Assessment of physical activity by accelerometer and IPAQ-short version in patients with chronic kidney disease undergoing hemodialysis

To compare the short version of International Physical Activity Questionnaire (IPAQ) and the accelerometer measurement of physical activity (PA) in patients undergoing hemodialysis. Sample consisted of 40 patients (19 men) aged 45 ± 16 years. Patients reported their PA using the IPAQ during a face-to-face interview, and wore an Actigraph GT3-X accelerometer for 1 week to obtain minutes per day of light PA, moderate-to-vigorous PA (MVPA) and total PA as well as raw counts per day (vector magnitude). All PA-related variables were significantly correlated among instruments (r = 0.34-0.47) when analyzed as a group. However, when analyzed separately by gender, the relationships were present for women only (r = 0.46-0.62). IPAQ significantly underestimated light PA (IPAQ vs. accelerometer: 180.0 vs. 251.1 min/day, p = 0.019), but no differences were found between methods for MVPA and total PA. Modest correlations were found between self-reported PA time by IPAQ (short version) and accelerometer, but only in women. However, the IPAQ may underestimate light PA, which is the main form of PA in this population.

Adiposity and age explain most of the association between physical activity and fitness in physically active men

[EN] BACKGROUND: To determine if there is an association between physical activity assessed by the short version of the International Physical Activity Questionnaire (IPAQ) and cardiorespiratory and muscular fitness. METHODOLOGY/PRINCIPAL FINDINGS: One hundred and eighty-two young males (age range: 20-55 years) completed the short form of the IPAQ to assess physical activity. Body composition (dual-energy X-Ray absorptiometry), muscular fitness (static and dynamic muscle force and power, vertical jump height, running speed [30 m sprint], anaerobic capacity [300 m running test]) and cardiorespiratory fitness (estimated VO(2)max: 20 m shuttle run test) were also determined in all subjects. Activity-related energy expenditure of moderate and vigorous intensity (EEPA(moderate) and EEPA(vigorous), respectively) was inversely associated with indices of adiposity (r = -0.21 to -0.37, P<0.05). Cardiorespiratory fitness (VO(2)max) was positively associated with LogEEPA(moderate) (r = 0.26, P<0.05) and LogEEPA(vigorous) (r = 0.27). However, no association between VO(2)max with LogEEPA(moderate), LogEPPA(vigorous) and LogEEPA(total) was observed after adjusting for the percentage of body fat. Multiple stepwise regression analysis to predict VO(2)max from LogEEPA(walking), LogEEPA(moderate), LogEEPA(vigorous), LogEEPA(total), age and percentage of body fat (%fat) showed that the %fat alone explained 62% of the variance in VO(2)max and that the age added another 10%, while the other variables did not add predictive value to the model [VO(2)max = 129.6-(25.1x Log %fat) - (34.0x Log age); SEE: 4.3 ml.kg(-1). min(-1); R(2) = 0.72 (P<0.05)]. No positive association between muscular fitness-related variables and physical activity was observed, even after adjusting for body fat or body fat and age. CONCLUSIONS/SIGNIFICANCE: Adiposity and age are the strongest predictors of VO(2)max in healthy men. The energy expended in moderate and vigorous physical activities is inversely associated with adiposity. Muscular fitness does not appear to be associated with physical activity as assessed by the IPAQ.

Regular physical activity moderates cardiometabolic risk in Alzheimer's caregivers

Dementia caregivers have an increased risk of cardiovascular disease, and it is possible that metabolic disturbances contribute to this risk. Regular physical exercise reduces cardiometabolic risk, but caregivers may have less opportunity to engage in such activity. We hypothesized that regular physical activity would moderate cardiometabolic risk in dementia caregivers.

