Comparing estimates of physical activity in children across different cut-points and the associations with weight status

This study aimed to compare sedentary time (SED) and intensity-specific physical activity (PA) estimates and the associations of SED and PA with body mass index (BMI) and waist circumference (WC) using three different sets of cut-points in preschool-aged children. A total of 751 children (4.7 +/- 0.9 years, boys 52.7%) wore an ActiGraph GT3X+BT accelerometer on their hip for 7 days (24 h). Euclidean norm -1 G with negative values rounded to zero (ENMO) and activity counts from vertical axis (VACounts) and vector magnitude (VMCounts) were derived. Estimates of SED and light, moderate, vigorous, and moderate-to-vigorous PA (MVPA) were calculated for commonly used cut-points by Hildebrand et al., Butte et al., and Evenson et al. Furthermore, the prevalence of meeting the PA recommendation, 180 min/day of which at least 60 min/day being MVPA, were assessed for the cut-points. Multilevel mixed analysis was used to examine associations of SED and PA with BMI and WC. In accordance with the results, SED and PA intensity estimates differed largely across cut-points (i.e., SED = 22-341 min/day; light PA = 52-257 min/day; moderate PA = 5-18 min/day; vigorous PA = 7-17 min/day; MVPA = 13-35 min/day), and the prevalence of children meeting the PA recommendation varied from 4% to 70%. Associations of SED and PA with BMI or WC varied between the cut-points. Our results indicate that SED and PA estimates in preschool-aged children between studies using these cut-points are poorly comparable. Methods facilitating accelerometer-derived PA estimate comparison between studies are highly warranted.Peer reviewe

Relationship between screen time and sleep among Finnish preschool children : results from the DAGIS study

Study objectives: To examine the associations between screen time, the time spent on different screen devices, and sleep in a sample of Finnish preschool children. Methods: The current study analyzed cross-sectional data from the DAGIS study carried out in Finland in 2015-2016 on 736 children aged 3-6 years. Parents reported in a 7-day diary the durations the child used screen devices daily, with separate details about watching TV or DVDs, using tablets or smartphones, and using computers. In addition, parents reported children's bedtimes and wake-up times, which were further used in calculating sleep duration. Parents answered questions regarding their child's sleep consistency. Statistical analyses included adjusted general linear modeling. Results: An hourly increase in total screen time was associated with 11 min later bedtime (p <0.001) and 10 min shorter sleep duration (p <0.001). More TV/DVD watching was associated with later bedtimes (p = 0.016) and a shorter sleep duration (p = 0.001). More smartphone/tablet use was associated with later bedtimes (p = 0.005), later wake-up times (p = 0.038), and weaker sleep consistency (p = 0.024). More computer use was associated with later bedtimes (p = 0.046). Results did not differ between genders. Conclusions: Increased screen time was associated with later bedtimes and shorter sleep duration among preschool children. Adverse associations with sleep outcomes were found for each screen device. Attention should be paid to promoting balanced use of screens and regular sleep habits in young children.Peer reviewe

Accelerometer-Measured Physical Activity and Sedentary Time Differ According to Education Level in Young Adults

This study examined the association of education level with objectively measured physical activity and sedentary time in young adults. Data from the Finnish ESTER study (20092011) (n = 538) was used to examine the association between educational attainment and different subcomponents of physical activity and sedentary time measured using hip-worn accelerometers (ActiGraph GT1M) for seven consecutive days. Overall physical activity, moderate-to-vigorous physical activity (MVPA), light-intensity physical activity and sedentary time were calculated separately for weekdays and weekend days. A latent profile analysis was conducted to identify the different profiles of sedentary time and the subcomponents of physical activity. The educational differences in accelerometer-measured physical activity and sedentary time varied according to the subcomponents of physical activity, and between weekdays and weekend days. A high education level was associated with high MVPA during weekdays and weekend days in both sexes, high sedentary time during weekdays in both sexes, and a low amount of light-intensity physical activity during weekdays in males and during weekdays and weekend days in females. The results indicate different challenges related to unhealthy behaviours in young adults with low and high education: low education is associated with a lack of MVPA, whereas high education is associated with a lack of light-intensity physical activity and high sedentary time especially during weekdays.Peer reviewe

