J. R. Ruiz

Interrater reliability and time measurement validity of speed-agility field tests in adolescents

Vicente-Rodríguez, G, Rey-López, JP, Ruíz, JR, Jiménez-Pavón, D, Bergman, P, Ciarapica, D, Heredia, JM, Molnar, D, Gutierrez, A, Moreno, LA, and Ortega, FB. Interrater reliability and time measurement validity of speed-agility field tests in adolescents. J Strength Cond Res 25(7): 2059-2063, 2011—The aim of this study was to examine the interrater reliability (trained vs. untrained raters) and criterion-related validity (manual vs. automatic timing) of the 4 × 10-m shuttle run and 30-m running speed tests (times measured). The study comprised 85 adolescents (38 girls) aged 13.0-16.9 years from the Healthy Lifestyle in Europe by Nutrition in Adolescence study. The time required to complete the 4 × 10-m shuttle run and 30-m running tests was simultaneously measured (a) manually with a stopwatch by both trained and untrained raters (for interrater reliability analysis), and (b) by using photoelectric cells (for validity analysis). Systematic error, random error, and heteroscedasticity were studied with repeated-measured analysis of variance and Bland-Altman plots. The systematic error for untrained vs. trained raters and the untrained raters vs. photoelectric cells were in all cases ∼0.1 seconds (p < 0.01), that is, untrained raters recorded higher times. No systematic error was found between trained raters and photoelectric cells (p > 0.05). No heteroscedasticity was shown in any case (p > 0.05). The findings indicate that manual measurements by a trained rater, using a stopwatch, seem to be a valid method to assess speed and agility fitness testing in adolescents. Researchers must be trained to minimize the measurement error.

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

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.

The effect of a multidisciplinary intervention program on hepatic adiposity in overweight-obese children: protocol of the EFIGRO study.

BACKGROUND Non-alcoholic fatty liver disease is the most frequent liver abnormality observed in overweight or obese children and is strongly associated with metabolic syndrome and insulin resistance. OBJECTIVES (i) To evaluate the effect of a 22-week multidisciplinary intervention program on hepatic fat fraction in overweight or obese children and (ii) to examine the effect of the intervention on cardiometabolic risk factors, self-esteem and well-being. METHODS A total of 160 children, 9-11 years, will be recruited by pediatricians and randomly assigned to control (N = 80) or intervention (N = 80) groups. The control group will receive a family-based lifestyle and psycho-educational program (2 days/month), while the intervention group will attend the same lifestyle education and psycho-educational program plus the exercise program (3 days/week). The duration of training sessions will be 90 min of exercise, including warm-up, moderate to vigorous aerobic activities, and strength exercises. The primary outcome is the change in hepatic fat fraction (magnetic resonance imaging, MRI). Secondary outcomes include cardiometabolic risk factors such as total adiposity (dual Xray absorptiometry), visceral adiposity (MRI), functional peak aerobic capacity (cardiopulmonary exercise testing), blood pressure, muscular fitness, speed–agility, and fasting blood insulin, glucose, C-reactive protein, alanine aminotransferase, aspartate aminotransferase, gamma glutamyltransferase, lipid profile and psychological measurements (questionnaires). All the measurements will be evaluated at baseline prior to randomization and after the intervention. DISCUSSION This study will provide insight in the efficacy of a multidisciplinary intervention program including healthy lifestyle education, psycho-education and supervised exercise to reduce hepatic fat and cardiometabolic risk in overweight children.

Impact of the choice of threshold on physical activity patterns in free living conditions among adolescents measured using a uniaxial accelerometer: The HELENA study

