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The aim of the study was to describe anthropometric and physical characteristics of elite young road-race motorcyclists (MC). 27 riders (15.6 ± 1.1 years, 54.6 ± 6.9 kg, 166.9 ± 6.7 cm) competing at international elite level participated in this study. Anthropometric variables, hand grip and lumbar isometric strength, and lower-body muscular strength were measured. Comparisons of the MC and a reference group of Spanish physically active adolescents (16.0 ± 0.6 years) showed that the riders were significantly lighter (-12.5 kg), and smaller (-4.7 cm). Riders also had significantly lower values for almost all skinfolds, and for all the measured girths (except forearm) than the reference group. Motorcyclists showed significantly less percent body fat (%BF) and higher muscle mass, and differences were observed for somatotype components compared to the reference group, except for the ectomorphy. Somatotype could be defined as mesomorphic-ectomorph (2.5-4.4-3.7). Mean (±SD) values of all riders were 34.8 ± 5.0 cm for vertical jump height, 402.1 ± 74.5 N for the right hand and 370.7 ± 77.5 N for the left hand strengths, and 120.6 ± 19.3 kg for lumbar isometric strength, respectively. Results demonstrate that MC are small and light, with lower body mass index, skinfolds, girth and breadth dimensions, and %BF than a reference group and other athletes, with high values of hand grip and lumbar isometric strength. [ABSTRACT FROM AUTHOR]

A group-randomized controlled trial was carried out to investigate the effects of a postural education program on daily life habits related to low back pain in children. The study sample included 137 children aged 10.7 years. 6 classes from 2 primary schools were randomly allocated into an experimental group (EG) (N = 63) or a control group (CG) (N = 74). The EG received a postural education program over 6 weeks consisting of 6 sessions, while the CG followed the usual school curriculum. A questionnaire was completed by the participants at pretest, posttest and 3 months after the intervention finished. The outcomes collected were: correct use of sofa, stooping correctly, take care to sit correctly at home/school and frequent posture change on chair at home/school. A sum score was computed from the 6 items. To examine the effect of the intervention, we used repeated measures analysis of co-variance (ANCOVA); with baseline, post-test and follow-up outcome values as dependent variables, study group as fixed factor, and sex and age as covariates. Single healthy items mostly improved after the intervention and remained improved after 3 month follow-up in EG, while no substantial changes were observed in the CG. Healthy habits score was significantly increased at post-test compared to baseline in the EG (P < 0.001), and remained significantly increased after 3-months, compared to baseline (P < 0.001). No significant changes were observed in the CG (P > 0.6). The results suggest that children are able to learn healthy daily life habits which might contribute to future prevention of low back pain. [ABSTRACT FROM AUTHOR]

The objective of this systematic review was to study the reliability of the existing field-based fitness tests intended for use with children and adolescents. The medical electronic databases MEDLINE, SCOPUS and SPORTS DISCUS were screened for papers published from January 1990 to December 2009. Each study was classified as high, low or very low quality according to the description of the participants, the time interval between measurements, the description of the results and the appropriateness of statistics. 3 levels of evidence were constructed according to the number of studies and the consistency of the findings. 32 studies were finally included in the present review. The reliability of tests assessing cardiorespiratory fitness (9 studies), musculoskeletal fitness (12 studies), motor fitness (3 studies), and body composition (10 studies) was investigated. Although some fitness components warrant further investigation, this review provides an evidence-based proposal for most reliable field-based fitness tests for use with children and adolescents: 20-m shuttle run test to measure cardiorespiratory fitness; handgrip strength and standing broad jump tests to measure musculoskeletal fitness; 4 × 10 m shuttle run test for motor fitness; and height, weight, BMI, skinfolds, circumferences and percentage body fat estimated from skinfold thickness to measure body composition. [ABSTRACT FROM AUTHOR]

The article presents a study on the role of cardiorespiratory fitness (CRF) on the link between physical activity (PA) and abdominal fat content in adolescents. For the study, researchers measured abdominal fat content by waist circumference, waist-to-heigh ratio and dual energy X-ray absoptiometry (DXA) at 3 locations. They found that vigorous PA was inversely linked to waist circumference and waist-to-height ratio. They concluded that it is not clear whether CRF plays a role in the link between PA and abdominal fat in adolescents.