Domains of physical activity and all-cause mortality: systematic review and dose-response meta-analysis of cohort studies

Background The dose–response relation between physical activity and all-cause mortality is not well defined at present. We conducted a systematic review and meta-analysis to determine the association with all-cause mortality of different domains of physical activity and of defined increases in physical activity and energy expenditure. Methods MEDLINE, Embase and the Cochrane Library were searched up to September 2010 for cohort studies examining all-cause mortality across different domains and levels of physical activity in adult general populations. We estimated combined risk ratios (RRs) associated with defined increments and recommended levels, using random-effects meta-analysis and dose–response meta-regression models. Results Data from 80 studies with 1 338 143 participants (118 121 deaths) were included. Combined RRs comparing highest with lowest activity levels were 0.65 [95% confidence interval (95% CI) 0.60–0.71] for total activity, 0.74 (95% CI 0.70–0.77) for leisure activity, 0.64 (95% CI 0.55–0.75) for activities of daily living and 0.83 (95% CI 0.71–0.97) for occupational activity. RRs per 1-h increment per week were 0.91 (95% CI 0.87–0.94) for vigorous exercise and 0.96 (95% CI 0.93–0.98) for moderate-intensity activities of daily living. RRs corresponding to 150 and 300 min/week of moderate to vigorous activity were 0.86 (95% CI 0.80–0.92) and 0.74 (95% CI 0.65–0.85), respectively. Mortality reductions were more pronounced in women. Conclusion Higher levels of total and domain-specific physical activity were associated with reduced all-cause mortality. Risk reduction per unit of time increase was largest for vigorous exercise. Moderate-intensity activities of daily living were to a lesser extent beneficial in reducing mortality.

Physical activity intensity and surrogate markers for cardiovascular health in adolescents

We examined the impact of physical activity (PA) on surrogate markers of cardiovascular health in adolescents. 52 healthy students (28 females, mean age 14.5 ± 0.7 years) were investigated. Microvascular endothelial function was assessed by peripheral arterial tonometry to determine reactive hyperemic index (RHI). Vagal activity was measured using 24 h analysis of heart rate variability [root mean square of successive normal-to-normal intervals (rMSSD)]. Exercise testing was performed to determine peak oxygen uptake ([Formula: see text]) and maximum power output. PA was assessed by accelerometry. Linear regression models were performed and adjusted for age, sex, skinfolds, and pubertal status. The cohort was dichotomized into two equally sized activity groups (low vs. high) based on the daily time spent in moderate-to-vigorous PA (MVPA, 3,000-5,200 counts(.)min(-1), model 1) and vigorous PA (VPA, >5,200 counts(.)min(-1), model 2). MVPA was an independent predictor for rMSSD (β = 0.448, P = 0.010), and VPA was associated with maximum power output (β = 0.248, P = 0.016). In model 1, the high MVPA group exhibited a higher vagal tone (rMSSD 49.2 ± 13.6 vs. 38.1 ± 11.7 ms, P = 0.006) and a lower systolic blood pressure (107.3 ± 9.9 vs. 112.9 ± 8.1 mmHg, P = 0.046). In model 2, the high VPA group had higher maximum power output values (3.9 ± 0.5 vs. 3.4 ± 0.5 W kg(-1), P = 0.012). In both models, no significant differences were observed for RHI and [Formula: see text]. In conclusion, in healthy adolescents, PA was associated with beneficial intensity-dependent effects on vagal tone, systolic blood pressure, and exercise capacity, but not on microvascular endothelial function.

Systematic counselling by general practitioners for promoting physical activity in elderly patients: a feasibility study

RESEARCH QUESTIONS: To investigate how the daily physical activities of elderly patients can be enhanced by systematic counselling conducted by general practitioners (GPs). METHODS: In this feasibility study with pre-post design, 29 people (14 females, mean age 72.2 years, SD = 6.1) were enrolled during routine visits by two general practitioners. A baseline assessment of current physical activity based on the stages according to the Transtheoretical Model was followed by a counselling session. The target behaviour was defined by performance of 30 minutes of daily moderate-intensity activities that increase the breathing rate, on five days per week. At the 2-month follow-up, subjects were assessed for improvement in stage of physical activity since baseline. After the end of the intervention, participating GPs and patients were asked questions focusing on the feasibility, acceptance and usefulness of counselling. RESULTS: Interview results showed that the two GPs considered the counselling protocol easy to handle and useful for promoting physical activity. Counselling sessions were especially encouraging for the not sufficiently active people. Most of them would like to have additional counselling session. At baseline, 9 of 29 people were sufficiently active. After 2 months, this proportion was 21 of 29. The mean of the number of minutes of physical activity during the previous 4 weeks increased from 247 to 436 minutes (weekly). CONCLUSIONS: The programme was judged positively by the general practitioners and the participating elderly patients. Systematic counselling by general practitioners led to an increase in the physical activity behaviour. Therefore, a more rigorous randomised controlled trial with adequate followup is recommended.

