Resemblance in physical activity levels: The Portuguese sibling study on growth, fitness, lifestyle, and health

Correlations in Siblings' Physical Activity and Sedentary Behavior: Results from the Hispanic Community Children's Health Study/Study of Latino Youth

Background: Family is an important determinant of youth's health behaviors, yet research on the importance of intragenerational relationships for determining physical activity (PA) and sedentary behaviors (SBs) is limited. This study examined correlations in siblings' total PA, moderate-to-vigorous physical activity (MVPA), and SB and explored potential determinants of differences in Hispanic/Latino siblings' activity. Methods: Hispanic/Latino 8-16-year olds from the cross-sectional Hispanic Community Children's Health Study/Study of Latino Youth with ≥1 sibling enrolled were examined (n = 535). Activity was assessed using the Actical accelerometer. Linear mixed models were used with total PA, MVPA, or SB as the outcome; correlations among siblings' PA and SB were assessed with intraclass correlation coefficients (ICCs). Results: ICCs for siblings' total PA, MVPA, and SB were 0.26 (95% confidence interval: 0.16-0.36), 0.29 (0.21-0.38), and 0.42 (0.34-0.51), respectively. There were no differences in correlations between siblings who were all brothers compared to all sisters. However, compared to siblings of differing sexes, siblings who were all brothers had the strongest correlations in total PA (0.61 [0.46-0.76]) and MVPA (0.64 [0.49-0.78]), and siblings who were all sisters had the weakest correlations in SB (0.14 [-0.10 to 0.37]). Correlations did not differ according to age, and social and environmental measures did not explain differences in siblings' PA or SB. Conclusions: Correlations in Hispanic/Latino siblings' PA and SB ranged from slight to fair, with siblings who were all brothers generally having the strongest correlations. Future research should examine determinants of sex-specific differences in siblings' PA and SB correlations.

Sibling Resemblance in Physical Activity Levels: The Peruvian Sibling Study on Growth and Health

Physical activity is associated with a host of positive health outcomes and is shaped by both genetic and environmental factors. We aim to: (1) estimate sibling resemblance in two physical activity phenotypes [total number of steps∙day^-1 and minutes for moderate steps per day (min∙day^-1)]; and (2) investigate the joint associations of individual characteristics and shared natural environment with intra-pair sibling similarities in each phenotype. We sampled 247 biological siblings from 110 nuclear families, aged 6-17 years, from three Peruvian regions. Physical activity was measured using pedometers and body mass index was calculated. In general, non-significant variations in the intraclass correlation coefficients were found after adjustment for individual characteristics and geographical area for both phenotypes. Further, no significant differences were found between the three sib-ship types. Sister-sister pairs tended to take fewer steps than brother-brother (β = -2908.75 ± 954.31). Older siblings tended to walk fewer steps (β = -81.26 ± 19.83), whereas body mass index was not associated with physical activity. Siblings living at high-altitude and in the Amazon region had higher steps/day (β = 2508.92 ± 737.94; β = 2213.11 ± 776.63, respectively) compared with their peers living at sea-level. In general, we found no influence of sib-types, body mass index, and/or environment on the two physical activity phenotypes.

Body Weight Perception and Health-Related Behaviors Among U.S. Adolescents: Mediating Effects of Body Weight Control Behaviors

This study examined mediating effects of body weight control behaviors in the relationship between body weight perception and health-related behaviors among 11,458 U.S. adolescents from the 2010 National Youth Physical Activity and Nutrition Survey. Parallel multiple mediation analysis was performed for the secondary data analysis. Nearly one third of adolescents (32.5%) had overweight or obesity; one quarter (25.0%) perceived themselves as slightly overweight and 5.1% thought they were very overweight. More girls (58.6%) had tried to lose weight than boys (32.3%), while boys were more physically active than girls. Healthy and unhealthy weight control behaviors significantly mediated the relationship between adolescents' body weight perception and health-related behaviors (physical activity and screen time). Teachers and parents should help adolescents have accurate weight perception and utilize reliable and healthy weight control strategies. Future studies should consider the intercorrelated relationships among adolescents' perceptions and behaviors regarding weight to provide successful weight control intervention programs.