The aim of this study was to determine the reliability, feasibility and safety of a health-related fitness test battery administered by Physical Education (PE) teachers in the school setting. Six PE teachers, from three primary schools and three secondary schools, assessed twice (7 days apart) the 20 m shuttle run, handgrip and standing long jump tests, as well as weight, stature, triceps and subscapular thickness and waist circumference in 58 children (age: 6-11 yr) and 80 adolescents (age: 12-18 yr). Feasibility and safety were assessed by researches by means of direct observation. Significant inter-trial differences were found for the standing long jump test (3.8±12.7cm, P<0.05) and for stature (0.73±0.8cm, P<0.001) in children, and for waist circumference in both children and adolescents (-0.82±1.2cm and -0.35±0.8cm respectively, P=0.001). The feasibility and safety items assessed presented a successful answer. Therefore, the results indicate that health-related fitness tests administered by PE teachers are reliable, feasible and safe to be performed in the school setting. [ABSTRACT FROM AUTHOR]

The purpose of the present study was to examine the criterion-related validity of the sit-and-reach test (SRT) and the modified sit-and-reach test (MSRT) for estimating hamstring flexibility in children and adolescents as well as to determine whether the MSRT is more valid than the SRI. A total of 87 (45 boys and 42 girls) children (6-12 years old) and adolescents (13-17 years old) performed the SRI and the MSRT. Hamstring flexibility was measured with goniometry through the passive straight-leg raise test. Regression analysis was performed to study the association of SRT and MSRT with hamstring flexibility (criterion measure). The SRT was associated with hamstring flexibility in both children (13=1.089, R2=0.281, p=0.001) and adolescents (13=0.690, R2=0.333, p =0.004). The MSRT was also associated with hamstring flexibility in both children (13=1.296, R2=0.298, p<0.001) and adolescents (13=0.588, R2=0.243, p=0.027). It is concluded that the criterion-related validity of the SRT and the MSRT for estimating hamstring flexibility is weak. The present data do not support that the MSRT is a more valid method than the SRT in children and adolescents. [ABSTRACT FROM AUTHOR]

We assessed the criterion related validity of 1/2 mile run/walk (1/2MRW) test for estimating VO2peak in children aged 6-17 years. The criterion related validity of the Fernhall's equation in a sub-group of children aged 10-17 years was also examined. A total of 86 children completed a maximal graded treadmill test and the 1/2MRW test. The cohort was randomly divided into either validation (n=47) or a cross-validation (n=39) group. A regression equation was computed and assessed through several error measures, and the Bland and Altman method. There was no systematic bias in the validation group nor in the cross-validation group (P>0.1). The root mean sum of squared errors (RMSE), and the percentage error were 6.5 ml/kg/mm, and 13.9%, respectively. These figures were very similar in the cross-validation group. The new equation had a lower RMSE and percentage error than the Fernhall's Equation (6.2 vs. 19.7 ml/kg/mm, and 16% vs. 50.4%, respectively, P <0.001). The Fernhall's equation showed a significant underestimation of VO2peak (18.1 ml/kg/mm, P<0.001). In conclusion, the new regression equation is valid for estimating VO2peak from the 1/2MRW time, sex, and body mass index in healthy children aged 6-17 years, and is more accurate than Fernhall's equation in the sample studied. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine whether acute strenuous physical exercise, partially performed under moderate altitude, influences the susceptibility of plasma lipids to peroxidation. Eleven male amateur cyclists took part in a 95-km mountain bike challenge with a cumulative altitude difference of 2340 m. Blood samples were obtained before and immediately after the race in order to determine plasma lipid and lipoprotein concentrations, and to assess the susceptibility of the former to peroxidation. Neither plasma lipid nor lipoprotein levels changed significantly after the race. However, the susceptibility of plasma lipids to peroxidation increased by 71.8%. We concluded that strenuous physical exercise partially performed under hypoxic conditions increases the susceptibility of plasma lipids to peroxidation in untrained subjects. [ABSTRACT FROM AUTHOR]

