Pilot evaluation of an interactive multimedia platform to provide nutrition education to Portuguese adolescents.

BACKGROUND: Obesity prevalence has been rising worldwide and currently is one of the most serious public health problems. Nutrition literacy is important to the development of healthier habits that could help prevent and stem obesity and overweight. The aim of this study was to evaluate the impact of using a multimedia web platform to provide nutrition education to Portuguese adolescents. METHODS: The intervention consisted in a two-week period in which students (n = 1291) had access to an interactive multimedia web platform with nutritional content, and designed for a self-paced learning experience. Students completed a knowledge questionnaire at baseline and immediately after the end of the intervention. RESULTS: The results obtained revealed that 85.8% of the students increased their nutrition knowledge. No gender differences were observed post-intervention. There were significant differences in the knowledge acquisition regarding age (P < 0.001). The baseline knowledge seemed to influence the learning process. CONCLUSIONS: Overall, the intervention had a positive impact. The preliminary results observed will be important for the improvement of the intervention, though they need to be confirmed by further research. Nevertheless, it is safe to say that technology-based assets can be important tools to incorporate and complement health-related interventions in schools.

Association between ACE D allele and elite short distance swimming.

The influence of ACE gene on athletic performance has been widely explored, and most of the published data refers to an I/D polymorphism leading to the presence (I allele) or absence (D allele) of a 287-bp sequence in intron 16, determining ACE activity in serum and tissues. A higher I allele frequency has been reported among elite endurance athletes, while the D allele was more frequent among those engaged in more power-orientated sports. However, on competitive swimming, the reproducibility of such associations is controversial. We thus compared the ACE genotype of elite swimmers with that of non-elite swimming cohort and of healthy control subjects. We thus sought an association of the ACE genotype of elite swimmers with their competitive distance. 39 Portuguese Olympic swimming candidates were classified as: short (<200 m) and middle (400-1,500 m) distance swimmers, respectively. A group of 32 non-elite swimmers were studied and classified as well, and a control group (n = 100) was selected from the Portuguese population. Chelex 100 was used for DNA extraction and genotype was determined by PCR-RFLP methods. We found that ACE genotype distribution and allelic frequency differs significantly by event distance only among elite swimmers (P < or = 0.05). Moreover, the allelic frequency of the elite short distance swimmers differed significantly from that of the controls (P = 0.021). No associations were found between middle distance swimmers and controls. Our results seem to support an association between the D allele and elite short distance swimming.

Angiotensin-converting enzyme genotype affects skeletal muscle strength in elite athletes.

Previous studies have associated angiotensin-converting enzyme (ACE) D allele with variability in the skeletal muscle baseline strength, though conclusions have been inconsistent across investigations. The purpose of this study was to examine the possible association between ACE genotype and skeletal muscle baseline strength in elite male and female athletes involved in different event expertise. A group of 58 elite athletes, designated as Olympic candidates, were studied: 35 swimmers (19 males and 16 females, 18.8 ± 3.2 years) and 23 triathletes (15 males and 8 females, 18.7 ± 3.0 years). The athletes were classified as: short (≤ 200m) and middle (400m to 1500m) distance athletes, respectively. For each subject the grip strength in both hands was measure using an adjustable mechanical hand dynamometer. The maximum height in both squat jump (SJ) and counter movement jump (CMJ) were also assessed, using a trigonometric carpet (Ergojump Digitime 1000; Digitest, Jyvaskyla, Finland). DNA extraction was obtained with Chelex 100(®) and genotype determination by PCR-RFLP methods. Both males and females showed significantly higher right grip strength in D allele carriers compared to II homozygote's. We found that allelic frequency differs significantly by event distance specialization in both genders (p < 0.05). In fact, sprinter D allele carriers showed the superior scores in nearly all strength measurements (p < 0.05), in both genders. Among endurance athletes, the results also demonstrated that female D allele carriers exhibited the higher performance right grip and CMJ scores (p < 0.05). In conclusion, the ACE D allele seems associated with skeletal muscle baseline strength in elite athletes, being easily identified in females. Key pointsDD homozygote's and D allele carriers from both genders shows significantly higher right grip strength.Right grip strength remains significantly higher in the D allele carrier's female endurance group.Female's D allele carriers exhibited the higher performance counter-movement jump scores.ACE genotype effects in skeletal-muscle strength are diverse by gender, being easily identified in females.

