Percorrer por autor "Malina, Robert M."
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- Body mass index and motor coordination: Non-linear relationships in children 6–10 yearsPublication . Lopes, Vitor P.; Malina, Robert M.; Maia, José A.R.; Rodrigues, Luis PauloBackground: Given the concern for health-related consequences of an elevated body mass index (BMI; obesity), the potential consequences of a low BMI in children are often overlooked. The purpose was to evaluate the relationship between the BMI across its entire spectrum and motor coordination (MC) in children 6–10 years. Methods: Height, weight, and MC (Körperkoordinationstest für Kinder, KTK test battery) were measured in 1,912 boys and 1,826 girls of 6–10 years of age. BMI (kg/m2) was calculated. KTK scores for each of the four tests were also converted to a motor quotient (MQ). One-way ANOVA was used to test differences in the BMI, individual test items, and MQ among boys and girls within age groups. Sex-specific quadratic regressions of individual KTK items and the MQ on the BMI were calculated. Girls and boys were also classified into four weight status groups using International Obesity Task Force criteria: thin, normal, overweight, and obese. Differences in specific test items and MQ between weight status groups were evaluated by age group in each sex. Results: Thirty-one percent of the sample was overweight or obese, whereas 5% was thin. On average, normal weight children had the highest MQ in both sexes across the age range with few exceptions. Overweight/obese children had a lower MQ than normal weight and thin children. The quadratic regression lines generally presented an inverted parabolic relationship between the BMI and MC and suggested a decrease in MC with an increase in the BMI. Conclusion: In general, BMI shows a curvilinear, inverted parabolic relationship with MC in children 6–10 years.
- Body mass index and physical fitness in Brazilian adolescentsPublication . Lopes, Vitor P.; Malina, Robert M.; Gomez-Campos, Rossana; Cossio-Bolaños, Marco; Arruda, Miguel de; Hobold, EdilsonEvaluate the relationship between body mass index and physical fitness in a cross-sectional sample of Brazilian youth.Methods: Participants were 3849 adolescents (2027 girls) aged 10-17 years. Weight and heightwere measured; body mass index was calculated. Physical fitness was evaluated with a multi-stage 20 m shuttle run (cardiovascular endurance), standing long jump (power), and push-ups(upper body strength). Participants were grouped by sex into four age groups: 10-11, 12-13,14 years. Sex-specific ANOVA was used to evaluate differences in each physicalQ2fitness item among weight status categories by age group. Relationships between body massindex and each physical fitness item were evaluated with quadratic regression models by agegroup within each sex.Results: The PF of thin and normal youth was, with few exceptions, significantly better thanthe physical fitness of overweight and obese youth in each age group by sex. On the other hand,physical fitness performances did not consistently differ, on average, between thin and normalweight and between overweight and obese youths. Results of the quadratic regressions indicateda curvilinear (parabolic) relationship between body mass index and each physical fitness itemin most age groups. Better performances were attained by adolescents in the mid-range of thebody mass index distribution, while performances of youth at the low and high ends of the bodymass index distribution were lower.
- Motor coordination as predictor of physical activity in childhoodPublication . Lopes, Vitor P.; Rodrigues, Luis Paulo; Maia, José A.R.; Malina, Robert M.This study considers relationships among motor coordination (MC), physical fitness (PF) and physical activity (PA) in children followed longitudinally from 6 to 10 years. It is hypothesized that MC is a significant and primary predictor of PA in children. Subjects were 142 girls and 143 boys. Height, weight and skinfolds; PA (Godin–Shephard questionnaire); MC (Körperkoordination Test für Kinder); and PF (five fitness items) were measured. Hierarchical linear modeling with MC and PF as predictors of PA was used. The retained model indicated that PA at baseline differed significantly between boys (48.3 MET/week) and girls (40.0 MET/week). The interaction of MC and 1 mile run/walk had a positive influence on level of PA. The general trend for a decrease in PA level across years was attenuated or amplified depending on initial level of MC. The estimated rate of decline in PA was negligible for children with higher levels of MC at 6 years, but was augmented by 2.58 and 2.47 units each year, respectively, for children with low and average levels of initial MC. In conclusion MC is an important predictor of PA in children 6–10 years of age.
