Assessing physical activity intensity by video analysis

Assessing physical activity (PA) is a challenging task and many different approaches have been proposed. Direct observation (DO) techniques can objectively code both the behavior and the context in which it occurred, however, they have significant limitations such as the cost and burden associated with collecting and processing data. Therefore, this study evaluated the utility of an automated video analysis system (CAM) designed to record and discriminate the intensity of PA using a subject tracking methodology. The relative utility of the CAM system and DO were compared with criterion data from an objective accelerometry-based device (Actigraph GT3X+). Eight 10 year old children (three girls and five boys) wore the GT3X+ during a standard basketball session. PA was analyzed by two observers using the SOPLAY instrument and by the CAM system. The GT3X+ and the CAM were both set up to collect data at 30 Hz while the DO was performed every two minutes, with 10 s of observation for each gender. The GT3X+ was processed using cut points by Evanson and the outcome measure was the percentage of time spent in different intensities of PA. The CAM data were processed similarly using the same speed thresholds as were used in establishing the Evenson cut-off points (light: <2 mph; walking: 2-4 mph; very active: >4 mph). Similar outcomes were computed from the SOPLAY default analyses. A chi-square test was used to test differences in the percentage of time at the three intensity zones (light, walking and very active). The Yates' correction was used to prevent overestimation of statistical significance for small data. When compared with GT3X+, the CAM had better results than the SOPLAY. The chi-square test yielded the following pairwise comparisons: CAM versus GT3x+ was χ(2) (5) = 24.18, p < .001; SOPLAY2 versus GT3x+ was χ(2) (5) = 144.44, p < .001; SOPLAY1 versus GT3x+ was χ(2) (5) = 119.55, p < .001. The differences were smaller between CAM and GT3x+, suggesting that the video tracking system provided better agreement than DO. The small sample size precludes a definitive evaluation but the results show that the CAM video system may have promise for automated coding of physical activity behavior.

Influence of different behavioural factors and obesity status on systolic blood pressure among pre-school children

AIM

The aim of this study was to examine the association between sleeping time (SLT), time spent using screen (ST) and weight status with Systolic Blood Pressure (SBP) among pre-school children.

SUBJECTS AND METHODS

The sample comprised 628 pre-school children (50% female), aged 3-6 years-old. SLT and ST were reported by parents. BMI values were categorized according to IOTF. SBP cut points were based on SBP percentiles for age, sex and height. ST was dichotomized according to the following criteria: ≤1 hour vs >1 hour and SLT: ≤10.5 hours vs >10.5 hours. Participants were then categorized into one of four category profiles: Low ST/High SLT; High ST/Low SLT; Low ST/Low SLT and High ST/High SLT.

RESULTS

Children assigned to the High ST/Low SLT group were 2-times more likely to have high SBP values compared to those who were assigned to the Low ST/High SLT group (OR = 2.4; 95% CI = 1.1-5.1). Furthermore, those who were assigned as overweight and obese were more likely to be classified as having elevated BP (OR = 1.8; 95% CI = 1.1-3.2 for overweight and OR = 3.1; 95% CI = 1.6-5.8 for obese, respectively).

CONCLUSION

The data showed that high ST exposure time and low SLT are associated with enhanced blood pressure in children at pre-school.

Parental education and physical activity in pre-school children

BACKGROUND

The purpose of this study was to objectively assess pre-school children's total physical activity (TPA) patterns and compliance with guidelines and to examine differences relative to parental education.

METHODS

The sample consisted on 509 healthy pre-school children, aged 3-6 years recruited from kindergartens located in the metropolitan area of Porto, Portugal. The PA was assessed for 7 consecutive days by accelerometry. For TPA, we followed the guidelines of the National Association for Sport and Physical Education (NASPE) (children who spent at least >120  min per day in active play). For TPA, we calculated the proportion of children who spent at least >120  min per day in active play and moderate-to-vigorous physical activity (MVPA), we calculated the proportion of children who spent at least >60  min per day in active play. Parental education was analysed according to the Portuguese education system.

RESULTS

Children with parents in the highest education level were less active than children from low and middle education level (P ≤ 0.001) in all patterns of PA (week and weekend). Regarding TPA during the week we found that the majority of children from low and middle parental education meet the NASPE guidelines. On the other hand, more than half the children from high parental education did not meet these recommendations (P ≤ 0.001) and MVPA recommendations (P ≤ 0.05). In both recommendations, children from low parental education were twice more likely to meet the recommendations compared with children belonging to high parental education.