Ethnic Minority Children’s Active Commuting to School and Association with Physical Activity and Pedestrian Safety Behaviors

Background: Children's active commuting to school, i.e. walking or cycling to school, was associated with greater moderate-to-vigorous physical activity, although studies among ethnic minorities are sparse. Objectives: Among a low-income, ethnic minority sample of fourth grade students from eight public schools, we examined (1) correlates of active commuting to school and (2) the relationship between active commuting to school and moderate-to-vigorous physical activity. Methods: We conducted a cross-sectional analysis of baseline measurements from a sample of participants (n=149) aged 9-12 years from a walk to school intervention study in Houston, Texas. The primary outcome was the weekly rate of active commuting to school. Daily moderate-to-vigorous physical activity, measured by accelerometers, was a secondary outcome. Child self-efficacy (alpha=0.75), parent self-efficacy (alpha=0.88), and parent outcome expectations (alpha=0.78) were independent variables. Participant characteristics (age, gender, race/ethnicity, distance from home to school, acculturation, and BMI percentile) were independent sociodemographic variables. We used mixed-model regression analyses to account for clustering by school and a stepwise procedure with backward elimination of non-significant interactions and covariates to identify significant moderators and predictors. School-level observations of student pedestrians were assessed and compared using chi-square tests of independence. Results: Among our sample, which was 61.7% Latino, the overall rate of active commuting to school was 43%. In the mixed model for active commuting to school, parent self-efficacy (std. beta = 0.18, p=0.018) and age (std. beta = 0.18, p=0.018) were positively related. Latino students had lower rates of active commuting to school than non-Latinos ( 16.5%, p=0.040). Distance from home to school was inversely related to active commuting to school (std. beta = 0.29, p<0.001). In the mixed model for moderate-to-vigorous physical activity, active commuting to school was positively associated (std. beta = 0.31, p <0.001). Among the Latino subsample, child acculturation was negatively associated with active commuting to school (std. beta = -0.23, p=0.01). With regard to school-level pedestrian safety observations, 37% of students stopped at the curb and 2.6% looked left-right-left before crossing the street. Conclusion: Although still below national goals, the rate of active commuting was relatively high, while the rate of some pedestrian safety behaviors was low among this low-income, ethnic minority population. Programs and policies to encourage safe active commuting to school are warranted and should consider the influence of parents, acculturation, and ethnicity.

Physical Activity and Risk of Bleeding in Elderly Patients Taking Anticoagulants.

BACKGROUND Although the possibility of bleeding during anticoagulant treatment may limit patients from taking part in physical activity, the association between physical activity and anticoagulation-related bleeding is uncertain. OBJECTIVES To determine whether physical activity is associated with bleeding in elderly patients taking anticoagulants. PATIENTS/METHODS In a prospective multicenter cohort study of 988 patients aged ≥65 years receiving anticoagulants for venous thromboembolism, we assessed patients' self-reported physical activity level. The primary outcome was the time to a first major bleeding, defined as fatal bleeding, symptomatic bleeding in a critical site, or bleeding causing a fall in hemoglobin or leading to transfusions. The secondary outcome was the time to a first clinically-relevant non-major bleeding. We examined the association between physical activity level and time to a first bleeding using competing risk regression, accounting for death as a competing event. We adjusted for known bleeding risk factors and anticoagulation as a time-varying covariate. RESULTS During a mean follow-up of 22 months, patients with a low, moderate, and high physical activity level had an incidence of major bleeding of 11.6, 6.3, and 3.1 events per 100 patient-years, and an incidence of clinically relevant non-major bleeding of 14.0, 10.3, and 7.7 events per 100 patient-years, respectively. A high physical activity level was significantly associated with a lower risk of major bleeding (adjusted sub-hazard ratio 0.40, 95%-CI 0.22-0.72). There was no association between physical activity and non-major bleeding. CONCLUSIONS A high level of physical activity is associated with a decreased risk of major bleeding in elderly patients receiving anticoagulant therapy. This article is protected by copyright. All rights reserved.