- Motor coordination, activity, and fitness at 6 years of age relative to activity and fitness at 10 years of agePublication . Souza, Michele Caroline de; Chaves, Raquel; Lopes, Vitor P.; Malina, Robert M.; Silva, Rui Garganta; Seabra, André; Maia, José A.R.Health benefits of physical activity (PA) and physical fitness (PF) are reasonably well established, but tracking studies of PA and PF in childhood have not ordinarily considered the role of motor coordination. Objectives: To compare the growth status, gross motor coordination (GMC), PA and PF characteristics of children at 6 years of age relative to aerobic fitness (fit, unfit) and PA (active, sedentary) at 10 years. Methods: 285 primary school children (142 girls, 143 boys) resident on the four main Azorean islands, Portugal, were measured annually (in the Fall) from 6 to 10 years. ANOVA and t-tests were computed with SPSS 17.
- Motor coordination, physical activity and fitness as predictors of longitudinal change in adiposity during childhoodPublication . Lopes, Vitor P.; Maia, José A.R.; Rodrigues, Luis Paulo; Malina, Robert M.The purpose of this study was to examine the influence of motor coordination (MC), physical fitness (PF) and physical activity (PA) on the development of subcutaneous adiposity in a sample of children followed longitudinally from 6 to 10 years of age. Participants were 142 girls and 143 boys. Height, weight, and the triceps and subscapular skinfolds were measured annually between the ages of 6 and 10 years. PA was estimated with the Godin–Shephard questionnaire. MC was evaluated with the Körperkoordination Test für Kinder (KTK) test battery, and PF was assessed with four Fitnessgram tests: curl-ups (CU), push-ups (PU), trunk-lifts (TL) and one mile run/walk (MRW). Hierarchical linear modelling with MC, PF items and PA as predictors of the sum of two skinfolds (SKF) was used. The results showed that boys and girls differed significantly in SKF at baseline (girls: 19.7 mm; boys: 16.6 mm). Three PF items (CU, PU and MRW) and MC had a positive influence on SKF. For each unit improvement in CU, PU, MRW and MC, SKF was reduced by 0.06, 0.04, 0.06 and 0.12 mm, respectively. In conclusion, motor coordination, muscular strength and endurance, and aerobic endurance attenuated the accumulation of subcutaneous adipose tissue during childhood.
- Non-linear relationships between the BMI and physical fitness in Polish adolescentsPublication . Kwieciński, Janusz; Konarski, Jan M.; Strzelczyk, Ryszard; Krzykała, Magdalena; Konarska, Agata; Bartkowiak, Sylwia; Lopes, Vitor P.; Malina, Robert M.Comparisons of physical fitness in normal weight and overweight/obese youth generally highlight the negative consequences of an elevated BMI. In contrast, several studies of children and adolescents highlight the importance of variation in indicators of physical fitness across the full spectrum of BMIs from low through high.
- Physical Activity Patterns During School Recess: A Study in Children 6 to 10 Years OldPublication . Lopes, Vitor P.; Vasques, Catarina; Pereira, Beatriz; Maia, José A.R.; Malina, Robert M.The aims of this study were to characterize the spontaneous physical activity of children during school recess, and to estimate variation in physical activity associated with gender and age. A MTI actigraph (Model 7164) was used with a sample of 140 boys and 131 girls, 6 to 10 years of age. MTI counts were converted to METs using a regression equation developed for children. The number and average duration of periods of activity by intensity were calculated for each child during a 30 minute recess: rest or mild physical activity (≤ 2.9 METs), moderate physical activity (3.0-5.9 METs,), vigorous physical activity (6.0-8.9 METs) and very vigorous physical activity (≥ 9.0 METs). Boys and girls spent about 50% of the recess in physical activity. Physical activity was characteristically done in very short bursts with intervals of rest or mild physical activity. The number of episodes of physical activity of all intensity levels was lower in older children while the inverse occurred at rest or mild physical activity. Boys engaged in higher intensity activity than girls and in general spent more recess time in physical activity.