Familial Resemblance in Body Shape and Composition, Metabolic Syndrome, Physical Activity and Physical Fitness: A Summary of Research in Portuguese Families and Siblings

We report a summary of Portuguese families and siblings research under the umbrella of the Portuguese Healthy Family Project. Families lived in mainland Portugal, as well as in the Azores and Madeira islands. All samples comprise children and adolescents (9-20 years) and their parents (27-57 years). Recruitment procedures and phenotypes were detailed. Familial resemblance in body shape and composition, metabolic syndrome, physical fitness, physical activity and sedentary behaviors are presented, as well as future research avenues.

Sibling Similarity in Metabolic Syndrome: The Portuguese Sibling Study on Growth, Fitness, Lifestyle and Health

This study aims to estimate sibling resemblance in metabolic syndrome (MS) markers, and to investigate the associations of biological and behavioral characteristics with MS. The sample comprises 679 biological siblings (363 females; 316 males) aged 9-20 years. MS markers included waist circumference (WC), high-density lipoprotein cholesterol (HDL-C), triglycerides (TRI), fasting glucose (GLU) and systolic blood pressure (SBP). Body mass index (BMI), biological maturation, muscular, and cardiorespiratory fitness were also assessed. Behavioral characteristics, including dietary intake and physical activity, were self-reported by questionnaire. Multilevel models were used, and sibling resemblance was estimated using the intraclass correlation (ρ). In general, same-sex siblings showed higher resemblance in MS markers than opposite-sex siblings. However, variability in sibling resemblance in MS markers was evident with the inclusion of covariates. Biological characteristics including age, BMI and maturity offset influenced all MS markers except for TRI. Importantly, behavioral characteristics diversely influenced MS markers: fruit and vegetables only influenced SBP, whereas physical activity affected HDL-C. Additionally, muscular fitness impacted significantly on MS Z-score, WC, SBP and GLU, whilst cardiorespiratory fitness only affected WC. In conclusion, biological and behavioral characteristics influenced the expression of MS markers. These results confirmed the importance of considering individual characteristics when designing individualized programs for diminishing the adverse effects of specific MS markers.

Sibship, physical activity, and sedentary behavior: a longitudinal, observational study among Mexican-heritage sibling dyads

BACKGROUND

Shared genetic and environmental factors suggest that family relationships are important predictors of obesity-related behaviors, yet little is known about how siblings influence physical activity and sedentary behaviors. This study examined physical activity and sedentary behavior between sibling dyads across summer and fall time points and determined if birth order and gender modify the relationship between sibling behaviors.

METHODS

Mexican-heritage families residing in colonias along the United States-Mexico border were recruited using promotoras de salud to participate in summer and school year surveys. Eighty-seven sibling dyads had complete data for the physical activity sub-study: 21 older brother-younger brother, 21 older brother-younger sister, 23 older sister-younger brother, and 22 older sister-younger sister dyads. Physical activity and sedentary behavior were measured using a validated 7-day recall instrument to create summary measures of weekly active, moderate-to-vigorous physical activity (MVPA) metabolic equivalents (MET), sitting, and screen time minutes. We used linear regression analyses to examine changes over time and the association between older and younger sibling behavior.

RESULTS

During summer, older siblings (mean age = 11.2 years) reported 1069 active minutes and 1244 sitting minutes per week; younger siblings (mean age = 8.3 years) reported 1201 active minutes and 1368 sitting minutes per week. Younger brothers reported fewer active minutes (mean = - 459.6; p = 0.01) and fewer MVPA MET-minutes (mean = - 2261.7; p = 0.02) of physical activity during the fall. Within all 87 dyads, older sibling physical activity was significantly associated with younger sibling active minutes (B = 0.45;p = 0.004) and MET-minutes (B = 0.45;p = 0.003) during summer but not fall; older sibling sedentary behavior was significantly associated with younger sibling sitting (B = 0.23;p = 0.01) and screen time minutes (B = 0.23;p = 0.004) during fall but not summer. After stratifying by gender dyad groups, younger brother behavior was strongly associated with older brother behavior at both time points.

