average daily minutes of moderate/vigorous activity (r = 0.31), and average daily counts (r = 0.24).

CONCLUSION

For both the RA and OA groups, the Y-ADSI had the strongest significant correlations with objectively measured physical activity, which supports Y-ADSI use as a tool for clinical applications and in rheumatology research.

Mujeres en accion: design and baseline data

The majority of programs designed to promote physical activity in older Hispanic women includes few innovative theory-based interventions that address cultural relevant strategies. The purpose of this report is to describe the design and baseline data for Mujeres en Accion, a physical activity intervention to increase regular physical activity, and cardiovascular health outcomes among older Hispanic women. Mujeres en Accion [Women in Action for Health], a 12 month randomized controlled trial to evaluate the effectiveness of a social support physical activity intervention in midlife and older Hispanic women. This study tests an innovative intervention, Mujeres en Accion, and includes the use of a theory-driven approach to intervention, explores social support as a theoretical mediating variable, use of a Promotora model and a Community Advisory group to incorporate cultural and social approaches and resources, and use of objective measures of physical activity in Hispanic women.

Assessment of Physical Activity in Older People With and Without Cognitive Impairment

The purpose of this study was to validate a new interview-administered physical activity questionnaire (Assessment of Physical Activity in Frail Older People; APAFOP) in older people with and without cognitive impairment. The authors assessed feasibility, validity, and test–retest reliability in 168 people (n= 78 with,n= 88 without cognitive impairment). Concurrent validity was assessed against an inertia-based motion sensor and an established questionnaire. Sensitivity to change was tested in an ongoing study in patients with mild to moderate dementia (n= 81). Assessment of physical activity by the APAFOP and the motion sensor correlated well in the total sample (TS; p= .705), as well as in the subsamples with cognitive impairment (CI;p= .585) and without CI (p= .787). Excellent feasibility with an acceptance rate of 100%, test–retest reliability (intraclass correlation coefficients ranging from .973 (TS) to .975 (CI) to .966 (no CI), and sensitivity to change (effect sizes: 0.35–1.47) were found in both subsamples.

Late life function and disability instrument in African American women: function component

Obesity, age, and comorbidity can lead to limitations in physical function, especially in middle aged, community-dwelling, African American women. To determine the clinical implications of limitations in physical function, instruments that assess physical function need to be tested in this population. The purpose of the authors in this secondary analysis was to report the internal consistency and validity of the Physical Function component of the Late Life Function and Disability Instrument in middle-aged, community-dwelling, African American women. In 2006, 126 community-dwelling African American women completed the Physical Function component, the Physical Activity Scale for the Elderly, and the 6 Minute Walk Test at baseline. Results indicated Cronbach's alphas were excellent (all >.92) for the Physical Function component and the three subscales. The Physical Function component correlated directly with the Physical Activity Scale for the Elderly (r = .37, p < .01) and the 6 Minute Walk Test (r = .36, p < .01) but was inversely correlated with age (r = -.42, p < .01) and comorbidity (r = -.35, p < .01). However, obesity was not correlated (r = -.11, p > .05). A three-factor structure of the Physical Function component was confirmed. Thus, the Physical Function component was a reliable and valid measure to screen African American women who were at risk for function limitations. Future recommendations are discussed.

The association between social factors and physical activity among low-income adults living in public housing

OBJECTIVES

We sought to examine the association between structural, functional, and normative social factors and physical activity among urban, low-income, racially/ethnically diverse adults.

METHODS

We conducted a baseline cross-sectional survey among residents of 12 low-income housing communities in metropolitan Boston, Massachusetts. Participants were also asked to wear a pedometer for 5 days. We analyzed complete data from 1112 residents (weighted n = 1635).

RESULTS

Residents with smaller social networks were significantly less physically active than were residents with larger social networks (b = -1503.7; P = .01) and residents with conflicting demands were more active than were residents with none (b = 601.6; P = .01), when we controlled for employment status, gender, poverty level, current health status, age, and perceived safety. Social networks were most strongly associated with physical activity among Hispanics and younger residents (aged 18-35 years).

CONCLUSIONS

These findings indicate that social factors, including social networks and role-related conflicting demands, may be important drivers of physical activity among low-income populations. Researchers and practitioners should consider social factors in developing multilevel physical activity interventions for this population.

