Different Methods Yielded Two-Fold Difference in Compliance with Physical Activity Guidelines on School Days

Introduction

The aim was to compare the average and the days method in exploring the compliance of children with physical activity guidelines and describe their physical activity patterns in different school day segments.

Methods

Physical activity was objectively measured in 472 children aged 6–13 for one school week. Children were compliant when fulfilling PA recommendations 1) on average over all measured days (average method) or 2) on at least four measured days (days method). To explore the difference in moderate to vigorous physical activity (MVPA) minutes between compliant and non-complaint children (using both the average and days method) in various day segments, linear mixed models was used.

Results

Compliance with physical activity guidelines was significantly higher with the average compared to the days method (51.7% and 23.7%, respectively). In segmented-day analysis, compliant children accrued more MVPA minutes in all day segments, especially during after-school. Gender differences appeared only during the in-school segments, where girls spent less time in MVPA (average method: -4.39 min, 95% CI = -5.36,-3.42, days method: -4.45 min, 95%CI = -5.46,-3.44). Older children accrued more MVPA minutes during physical education classes, but less during breaks, compared to younger children.

Conclusions

The used methods yielded remarkably different prevalence estimates for compliance to physical activity recommendations. To ensure comparability between studies, interventions and reports, there is a need for internationally agreed operationalization and assessment methods of physical activity guidelines. As non-compliant children had lower MVPA during all day segments, greater efforts should be made to provide physical activity opportunities both during and after school.     

Associations of Objectively Assessed Physical Activity and Sedentary Time with All-Cause Mortality in US Adults: The NHANES Study

Background

Sedentary behavior is related to increased mortality risk. Whether such elevated risk can be offset by enhanced physical activity has not been examined using accelerometry data.

Materials and Methods

We examined the relations of sedentary time and physical activity to mortality from any cause using accelerometry data among 1,677 women and men aged 50 years or older from the National Health and Nutrition Examination Survey (NHANES) 2003–2004 cycle with follow-up through December 31, 2006.

Results

During an average follow-up of 34.67 months and 4,845.42 person-years, 112 deaths occurred. In multivariate Cox proportional hazard models, greater sedentary time (≥ median of 8.60 hours/day) was associated with increased risk of mortality from any cause (relative risk (RR) = 2.03; 95% confidence interval (CI) = 1.09-3.81). Low level of moderate to vigorous physical activity (< median of 6.60 minutes/day) was also related to enhanced all-cause mortality risk (RR = 3.30; 95% CI = 1.33-8.17). In combined analyses, greater time spent sedentary and low levels of moderate to vigorous physical activity predicted a substantially elevated all-cause mortality risk. As compared with the combination of a low sedentary level and a high level of moderate to vigorous physical activity, the risks of mortality from all causes were 4.38 (95% CI = 1.26-15.16) for low levels of both sedentary time and physical activity, 2.79 (95% CI = 0.77-10.12) for greater time spent sedentary and high physical activity level, and 7.79 (95% CI = 2.26-26.82) for greater time spent sedentary and low physical activity level. The interaction term between sedentary time and moderate to vigorous physical activity was not statistically significant (p = 0.508).

Conclusions

Both high levels of sedentary time and low levels of moderate to vigorous physical activity are strong and independent predictors of early death from any cause. Whether a high physical activity level removes the increased risk of all-cause mortality related to sedentariness requires further investigation.     

Physical Activity Levels and Domains Assessed by Accelerometry in German Adolescents from GINIplus and LISAplus

Background

Physical activity (PA) is a well-known and underused protective factor for numerous health outcomes, and interventions are hampered by lack of objective data. We combined accelerometers with diaries to estimate the contributions to total activity from different domains throughout the day and week in adolescents.

Methods

Accelerometric and diary data from 1403 adolescents (45% male, mean age 15.6 ± 0.5 years) were combined to evaluate daily levels and domains of sedentary, light, and moderate-to-vigorous activity (MVPA) during a typical week. Freedson’s cutoff points were applied to determine levels of activity. Total activity was broken down into school physical education (PE), school outside PE, transportation to school, sport, and other time.