As a result of an unhealthy diet and limited physical activity, obesity has become a widespread pandemic worldwide and is an important predictor for the development of cardiovascular disease. Obesity is often characterized by a pro-inflammatory environment in white adipose tissue (WAT), mainly due to increased macrophage infiltration. These immune cells boost their lipid concentrations by accumulating the content of dying adipocytes. As the lysosome is highly involved in lipid handling, the progressive lipid accumulation may result in lysosomal stress and a metabolic shift. Recent studies have identified glycoprotein non-metastatic melanoma protein B (GPNMB) as a novel marker of inflammatory diseases. GPNMB is a type I transmembrane protein on the cell surface of various cell types, such as macrophages, dendritic cells, osteoblasts, and microglia, from which it can be proteolytically cleaved into a soluble molecule. It is induced by lysosomal stress via microphthalmia-associated transcription factor and thus has been found to be upregulated in many lysosomal storage disorders. In addition, a clear connection between GPNMB and obesity was recently established. GPNMB was shown to have protective and anti-inflammatory effects in most cases, preventing the progression of obesity-related metabolic disorders. In contrast, soluble GPNMB likely has the opposite effect and promotes lipogenesis in WAT. This review aims to summarize and clarify the role of GPNMB in the progression of obesity and to highlight its potential use as a biomarker for lipid-associated disorders. [ABSTRACT FROM AUTHOR]

The aims of the study were to examine the moderating role of physical activity in the relationship between cardiometabolic risk factors and adiponectin concentration in adolescents. This is a cross-sectional study conducted with 96 adolescents of both sexes, between 11 and 17 years old. Body mass, height, fat mass (FM), fat-free mass, systolic blood pressure, diastolic blood pressure, high density lipoprotein, low density lipoprotein (LDL-c), triglycerides, insulin, adiponectin, C-reactive protein, and level of physical activity (energy expenditure questionnaire) were measured. Body mass index (BMI), triponderal mass index (TMI), homeostasis model to assessment insulin resistance (HOMA-IR), and quantitative insulin sensitivity check index (QUICKI) were calculated. Macro-PROCESS for SPSS was used for moderation analyses. Direct interactions were found for BMI, TMI, FM, insulin, and HOMA-IR and inverse for LDL-c, and QUICKI. Protection against cardiometabolic risk was found when the PA-coeff was completed above 1.57 coeff (BMI), 1.62 coeff (TMI), 1.55 coeff (FM), 1.41 coeff (LDL-c)1.60 coeff (insulin), 1.59 coeff (HOMA-IR) and 1.35 coeff (QUICKI). We conclude that physical activity was a moderator in the relationship with adiposity, insulin resistance and sensitivity, LDL-c, and adiponectin. In this context, we evidenced a relevant clinical impact on the health of adolescents, demonstrating the interaction between anthropometrics variables and physical activity. [ABSTRACT FROM AUTHOR]

Low physical fitness in adolescence is linked with increased cardiometabolic risk and early all-cause mortality. This study aimed to estimate temporal trends in the physical fitness of Hong Kong adolescents aged 12–17 years between 1998 and 2015. Physical fitness (9-min run/walk, sit-ups, push-ups, and sit-and-reach) and body size data in a total of 28,059 adolescents tested across five population-representative surveys of Hong Kong secondary school pupils, were reported. Temporal trends in means were estimated at the gender-age level by best-fitting sample-weighted linear regression, with national trends estimated by a post-stratified population-weighting procedure. Overall, there were small declines in 9-min run/walk (effect size (ES)=−0.29 (95%CI: −0.32, −0.26)) and sit-ups performance (ES=−0.24 (95%CI: −0.27, −0.21)), with negligible changes in push-ups and sit-and-reach performance. There were small concurrent increases in both mean height and body mass, with a negligible increase in sum of skinfolds. Trends in mean physical fitness and body size/were not always uniform across the population distribution. The small declines in mean 9-min run/walk and sit-ups performance for Hong Kong adolescents are suggestive of corresponding declines in cardiorespiratory fitness and abdominal/core endurance, respectively. Increased national health promotion strategies are required to improve existing trends. [ABSTRACT FROM AUTHOR]