Abstract The aim of this study was to assess the impact of the choice of threshold on physical activity patterns measured in adolescents under free living conditions (FLC) using a uniaxial accelerometer. The study comprised 2043 adolescents (12.5–17.5 years) participating in the HELENA Study. Participants wore a uniaxial accelerometer for 7 days. The PA patterns were assessed using thresholds determined from six different studies. For each of the thresholds used, the number of adolescents fulfilling the recommendation of 60 min of moderate to vigorous PA (MVPA) per day was also calculated. A significant difference was found between thresholds regardless of the activity level: differences of 38%, 207%, 136%, and 2780% for sedentary, light, moderate, and vigorous intensity PA, respectively (P < 0.001). Time of MVPA varied between methods from 25.3 to 55.2 min · day–1. The number of adolescents fulfilling the recommendation varied from 5.9% to 37% according to the thresholds used. The kappa coefficient for concordance in the assessment of the number of adolescents achieving the PA recommendations was generally low. The definition of the threshold for PA intensity may considerably affect the PA patterns in FLC when assessed using a uniaxial accelerometer and the number of participants fulfilling the recommendations.

Liver enzymes and clustering cardiometabolic risk factors in European adolescents: the HELENA study

This study aimed to explore the associations of liver biomarkers with cardiometabolic risk factors and their clustering, and to provide reference values (percentiles) and cut‐off points for liver biomarkers associated with high cardiometabolic risk in European adolescents.

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

Ingesta de huevo y factores de riesgo cardiovascular en adolescentes; papel de la actividad física: Estudio HELENA

INTRODUCTION Cardiovascular diseases (CVDs) represent the main cause of morbi-mortality in western countries. Serum cholesterol levels have been related to cardiovascular disease (CVD). Egg intake has been indirectly related to the risk of developing CVD because of its high cholesterol content. OBJECTIVE The aim of the present study was to examine the association between egg intake and CVD risk factors in adolescents, assessing the possible influence of physical activity. METHODS We studied 380 adolescents enrolled in the HELENA (HEalthy Lifestyle in Europe by Nutrition in Adolescence) study. Food intake was estimated by 2 nonconsecutive 24 h recalls. We measured adiposity indicators, lipid profile, blood glucose and insulin levels, insulin resistance, blood pressure and cardiorespiratory fitness. A CVD risk score was computed as a measure of the overall CVD risk profile. Physical activity was objectively measured by accelerometry. Sexual development was examined. Socioeconomic and smoking statuses were obtained by questionnaire. The association between egg intake and CVD risk factors was examined using a multilevel analysis adjusted for potential confounders. RESULTS Egg intake was not associated with lipid profile, adiposity, insulin resistance, blood pressure, cardiorespiratory fitness or the integrated CVD risk score. This lack of association was not influenced by physical activity. CONCLUSIONS The findings of the present study suggest that egg intake is not associated with a less favorable lipid or CVD risk profile in adolescents. This lack of association is not influenced by the level of physical activity.

Response to “Is it possible to determine a ‘powerful marker of health’?”

Dear Editor, we thank Palma and Axis for their interest in our paper. They have started an interesting conceptual discussion. The response to the points raised is basically the answer to three key questions: (1) what is health?, (2) what is fitness? and (3) how are these concepts related? (1) Palma and Axis state ‘It is clear that the authors understand health as the absence of illnesses or normality’. We do not agree with this statement. We have a much broader concept of health, in accordance with the World Health Organization’s definition: ‘health is a state of complete physical, mental, and social well-being and not merely the absence of disease, or infirmity’. That is why our review includes concepts such as mental fitness (academic performance and so on), which is nothing to do with illness. We do not either conceive health as a synonymous of normality. A simple example is that elite sport men and women show a totally abnormal physical fitness level while they can be perfectly healthy. (2) We explicitly defined and differentiated physical fitness and exercise in our review. However, Palma and Axis confounded both concepts, as shown in their letter. They state: ‘exercise, when practiced in excess may bring health problems’ (to which we agree), but they add, ‘Therefore, high levels of physical fitness may not represent good health’. The fact that an excess of exercise can have negative consequences does not mean that a high fitness also has negative consequences for health. In fact, there is not an upper limit for physical fitness. Simply stated: the higher the better. This is also the case for mental ‘fitness’ or social well-being, the higher the better. (3) Finally, the question whether physical fitness influences health or it is health that influences fitness is the classical dilemma of ‘what comes first the egg or the hen’. We definitively believe that there is a reciprocal relationship between fitness and health: fitness is important for health and health is important for fitness.