Physical activity interventions in schools for improving lifestyle in European countries

Background: In the last decades, children’s and adolescents’ obesity and overweight have increased in European Countries. Unhealthy eating habits and sedentary lifestyle have been recognized to determine such an epidemic. Schools represent an ideal setting to modify harmful behaviors, and physical activity could be regarded as a potential way to avoid the metabolic risks related to obesity. Methods: A systematic review of the literature was carried out to summarize the evidence of school-based interventions aimed to promote, enhance and implement physical activity in European schools. Only randomized controlled trials were included, carried out in Europe from January 2000 to April 2014, universally delivered and targeting pupils aged between 3 and 18 years old. Results: Forty-seven studies were retrieved based either on multicomponent interventions or solely physical activity programs. Most aimed to prevent obesity and cardiovascular risks among youths. While few studies showed a decrease in BMI, positive results were achieved on other outcomes, such as metabolic parameters and physical fitness. Conclusion: Physical activity in schools should be regarded as a simple, non-expensive and enjoyable way to reach all the children and adolescents with adequate doses of moderate to vigorous physical activity.

Life style habits such as alcohol consumption and physical activity in relation to serum apoB / apoA-I ratio amongst 64-year-old women with varying degrees of glucose tolerance.

OBJECTIVES To investigate how life style factors such as alcohol consumption and physical activity relate to the serum apoB / apoA-I ratio in a cohort of middle-aged women with varying degrees of glucose tolerance. DESIGN Observational, cross-sectional cohort study. SETTING Research laboratory at a University Hospital. SUBJECTS A screened cohort of 64-year-old postmenopausal women with varying degrees of glucose tolerance, ranging from diabetes (n = 232), impaired (n = 212) and normal (n = 191) glucose tolerance. MAIN OUTCOME MEASURE ApoB / apoA-I ratio in relation to alcohol consumption and physical activity as assessed by questionnaires. RESULTS Alcohol consumption and regular physical activity at high levels were inversely associated with the serum apoB / apoA-I ratio independently of confounding factors such as obesity, lipid-lowering treatment, degree of glucose tolerance and hormone replacement therapy. Alcohol seemed related to the apoB / apoA-I ratio mainly through increasing apoA-I, whereas physical activity seemed mainly related to lowering of apoB. Alcohol consumption above a daily intake of 8.9 g, i.e. less than a glass of wine was accompanied by a decrease in apoB / apoA-I ratio. CONCLUSIONS Amongst these 64-year-old women with varying degrees of glucose tolerance, a moderate alcohol intake and regular physical exercise leading to sweating were associated with lower apoB / apoA-I ratio and these effects seem to be additive.

Physical activity and liver diseases

Regular physical activity beneficially impacts the risk of onset and progression of several chronic diseases. However, research regarding the effects of exercising on chronic liver diseases is relatively recent. Most authors focused on non-alcoholic fatty liver disease (NAFLD), in which increasing clinical and experimental data indicate that skeletal muscle cross-talking to the adipose tissue and the liver regulates intrahepatic fat storage. In this setting physical activity is considered required in combination with calories restriction to allow an effective decrease of intrahepatic lipid component, and despite that evidence is not conclusive, some studies suggest that vigorous activity might be more beneficial than moderate activity to improve NAFLD/NASH. Evidence regarding the effects of exercise on the risk of hepatocellular carcinoma is scarce; some epidemiological studies indicate a lower risk in patients regularly and vigorously exercising. In compensated cirrhosis exercise acutely increases portal pressure, but in longer term it has been proved safe and probably beneficial. Decreased aerobic capacity (VO2) correlates with mortality in patients with decompensated cirrhosis, who are almost invariably sarcopenic. In these patients VO2 is improved by physical activity, which might also reduce the risk of hepatic encephalopathy through an increase in skeletal muscle mass. In solid organ transplantation recipients exercise is able to improve lean mass, muscle strength and as a consequence, aerobic capacity. Few data exist in liver transplant recipients, in whom exercise should be object of future studies given its high potential of providing long-term beneficial effects. Despite evidence is far from complete, physical activity should be seen as an important part of the management of patients with liver disease in order to improve their clinical outcome. This article is protected by copyright. All rights reserved.