Although studies used machine learning algorithms to predict performances in sports activities, none, to the best of our knowledge, have used and validated two artificial intelligence techniques: artificial neural network (ANN) and k-nearest neighbor (KNN) in the running discipline of marathon and compared the accuracy or precision of the predicted performances. Official French rankings for the 10-km road and marathon events in 2019 were scrutinized over a dataset of 820 athletes (aged 21, having run 10 km and a marathon in the same year that was run slower, etc.). For the KNN and ANN the same inputs (10-km race time, body mass index, age and sex) were used to solve a linear regression problem to estimate the marathon race time. No difference was found between the actual and predicted marathon performances for either method (p> 0,05). All predicted performances were significantly correlated with the actual ones, with very high correlation coefficients (r >0,90; p <0,001). KNN outperformed ANN with a mean absolute error of 2,4 vs 5,6%. The study confirms the validity of both algorithms, with better accuracy for KNN in predicting marathon performance. Consequently, the predictions from these artificial intelligence methods may be used in training programs and competitions. [ABSTRACT FROM AUTHOR]

We aimed to examine speed of movement and its interactive association with fatness to changes in cardiometabolic risk factors over one year in children. The analysis included 8345 children aged 6–13 years. Cardiometabolic risk score was computed by summing Z-scores of waist circumference, the average of systolic and diastolic blood pressure, fasting glucose, high-density lipoprotein cholesterol (multiplied by −1), and triglycerides. Both high baseline and improvement in speed of movement were associated with favourable changes in percent body fat, lipids, and cardiometabolic risk score. Percentages of the association between baseline speed of movement and changes in cardiometabolic risk score, triglycerides, and high-density lipoprotein cholesterol explained by baseline BMI were 24.6% (19.6–29.1%), 26.2% (19.7–31.1%), and 12.5% (9.6–15.4%), respectively. The corresponding number for percent body fat was 47.0% (40.4–54.1%), 43.3% (36.7–51.7%), and 29.8% (25.0–34.6%), respectively. Speed of movement mediated the association between fatness and cardiometabolic risk factors. Improved speed of movement was associated with a lower increase in blood pressure in obese children only. Speed of movement is a strong predictor of changes in cardiometabolic risk factors. Fatness and speed of movement are interactively associated with cardiometabolic risk factors. Speed of movement may attenuate the positive association between fatness and blood pressure. [ABSTRACT FROM AUTHOR]

Background Risk factors control and secondary prevention measures are often reported to be suboptimal in patients undergoing coronary artery bypass grafting (CABG) and may lead to worse clinical outcomes. We aimed to examine potentially modifiable risk factors in patients undergoing CABG and investigate their association with long-term coronary events. Methods Cardiovascular risk factors were recorded preoperatively in the setting of a cardiac catheterization laboratory and were analyzed in relation to long-term coronary events, defined as acute coronary syndrome (ACS) or revascularization after CABG. Results Study population included 1,125 patients undergoing CABG without previous revascularization. Modifiable risk factors included hypertension (71%), hyperlipidemia (67%), diabetes (42%), obesity (28%), and smoking (21%). Only 8% did not have any of the five risk factors. During the mean follow-up of 93 ± 52 months after CABG, 179 patients (16%) experienced a coronary event. Incidence rates were higher in patients with than without the presence of each of the modifiable risk factors, except obesity. Active smoking (hazard ratio [HR]: 1.51; 95% confidence interval [CI]: (1.07–2.13); p = 0.020), presence of diabetes (HR: 1.61; 95% CI: 1.18–2.18; p = 0.002), and hyperlipidemia (HR: 2.13; 95% CI: 1.45–3.14; p < 0.001) were independent predictors of future coronary events after CABG; they also displayed a progressive stepwise increment in the risk of long-term coronary events when cumulatively present. Conclusions In patients undergoing CABG, diabetes, hyperlipidemia, and smoking, as documented preoperatively, were potentially modifiable risk factors that were independently and cumulatively associated with long-term risk of ACS or coronary revascularization, highlighting the importance of early identification and risk factors control for improving cardiovascular health after CABG. [ABSTRACT FROM AUTHOR]