- Testing the motor proficiency barrier hypothesis for physical activity and weight status in youthPublication . Lopes, Vitor P.; Malina, Robert M.; Lopes, L.; Santos, Rute; Stodden, David F.; Rodrigues, Luis PauloThe purpose was to evaluate the implications of a proficiency barrier (PB) for physical activity (PA), sedentary time (ST) and weight status (WS) in a two-stage study. In Stage 1, motor quotient (MQ) cut-off values, based on the KTK test, for differentiating overweight/obese from normal weight, and sedentary from non-sedentary were identified in a sample of 734 children (353 girls) of 10 years of age. In Stage 2, the cut-off values were used to define low and high (respectively below and above the PB) MQ groups among 217 youth (118 girls) of 12.9(0.4) years of age. WS, PA and ST in the two MQ groups were compared at baseline and 1.5 years later. Chi-square tests were used to test the independence of low and high MQ classification on MS, moderate-to-vigorous PA, and sedentary time. Odds of being overweight/obese and sedentary according to MQ status at baseline were calculated. MQ of 79 for girls and 75 for boys were defined as the PB. In girls, the PB predicted significantly different classifications of WS, and a combination of WS and moderate-to-vigorous PA. In boys, the PB predicted significantly different classifications based on combined WS and moderate-to-vigorous PA at baseline. Having a MQ below the PB was associated with a 2.78 higher probability of being overweight/obese. In conclusion, the results suggest that a PB that influences PA and WS among youth may exist.
- Variation in physical activity, fitness and motor competence according to weight status of 12-15 years youngsters from Cabo VerdePublication . Lopes, Otniel J.P.B; Malina, Robert M.; Lopes, Vitor P.Aim: evaluate physical activity (PA), physical fitness (PF) and motor competence (MC) relative weight status among Cabo Verde youth. Height and weight were measured in 343 boys and girls 12-14 years. PF tests included grip strength, push-ups, curl-ups, sit-and-reach, one-mile-run/walk. KTK tests were the indicator of MC. PA was estimated with pedometers. ANCOVA was used. PA and MC did not vary consistently with weight status. Cardiorespiratory fitness and grip strength per unit mass of thin girls was significantly better than normal weight and overweight/obese girls. Underweight boys performed significantly better in grip strength per unit mass than normal and overweight/obese boys. In conclusions, differences among youth by weight status were not apparent except for the one-mile run in girls and grip strength per unit body mass in both sexes. MC differed by weight status only among girls
- Weight status, BMI and physical fitness in polish youth: relationships between 1986 and 2016Publication . Bartkowiak, Sylwia; Konarski, Jan M.; Strzelczyk, Ryszard; Janowski, Jarosław; Karpowicz, Małgorzata; Lopes, Vitor P.; Malina, Robert M.One of the components affecting the level of health is physical fitness and diets, which is also considered the foundation of a healthy lifestyle. Methods: Samples by survey ranged from 871 to 1,417 (boys) and from 843 to 1,326 (girls). Speed (5 m run), agility (figure-8-run), explosive power (vertical jump), flexibility (stand and reach) and cardiovascular fitness (step test) were measured. The Body Mass Index (BMI) of each student was classified as Thin, Normal weight or Overweight/Obese (Owt/Ob) relative to International Obesity Task Force (IOTF) criteria. Fitness items were compared among weight status groups and across surveys with sex-specific analyses of covariance. Regressions of each fitness item on the BMI in the four surveys were done using linear and nonlinear quadratic models. Results: Performances on all fitness tests except flexibility were poorer among Owt/Ob compared to Normal and Thin youth, but performances on fitness tests within weight status groups did not differ consistently across surveys. Conclusions: Relationships between the BMI and fitness tests varied across surveys, but suggested reasonably consistent curvilinear relationships between fitness tests and the BMI among boys more so than girls.