Results

About 2/3 of adolescents’ time was spent sedentary, 1/3 in light activity, and about 5% in MVPA. Boys and girls averaged 46 (SD 22) and 38 (23) minutes MVPA per day. Adolescents were most active during leisure sport, spending about 30% of it in MVPA, followed by PE (about 20%) transport to school (14%) and either school class time or other time (3%). PE provided 5% of total MVPA, while leisure sport provided 16% and transportation to school 8%. School was the most sedentary part of the day with over 75% of time outside PE spent sedentary.

Conclusions

These German adolescents were typical of Europeans in showing low levels of physical activity, with significant contributions from leisure sport, transportation and school PE. Leisure sport was the most active part of the day, and participation did not vary significantly by sex, study center (region of Germany) or BMI. Transportation to school was frequent and thus accounted for a significant fraction of total MVPA. This indicates that even in a population with good access to dedicated sporting activities, frequent active transportation can add significantly to total MVPA.     

The Associations of Objectively Measured Physical Activity and Sedentary Time with Cognitive Functions in School-Aged Children

Low levels of physical activity among children have raised concerns over the effects of a physically inactive lifestyle, not only on physical health but also on cognitive prerequisites of learning. This study examined how objectively measured and self-reported physical activity and sedentary behavior are associated with cognitive functions in school-aged children. The study population consisted of 224 children from five schools in the Jyväskylä school district in Finland (mean age 12.2 years; 56% girls), who participated in the study in the spring of 2011. Physical activity and sedentary time were measured objectively for seven consecutive days using the ActiGraph GT1M/GT3X accelerometer. Self-reported moderate to vigorous physical activity (MVPA) and screen time were evaluated with the questions used in the “WHO Health Behavior in School-aged Children” study. Cognitive functions including visual memory, executive functions and attention were evaluated with a computerized Cambridge Neuropsychological Test Automated Battery by using five different tests. Structural equation modeling was applied to examine how objectively measured and self-reported MVPA and sedentary behavior were associated with cognitive functions. High levels of objectively measured MVPA were associated with good performance in the reaction time test. High levels of objectively measured sedentary time were associated with good performance in the sustained attention test. Objectively measured MVPA and sedentary time were not associated with other measures of cognitive functions. High amount of self-reported computer/video game play was associated with weaker performance in working memory test, whereas high amount of computer use was associated with weaker performance in test measuring shifting and flexibility of attention. Self-reported physical activity and total screen time were not associated with any measures of cognitive functions. The results of the present study propose that physical activity may benefit attentional processes. However, excessive video game play and computer use may have unfavorable influence on cognitive functions.     

Moving through Life-Space Areas and Objectively Measured Physical Activity of Older People

Objectives

Physical activity–an important determinant of health and function in old age–may vary according to the life-space area reached. Our aim was to study how moving through greater life-space areas is associated with greater physical activity of community-dwelling older people. The association between objectively measured physical activity and life-space area reached on different days by the same individual was studied using one-week longitudinal data, to provide insight in causal relationships.

Methods

One-week surveillance of objectively assessed physical activity of community-dwelling 70–90-year-old people in central Finland from the “Life-space mobility in old age” cohort substudy (N = 174). In spring 2012, participants wore an accelerometer for 7 days and completed a daily diary including the largest life-space area reached (inside home, outside home, neighborhood, town, and beyond town). The daily step count, and the time in moderate (incl. walking) and low activity and sedentary behavior were assessed. Differences in physical activity between days on which different life-space areas were reached were tested using Generalized Estimation Equation models (within-group comparison).

Results

Participants’ mean age was 80.4±4.2 years and 63.5% were female. Participants had higher average step counts (p < .001) and greater moderate and low activity time (p < .001) on days when greater life-space areas were reached, from the home to the town area. Only low activity time continued to increase when moving beyond the town.

Conclusion

Community-dwelling older people were more physically active on days when they moved through greater life-space areas. While it is unknown whether physical activity was a motivator to leave the home, intervention studies are needed to determine whether facilitation of daily outdoor mobility, regardless of the purpose, may be beneficial in terms of promoting physical activity.     

