Physical fitness and white matter microstructure in children with overweight or obesity: the ActiveBrains project.

Recent studies investigated the association of cardiorespiratory fitness with white matter microstructure in children, yet little work has explored to what extent other components of physical fitness (i.e., muscular or motor fitness) are associated with white matter microstructure. Indeed, this association has not been previously explored in children with overweight/obesity who present a different white matter development. Therefore, we aimed to examine associations between physical fitness components and white matter microstructure in children with overweight/obesity. In total, 104 (10.04 ± 1.15 years old; 43 girls) children were included in this cross-sectional study. Physical fitness was assessed using the ALPHA-fitness test battery. Fractional anisotropy (FA) and mean diffusivity were derived from diffusion tensor imaging (DTI). No association was found between physical fitness and global DTI metrics (all P > 0.082). Within individual tracts, all associations became non-significant when analyses were adjusted for multiple comparisons. Using the voxel-wise approach, we identified a small cluster in the left lateral frontal lobe where children with greater upper-body muscular fitness showed higher FA (PFWE-corrected = 0.042). Although our results cannot conclude physical fitness is related to white matter microstructure in children with overweight/obesity; those findings indicate that the association of muscular fitness with white matter microstructure might be more focal on frontal areas of the brain, as opposed to global differences.

Inflammation in metabolically healthy and metabolically abnormal adolescents: The HELENA study.

BACKGROUND AND AIMS: Inflammation may influence the cardio-metabolic profile which relates with the risk of chronic diseases. This study aimed to assess the inflammatory status by metabolic health (MH)/body mass index (BMI) category and to assess how inflammatory markers can predict the cardio-metabolic profile in European adolescents, considering BMI. METHODS AND RESULTS: A total of 659 adolescents (295 boys) from a cross-sectional European study were included. Adolescents were classified by metabolic health based on age- and sex-specific cut-off points for glucose, blood pressure, triglycerides, high density cholesterol and BMI. C-reactive protein (CRP), tumor necrosis factor alpha (TNF-α), interleukin (IL-6), complement factors (C3, C4) and cell adhesion molecules were assessed. RESULTS: Metabolically abnormal (MA) adolescents had higher values of C3 (p < 0.001) and C4 (p = 0.032) compared to those metabolically healthy (MHy). C3 concentrations significantly increased with the deterioration of the metabolic health and BMI (p < 0.001). Adolescents with higher values of CRP had higher probability of being in the overweight/obese-MH group than those allocated in other categories. Finally, high C3 and C4 concentrations increased the probability of having an unfavorable metabolic/BMI status. CONCLUSIONS: Metabolic/BMI status and inflammatory biomarkers are associated, being the CRP, C3 and C4 the most related inflammatory markers with this condition. C3 and C4 were associated with the cardio-metabolic health consistently.

Physical fitness and psychological health in overweight/obese children: A cross-sectional study from the ActiveBrains project.

OBJECTIVES: To examine the associations of physical fitness (i.e. cardiorespiratory fitness, muscular strength, and speed/agility) with psychological distress and psychological well-being in overweight/obese pre-adolescent children. DESIGN: 110 overweight/obese children (10.0±1.1years old, 61 boys) from the ActiveBrains project (http://profith.ugr.es/activebrains) participated in this cross-sectional study. METHODS: Physical fitness was evaluated by the ALPHA battery test. Cardiorespiratory fitness was additionally evaluated by a maximal incremental treadmill. Stress was assessed by the Children's Daily Stress Inventory, anxiety by the State-Trait Anxiety Inventory, depression by the Children Depression Inventory, positive affect and negative affect by the Positive and Negative Affect Scale for Children, happiness by the Subjective Happiness Scale, optimism by the Life Orientation Test, and self-esteem by the Rosenberg Self-Esteem questionnaire. Linear regression adjusted for sex and peak height velocity was used to examine associations. RESULTS: Absolute upper-body muscular strength was negatively associated with stress and negative affect (ß=-0.246, p=0.047; ß=-0.329, p=0.010, respectively). Furthermore, absolute lower-body muscular strength was negatively associated with negative affect (ß=-0.301, p=0.029). Cardiorespiratory fitness, expressed by the last completed lap, and relative upper-body muscular strength were positively associated with optimism (ß=0.220, p=0.042; ß=0.240, p=0.017, respectively). Finally, absolute upper-body muscular strength was positively associated with self-esteem (ß=0.362, p=0.003) independently of sex and weight status (p for interactions >0.3), and absolute lower-body muscular strength was also positively associated with self-esteem (ß=0.352, p=0.008). CONCLUSIONS: Muscular strength was associated with psychological distress (i.e. stress and negative affect) and psychological well-being (i.e. optimism and self-esteem) as well as cardiorespiratory fitness was associated with optimism. Therefore, increased levels of physical fitness, specifically muscular strength, could have significant benefits for overweight/obese children psychological health.