Reliability and validity of an internet-based questionnaire measuring lifetime physical activity

Lifetime exposure to physical activity is an important construct for evaluating associations between physical activity and disease outcomes, given the long induction periods in many chronic diseases. The authors' objective in this study was to evaluate the measurement properties of the Lifetime Physical Activity Questionnaire (L-PAQ), a novel Internet-based, self-administered instrument measuring lifetime physical activity, among Canadian men and women in 2005-2006. Reliability was examined using a test-retest study. Validity was examined in a 2-part study consisting of 1) comparisons with previously validated instruments measuring similar constructs, the Lifetime Total Physical Activity Questionnaire (LT-PAQ) and the Chasan-Taber Physical Activity Questionnaire (CT-PAQ), and 2) a priori hypothesis tests of constructs measured by the L-PAQ. The L-PAQ demonstrated good reliability, with intraclass correlation coefficients ranging from 0.67 (household activity) to 0.89 (sports/recreation). Comparison between the L-PAQ and the LT-PAQ resulted in Spearman correlation coefficients ranging from 0.41 (total activity) to 0.71 (household activity); comparison between the L-PAQ and the CT-PAQ yielded coefficients of 0.58 (sports/recreation), 0.56 (household activity), and 0.50 (total activity). L-PAQ validity was further supported by observed relations between the L-PAQ and sociodemographic variables, consistent with a priori hypotheses. Overall, the L-PAQ is a useful instrument for assessing multiple domains of lifetime physical activity with acceptable reliability and validity.

Evaluation of physical activity measures used in middle-aged women

PURPOSE

To evaluate the reliability and validity of five commonly used physical activity questionnaires (PAQ) in women aged 45-65 yr with varying physical activity (PA) levels.

METHODS

Data were obtained from the Evaluation of Physical Activity Measures in Middle-aged Women (PAW) Study and included 66 women (aged 52.6 +/- 5.4 yr). PAQ evaluated include Modifiable Activity Questionnaire (past week and past month version), Nurses' Health Study PAQ, Active Australia Survey, and Women's Health Initiative PAQ. Intraclass correlation coefficients (ICC) between administrations of the PAQ were used to assess test-retest reliability. Spearman rank-order correlation coefficients were used to examine the associations of PA and physical fitness data with PAQ summary estimates.

RESULTS

Accelerometer-determined median (25th, 75th percentiles) times (min.d) spent in moderate-lifestyle [760-1951 counts (ct)], moderate-walk (1952-5724 ct), vigorous (> or =5725 ct), and combined moderate and vigorous PA (MVPA > or = 1952 ct) during the 35 d of observation were 66.0 (51.2, 81.3), 23.1 (14.1, 34.6), 0.4 (0.0, 2.3), and 24.3 (15.9, 41.6) min, respectively. The PAQ were shown to be reproducible and relatively stable over time (ICC = 0.32 to 0.91) and were associated with total counts per day (ct.d, 0.46 to 0.60, all P < 0.001), and most were associated with many facets of physical fitness, including cardiorespiratory fitness (0.36 to 0.46, P < 0.01), body composition (-0.27 to -0.34, P < 0.05), and muscular fatigue (-0.25 to -0.44, P < 0.05).

CONCLUSIONS

The PAQ evaluated in this study were shown to be reliable and associated with PA and physical fitness measures. Current findings support the utility of these PAQ for PA assessment in research studies of middle-aged women.

Effects of physical activity on cancer survival: a systematic review

PURPOSE

Physical activity (PA) has been suggested to help increase the survival of individuals with cancer. The objective of this review was to systematically evaluate and summarize the available evidence investigating the effect of PA on the survival of individuals with cancer.

METHODS

Electronic databases (CINAHL, EMBASE, and MEDLINE) were systematically searched for randomized controlled trials and cohort studies. Selected studies were assessed by two independent investigators for methodological quality, using the PEDro scale.

RESULTS

Ten prospective cohort studies met the inclusion criteria. Quality-assessment scores averaged 5/10 on the PEDro scale, with two articles obtaining a score of 6/10. The majority of studies found that individuals participating in higher levels of physical activity had a reduced risk of cancer-related mortality. This trend was observed specifically for breast, colon, and colorectal cancers. On average, it appears that engaging in higher levels of metabolic equivalent hours per week may help to improve survival rates among individuals diagnosed with cancer.

CONCLUSION

Patients diagnosed with cancer demonstrated a trend toward increased survival with greater levels of PA. However, because only prospective cohort studies were included in the study, the conclusions drawn should be regarded with caution.

Psychometric properties of the KPAS in diverse ethnic groups of midlife women

The Kaiser Physical Activity Survey (KPAS), designed specifically for diverse activity domains (housework, caregiving, occupational activity), is used to assess physical activity among multiethnic midlife women. This study evaluates KPAS reliability and validity (not widely documented) in measuring physical activity among 341 groups in this classification. Internal consistency coefficients are adequate for all ethnic groups except non-Hispanic (N-H) African Americans. To evaluate construct validity, the researchers use multiple analytic approaches, including correlation between behavioral intention and KPAS scores and factor analysis. KPAS scores correlate positively with behavioral intention scores among all ethnic groups. Eight factors are extracted among all groups except N-H Asian Americans. In the convergent validity test, N-H African Americans and N-H Asian Americans show unique patterns. Overall, the KPAS proves reliable as a reasonably accurate instrument to assess physical activities among multiethnic groups of midlife women. However, cultural sensitivity among N-H African Americans and N-H Asian Americans needs further examination.