Adherence to a lifestyle physical activity program: Trends over time and associations with processes of change and physical activity

Research on lifestyle physical activity interventions suggests that they help individuals meet the new recommendations for physical activity made by the Centers for Disease Control and Prevention (CDC) and the American College of Sports Medicine (ACSM). The purpose of this research was to describe the rates of adherence to two lifestyle physical activity intervention arms and to examine the association between adherence and outcome variables, using data from Project PRIME, a lifestyle physical activity intervention based on the transtheoretical model and conducted by the Cooper Institute of Aerobics Research, Dallas, Texas. Participants were 250 sedentary healthy adults, aged 35 to 70 years, primarily non-Hispanic White, and in the contemplation and preparation stages of readiness to change. They were randomized to a group (PRIME G) or a mail- and telephone-delivered condition (PRIME C). Adherence measures included attending class (PRIME G), completing a monthly telephone call with a health educator (PRIME C), and completing homework assignments and self-monitoring minutes of moderate- to vigorous physical activity (both groups). In the first results paper, adherence over time and between conditions was examined: Attendance in group, completing the monthly telephone call, and homework completion decreased over time, and participants in PRIME G were more likely to complete homework than those in PRIME C. Paper 2 aimed to determine whether the adherence measures predicted achievement of the CDC/ACSM physical activity guideline. In separate models for the two conditions, a latent variable measuring adherence was found to predict achievement of the guideline. Paper 3 examined the association between adherence measures and the transtheoretical model's processes of change within each condition. For both, participants who completed at least two thirds of the homework assignments improved their use of the processes of change more than those who completed less than that amount. These results suggest that encouraging adherence to a lifestyle physical activity intervention, at least among already motivated volunteers, may increase the likelihood of beneficial changes in the outcomes. ^

Community referral for promoting physical activity among primary care patients

Introduction. There is a need for physical activity interventions based in primary care clinics that take advantage of community resources. The purpose of this randomized controlled trial was to compare the effects of two physical activity interventions: (1) physical activity prescription by a primary care provider plus referral to community physical activity resources and (2) physical activity prescription only. ^ Methods. Sedentary adult patients recruited from a general medicine clinic were randomized to receive a physical activity prescription, delivered by the primary care provider, plus referral to community physical activity resources (n=38) or physical activity prescription only (n=32). Outcomes were use of community resources (exercise facility and personal trainers), physical activity levels (self-report questionnaire and pedometer), and attitudes regarding physical activity assessed at 8 weeks. ^ Results. Three of 38 (7.9%) subjects referred to the community resources and none of the 32 subjects in the prescription only group used the community resources during the 8 week trial. Sixteen of 32 subjects in the prescription plus referral group and 19 of 38 in the prescription group completed the self-report follow-up forms at 8 weeks. For minutes of moderate- or vigorous-intensity physical activity per week, there were no between-group differences at baseline, follow-up, or change from baseline to follow-up. However, for moderate- and vigorous-intensity physical activity, there were significant improvements from baseline to follow-up within each group. For attitudes related to physical activity, there were no between-group differences at baseline, follow-up, or change from baseline to follow-up; neither were there any within-group changes. ^ Discussion. Physical activity prescription delivered by a healthcare provider in the context of a routine primary care visit can improve physical activity levels, with no additional improvement gained by referring to community resources. The intervention was feasible for primary care providers to deliver, but only 50% of subjects returned the self-report physical activity questionnaire at the 8 week assessment. ^

