Although there is some evidence that total dietary antioxidant capacity (TDAC) is inversely associated with the presence of obesity, no longitudinal studies have been performed investigating the effect of TDAC on comprehensive measures of body composition over time. In this study, we included 4595 middle-aged and elderly participants from the Rotterdam Study, a population-based cohort. We estimated TDAC among these individuals by calculating a ferric reducing ability of plasma (FRAP) score based on data from food-frequency questionnaires. Body composition was assessed by means of dual X-ray absorptiometry at baseline and every subsequent 3-5 years. From these data, we calculated fat mass index (FMI), fat-free mass index (FFMI), android-to-gynoid fat ratio (AGR), body fat percentage (BF%) and body mass index (BMI). We also assessed hand grip strength at two time points and prevalence of sarcopenia at one time point in a subset of participants. Data were analyzed using linear mixed models or multinomial logistic regression models with multivariable adjustment. We found that higher FRAP score was associated with higher FFMI (0.091 kg/m2 per standard deviation (SD) higher FRAP score, 95% CI 0.031; 0.150), lower AGR (-0.028, 95% CI -0.053; -0.003), higher BMI (0.115, 95% CI 0.020; 0.209) and lower BF% (-0.223, 95% CI -0.383; -0.064) across follow-up after multivariable adjustment. FRAP score was not associated with hand grip strength or sarcopenia. Additional adjustment for adherence to dietary guidelines and exclusion of individuals with comorbid disease at baseline did not change our results. In conclusion, dietary intake of antioxidants may positively affect the amount of lean mass and overall body composition among the middle-aged and elderly.
OBJECTIVE: The aim of this study was to explore the longitudinal relationship between sitting time on a working day and vitality, work performance, presenteeism, and sickness absence.METHODS: At the start and end of a five-month intervention program at the workplace, as well as 10 months after the intervention, sitting time and work-related outcomes were measured using a standardized self-administered questionnaire and company records. Generalized linear mixed models were used to estimate the longitudinal relationship between sitting time and work-related outcomes, and possible interaction effects over time.RESULTS: A significant and sustainable decrease in sitting time on a working day was observed. Sitting less was significantly related to higher vitality scores, but this effect was marginal (b = -0.0006, P = 0.000).CONCLUSIONS: Our finding of significant though marginal associations between sitting time and important work-related outcomes justifies further research.
Previous research has suggested that professional youth work settings empower socially vulnerable youngsters, strengthening their personal development and social participation. It is expected that youth work can prevent personal and social problems of youngsters, which may have longer term positive social returns. How the underlying methodical way of acting of youth workers contributes to prevention-focused outcomes remains unclear. This article presents a four-wave longitudinal cohort study (16 months) that investigated longitudinal associations between 12 individual methodical principles that youth workers apply in interactions with youngsters and four prevention-focused outcomes: prosocial skills, self-mastery, social network and civic participation. The sample consisted of 1,597 Dutch youngsters with a mean age of 16.5 years (SD = 3.60). Findings: Linear mixed models analysis found that all individual methodical principles were longitudinally associated with one or more outcome. The strongest associations were observed with regard to prosocial skills and civic participation. Depending on the outcome measure, methodical principles seem to be more effective for boys, for youngsters who participate for 3 years or longer in youth work settings and for youngsters between 10 and 19 years old. With regard to the effect of methodical principles on improving self-mastery, 9 of the 12 principles appeared to play no positive role in increasing self-mastery of youngsters. Applications: This study provides youth workers with a better understanding of which methodical principles are positively associated with prevention-focused outcomes as well as reinforcing the evidence-based practice of professional youth work.