Test-retest reliability of the Women's Health Initiative physical activity questionnaire

PURPOSE

Few physical activity (PA) questionnaires were designed to measure the lifestyles and activities of women. We sought to examine the test-retest reliability of a PA questionnaire used in the Women's Health Initiative (WHI) study. Differences in reliability were also explored by important covariates.

METHODS

Participants (n = 1092) were postmenopausal women aged 50-79 yr, randomly selected from the baseline sample of participants in the WHI Observational Study. The WHI PA questionnaire collects usual frequency, duration, and pace of recreational walking, frequency, and duration of other recreational activities or exercises (mild, moderate, and strenuous), household, and yard activities. Approximately half of the women (n = 569) repeated questions on recreational PA, the other half (n = 523) repeated questions related to household and yard activities (mean 3 months apart). Test-retest reliability was assessed with kappa and intraclass correlation coefficients (ICC 1,1).

RESULTS

Overall, questions on recreational walking, moderate recreational PA, and strenuous recreational PA had higher test-retest reliability (weighted kappa range = 0.50-0.60) than questions on mild recreational PA (weighted kappa range = 0.35-0.50). The ICC 1,1 for moderate to strenuous recreational PA was 0.77 (95% confidence interval [CI] = 0.73-0.80), and the total recreational PA was 0.76 (95% CI = 0.71-0.79). Substantial reliability was observed for the summary measures of yard activities (ICC 1,1 = 0.71; 95% CI = 0.66-0.75) and household activities (ICC 1,1 = 0.60, 95% CI = 0.55-0.66). No meaningful differences were observed by race/ethnicity, age, time between test and retest, and amount of reported PA.

CONCLUSIONS

The WHI PA questionnaire demonstrated moderate to substantial test-retest reliability in a diverse sample of postmenopausal women.

Physical activity assessment and health outcomes in old age: how valid are dose–response relationships in epidemiologic studies?

In this systematic review the validity of the dose–response relationships between physical activity (PA) and energy expenditure (EE) on defined health outcomes (cardio- and cerebrovascular morbidity and mortality, cancer) for the elderly is questioned. Medline, Cochrane, and EMBASE databases were reviewed for epidemiological longitudinal studies in populations aged 60+ for the years 1985–2007. Although most of the 18 identified studies generally demonstrated an inverse dose–response relationship between PA and EE level with morbidity and mortality, the range of dose–responses was remarkably broad. The nature of the dose–response relationship remained unclear. PA questionnaires - even those constructed for the elderly - do not cover the extremely diverse aspects of age-specific PA behavior and modes of muscular activity. Only non-age-specific tables had been used to estimate the EE in the elderly. Direct measurements of EE were limited. The results have implications for the interpretation of the dose–response relationships between PA and EE on defined health outcomes in old age.

Physical activity questionnaire comprehension: lessons from cognitive interviews

PURPOSE

To determine whether respondents share researchers' understandings of concepts and questions frequently used in the assessment of usual physical activity (PA) behavior.

METHODS

As part of On the Move, a study aimed at reducing measurement error in self-reported physical activity (PA), we conducted cognitive interviews with 19 men and 21 women, ages 45-65, regarding their responses to the PA questionnaires used in two large, population-based studies, Life After Cancer Epidemiology and California Men's Health study. One questionnaire asks about the frequency, the duration, and the perceived intensity of a range of specific activities in several different domains over the past 12 months. The second questionnaire asks about frequency and duration of specific, mostly recreational activities, grouped by intensity (i.e., moderate or vigorous) over the past 3 months. We used verbal probing techniques to allow respondents to describe their thought processes as they completed the questionnaires. All interviews were tape-recorded and transcribed, and the transcripts were then analyzed using standard qualitative methods.

RESULTS

Cognitive interviews demonstrated that a sizable number of respondents understood "intensity" in terms of emotional or psychological intensity rather than physical effort. As a result, the perceived intensity with which a participant reported doing a specific activity often bore little relationship to the MET value of that activity. Additionally, participants often counted the same activity more than once, overestimated work-related PA, and understood activities that were grouped together in a single category to be definitive lists rather than examples.

