Longitudinal study of physical activity in Spanish young adolescents: weight status and gender differences / Estudio longitudinal de la actividad física en adolescentes españoles: Diferencias por estatus de peso y género / Estudo longitudinal da atividade física em adolescentes espanhóis: diferenças por status de peso e de gênero

Past research indicates there are marked declines in physical activity (PA) during adolescence. Recent studies are offering new insights. This longitudinal study investigates changes in intensities of PA (moderate-to-vigorous vs. light), by gender and weight-status, in a sample of Spanish adolescents. Students, on average 13.9 years-old (N=833 at baseline), were followed- up a year and two years later (N=474 provided data at the three time points). Self-reported PA was recorded. Analyses revealed that PA prevalence is low, although, overtime, slight increments were observed. Girls showed higher increments in moderate-to-vigorous physical activity (MVPA); boys showed higher increments in light physical activity (LPA). Investigating by weight-status, normal-weight boys showed increments over time in LPA; no changes observed for normal-weight girls. Overweight/obese girls increased their total PA (TPA) and MVPA; overweight/obese boys increased their LPA. Underweight boys and girls decreased their TPA. Interventions targeting specific intensities of PA may be beneficial for different groups based on their gender and weight status

Investigaciones anteriores indican que hay marcadas disminuciones en la actividad física (AF) durante la adolescencia. Estudios más recientes ofrecen nuevos conocimientos. Este estudio longitudinal investiga los cambios en las intensidades de la AF (moderada a vigorosa versus ligera), por género y estatus de peso, en una muestra de adolescentes españoles. Los estudiantes, que en la línea base tenían un promedio de 13.9 años de edad (N = 833 al inicio), fueron seguidos uno y dos años más tarde (N = 474 proporcionaron datos en las tres mediciones de tiempo). La AF fue auto-informada. Los análisis revelaron que la prevalencia de AF es baja, aunque, a lo largo del tiempo, se observaron incrementos leves. Las niñas mostraron incrementos más altos en la actividad física moderada a vigorosa (AFMV); los niños mostraron mayores incrementos en la actividad física leve (AFL). Investigando por estatus de peso, los niños de peso normal mostraron incrementos a lo largo del tiempo en AFL; No se observaron cambios en las niñas de peso normal. Las niñas con sobrepeso/obesidad aumentaron su AF total (AFT) y AFMV; Los niños con sobrepeso / obesidad aumentaron su AFL. Los niños y niñas con bajo peso disminuyeron su AFL. Las intervenciones dirigidas a intensidades específicas de AF pueden ser beneficiosas para diferentes grupos según su género y estatus de peso

Pesquisas anteriores indicam que há declínios acentuados na atividade física (AF) durante a adolescência. Estudos recentes estão oferecendo novos conhecimentos. Este estudo longitudinal investiga mudanças nas intensidades de AF (moderada a vigorosa vs. leve), por sexo e status de peso, em uma amostra de adolescentes espanhóis. Os alunos, em média, 13,9 anos de idade (N = 833 no início do estudo), foram acompanhados por um ano e dois anos mais tarde (N = 474 dados fornecidos nos três pontos de tempo). A AF autorreferida foi registrada. Análises revelaram que a prevalência de AF é baixa, embora, horas extras, pequenos incrementos tenham sido observados. Meninas apresentaram maiores incrementos na atividade física moderada a vigorosa (AFMV); os meninos apresentaram maiores incrementos na atividade física leve (AFL). Investigando por peso-status, meninos com peso normal mostraram incrementos ao longo do tempo em AFL; nenhuma alteração observada para meninas com peso normal. Meninas com sobrepeso / obesidade aumentaram seu AF total (AFT) e AFMV; meninos com sobrepeso / obesos aumentaram seu AFL. Meninos e meninas com baixo peso diminuíram o AFT. Intervenções direcionadas a intensidades específicas de AF podem ser benéficas para diferentes grupos com base em seu gênero e status de peso

Body image dissatisfaction, physical activity and screen-time in Spanish adolescents.