Association between Physical Activity Knowledge and Levels of Physical Activity in Chinese Adults with Type 2 Diabetes

BackgroundPhysical activity (PA) is an important treatment regimen for diabetes. The purposes of this study were to evaluate people’s knowledge of how exercise influences wellbeing (termed “PA knowledge” or “knowledge of PA” in this paper) and the resulting association with levels of PA in Chinese adults with Type 2 diabetes, and to identify the valuable demographic and lifestyle factors that possibly influence the association between PA knowledge and level of PA.MethodsTwo hundred and fifty-eight adults with Type 2 diabetes completed an interviewer-administered survey at a diabetes clinic in Hong Kong. Data on demographics, lifestyle factors and diabetes-related medical indicators were obtained. A 20-item questionnaire was developed to measure PA-related knowledge (one point scored for each correct answer; aggregate score up to 20 points). level of PA was measured by the International Physical Activity Questionnaire.ResultsThe proportions of correct answers to each question ranged from 19.4 to 90.7%. Compared with poorly educated participants, those with university education level and above had PA knowledge scores 1.7 points higher (14.3 vs. 12.6, P<0.05). Younger, female, and obese participants were more likely to have lower level of PA (all P<0.05). After adjustment for age, gender, (BMI) and education level, the odds of having a moderate-to-high level of PA was 19% greater with 1 unit increase in PA knowledge score [95% confidence interval (CI): 1.09–1.29; P<0.001], this association was strongest in participants with tertiary education level or above [odds ratio (OR): 1.35; 95% CI: 1.03–1.77; P<0.05].ConclusionsPA knowledge was positively associated with level of PA. Education level significantly influenced the association between PA knowledge and level of PA, leading to the suggestion of vulnerable groups to target for PA improvement in the face of diabetes.     

Objectively Measured Intensity of Physical Activity and Adiposity in Middle‐Aged Women

Objective: The aim of this study was to evaluate the relationship between objectively measured physical activity (ACT), particularly intensity of physical activity (iACT), and body fat percentage (BF%) in 278 middle‐aged women. Secondary purposes were to ascertain the association between physical activity duration (dACT) and BF% and the extent to which potentially confounding factors, including total ACT, energy intake, body weight, and season of assessment, influenced the relationship between iACT and BF%. Research Methods and Procedures: A cross‐sectional design was used. Subjects were apparently healthy, 35 to 45 years old, premenopausal, nonsmokers, with BMIs < 30 kg/m². Approximately 90 percent were white, 81% were married, and 37% were college graduates. ACT was assessed using Computer Science and Application accelerometers worn for 7 consecutive days. The accelerometers recorded movement continuously, and activity counts were collapsed into 10‐minute epochs. Intensity was indexed using seven activity count cut‐off points, and duration was based on the number of 10‐minute epochs at each intensity level. BF% was assessed using multiple measurements in the Bod Pod. Energy intake was measured using 7‐day weighed diet records during the same week subjects wore the accelerometers. Results: BF% was strongly and inversely associated with iACT and dACT. Controlling for energy intake and body weight strengthened the relationships among iACT, dACT, and BF%. Control of total ACT weakened the association. Discussion: Engaging in higher intensity and/or longer duration ACT is associated with lower BF% compared with lower intensity and/or shorter durations of activity.     

Variability in Physical Activity Assessed with Accelerometer Is an Independent Predictor of Mortality in CHF Patients

AimsPatients with heart failure often display a distinct pattern of walking characterized by short step-length and frequent short pauses. In the current study we sought to explore if qualitative aspects of movement have any additive value to established factors to predict all-cause mortality in patients with advanced heart failure.ConclusionThe feature skewness, a measure of asymmetry in the intensity level of periods of high physical activity, was identified to be predictive of all-cause mortality independent of the established prognostic model–HFSS and peak VO2. The findings from the present study emphasize the use of accelerometer analysis in clinical practice to make more accurate prognoses in addition to extract features of physical activity relevant to functional classification.     

Health Perceptions,Self and Body Image,Physical Activity and Nutrition among Undergraduate Students in Israel

Purpose

This study examines health perceptions, self and body image, physical exercise and nutrition among undergraduate students.

Methods

A structured, self-reported questionnaire was administered to more than 1500 students at a large academic institute in Israel. The study population was heterogenic in both gender and fields of academic study.