Behavioral, contextual and biological factors associated with obesity during adolescence: A systematic review.

INTRODUCTION/OBJECTIVE: Adolescence is a critical period for the development of obesity. Obesity arises from a complex interaction between several factors, which are not yet fully understood. Therefore, the purpose of this review was to identify and assess the peer-reviewed scientific literature on the behavioral, contextual and biological factors associated with obesity in adolescents. METHODS: PubMed and Scopus were systematically searched to identify prospective cohort studies concerning the relation between behavioral, contextual and biological factors and obesity in adolescents aged 10 to 18 years. RESULTS: 40 studies published between the year 2000 and 2018 were included. A positive consistent association between genetic factors and obesity during adolescence was found. Also, there is evidence to support the association between socioeconomic status and obesity. There was conflicting evidence for the contribution of dietary intake, physical activity, sedentary behavior, sleep, food store environment, school food environment. For the remaining factors no associations were found, or no conclusions could be drawn due to the limited number of studies identified. CONCLUSIONS: Further prospective studies that assess multiple obesity determinants simultaneously and use state-of-art measures are warranted to aid in the development of effective strategies and interventions to prevent obesity during adolescence.

Secular Trends in Anthropometrics and Physical Fitness of Young Portuguese School-Aged Children.

INTRODUCTION: The purpose of this study was to analyze secular trends in anthropometrics and physical fitness of Portuguese children. MATERIAL AND METHODS: A group of 1819 students (881 boys and 938 girls) between 10 and 11 years old was assessed in their 5th and 6th scholar grade throughout a 20 years' time-frame. ANCOVA models were used to analyze variations in anthropometrics (height, weight and body mass index) and physical fitness (sit and reach, curl-up, horizontal jump and sprint time) across four quinquennials (1993 - 1998; 1998 - 2003; 2003 - 2008; 2008 - 2013). RESULTS: Secular trends showed the presence of heavier boys and girls with higher body mass index in the 5th and 6th grade throughout the last 20 years. There was also a presence of taller girls but just until the 3rd quinquennial. Both boys and girls were able to perform better on the core strength test and sprint time but become less flexible over the years. Mean jumping performance remained unchanged for both genders. DISCUSSION: The present study provides novel data on anthropometrics and physical fitness trends over the last two decades in young Portuguese children, consistent with the results reported in other developed countries. CONCLUSION: Evidence for the start of a positive secular trend in body mass index and in some physical fitness components over the last two decades among the Portuguese youth.

Introdução: Analisar as tendências seculares ao nível da antropometria e aptidão física das crianças portuguesas. Material e Métodos: Um grupo de 1819 crianças (881 rapazes e 938 raparigas) entre os 10 e os 11 anos de idade, foi avaliado no 5º e 6º ano de escolaridade durante 20 anos. A ANCOVA foi usada para analisar as variações de antropometria (índice de massa corporal, peso e altura) e aptidão física (sentar e alcançar, força abdominal, salto horizontal e corrida de velocidade) durante quatro quinquénios (1993 - 1998; 1998 - 2003; 2003 - 2008 e 2008 - 2013). Resultados: As tendências seculares mostraram a presença de crianças mais pesadas e com um índice de massa corporal mais elevado ao longo dos últimos 20 anos. Verificou-se também a presença de raparigas mais altas, mas só até ao terceiro quinquénio. Ambos os géneros melhoraram o desempenho nos testes de força abdominal e corrida de velocidade mas pioram a sua capacidade de flexibilidade ao longo dos anos. O desempenho no salto horizontal permaneceu inalterado em ambos os géneros. Discussão: Este estudo fornece novos dados sobre a tendência dos registos antropométricos e de aptidão física nos últimos 20 anos em crianças Portuguesas, sendo consistente com as tendências reportadas sobre outros países desenvolvidos. Conclusão: Os resultados sugerem uma tendência positiva nos últimos 20 anos no índice de massa corporal e em alguns componentes da aptidão física em crianças Portuguesas.