This cross-sectional study contributes to the literature on whether body dissatisfaction is a barrier/facilitator to engaging in physical activity and to investigate the impact of mass-media messages via computer-time on body dissatisfaction. High-school students ( N = 1501) reported their physical activity, computer-time (homework/leisure) and body dissatisfaction. Researchers measured students' weight and height. Analyses revealed that body dissatisfaction was negatively associated with physical activity on both genders, whereas computer-time was associated only with girls' body dissatisfaction. Specifically, as computer-homework increased, body dissatisfaction decreased; as computer-leisure increased, body dissatisfaction increased. Weight-related interventions should improve body image and physical activity simultaneously, while critical consumption of mass-media interventions should include a computer component.

Increasing food acceptance in the home setting: a randomized controlled trial of parent-administered taste exposure with incentives.

BACKGROUND: The use of rewards to encourage children to eat healthily is controversial. However, researcher-led interventions have shown that incentives combined with taste exposure can increase both intake and liking. To date, this has not been tested in the home setting. OBJECTIVES: The objectives were to test the hypothesis that parent-administered repeated taste exposures to an initially disliked vegetable combined with reward will increase children's liking and intake and to compare the effects of tangible and social rewards. DESIGN: In this randomized controlled trial, families with children aged 3-4 y (n = 173) were randomly assigned to exposure + tangible reward (sticker), exposure + social reward (praise), or no-treatment control conditions after a pretest assessment in which a target vegetable was selected for each child. In the intervention groups, parents offered their children 12 daily tastes of the vegetable, giving either praise or a sticker for tasting. No specific advice was given to the control group. Assessments of intake and liking of the target vegetable were conducted by researchers immediately after the intervention period and 1 and 3 mo later. RESULTS: Children who received exposure + tangible rewards increased their intake (P = 0.001) and liking (P = 0.001) of their target vegetable significantly more than did children in the control group. Differences were maintained at the 3-mo follow-up (intake: P = 0.005; liking: P = 0.001). Increases in intake and liking in the exposure + social reward group were not significantly different from the control group. CONCLUSION: The findings of this home-based study support parental use of tangible rewards with repeated taste exposures to improve children's diets. This trial is registered as ISRCTN42922680.

Facilitating or undermining? The effect of reward on food acceptance. A narrative review.

Using rewards in child feeding is commonplace and viewed as effective by parents, although some express concern about using 'bribery'. Psychological and economic theorists emphasize the beneficial effects of rewards in enhancing performance, although, there is evidence that the offer of rewards undermines intrinsic motivation and decreases enjoyment of the rewarded task. In the food domain, results have been mixed, but this may be explained, at least partly in terms of the measured outcome (liking vs intake) and the initial level of motivation towards the target foods (liked vs disliked). Where intake is the outcome, rewards have had broadly positive effects, but when it is liking, rewards can have negative effects if the target food is already liked. Another issue concerns the type of reward offered. While offering food as a reward appear to be universally negative, there is evidence to suggest that non-food tangible rewards (e.g., stickers), or non-tangible rewards (praise) can be highly effective in encouraging children to taste new or less liked foods sufficiently often to benefit from the 'mere exposure' effect. We suggest that the judicious use of rewards may facilitate children's acceptance of healthy foods.

Eating for pleasure or profit: the effect of incentives on children's enjoyment of vegetables.

Parents commonly use rewards to encourage children to eat healthfully, but this practice remains controversial because rewards are suspected of undermining children's intrinsic motivation. A cluster-randomized trial examined children's acceptance of a disliked vegetable over 12 daily taste exposures. These exposures were paired with a tangible reward, a social reward, or no reward, and the findings were compared with the results from a no-treatment control condition. Liking and intake of the vegetable were assessed in a free-choice consumption task at preintervention, postintervention, 1 month after intervention, and 3 months after intervention. Liking increased more in the three intervention conditions than in the control condition, and there were no significant differences between the intervention conditions. These effects were maintained at follow-up. Children in both reward conditions increased consumption, and these effects were maintained for 3 months; however, the effects of exposure with no reward became nonsignificant by 3 months. These results indicate that external rewards do not necessarily produce negative effects and may be useful in promoting healthful eating.