CONCLUSION

Cognitive interviews revealed significant gaps between respondents' interpretations of some PA questions and researchers' assumptions about what those questions were intended to measure. Some sources of measurement error in self-reported PA may be minimized by additional research that focuses on the cognitive processes required to respond to PA questionnaires.

Validation of the International Physical Activity Questionnaire-Short among Blacks

BACKGROUND

The International Physical Activity Questionnaire-Short Form (IPAQ-S) has been evaluated against accelerometer-determined physical activity measures in small homogenous samples of adults in the United States. There is limited information about the validity of the IPAQ-S in diverse US samples.

METHODS

142 Blacks residing in low-income housing completed the IPAQ-S and wore an accelerometer for up to 6 days. Both 1- and 10-minute accelerometer bouts were used to define time spent in light, moderate, and vigorous physical activity.

RESULTS

We found fair agreement between the IPAQ-S and accelerometer-determined physical activity (r=.26 for 10-minute bout, r=.36 for 1-minute bout). Correlations were higher among men than women. When we classified participants as meeting physical activity recommendations, agreement was low (kappa=.04, 10-minute; kappa=.21, 1-minute); only 25% of individuals were classified the same by both instruments (10-minute bout).

CONCLUSIONS

In one of the few studies to assess the validity of a self-reported physical activity measure among Blacks, we found moderate correlations with accelerometer data, though correlations were weaker for women. Correlations were smaller when IPAQ-S data were compared using a 10- versus a 1-minute bout definition. There was limited evidence for agreement between the instruments when classifying participants as meeting physical activity recommendations.

Lifestyle physical activity of older rural women

The purpose of this study was to describe and examine the lifestyle physical activity behaviors (household, leisure, occupational) of older rural women. Background characteristics included demographics, environment, social support, and health. Intrapersonal characteristics included motivation and self-efficacy. The majority of the women's energy expenditure was in the household dimension. Social support was positively associated with household activities. A higher level of leisure physical activity was associated with living within the two small cities and reporting lower levels of health and lower motivation. This research highlights the importance of household physical activity and the contribution of social support for household physical activity, both of which may be important in developing interventions to promote physical activity in older rural women.

Physical activity counseling in maternity and child health care - a controlled trial

BACKGROUND

The purpose of the study is to examine the effects and feasibility of individual physical activity (PA) counseling in maternity and child health clinics in Finland.

METHODS

Three clinics including both maternity and child health care signed up for the experimental (EXP) and three for the control group (CON). The participants were 132 pregnant and 92 postpartum primiparas. The nurses in EXP integrated a primary and four booster PA counseling sessions into routine visits. An option for supervised group exercise was offered. In CON former practices, usually including brief PA advice, were continued. Leisure-time PA (LTPA) prior to pregnancy was elicited by questionnaire and followed 16-18 and 36-37 weeks' gestation in maternity clinics and 5 and 10 months postpartum in child health clinics. Feasibility included safety, participant responsiveness, realization of counseling and applicability.

RESULTS

According to analysis of covariance adjusted for baseline LTPA and possible confounders, no relative between-group differences in LTPA were found at the first follow-up in either maternity or child health clinics. At the last follow-up in maternity clinics the weekly number of at least moderate-intensity LTPA days was 43% (95% CI: 9, 87) higher and the weekly duration of at least moderate-intensity LTPA 154% (95% CI: 16, 455) higher in EXP compared with CON. Counseling proved feasible in both maternity and child health clinics.

CONCLUSION

Counseling encouraged pregnant women to sustain their moderate-intensity LTPA and was feasible in routine practices. No effects were observed if counseling was initiated postpartum.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN21512277.

Using visual methods to uncover context

The accurate assessment of physical activity and dietary intake is essential for assessing the relationships between physical activity, dietary intake, and health outcomes. However, the measurement of physical activity and dietary intake among women, particularly minority women, poses unique challenges related to gender, ethnicity, and social context. Measures that are not culturally relevant or sensitive to the experiences, traditions, or beliefs of ethnically diverse women might result in data that are unreliable, or which cannot be interpreted. Visual methods show promise for elucidating concepts that are important to refine established measures for assessing dietary intake and physical activity in diverse ethnic groups. Hispanic women, a largely understudied subgroup that experiences long-term health risks associated with dietary and physical activity behaviors, serves as the focal group for this discussion of the potential for visual methods to develop culturally and contextually relevant and valid approaches to outcome assessment.

Factors that may mediate the relationship between physical activity and the risk for developing knee osteoarthritis

Studies investigating the effect of physical activity on risk for developing osteoarthritis at weight-bearing joints have reported conflicting results. We examine evidence to suggest that this may be due to the existence of subgroups of individuals who differ in their response to physical activity, as well as methodological issues associated with the assessment of knee joint structure and physical activity. Recommendations for future studies of physical activity and the development of knee osteoarthritis are discussed.

