Anders Raustorp

How many steps/day are enough? for children and adolescents

Worldwide, public health physical activity guidelines include special emphasis on populations of children (typically 6-11 years) and adolescents (typically 12-19 years). Existing guidelines are commonly expressed in terms of frequency, time, and intensity of behaviour. However, the simple step output from both accelerometers and pedometers is gaining increased credibility in research and practice as a reasonable approximation of daily ambulatory physical activity volume. Therefore, the purpose of this article is to review existing child and adolescent objectively monitored step-defined physical activity literature to provide researchers, practitioners, and lay people who use accelerometers and pedometers with evidence-based translations of these public health guidelines in terms of steps/day. In terms of normative data (i.e., expected values), the updated international literature indicates that we can expect 1) among children, boys to average 12,000 to 16,000 steps/day and girls to average 10,000 to 13,000 steps/day; and, 2) adolescents to steadily decrease steps/day until approximately 8,000-9,000 steps/day are observed in 18-year olds. Controlled studies of cadence show that continuous MVPA walking produces 3,300-3,500 steps in 30 minutes or 6,600-7,000 steps in 60 minutes in 10-15 year olds. Limited evidence suggests that a total daily physical activity volume of 10,000-14,000 steps/day is associated with 60-100 minutes of MVPA in preschool children (approximately 4-6 years of age). Across studies, 60 minutes of MVPA in primary/elementary school children appears to be achieved, on average, within a total volume of 13,000 to 15,000 steps/day in boys and 11,000 to 12,000 steps/day in girls. For adolescents (both boys and girls), 10,000 to 11,700 may be associated with 60 minutes of MVPA. Translations of time- and intensity-based guidelines may be higher than existing normative data (e.g., in adolescents) and therefore will be more difficult to achieve (but not impossible nor contraindicated). Recommendations are preliminary and further research is needed to confirm and extend values for measured cadences, associated speeds, and MET values in young people; continue to accumulate normative data (expected values) for both steps/day and MVPA across ages and populations; and, conduct longitudinal and intervention studies in children and adolescents required to inform the shape of step-defined physical activity dose-response curves associated with various health parameters.

Activity levels and body mass index of children in the United States, Sweden, and Australia.

PURPOSE Assess the physical activity and body mass index (BMI) levels of children in the United States, Sweden, and Australia. METHODS A total of 1954 children, 6-12 yr old (711 American, 563 Australian, and 680 Swedish) wore sealed pedometers for four consecutive days. Height and weight measures were obtained. RESULTS Descriptive data for step counts and BMI by sex, age, and country were calculated to determine activity levels and BMI. Three-way multivariate ANOVA for step counts and BMI between countries at each age and sex found that, in general, the Swedish children were significantly more active than the Australian and American children, and the American children were significantly heavier than the Australian and Swedish children. For boys, the mean step counts ranged from 15673 to 18346 for Sweden, 13864 to 15023 for Australia, and 12554 to 13872 for America. For girls, the mean step counts ranged from 12041 to 14825 for Sweden, 11221 to 12322 for Australia, and 10661 to 11383 for America. The activity curve is somewhat level during the preadolescent years. The rate of increase in BMI with age is much greater in the American children than in the Swedish or Australian children. The percent of American, Swedish, and Australian boys classified as overweight/obese was 33.5, 16.6, and 15.8, respectively. The percent of American, Swedish, and Australian girls classified as overweight/obese was 35.6, 16.8, and 14.4, respectively. Correlation analysis found few significant negative relationships between step counts and BMI. CONCLUSIONS American children tend to be the least active and heaviest with the greatest rate of increase in BMI. The Swedish children are the most active group followed by Australia. Swedish and Australian children maintain lower BMI throughout their prepubescent years than do the American children who have a greater percentage who are classified as overweight.

Pain Assessment with Different Intensity Scales in Response to Loading of Joint Structures.

