Vitor Pires Lopes, Pedro Magalhães, José Bragada and Catarina Vasques
Several methods exist to asses and control physical intensity levels of subjects engaged in physical activities programs, accelerometry is a method that could be easily used in the field. The purposes were: to calibrate Actigraph in middle-aged to old obese/overweight and DM2 adult patients; and to determine the threshold counts for sedentary, light, moderate, and vigorous physical activity (PA).
Sample comprise 26 participants (62.6 ± 6.5 years of age) of both gender. Counts and VO2 were simultaneously assessed during: resting, seating, standing, walking at 2.5 km·h−1, 5 km·h−1, and 6 km·h−1. A hierarchical linear model was used to derive a regression equation between MET and counts. Receiver operating characteristics (ROC) analysis was used to define thresholds for PA levels.
The regression equation was: MET = 1.388400490262 + 0.001312683420044 (counts·min−1), r = .867. The threshold counts for sedentary-light, light-moderate and moderate-vigorous PA were: 200, 1240, 2400 counts·min−1 respectively.
The Actigraph is a valid and useful device for the assessment of the amount of time spent in each PA intensity levels in obese/overweight and DM2 middle-aged to old adult patients.
Catarina Vasques, Pedro Magalhães, António Cortinhas, Paula Mota, José Leitão and Vitor Pires Lopes
This meta-analysis study aims to assess the efficacy of school-based and after-school intervention programs on the BMIs of child and adolescents, addressing the correlation between some moderating variables.
We analyzed 52 studies (N = 28,236) published between 2000–2011.
The overall effect size was 0.068 (P < .001), school (r = .069) and after-school intervention (r = .065). Programs conducted with children aged between 15–19 years were the most effective (r = .133). Interventions programs with boys and girls show better effect sizes (r = .110) than programs that included just girls (r = .073). There were no significant differences between the programs implemented in school and after-school (P = .770). The effect size was higher in interventions lasting 1 year (r = .095), with physical activity and nutritional education (r = .148), and that included 3–5 sessions of physical activity per week (r = .080). The effect size also increased as the level of parental involvement increased.
Although of low magnitude (r = .068), the intervention programs had a positive effect in prevention and decreasing obesity in children. This effect seems to be higher in older children’s, involving interventions with physical activity and nutritional education combined, with parent’s participation and with 1-year duration. School or after-school interventions had a similar effect.