Safe to walk? Neighborhood safety and physical activity among public housing residents

BACKGROUND

Despite its health benefits, physical inactivity is pervasive, particularly among those living in lower-income urban communities. In such settings, neighborhood safety may impact willingness to be regularly physically active. We examined the association of perceived neighborhood safety with pedometer-determined physical activity and physical activity self-efficacy.

METHODS AND FINDINGS

Participants were 1,180 predominantly racial/ethnic minority adults recruited from 12 urban low-income housing complexes in metropolitan Boston. Participants completed a 5-d pedometer data-collection protocol and self-reported their perceptions of neighborhood safety and self-efficacy (i.e., confidence in the ability to be physically active). Gender-stratified bivariate and multivariable random effects models were estimated to account for within-site clustering. Most participants reported feeling safe during the day, while just over one-third (36%) felt safe at night. We found no association between daytime safety reports and physical activity among both men and women. There was also no association between night-time safety reports and physical activity among men (p = 0.23) but women who reported feeling unsafe (versus safe) at night showed significantly fewer steps per day (4,302 versus 5,178, p = 0.01). Perceiving one's neighborhood as unsafe during the day was associated with significantly lower odds of having high physical activity self-efficacy among both men (OR 0.40, p = 0.01) and women (OR 0.68, p = 0.02).

CONCLUSIONS

Residing in a neighborhood that is perceived to be unsafe at night is a barrier to regular physical activity among individuals, especially women, living in urban low-income housing. Feeling unsafe may also diminish confidence in the ability to be more physically active. Both of these factors may limit the effectiveness of physical activity promotion strategies delivered in similar settings.

The Reliability and Validity of the Physical Activity Survey in Long-Term Care

The purpose of this study was to develop and test a measure of physical activity for residents in long-term-care facilities, the Physical Activity Survey in Long-Term Care (PAS-LTC). Sixty-six activities are included in the PAS-LTC: routine physical activity, personal-care activities, structured exercise, recreational activities, caretaking activities, and repetitive activities. The study included 13 residents in a long-term-care facility, most of whom were women (62%), with an average age of 84 years (± 6.0) and an average Mini Mental State Examination score of 6 (± 6.9). There was evidence of interrater reliability of the PAS-LTC with intraclass correlations of .83-.94. There was some evidence of validity of the measure with statistically significant correlations between PAS-LTC recorded during the evening and night shifts and the number of counts of activity per the ActiGraph (r= .60 andr= .57, respectively,p< .05) and the calories estimated (r= .58 andr= .60, respectively,p< .05). The PAS-LTC completed during the day shift and total activity based on the PAS-LTC showed nonsignificant correlations of .40 or greater with the ActiGraph activity counts and calories.

The test-retest reliability of habitual incidental physical activity

OBJECTIVE

To determine the test-retest reliability of items measuring habitual incidental physical activity, incidental physical activity behaviour and sedentary behaviours.

METHODS

Eighty-four subjects aged 18-65 years were interviewed from randomly selected households within metropolitan and rural Western Australia. Subjects were administered the interview on two separate occasions 10 days apart. Subjects were asked about habitual incidental physical activity (i.e. bouts performed for 10 minutes or less) performed during the week and on weekends.

RESULTS

Intraclass correlations performed for items measuring incidental physical activity were generally found to be low to moderate. The frequency of incidental physical activity was more reliably recalled than the average duration spent on short trips (ICC 0.582 to 0.872 compared with 273 to 0.551). Kappa coefficients for habitual incidental physical activity behaviour items were observed to have moderate-to-high (0.478 to 0.939) agreement between administrations. Sedentary behaviours overall showed high test-retest reliability (ICC 0.646 to 0.925).

CONCLUSION

These findings demonstrate that adults can reliably recall the frequency, but not the duration, of habitual incidental physical activity. Thus, the frequency measured by these items could be used to determine the effectiveness of current Australian physical activity guidelines and possibly identify shifts in incidental physical activity behaviour over time.

IMPLICATIONS

Measurement of physical activity in all domains including incidental physical activity is required to determine the effectiveness of current guidelines and implemented health promotion interventions.

Effect of recreational physical activities on the development of knee osteoarthritis in older adults of different weights: the Framingham Study

OBJECTIVE

To evaluate the long-term effect of recreational exercise on the development of knee osteoarthritis (OA) in a community-based cohort of older adults, many of whom were overweight or obese.