Parental body mass index and its association with body composition, physical fitness and lifestyle factors in their 4-year-old children: results from the MINISTOP trial.

BACKGROUND/OBJECTIVES: To examine the association between parental body mass index (BMI) and their offspring's body composition, physical fitness and lifestyle factors (that is, sedentary time, physical activity and diet). SUBJECTS/METHODS: A total of 307 preschoolers (4.5±0.1 years) and their parents (fathers: 38.1±5.1 years and mothers: 35.6±4.2 years) participated in this study. Parental BMI was calculated using self-reported weight and height. Preschoolers body composition was assessed using: BMI, fat mass percentage, fat mass index, fat-free mass index (measured via air-displacement plethysmography) and waist circumference. Physical fitness was assessed by the PREFIT fitness battery. Lifestyle factors were assessed using the ActiGraph wGT3x-BT (sedentary time and physical activity), and the mobile-phone based tool for energy balance in children (diet). RESULTS: Parental BMI were positively associated with their offspring's BMI (paternal BMI: standardised beta, ß=0.233, P<0.001; maternal BMI: ß=0.186, P=0.001), fat mass index (paternal BMI: ß=0.130, P=0.026; maternal BMI: ß=0.163, P=0.005), fat-free mass index (paternal BMI: ß=0.214, P<0.001; maternal BMI: ß=0.119, P=0.036) and waist circumference (paternal BMI: ß=0.178, P=0.001; maternal BMI: ß=0.179, P=0.001). A negative association was found between maternal BMI and their offspring's standing long jump test (ß=-0.132, P=0.022). Paternal BMI was associated with their offspring's sedentary time (ß=0.100, P=0.026), whereas parental BMI was not associated with neither physical activity nor diet (all P⩾0.104). CONCLUSIONS: Parental BMI was positively associated with their offspring's BMI, fat as well as fat-free mass index and waist circumference. Moreover, a higher paternal and maternal BMI were related to higher levels of sedentary time and a lower performance in the standing long jump test of their offspring, respectively.

Physical activity intensity, sedentary behavior, body composition and physical fitness in 4-year-old children: results from the ministop trial.

BACKGROUND: Existing knowledge on associations of physical activity (PA) and sedentary behavior (SB) with body composition and physical fitness in preschoolers is limited. OBJECTIVE: To examine associations of PA and SB with body composition and physical fitness in healthy Swedish 4-year-old children. METHODS: We utilized baseline data collected in 2014 for the population-based MINISTOP trial (n=307). Light-intensity PA (LPA), moderate-intensity PA (MPA), vigorous-intensity PA (VPA), moderate-to-vigorous PA (MVPA) and SB were measured using accelerometry (ActiGraph-wGT3x-BT). Body composition was measured using air-displacement plethysmography, and physical fitness (that is, cardiorespiratory fitness, lower and upper body muscular strength and motor fitness) was measured using the PREFIT fitness test battery. Multiple linear regression models adjusted for relevant confounders, and in addition, isotemporal substitution models were applied. RESULTS: Greater MVPA was associated with lower fat mass percent (%FM, P=0.015), and greater VPA and MVPA were associated with higher fat-free mass index (FFMI, P=0.002 and P=0.011). In addition, greater VPA and MVPA were associated with higher scores for all physical fitness tests (P=0.042 to P<0.001). The results for MVPA were primarily due to VPA. SB was associated with weaker handgrip strength (P=0.031) when PA was not adjusted, but after adjusting also for VPA, the significant association disappeared (P=0.25). Substituting 5 min per day of SB, LPA or MPA with 5 min per day of VPA was associated with higher FFMI and better scores for cardiorespiratory fitness and motor fitness. Correspondingly, substituting 5 min per day of VPA with SB or LPA was associated with weaker performance for lower muscular strength. CONCLUSIONS: Time spent on VPA was associated with higher FFMI and better physical fitness. The results suggest that promoting VPA may be important to improve childhood body composition and physical fitness already at an early age.