Results

High correlations between health perceptions, appropriate nutrition, and positive self and body image were found. The relationships between these variables differed between the subpopulation in the sample and the different genders. Engagement in physical exercise contributed to positive body image and positive health perceptions more than engagement in healthy nutrition. Nutrition students reported higher frequencies of positive health perceptions, positive self and body image and higher engagement in physical exercise in comparison to all other students in the sample.

Conclusions

This study suggests, as have many before, that successful health promotion policy should reflect a collectivist rather than an individualist ethos by providing health prerequisites through a public policy of health-promotion, where the academic settings support a healthy lifestyle policy, by increasing availability of a healthy, nutritious and varied menu in the cafeterias, and offering students various activities that enhance healthy eating and exercise.

Implications and contribution

This study examined health perceptions, self-image, physical exercise and nutrition among undergraduate students and found high correlations between these topics. Nutrition students reported higher frequencies of positive health perceptions, and positive self and body image and engaged more in physical exercise when compared with all other students in the sample.     

Serum Interleukin-18 Levels Are Associated with Physical Activity in Japanese Men

Objective

To investigate the link between serum interleukin-18 (IL-18) levels and physical activity in Japanese men.

Methods

A total of 81 men (45.7±17.6 years old) was enrolled in this cross-sectional investigation study. We assessed anthropometric and body composition parameters. Serum IL-18 levels, physical activity by uniaxial accelerometers, peak oxygen uptake and metabolic risk parameters were also evaluated.

Results

Serum IL-18 levels were 179.4±84.7 pg/mL. Physical activity evaluated by Σ[metabolic equivalents × h per week (METs⋅h/w)]was significantly and negatively correlated with serum IL-18 levels (r = −0.252, p = 0.0235). These associations remained even after adjusting for age, peak oxygen uptake and other confounding factors.

Conclusion

Serum IL-18 levels were closely associated with physical activity independent of peak oxygen uptake in Japanese men.     

NOR Activity in Wheat Species with Different Ploidy Levels Treated with Phytohormones

The effects of the phytohormones 6-benzylaminopurine (BAP) and 24-epibrassinolide (EB) on the sizes of nucleoli in the interphase nuclei of root meristem were studied using the silver-staining procedure in wheat species with different ploidy levels (a polyploid series). In addition, the effects of the phytohormones on the cell mitotic activity in the roots of 5-day-old seedlings were studied. The higher the wheat species ploidy level, the higher its sensitivities to BAP and EB were. In diploid wheat, the maximum increase in the nucleolar organizing region (NOR) activity was observed after treatment with considerably higher phytohormone concentrations compared to tetra- and hexaploid wheat species. The phytohormone treatment increased both the sizes and the number of nucleoli in meristematic cells of seedling roots in all wheat species studied. It was assumed that the differences between the responses of wheat species with three different ploidy levels to different concentrations of phytohormones were related to their effects on the methylation/demethylation of cytosine residues in the rDNA promoter region.     

Patterns and Associated Factors of Physical Activity among Adolescents in Nigeria

Introduction

Understanding the context where adolescents’ physical activity (PA) takes place could impact a more targeted approach to implement PA promotion and interventions in Africa. However, standardized data on adolescents’ PA behaviour is lacking in Nigeria. We described PA patterns in the various domains (home, school, transport, leisure-time) and intensity categories (light-intensity PA, moderate- to vigorous- intensity physical activity [MVPA] and total PA), and their associations with sociodemographic factors and socioeconomic status (SES) among secondary school adolescents in Nigeria.

Methods

A cross-sectional survey was conducted in a representative sample of 1006 secondary school adolescents (12–18 years, 50.4% girls) in Maiduguri, Nigeria. Self-reported PA was assessed with an adapted version of the Activity Questionnaire for Adolescents and Young Adults. Outcomes were weekly minutes (min/wk) of PA spent in the various domains and intensity categories. Multivariate ANOVA was used to examine associations of PA scores (domains and intensity levels) with adolescents’ sociodemographic characteristics and SES, and track differences in PA scores between subgroups.