METHODS

Subjects were asked about recreational activities including walking or jogging for exercise and working up a sweat, and were asked to compare their activity levels with others. Subjects were then asked about knee pain and weight-bearing anteroposterior and lateral knee radiographs were obtained. Approximately 9 years later, subjects were reexamined for OA. Radiographs were read for OA features in both tibiofemoral and patellofemoral compartments and were scored for tibiofemoral joint space narrowing. To evaluate incident OA, we excluded knees with OA at baseline for all analyses and focused on 3 knee-specific outcomes: incident radiographic OA, symptomatic OA, and tibiofemoral joint space loss. After adjusting for age, sex, body mass index (BMI), knee injury history, and correlation between knees, we evaluated the association of each recreational activity with OA development.

RESULTS

A total of 1,279 subjects underwent both baseline and followup examinations (mean age at baseline 53.2 years). Neither recreational walking, jogging, frequent working up a sweat, nor high activity levels relative to peers were associated with a decrease or increase in risk of OA. Joint space loss was also unaffected by activity. Persons with BMI above the median (27.7 kg/m(2) for men and 25.7 kg/m(2) for women; mean BMI >30 kg/m(2) for both) had no increases in risk of OA by different type of activity.

CONCLUSION

Among middle-aged and elderly persons without knee OA, many of whom were overweight, recreational exercise neither protects against nor increases risk of knee OA.

Does race/ethnicity moderate the association between job strain and leisure time physical activity?

BACKGROUND

Racial/ethnic minorities report myriad barriers to regular leisure time physical activity (LTPA), including the stress and fatigue resulting from their occupational activities.

PURPOSE

We sought to investigate whether an association exists between job strain and LTPA, and whether it is modified by race or ethnicity.

METHODS

Data were collected from 1,740 adults employed in 26 small manufacturing businesses in eastern Massachusetts. LTPA and job strain data were self-reported. Adjusted mean hours of LTPA per week are reported.

RESULTS

In age and gender adjusted analyses, reports of job strain were associated with LTPA. There was a significant interaction between job strain and race or ethnicity (p = .04). Whites experiencing job strain reported 1 less hr of LTPA per week compared to Whites not reporting job strain. Collectively, racial/ethnic minorities reporting job strain exhibited comparatively higher levels of LTPA compared to their counterparts with no job strain, although patterns for individual groups did not significantly differ.

CONCLUSIONS

Job strain was associated with LTPA in a lower income, multiethnic population of healthy adult men and women. The association between job strain and LTPA was modified by race or ethnicity, highlighting the importance of investigating the differential effects of psychosocial occupational factors on LTPA levels by race or ethnicity.

Evaluation of a short retrospective questionnaire for physical activity in women

Physical activity (PA) is discussed as a preventive factor for many chronic diseases. Thus, in epidemiological studies it often is an important covariate. Due to frequently long latency periods, long-term PA in the past is of greater interest than current PA. However, there is a lack of retrospective questionnaires that are validated for long-term PA, including occupational, household, and leisure activities. We therefore evaluated a short questionnaire for the comprehensive assessment of usual PA in distant age periods, administered with cognitive interviewing techniques. From an ongoing study on postmenopausal breast cancer 110 cases and 101 controls, age 50-74 years, were randomly selected. Our questionnaire was administered in a telephone interview more than two months after the main study interview, which included a detailed questionnaire on PA performed in the age periods 30-49 years and 50+ years. Total PA scores were derived from both interviews as MET-hours per week. Degree of agreement was assessed using Bland-Altman analyses. Further, potential sources of systematic and random error were investigated. The mean difference between both questionnaires was 3 MET hours/week, and 53.6% of absolute differences were below 35 MET hours/week, i.e. showing good agreement. Further 28.9% of differences could be considered acceptable agreement. Measurement errors seem to be non-differential with respect to cancer status. The median interviewing time was 10 min. Overall, this short questionnaire appears to be a useful and valid tool to distinguish between high and low levels of women's physical activity in the distant past.

Television viewing and pedometer-determined physical activity among multiethnic residents of low-income housing

OBJECTIVES

We evaluated the association between television viewing and pedometer-determined physical activity among predominantly racial/ethnic minority residents of low-income housing in metropolitan Boston in 2005.

METHODS

We used mixed models to analyze the association between reported hours of television viewing and pedometer-determined steps per day among 486 adults. We also examined whether television viewing was associated with the achievement of 10000 steps per day.

RESULTS

There was a mean 3.6 hours of average daily television watching. In multivariable analyses, each hour of television viewing on an average day was associated with 144 (95% confidence interval [CI]= -276, -12) fewer steps per day and a decreased likelihood of accumulating 10,000 steps per day (odds ratio [OR]=0.84; 95% CI=0.71, 0.99). Weekday and weekend television viewing were each also associated with fewer steps per day.