Prevalence of overweight/obesity and fitness level in preschool children from the north compared with the south of Europe: an exploration with two countries.

BACKGROUND: North-south differences in the prevalence of obesity and fitness levels have been found in European adolescents, yet it is unknown if such differences already exist in very young children. OBJECTIVES: This study aims to compare the prevalence of overweight/obesity and fitness levels in preschool children aged 4 years from Sweden (north of Europe) and Spain (south of Europe). METHODS: The sample consisted of 315 Swedish and 128 Spanish preschoolers. Anthropometry (weight, height, waist circumference) and fitness (strength, speed-agility, balance and cardiorespiratory fitness) were assessed. Analysis of covariance adjusted for age, sex and height/body mass index (BMI) was used. RESULTS: Preschool children from Sweden had lower prevalence of overweight/obesity than their peers from Spain (World Obesity Federation, mean difference, MD = -9%, P = 0.010; World Health Organization, MD = -11%, P = 0.011). Concerning fitness, preschoolers from Spain were more fit in terms of upper-muscular strength (MD = +0.4 kg, P = 0.010), speed-agility (MD = -1.9 s, P = 0.001), balance (MD = +4.0 s, P = 0.001) and cardiorespiratory fitness (MD = boys = +6.6 laps, girls = +2.3 laps; P < 0.001 for all), yet they had worse lower-muscular strength (MD = -7.1, P ≤ 0.001) than those from Sweden. Differences in upper-muscular strength were largely explained by differences in BMI, and differences in cardiorespiratory fitness should be interpreted cautiously due to some methodological deviations. CONCLUSIONS: These findings suggest that a higher prevalence of overweight/obesity in Spain compared with Sweden is present already at early childhood, while differences in physical fitness components showed mixed findings.

Health-related physical fitness is associated with total and central body fat in preschool children aged 3 to 5 years.

OBJECTIVES: To investigate whether health-related physical fitness is associated with total and central body fat in preschool children. METHODS: A total of 403 Spanish children aged 3-5 years (57.8% boys) participated in the study. Health-related physical fitness was measured by the PREFIT battery: the handgrip strength and the standing long-jump tests (muscular strength), the 4 × 10 m shuttle run (speed-agility), the one-leg stance tests (balance) and the PREFIT-20 m shuttle run test (cardiorespiratory fitness). Body mass index and waist circumference were used as markers of total and central body fat, respectively. RESULTS: There were significant associations between all health-related physical fitness tests and body mass index (ß = 0.280 ± 0.054, ß = -0.020 ± 0.006, ß = 0.154 ± 0.065 and ß = -0.034 ± 0.011 for the handgrip strength, standing long jump, 4 × 10 m shuttle run and PREFIT-20 m shuttle run tests, respectively, all P ≤ 0.019) after adjusting for sex and age. Similarly, there was significant associations of standing long jump (ß = -0.072 ± 0.014), 4 × 10 m shuttle run (ß = 0.652 ± 0.150) and PREFIT-20 m shuttle run tests (ß = -0.102 ± 0.025) with waist circumference (all P ≤ 0.001), except for handgrip strength (ß = 0.254 ± 0.145, P = 0.081) and one-leg stance (ß = -0.012 ± 0.009, P = 0.156). CONCLUSIONS: The present study extends previous findings in older youth. Fitness assessment should be introduced in future epidemiological and intervention studies in preschool children because it seems to be an important factor determining health.

Assessment of handgrip strength in preschool children aged 3 to 5 years.

We investigated whether there is an optimal grip span for determining the maximum handgrip strength in preschool children and if it is influenced by gender, age, or hand size. A total of 292 preschool children (3-5 years; 59.2% boys) carried out the handgrip strength test with different grip spans (4.0, 4.5, 5.0, 5.5, and 6.0 cm). The hand size was also measured. We also determined the reliability of the optimal grip span in another group of children (n = 56, 57% boys) who did the test twice, with a 3-hour difference between tests. The results showed that 4.0 cm is the optimal grip span to determine the maximum handgrip strength in preschool children. This result applied to both genders, all age groups, and hand sizes. Paired t-tests showed no significant differences between test and retest. These findings may guide clinicians and researchers in selecting the optimal grip span when measuring handgrip strength in preschool children.Level IV.