CONCLUSION

Parent education was negatively associated with children's daily physical activity patterns and compliance with guidelines.

Relationship of milk intake and physical activity to abdominal obesity among adolescents

What is already known about this subject Diet and physical activity (PA) are recognized as important factors to prevent abdominal obesity (AO). Studies have found an inverse relationship between milk intake or milk products and body weight and/or body fat in children and adolescents. Evidence suggests that low levels of PA are associated with AO in youth. What this study adds Our study explored the combined association of milk intake and PA on AO in adolescents, which are most often studied in isolation. Our findings suggested that adolescents with high milk intakes, regardless of whether they were active or low active, were less likely to have AO. Our findings could have a great epidemiological interest and bring important evidence in the field of AO management among adolescents.

BACKGROUND

Diet and physical activity (PA) are recognized as important factors to prevent abdominal obesity (AO), which is strongly associated with chronic diseases. Some studies have reported an inverse association between milk consumption and AO.

OBJECTIVE

This study examined the association between milk intake, PA and AO in adolescents.

METHODS

A cross-sectional study was conducted with 1209 adolescents, aged 15-18 from the Azorean Archipelago, Portugal in 2008. AO was defined by a waist circumference at or above the 90th percentile. Adolescent food intake was measured using a semi-quantitative food frequency questionnaire, and milk intake was categorized as 'low milk intake' (<2 servings per day) or 'high milk intake' (≥2 servings per day). PA was assessed via a self-report questionnaire, and participants were divided into active (>10 points) and low-active groups (≤10 points) on the basis of their reported PA. They were then divided into four smaller groups, according to milk intake and PA: (i) low milk intake/low active; (ii) low milk intake/active; (iii) high milk intake/low active and (iv) high milk intake/active. The association between milk intake, PA and AO was evaluated using logistic regression analysis, and the results were adjusted for demographic, body mass index, pubertal stage and dietary confounders.

RESULTS

In this study, the majority of adolescents consumed semi-skimmed or skimmed milk (92.3%). The group of adolescents with high level of milk intake and active had a lower proportion of AO than did other groups (low milk intake/low active: 34.2%; low milk intake/active: 26.9%; high milk intake/low active: 25.7%; high milk intake/active: 21.9%, P = 0.008). After adjusting for confounders, low-active and active adolescents with high levels of milk intake were less likely to have AO, compared with low-active adolescents with low milk intake (high milk intake/low active, odds ratio [OR] = 0.412, 95% confidence intervals [CI]: 0.201-0.845; high milk intake/active adolescents, OR = 0.445, 95% CI: 0.235-0.845).

CONCLUSION

High milk intake seems to have a protective effect on AO, regardless of PA level.

Anatomical location for waist circumference measurement in older adults: a preliminary study

BACKGROUND AND OBJECTIVE

Different anatomical locations for measuring waist circumference are described in the literature but the best anatomical location for measuring waist circumference in older adults has yet to be established. Thus, an exploratory study was developed to examine which waist circumference best explains abdominal fat mass in older adults.

METHODS

Waist circumference was measured in the ten different anatomical locations from a sample of 51 older adults. The choice of which waist circumference measurement best associated with abdominal fat mass was evaluated with dual-energy X-ray absorptiometry (DXA) measurement of abdominal fat.

RESULTS

Mean waist circumference values varied from 81.9 (standard deviation (SD): 8.7) cm and 91.5 (SD: 11.2) cm for women and between 95.7 (SD: 8.2) cm and 101.5 (SD: 10.4) cm for men, according to the different anatomical locations. The coefficients of determination of the linear regression model varied from 0.545 to 0.698 (p < 0.001) and the standardised coefficients varied from 0.738 and 0.836 (p < 0.001). The anatomical landmark situated 2.5 cm above the umbilicus was the waist circumference measurement that associated best with abdominal fat mass measured by DXA.

CONCLUSION

This exploratory study contributes to the recognition that the anatomical location where the waist circumference measurement is taken gives considerably different results. The waist circumference measurement 2.5 cm above the umbilicus was the best surrogate measure of abdominal fat in this older adult's sample.