CONCLUSIONS

Average daily television viewing was associated with reductions in total pedometer-determined physical activity levels (approximately 520 steps per day) in this lower-income sample. As part of a comprehensive physical activity promotion plan, recommendations to reduce television viewing should be made.

Physical activity and Native Americans: a review

The physical activity behaviors of Native-American populations in the United States and Canada have received little attention in the health literature. The purpose of this review was to unite the literature regarding the physical activity behaviors of Native Americans. A majority of the literature was obtained using online databases. Reference lists were also reviewed to gain further access to the literature. Key-word searches included various combinations of Aboriginal, Native Indian, American Indian, Native American, First Nation, Métis, or Alaska Native with physical activity, exercise, and health behavior. Articles included were those published in English-language, peer-reviewed journals from 1990 until November 2005 that focused on participants aged 18 years and older. This review is organized according to ecologic models of health behavior, which take into account several correlates to explain human behavior, including demographic, personal health, environmental, and psychosocial. Correlates were included if they appeared at least three times in the literature. As a result of these inclusion criteria, the number of reviewed articles includes 28 quantitative, 4 qualitative, and 3 intervention studies. Results indicate that age, gender, and social support are important factors associated with physical activity. The remaining correlates show inconsistent or indeterminate results due in part to the paucity of research. It is suggested that an increase in the number of studies, especially those using longitudinal designs, is needed. Further, the application of psychosocial models to understand physical activity motivations as well as culturally appropriate and validated measurement tools are largely absent in the Native-American physical activity literature.

Pedometer-determined physical activity among multiethnic low-income housing residents

PURPOSE

We sought to characterize pedometer-determined physical activity among a predominantly racial and ethnic minority sample of adults residing in low-income housing.

METHODS

Data were collected from 433 participants at baseline in a randomized colon cancer prevention intervention trial conducted within low-income housing communities. Using random effects models to control for clustering within housing sites, we examined variation in daily steps by several sociodemographic characteristics.

RESULTS

Participants recorded a mean of 5326 (+/- 3871 SD) daily steps over a 5-d sampling period. Significantly lower levels of pedometer-determined physical activity were found among older-aged participants (P < 0.0001), women (P = 0.02), those who were overweight and obese (P = 0.03), those reporting no weekly exercise (P = 0.04), as well as among nonworking individuals (P < 0.0001). No significant differences were found by education or income. In multivariable analyses, age, gender, body mass index, and employment status remained significantly associated with steps.

CONCLUSIONS

These findings suggest a high prevalence of physical inactivity among low-income housing residents. These data, derived from a well-characterized sample, provide useful estimates for the investigation of pedometers as measures of total accumulated physical activity among lower-income, racial and ethnic minority populations.

Validation of the Kaiser Physical Activity Survey in pregnant women

PURPOSE

Participation in physical activity during pregnancy may reduce the risk of maternal and fetal disorders. However, few studies have validated physical activity questionnaires for use during pregnancy, a time characterized by different patterns of activity than nonpregnancy. Therefore, the aim of this study was to assess the validity and reliability of the Kaiser Physical Activity Survey (KPAS) for use during pregnancy.

METHODS

The KPAS, adapted from the Baecke physical activity survey, was designed specifically to assess physical activity in women. Unique features of the KPAS include the assessment of multiple domains of physical activity (household/caregiving, occupational, active living, and sports/exercise) as well as total activity. Summary KPAS indices were compared with objective (ActiGraph accelerometer by ActiGraph LLC) and subjective (Pregnancy Physical Activity Questionnaire (PPAQ)) measures of physical activity. Participants completed the self-administered PPAQ followed by the interviewer-administered KPAS and then wore the accelerometer for the following 7 d. At the end of the 7-d period, the questionnaires were repeated.

RESULTS

Intraclass correlation coefficients used to measure reproducibility of the KPAS were r = 0.84 for total activity and ranged from r = 0.76 for active living activities to r = 0.86 for occupational activity. Spearman correlations between the KPAS and three published cut points used to classify accelerometer data ranged from r = 0.49-0.59 for total activity, r = 0.12-0.26 for household/caregiving, r = 0.26-0.33 for occupational activity, r = 0.31-0.36 for active living, and r = 0.34-0.51 for sports/exercise. Spearman correlations between the KPAS and the PPAQ ranged from r = 0.71 for household/caregiving to r = 0.84 for sports/exercise.

CONCLUSIONS

The KPAS is a reliable and reasonably accurate instrument for estimating physical activity among pregnant women.

Development and validation of a Pregnancy Physical Activity Questionnaire

PURPOSE

The effect of physical activity during pregnancy on maternal and fetal health remains controversial and studies have yet to identify the optimal dose of physical activity associated with favorable pregnancy outcomes. The aim of this study was to develop and validate a pregnancy physical activity questionnaire (PPAQ).