CONCLUSION

Younger siblings appear to emulate the physical activity behaviors of their older siblings during non-school summer months and sedentary behaviors of older siblings during school-time fall months, especially older brother-younger brother dyads. Family-based interventions to increase physical activity and decrease sedentary behavior are growing in popularity, but more work is needed to understand the role of sibling influences.

Profile Resemblance in Health-Related Markers: The Portuguese Sibling Study on Growth, Fitness, Lifestyle, and Health

The co-occurrence of health-related markers and their associations with individual, family, and environmental characteristics have not yet been widely explored in siblings. We aimed to identify multivariate profiles of health-related markers, analyze their associations with biological, sociodemographic, and built environment characteristics, and estimate sibling resemblance in these profiles. The sample includes 736 biological siblings aged 9–20 years. Body fat was measured with a portable bioelectrical impedance scale; biological maturation was assessed with the maturity offset; handgrip strength, standing long jump, one-mile run, and shuttle run were used to mark physical fitness. Health behaviors, sociodemographic, and built environmental characteristics were recorded by questionnaire. Latent profile analysis and multilevel logistic regression models were used; sibling resemblance was estimated with the intraclass correlation (ρ). Two multivariate profiles emerged: “P1 = fit, lower fat and poorer diet” (86.7%) and “P2 = higher fat and lower fit, but better diet” (13.3%). Siblings whose fathers were less qualified in their occupation were more likely to belong to P2 (OR = 1.24, p = 0.04); those whose fathers with Grade 12 and university level education were more likely to fit in P2 compared to peers living with fathers having an educational level below Grade 12 (OR = 3.18, p = 0.03, and OR = 6.40, p = 0.02, Grade 12 and university level, respectively). A moderate sibling profile resemblance was found (0.46 ≤ ρ ≤ 0.55). In conclusion, youth health-related markers present substantial differences linked with their body composition, physical fitness and unhealthy diet. Furthermore, only father socio-demographic characteristics were associated with profile membership. Sibling´s profile resemblance mirrors the effects of genetics and shared characteristics.

How Consistent are Genetic Factors in Explaining Leisure-Time Physical Activity and Sport Participation? The Portuguese Healthy Families Study

This study investigates how consistent genetic factors are, as measured by heritability estimates (h2), in the leisure-time physical activity index (LTPAI) and sport participation index (SPI) from early (10-14 yrs) to late adolescence (15-19 yrs). The sample comprises 12,385 subjects from 3,378 Portuguese nuclear families. Height and weight were measured and body mass index (BMI) was calculated, and the LTPAI and SPI were estimated by questionnaire. Socioeconomic status (SES) was assessed by parental occupation. Analyses were done using S.A.G.E. software. Our results showed that h2 estimates for the LTPAI and SPI in the two age groups (10-14 yrs and 15-19 yrs) were stable: for the LTPAI, h2 = 0.297 and 0.322, respectively; and for the SPI, h2 = 0.413 and 0.428, respectively. Sibling correlations and environmental correlations are higher in the younger age group for both the LTPAI and the SPI. Spousal correlations are higher in the younger age group for the LTPAI and lower for the SPI than the older group. Parent-offspring correlations are similar in both age groups for the LTPAI and SPI. In conclusion, the influence of genetic factors on physical activity and sport participation remains stable across age in adolescence. However, variation in sibling correlations - in particular, environmental correlations - was observed. These findings suggest that shared/non-shared environmental factors express different degrees of importance across age. Future intervention programs aiming to promote change in behaviors need to consider these results to bring about positive changes in physical activity and sport participation behaviors within the family setting.