Cardiorespiratory fitness is negatively associated with metabolic risk factors independently of the adherence to a healthy dietary pattern

BACKGROUND AND AIM

Cardiorespiratory fitness (CRF) and diet have been involved as significant factors towards the prevention of cardio-metabolic diseases. This study aimed to assess the impact of the combined associations of CRF and adherence to the Southern European Atlantic Diet (SEADiet) on the clustering of metabolic risk factors in adolescents.

METHODS AND RESULTS

A cross-sectional school-based study was conducted on 468 adolescents aged 15-18, from the Azorean Islands, Portugal. We measured fasting glucose, insulin, total cholesterol (TC), HDL-cholesterol, triglycerides, systolic blood pressure, waits circumference and height. HOMA, TC/HDL-C ratio and waist-to-height ratio were calculated. For each of these variables, a Z-score was computed by age and sex. A metabolic risk score (MRS) was constructed by summing the Z scores of all individual risk factors. High risk was considered when the individual had ≥ 1 SD of this score. CRF was measured with the 20 m-Shuttle-Run-Test. Adherence to SEADiet was assessed with a semi-quantitative food frequency questionnaire. Logistic regression showed that, after adjusting for potential confounders, unfit adolescents with low adherence to SEADiet had the highest odds of having MRS (OR = 9.4; 95%CI:2.6-33.3) followed by the unfit ones with high adherence to the SEADiet (OR = 6.6; 95% CI: 1.9-22.5) when compared to those who were fit and had higher adherence to SEADiet.

CONCLUSIONS

Unfit adolescents showed higher odds of having high MRS, regardless of the adherence to SEADiet suggesting that high CRF may overcome the deleterious effects of low adherence to a healthy dietary pattern in adolescents.

Clustering of physical inactivity in leisure, work, commuting and household domains among Brazilian adults

OBJECTIVES

To identify the clustering of physical inactivity in leisure, work, commuting and household contexts, and the sociodemographic factors associated with the clustering of inactive behaviour in different domains among Brazilian adults.

STUDY DESIGN

Cross-sectional population-based study.

METHODS

The study was performed in Florianopolis, capital of Santa Catarina, one of the southern states of Brazil, from September 2009 to January 2010. Adults aged 20-59 years were interviewed. Physical inactivity in each domain was defined as non-participation in specific physical activities, using a validated Brazilian questionnaire. Clustering of physical inactivity was identified by the ratio between observed prevalence and expected prevalence of 16 different combinations. Multinomial logistic regression was used in the analysis of sociodemographic factors associated with clustering of physical inactivity.

RESULTS

Of the 1720 interviewees, the greatest differences between the observed and expected proportions were observed in simultaneous physical inactivity in the leisure and household domains for men, and physical inactivity in the leisure domain alone for women (59% and 88%, respectively); these differences were higher than expected if the behaviours were independent. Physical inactivity in two or more domains was observed more frequently in men and in individuals with a higher per-capita family income. Ageing was associated with physical inactivity in three or four domains.

CONCLUSIONS

Physical inactivity was observed in different domains according to gender. Men and older individuals with a higher per-capita family income were more likely to exhibit physical inactivity when all domains were considered together.

Cardiorespiratory fitness associates with metabolic risk independent of central adiposity

This study sought to analyze the associations between cardiorespiratory fitness (CRF), waist circumference (WC) and metabolic risk in children and adolescents. Participants were 633 subjects (58.7% girls) ages 10-18 years. Metabolic risk score (MRS) was calculated from HDL-cholesterol, triglycerides, fasting glucose and mean arterial pressure. MRS was dichotomized into low and high metabolic risk (HMRS). CRF was defined as the maximal oxygen uptake (VO₂max) estimated from the 20 m Shuttle Run Test. The first quartile of CRF was set as the low fitness group. The fourth quartile of WC was defined as high central adiposity. With adjustments for age, sex and WC, CRF was correlated with MRS (r=-0.095; p<0.05). WC was correlated with MRS (r=0.150; p<0.001) after adjustments for age, sex and CRF. Participants who had low fitness levels, presented higher levels of MRS (p<0.001) compared to those who were fit, even after adjustment for age, sex and WC. In comparison with subjects who were fit with normal central adiposity, an increased odds ratio (OR) for being at HMRS was found for participants who were of low fitness level with high central adiposity (OR=2.934; 95%CI= 1.690-5.092) and for those who were of low fitness with normal central adiposity (OR=2.234; 95%CI=1.116-4.279). Results suggest that CRF relates to MRS independently of central adiposity.