METHODS

To ascertain the type, duration, and frequency of physical activities performed by pregnant women, three 24-h physical activity recalls were administered to 235 ethnically diverse prenatal care patients at a large tertiary care facility in western Massachusetts. The relative contribution of each activity to between-person variance in energy expenditure was used to establish the list of activities for the PPAQ. The PPAQ is self-administered and asks respondents to report the time spent participating in 32 activities including household/caregiving, occupational, sports/exercise, transportation, and inactivity. To validate the PPAQ, 54 pregnant women completed the PPAQ and then wore a Manufacturing Technology, Inc. actigraph for the following 7 d. At the end of the 7-d period, the PPAQ was repeated.

RESULTS

Intraclass correlation coefficients used to measure reproducibility of the PPAQ were 0.78 for total activity, 0.82 for moderate activity, 0.81 for vigorous activity, and ranged from 0.83 for sports/exercise to 0.93 for occupational activity. Spearman correlations between the PPAQ and three published cut points used to classify actigraph data ranged from 0.08 to 0.43 for total activity, 0.25 to 0.34 for vigorous activity, 0.20 to 0.49 for moderate activity, and -0.08 to 0.22 for light-intensity activity. Correlations were higher for sports/exercise and occupational activities as compared to household/caregiving activities.

CONCLUSIONS

household/caregiving activities.

CONCLUSIONS

The PPAQ is a reliable instrument of physical activities during pregnancy.

How Many Steps/Day Are Enough?

Pedometers are simple and inexpensive body-worn motion sensors that are readily being used by researchers and practitioners to assess and motivate physical activity behaviours. Pedometer-determined physical activity indices are needed to guide their efforts. Therefore, the purpose of this article is to review the rationale and evidence for general pedometer-based indices for research and practice purposes. Specifically, we evaluate popular recommendations for steps/day and attempt to translate existing physical activity guidelines into steps/day equivalents. Also, we appraise the fragmented evidence currently available from associations derived from cross-sectional studies and a limited number of interventions that have documented improvements (primarily in body composition and/or blood pressure) with increased steps/day.A value of 10000 steps/day is gaining popularity with the media and in practice and can be traced to Japanese walking clubs and a business slogan 30+ years ago. 10000 steps/day appears to be a reasonable estimate of daily activity for apparently healthy adults and studies are emerging documenting the health benefits of attaining similar levels. Preliminary evidence suggests that a goal of 10000 steps/day may not be sustainable for some groups, including older adults and those living with chronic diseases. Another concern about using 10000 steps/day as a universal step goal is that it is probably too low for children, an important target population in the war against obesity. Other approaches to pedometer-determined physical activity recommendations that are showing promise of health benefit and individual sustainability have been based on incremental improvements relative to baseline values. Based on currently available evidence, we propose the following preliminary indices be used to classify pedometer-determined physical activity in healthy adults: (i). <5000 steps/day may be used as a 'sedentary lifestyle index'; (ii). 5000-7499 steps/day is typical of daily activity excluding sports/exercise and might be considered 'low active'; (iii). 7500-9999 likely includes some volitional activities (and/or elevated occupational activity demands) and might be considered 'somewhat active'; and (iv). >or=10000 steps/day indicates the point that should be used to classify individuals as 'active'. Individuals who take >12500 steps/day are likely to be classified as 'highly active'.

In their own voices: definitions and interpretations of physical activity

Terms such as physical activity, exercise, and leisure are perceived and interpreted differently by people differing in gender, class, and sociocultural factors. We accessed multiple diverse data sources (including qualitative data recently collected in research and evaluation studies) to explore African-American and American Indian women's (age 40+) definitions, meanings, and interpretations of "physical activity". These women reported that physical activity is typically considered to be structured "exercise" and not incidental activities of daily life. The term "leisure" was interpreted from a cultural perspective as being lazy. These women also had difficulty understanding the meaning of "intensity" (e.g., "moderate", "vigorous"). Researchers must acknowledge and understand inconsistencies that arise and how these might influence design of, and responses to, self-report assessment of physical activity.

Limits to the measurement of habitual physical activity by questionnaires

Despite extensive use over 40 years, physical activity questionnaires still show limited reliability and validity. Measurements have value in indicating conditions where an increase in physical activity would be beneficial and in monitoring changes in population activity. However, attempts at detailed interpretation in terms of exercise dosage and the extent of resulting health benefits seem premature. Such usage may become possible through the development of standardised instruments that will record the low intensity activities typical of sedentary societies, and will ascribe consistent biological meaning to terms such as light, moderate, and heavy exercise.