Neuroelectric indices of pre-motor planning and adiposity are selectively related to balance in children.

BACKGROUND: Motor function and weight status are components of physical fitness that have been implicated in childhood motor and cognitive development. The lateralized readiness potential (LRP), an index of motor planning and action, can provide context surrounding relationships between fitness and brain activity underlying cognitive and motor functions. This study evaluated the relationship between the LRP and motor skills, as well as associations between weight status and neural and behavioral motor functions. METHODS: Children aged 7-13 (n = 35) participated in a cross-sectional study, using the Movement Assessment Battery for Children 2nd edition (MABC-2) to assess balance, manual dexterity, and aiming/catching. The stimulus- (LRP-S) and response-locked (LRP-R) LRPs were elicited from a modified flanker task. Stepwise regressions tested the association between LRPs and MABC-2 components. Linear regressions were conducted to examine BMI and %Fat in relation to LRPs and MABC-2 components. RESULTS: Analyses revealed that LRP-S mean amplitude difference (ß = 0.401, P = 0.042) and reaction time interference scores (ß = 0.545, P = 0.004) were positively associated with balance, after adjusting for covariates. The LRP-S and interference scores did not predict other MABC-2 outcomes and LRP-R did not predict any MABC-2 components. Further, %Fat (ß = -0.439, P = 0.044), not BMI (ß = -0.364, P = 0.082), only predicted balance. CONCLUSION: We found that changes in the LRP-S amplitude were positively associated with balance, and %Fat was negatively related to balance. This evidence is that fitness components such as weight status and coordination are related to neural markers of motor function which may be useful in intervention designs aimed to improve brain function via improvements in physical fitness and health behaviors.

Macular Pigment Optical Density and Skin Carotenoids in a Childhood Sample.

BACKGROUND: Carotenoids are plant pigments with light filtering and antioxidant properties that deposit in human tissues, including retina and skin. Descriptive characteristics and covariates of carotenoid status in macula and skin have been examined in adults; however, similar studies in children are limited. Thus, this study aimed to delineate how factors of age, sex, race, weight status, and dietary carotenoid intake relate to macular and skin carotenoids in children. METHODS: Children (7-13 y, N = 375) completed heterochromatic flicker photometry to assess macular pigment optical density (MPOD). Participants underwent anthropometrics to measure weight status (BMI percentile [BMI%]), and parent/guardian provided demographic information. Subsample data were available for skin carotenoids (N = 181), assessed using reflection spectroscopy, and dietary carotenoids (N = 101) using the Block Food Frequency Questionnaire. Relationships between skin and macular carotenoids were assessed using partial Pearson's correlations controlling for age, sex, race, and BMI%. Relationships between dietary carotenoids and macular and skin carotenoids were assessed using stepwise linear regression including age, sex, race, and BMI% in the model. RESULTS: Mean MPOD was 0.56 ± 0.22 and skin carotenoid score was 282 ± 94.6. There was no significant correlation between MPOD and skin carotenoids (r = 0.02, P = 0.76). BMI% was negatively associated with skin (stdß = -0.42, P < 0.001), but not macular carotenoids (stdß = -0.04, P = 0.70). Neither MPOD nor skin carotenoids were associated with age, sex, or race (all P > 0.10). MPOD was positively associated with energy-adjusted reported lutein + zeaxanthin intake (stdß = 0.27, P = 0.01). Skin carotenoids were positively associated with energy-adjusted reported carotenoid intake (stdß = 0.26, P = 0.01). CONCLUSIONS: The mean MPOD values in children were higher than what has been reported in adult populations. Previous studies in adult samples report an average MPOD of 0.21. Although macular and skin carotenoids were not related, they were associated with dietary carotenoids relevant to the respective tissues; however, skin carotenoids may be more susceptible negative influence from higher weight status.