Chitosan/bioactive glass nanoparticle composite membranes for periodontal regeneration

Barrier membranes are used in periodontal applications with the aim of supporting periodontal regeneration by physically blocking migration of epithelial cells. The present work proposes a combination of chitosan (CHT) with bioactive glass nanoparticles (BG-NPs) in order to produce a novel guided tissue and bone regeneration membrane, fabricated by solvent casting. The CHT/BG-NP nanocomposite membranes are characterized in terms of water uptake, in mechanical tests, under simulated physiological conditions and in in vitro bioactivity tests. The addition of BG-NPs to CHT membranes decreased the mechanical potential of these membranes, but on the other hand the bioactivity improved. The membranes containing the BG-NPs induced the precipitation of bone-like apatite in simulated body fluid (SBF). Biological tests were carried out using human periodontal ligament cells and human bone marrow stromal cells. CHT/BG-NP composite membranes promoted cell metabolic activity and mineralization. The results indicate that the CHT/BG-NP composite membrane could potentially be used as a temporary guided tissue regeneration membrane in periodontal regeneration, with the possibility to induce bone regeneration.

Milk intake is inversely related to body mass index and body fat in girls

Dairy foods comprise a range of products with varying nutritional content. The intake of dairy products (DPs) has been shown to have beneficial effects on body weight and body fat. This study aimed to examine the independent association between DP intake, body mass index (BMI), and percentage body fat (%BF) in adolescents. A cross-sectional, school-based study was conducted with 1,001 adolescents (418 boys), ages 15-18 years, from the Azorean Archipelago, Portugal. Anthropometric measurements were recorded (weight and height), and %BF was assessed using bioelectric impedance analysis. Adolescent food intake was measured using a self-administered, semiquantitative food frequency questionnaire. Data were analyzed separately for girls and boys, and separate multiple linear regression analysis was used to estimate the association between total DP, milk, yogurt, and cheese intake, BMI, and %BF, adjusting for potential confounders. For boys and girls, respectively, total DP consumption was 2.6 ± 1.9 and 2.9 ± 2.5 servings/day (P = 0.004), while milk consumption was 1.7 ± 1.4 and 2.0 ± 1.7 servings/day (P = 0.001), yogurt consumption was 0.5 ± 0.6 and 0.4 ± 0.7 servings/day (P = 0.247), and cheese consumption was 0.4 ± 0.6 and 0.5 ± 0.8 servings/day (P = 0.081). After adjusting for age, birth weight, energy intake, protein, total fat, sugar, dietary fiber, total calcium intake, low-energy reporters, parental education, pubertal stage, and physical activity, only milk intake was negatively associated with BMI and %BF in girls (respectively, girls: β = -0.167, P = 0.013; boys: β = -0.019, P = 0.824 and girls: β = -0.143, P = 0.030; boys: β = -0.051, P = 0.548).

CONCLUSION

We found an inverse association between milk intake and both BMI and %BF only in girls.

[Digital ulcers in systemic sclerosis: use of endotheline antagonists]

INTRODUCTION

Systemic sclerosis (SSc) is a systemic disease, characterized by fibrosis and vasculopathy, with variable internal organ involvement. Skin is very often involved, namely digital ulcers (DU), seldom treatment resistant, responsible for important functional limitation. The DU can evolve from sclerodactily with superficial ulcers, isquemic lesions, deep necrosis, gangrene, loss of tissue, and consequently, to finger amputation.

METHODS

The authors describe the case of a 36 year old female patient, with SSc diagnosed 6 years previously, with skin, lung and gut manifestations. The patient showed uncontrolled Raynaud's phenomenon (RF), despite the adequate treatment using nifedidpine and general local warming measures, with progressively worsening DU and isquemia, especially in cold seasons. Bosentan, 62.5 mg twice daily was started, and a significant improvement in the peripheral isquemic lesions was achieved. The ulcers' healing was fast, the patient totally recovered function and regained quality of life, and no further lesions developed.

CONCLUSION

The authors review the RF and DU in SSc, as well as the use of bosentan, an endotheline receptor antagonist, and its indications. Although it is not formally approved, the use of bosentan in SS has shown benefits in reducing the incidence of DU, and despite no influence in the healing process, this drug prevents the development of new lesions.