&NA; The purpose of the present study was to compare intensity levels assessed on Borgs Category Scale for Ratings of Perceived Pain (BRPP) (1982) (a verbal scale using adjectives and adverbs combined with the numbers 0–10), with assessments on the Visual Analogue Scale (VAS) (a 10 cm horizontal line). Eight healthy subjects volunteered in an experimental study, where pain was provoked by load on passive soft tissue elbow joint structures. Each subject participated 4 times on different occasions in the same experimental set‐up, which was divided into six 2 min periods; 3 periods with load induced by applied external weights causing load moments of 3.4 Nm, 4.5 Nm and 6.8 Nm plus that induced by the weight of the lower arm and hand (average 2.9 Nm), followed by 3 periods without external weights. Each series consisted of 12 assessments given during the last 10 sec period of each minute on either the BRPP or the VAS. No significant difference was found between the first and second time a scale was used by the same subject and none between the assessments on the VAS and the BRPP. Intensity levels of pain increased with load and time and decreased after reduction of the load moments. It is concluded that both scales can be used to reliably assess intensity levels of perceived pain elicited by loading joint structures. Intensity levels, as assessed on both scales, are associated with applied external load and time for exposure.

Physical activity and self‐perception in school children assessed with the Children and Youth – Physical Self‐Perception Profile

Aim: This study validated the Swedish translation of the Children and Youth – Physical Self‐Perception Profile (CY – PSPP) scale and examined the relation between physical self‐Perception and daily physical activity as well as the relationship between physical self‐perception and body mass index (BMI) among Swedish school children.

Physical activity level and body mass index among schoolchildren in south-eastern Sweden.

Aim: The aims of this study were to identify current levels of physical activity and to study the relationship between physical activity and body mass index (BMI) using international cut‐off points. Methods: 871 children, aged 7–14 y, were measured for height and weight and the activity levels were analysed using pedometers to measure mean step counts for 4 consecutive days. Results: Step counts were significantly higher in boys than in girls, and showed stability over age and large in‐group differences. BMI showed that 13.2% of the boys and 14.5% of the girls were overweight and 4.5% of both boys and girls were obese. Analysis of step counts and BMIs for boys and girls revealed no significant correlations in any age group.

Comparison of pedometer and accelerometer measures of physical activity during preschool time on 3- to 5-year-old children

Aims:  To compare pedometer steps with accelerometer counts and to analyse minutes of engagement in light, moderate and vigorous physical activity in 3‐ to 5‐year‐old children during preschool time.

Secular trends of pedometer-determined physical activity in Swedish school children

Aim: To explore the secular trends (time change) of pedometer‐determined physical activity (steps per day) in Swedish schoolchildren 7–9 years of age from 2000 to 2006. It was an additional aim to examine the secular trends in body mass index.

Physical activity, body composition and physical self-esteem: a 3-year follow-up study among adolescents in Sweden.

Aims: To measure physical activity by means of daily pedometer steps, body composition, expressed as body mass index (BMI) and bioelectrical impedance as percent body fat, and perceived physical self‐esteem and additionally, to evaluate eventual predictors for a healthy lifestyle i.e., highly physically active, normal weighted and a high physical self‐esteem in a follow‐up group.

The quality of the outdoor environment influences childrens health- a cross sectional study of preschools

To test how the quality of the outdoor environment of child day care centres (DCCs) influences childrens health.

Reduction in pedometer-determined physical activity in the adult Danish population from 2007 to 2012.

Aims: To examine the development in pedometer-determined physical activity from 2007–2008 to 2011–2012 in the adult Danish population. Methods: The study population comprised two random samples of 18–75-year-old individuals who took part in cross-sectional studies in 2007–2008 (n=224) and 2011–2012 (n=1515). Pedometer data (sealed Yamax SW 200) were obtained for seven consecutive days. Data for 1624 participants (48.2% men) were included in the analysis. An overall step-defined activity level was examined based on a graduated step index (sedentary, low active, somewhat active, active, highly active). The pedometer-determined outcomes were analysed using regression models. Results: A borderline significant decline (p=0.077) from 8788 to 8341 steps/day (−446 (95% confidence intervals −50, 943)) was found between 2007–2008 and 2011–2012. Furthermore, a 23.7% (95% confidence intervals −41.7%, −0.1%) lower overall step-defined activity level was observed in 2011–2012 compared to 2007–2008. These changes were primarily due to a reduced level of activity among women. The proportion of individuals taking ⩾10,000 steps/day decreased non-significantly from 34.8% to 29.3%, whereas the proportion taking <5000 steps/day did not differ between survey periods. Conclusions: This nationally representative survey suggests an overall reduction in the physical activity level among Danish adults. The reduction was due to a shift in the population distribution from higher to lower levels of activity. If this shift is true, it is worrying from a public health perspective. Our study result needs, however, to be confirmed by other population studies.