The association between classroom characteristics and student physical activity in physical education classrooms

Background. With the rapid rise in childhood obesity, physical activity participation among young children has become the subject of much recent attention. Physical education classes have been specifically targeted as a method of providing opportunities for all children to be active. Unfortunately, student participation in moderate-to-vigorous physical activity during these classes still falls far below the current recommendations. While some research to date has reported the levels of activity among elementary-aged children, research is limited on the relationship between these activity levels and the environmental characteristics that exist within the PE classroom. ^ Purpose. The purpose of this study is to examine the association between specific classroom characteristics and contextual characteristics (lesson context, class size, class location, teacher gender, and teacher encouragement for PA) with elementary aged children's moderate-to-vigorous activity during PE class. ^ Methods. A secondary analysis of 211 3rd, 4th and 5th grade physical education classes amongst 39 elementary schools in Harris County, TX and 35 elementary schools in Travis County, TX was conducted using cross-sectional data from the evaluation of a school-based health program. Lesson context and student activity levels were measured using a direct observation measurement tool. Additionally, these variables were further analyzed against a number of classroom characteristics to determine any significant associations. ^ Results. Overall, elementary PE classes are still participating in low levels of moderate-to-vigorous physical activity averaging only 38% of class time. Additionally, close to 25% of class time is spent in classroom management. Male directed classes spent significantly more time in game activities and female directed classes spent more time in fitness, knowledge, and skill activities. Classes that took place outdoors were more active and spent more time in games than those that took place indoors. Significant correlations were demonstrated between class size and time spent in management context. Time spent in management context was also correlated with time spent sitting and standing. Additionally, positive correlations were demonstrated between time very active and teachers that praised students and encouraged physical activity among their classes.^

Validity and reliability of using MVP 4 Function Walk4Life digital pedometers to assess physical activity levels among preschool-aged Head Start children

The Surgeon General recommends preschoolers 3-5 years old accumulate 60 minutes of moderate-to-vigorous physical activity (MVPA) per day. However, there is limited data measuring physical activity (PA) and MVPA amongst this population. The purpose of this cross-sectional study is to determine the validity, reliability, and feasibility of using MVP 4 Function Walk4Life digital pedometers (MVP-4) in measuring MVPA among preschoolers using the newly modified direct observational technique, System for Observing Fitness Instruction Time-Preschool Version (SOFIT-P) as the gold standard. An ethnically diverse population of 3-5 year old underserved children were recruited from two Harris County Department of Education (HCDE) Head Start centers. For 2 days at baseline and 2 days at post-test, 75 children enrolled wore MVP-4 pedometers for approximately 6-hours per observation day and were observed using SOFIT-P during predominantly active times. Statistical analyses used Pearson "r" correlation coefficients to determine mean minutes of PA and MVPA, convergent and criterion validity, and reliability. Significance was set at p = <0.05. Feasibility was determined through process evaluation information collected during this study via observations from data collectors and teacher input. Results show mean minutes of PA and MVPA ranged between 30-42 and 11-14 minutes, respectively. Convergent validity comparing BMI percentiles with MVP-4 PA outcomes show no significance at pre-test; however, each measurement at post-test showed significance for MVPA (p = 0.0247, p = 0.0056), respectively. Criterion validity comparing percent MVPA time between SOFIT-P and MVP-4 pedometers was determined; however, results deemed insufficient due to inconsistency in observation times while using the newly developed SOFIT-P. Reliability measures show no significance at pre-test, yet show significant results for all PA outcomes at post-test (p = 0.001, p = 0.001, p = 0.0010, p = 0.003), respectively. Finally, MVP-4 pedometers lacked feasibility due to logistical barriers in design. Researchers feel the significant results at post-test are secondary to increased familiarity and more accurate placement of pedometers across time. Researchers suggest manufacturers of MVP-4 pedometers further modify the instrument for ease of use with this population, following which future studies ought to determine validity using objective measures or all-day direct observation techniques.^