Longitudinal associations of movement behaviours with body composition and physical fitness from 4 to 9 years of age: structural equation and mediation analysis with compositional data

Background The associations of movement behaviours (physical activity [PA], sedentary behaviour [SB], and sleep) with body composition and physical fitness from pre-school to childhood, as well as the direction of the associations, could provide important information for healthy lifestyle promotion in children. This study investigated the longitudinal and bidirectional associations of movement behaviours with body composition and physical fitness measured at 4 and 9 years of age. Methods This longitudinal study included baseline (n = 315, 4.5 [SD = 0.1] years) and follow-up data (n = 231, 9.6 [SD = 0.1] years) from the MINISTOP study. Movement behaviours were measured for 7 days using wrist-worn accelerometers, body composition with air-displacement plethysmography, and physical fitness with the ALPHA health-related fitness test battery. Cross-lagged panel models and mediation analyses were performed in combination with compositional data analysis. Results We did not observe direct associations of the movement behaviours at 4 years with either body composition or physical fitness at 9 years (all P &amp;gt; 0.05). However, fat mass index at 4 years was negatively associated with vigorous PA (VPA), relative to remaining behaviours (VPA, beta = - 0.22, P = 0.002) and light PA (LPA), relative to SB and sleep (beta = - 0.19, P = 0.016) at 9 years. VPA (relative to remaining), moderate PA (MPA) (relative to LPA, SB, and sleep), and SB (relative to sleep) tracked from 4 to 9 years (all beta &amp;gt;= 0.17, all P &amp;lt; 0.002), and these behaviours shared variance with fat mass index (all|beta| &amp;gt;= 0.19, all P &amp;lt; 0.019), and aerobic, motor, and muscular fitness (all|beta| &amp;gt;= 0.19, all P &amp;lt; 0.014) at 9 years. Mediation analysis suggested that the tracking of VPA (relative to remaining behaviours) from 4 to 9 years was negatively associated with fat mass index (beta &amp;gt;= - 0.45, P = 0.012), and positively with aerobic fitness at 9 years (beta &amp;gt;= 1.64, P = 0.016). Conclusion PA and SB tracked from the pre-school years into childhood. Fat mass index at 4 years of age was negatively associated with VPA (relative to remaining behaviours) and LPA (relative to SB and sleep) at 9 years of age. The tracking of VPA was associated with lower fat mass index and higher aerobic fitness at 9 years of age. These findings suggest that higher levels of VPA in pre-school age, if maintained throughout childhood, may support the development of healthy body composition and aerobic fitness levels in later childhood.Funding Agencies|Karolinska Institute; Swedish Research Council [2012-2883]; Swedish Research Council for Health, Working Life and Welfare [2012-0906, 2021-00036]; Bo and Vera Axson Johnsons Foundation; Karolinska Institutet; Joanna Cocozza Foundation; Australian National Health and Medical Research Council (NHMRC) Early Career Fellowship [APP1162166]</p

Food and nutrient intakes in young adults born preterm

Background Adults born preterm have higher levels of cardiometabolic risk factors than their term-born peers. Studies have suggested that at least those born smallest eat less healthily. We examined the association between early (<34 weeks) and late (34 to 36 weeks) preterm birth and diet and food preferences in adult age. Methods Participants of two cohort studies located in Finland completed a validated food frequency questionnaire(FFQ) at age 24y to assess their usual diet and the adherence to healthy eating guidelines by using a recommended diet index(RDI).182 were born early preterm, 352 late preterm and 631 were term born controls. Results Young women born early preterm scored 0.77 points (95% CI 0.03, 1.51) lower in RDI when adjusted for sex, age, parental education and early life confounders, indicating a lower quality of diet. There were no differences between young women born late preterm and controls or among men. When food groups were assessed separately, men born early preterm had lower consumption of fruits and berries than controls. Conclusions Young women born early preterm have poorer adherence to healthy eating guidelines than their peers born at term. Differences in diet may contribute to increased cardiometabolic risk among adults born early preterm