Results

The total sample reported most PA at school (1525 min/wk), the least during active transportation (210 min/wk), and only 37% engaged in 60 min of MVPA daily. Boys reported significantly more leisure-time PA (P<0.001), active transportation (P<0.001), MVPA (P = 0.023) and total PA (P = 0.003) than girls, while girls reported more school-based PA (P = 0.009), home-based PA (P<0.001) and light-intensity PA (P<0.001) than boys. Moderate-intensity PA (P = 0.024) and total PA (P = 0.049) were significantly higher in younger age group than in older group. Household car ownership was associated with less active transportation (P = 0.009), less moderate-intensity PA (P = 0.048) and with more leisure-time PA (P = 0.013). High parental SES was associated with more leisure-time PA (P = 0.002), more MVPA (P = 0.047) and less active transportation (P<0.001). Adolescents of various weight status differed significantly in their leisure-time PA (P<0.001), moderate-intensity PA (P = 0.011) and total PA (P = 0.033).

Conclusions

The patterns and levels of physical activity among adolescents in Nigeria vary according to the adolescents’ age, gender, weight status and SES. These findings have important public health implications for identifying subgroups of Nigerian adolescents that should be targeted for effective physical activity promoting interventions.     

Ethnic Differences in Physical Activity and Inactivity Patterns and Overweight Status

Objective: To examine the relationship between physical activity and inactivity patterns and overweight in U.S. adolescents using baseline and 1-year change in activity and inactivity data. Research Methods and Procedures: Nationally representative data from 12,759 participants (6997 non-Hispanic whites, 2676 non-Hispanic blacks, 2185 Hispanics, and 901 Asians) in the National Longitudinal Study of Adolescent Health (1995 and 1996). Data on moderate to vigorous and low-intensity physical activity, TV/video viewing, and video game/computer use were obtained from questionnaires. Multivariate models assessed the association of overweight (body mass index ≥ 95th percentile Centers for Disease Control and Prevention/National Center for Health Statistics 2000 curves) with initial (and 1-year change) activity and inactivity levels, controlling for age, ethnicity, socioeconomic status, urban residence, cigarette smoking, and region of residence. Results: Overweight prevalence was positively associated with high level TV/video viewing among white boys (odds ratio [OR] = 1.52; 95% confidence interval [1.08 to 2.14]) and girls (OR = 2.45 [1.51 to 3.97]). The odds of overweight decreased with high levels of moderate to vigorous physical activity among white boys (OR = 0.81 [0.76 to 0.87]), non-Hispanic black boys (OR = 0.86 [0.76 to 0.98]) and girls (OR = 0.88 [0.78 to 0.99]), and Hispanic boys (OR = 0.90 [0.83 to 0.97]) and girls (OR = 0.91 [0.84 to 0.99]). Discussion: Predicted probabilities generated from the logistic regression models, which examined the experimental effects of altering hours of TV/video viewing and bouts of moderate to vigorous physical activity, show lower overweight among adolescents who watched less TV per week combined with frequent moderate to vigorous physical activity than those who watched more TV per week combined with fewer bouts of weekly moderate to vigorous physical activity. Predicted probabilities suggest important sex and ethnic differences in these associations.     

Physical Activity Patterns in Normal-Weight and Overweight/Obese Pregnant Women

The aims of the present study were to assess the volume of physical activity (PA) throughout pregnancy in normal-weight vs overweight/obese women, and to investigate which factors may predict compliance to PA recommendations in these women throughout gestation. In 236 pregnant women, 177 normal-weight and 59 overweight/obese (median[IQR] BMI 21.2[19.9–22.8] vs 26.5[25.5–29.0] kg/m2, respectively), medical history, anthropometry and clinical data, including glucose tolerance, were recorded. In addition, pre-pregnancy PA was estimated by the Kaiser questionnaire, while total, walking and fitness/sport PA during pregnancy were assessed by the Physical Activity Scale for the Elderly (PASE) modified questionnaire, at 14–16, 24–28 and 30–32 weeks of gestation. PA volume was very low in the first trimester of pregnancy in both groups of women. However, it increased in the second and third trimester in normal-weight, but not in overweight/obese subjects. Higher pre-pregnancy PA was a statistically significant predictor of being physically active (>150 minutes of PA per week) during all trimesters of gestation. In conclusion, physical activity volume is low in pregnant women, especially in overweight/obese subjects. PA volume increases during pregnancy only in normal-weight women. Pre-pregnancy PA is an independent predictor of achieving a PA volume of at least 150 min per week during pregnancy.