The theoretical background related to how physical activity positively influences children and adolescents' brain function for social and emotional competency has been stably structured. However, according to our review of the literature, no study has synthetically analyzed physical education interventions that produce positive outcomes related to learners' emotional status. Therefore, the aim of the study was to systematically analyze the effectiveness of physical education interventions designed to improve students' emotional ability. In October 2017, we searched electronic research databases for intervention studies that analyzed the impact of school physical education on students' emotional changes. We assessed the risk of bias, extracted data, and conducted meta-analysis to determine the effectiveness of physical education intervention. From an initial pool of 1200 non-duplicate records, 12 studies fulfilled the inclusion criteria. The effectiveness of school-based physical education was analyzed by calculating standard mean difference. Based on the results of the meta-analysis, students in intervention conditions changed their psychological conditions compared with students in usual practice conditions (standardized mean difference=0.30, 95% confidence interval=− 0.05−0.66). Physical and sport education for children and adolescents has positively influenced changes in their emotional conditions. [ABSTRACT FROM AUTHOR]

The aim of the study was to investigate factors related to the occurrence of nighttime hypoglycemia after a football tournament in children with type 1 diabetes mellitus. The multicenter study (GoalDiab study) included 189 children and adolescents with type 1 diabetes mellitus, from 11 diabetes care centers in Poland. Hypoglycemia was defined according to the International Hypoglycemia Study Group Statement. We analyzed the data of 95 participants with completed protocols with regards to nighttime hypoglycemia (82% male), aged 11.6 (9.8–14.2) years, diabetes duration 5.0 (2.0–8.0) years. There were 47 episodes of nighttime Level 1 hypoglycemia (≤3.9 mmol/L). Occurrence of clinically important Level 2 hypoglycemia (<3.0 mmol/L) during a game period was positively associated with nighttime hypoglycemia (≤3.9 mmol/L) incident (Odds Ratio=10.7; 95% Confidence Interval: 1.1–100.2; p=0.04). Using Continuous Glucose Monitoring was negatively associated with the occurrence of nighttime hypoglycemia (≤3.9 mmol/L) compared with using glucose meters or Flash Glucose Monitoring (Odds Ratio=0.31; 95% Confidence Interval: 0.12–0.83; p=0.02). The occurrence of clinically important hypoglycemia related to physical activity is associated with the occurrence of hypoglycemia during the night. Continuous Glucose Monitoring is negatively associated with nighttime hypoglycemia after a day of competition. [ABSTRACT FROM AUTHOR]

The university stage is a critical developmental period for young adults, where lifestyles can determine future health. A cross-sectional study including 481 college students was conducted, with the following objectives: 1) to examine the prevalence of risk of developing eating disorders in college students, 2) to assess differences in obesity and physical fitness in those with and without risk of eating disorders, and 3) to determine whether cardiorespiratory fitness, muscular fitness or fat mass were associated with the risk of eating disorders. We measured fat mass percentage (by densitometry), risk of feeding or eating disorders (by SCOFF questionnaire), cardiorespiratory fitness levels and a muscular fitness index. The prevalence of risk of eating disorders in women (32.4%) was higher than in men (17.4%) (p<0.001). In both sexes, higher obesity indicator mean values were observed among those who were at risk of eating disorders. Men participants without risk had higher cardiorespiratory fitness means than their at-risk peers [39.4 (8.3) vs. 32.4 (5.5), p<0.001)], and women showed differences only in the dynamometry/weight variable. In college students, it is necessary to promote healthy habits, including good levels of physical fitness, and to prevent excess body fat to effectively prevent eating disorders. [ABSTRACT FROM AUTHOR]

BMIz-score (BMIz) is commonly used to assess childhood obesity. Whether change in BMIz score predicts change in visceral fat remains unclear. The objective of the work was to study changes in visceral fat, cardiovascular fitness (CVF), and metabolic health over 6 months in children with stable/decreased-BMIz vs. increased-BMIz. Ninety children with obesity, referred for lifestyle intervention were studied (mean age 11±3.1 years, 50% girls, 22% Hispanic). Assessment included abdominal and total fat by dual X-ray absorptiometry (DXA), sub-maximal VO2 for CVF, anthropometrics, and fasting insulin, glucose, HDL-C, triglycerides, AST and ALT at 0 and 6 months. Sixty-three children (70%) showed a stable/decrease in BMIz over 6 months. There was no significant change in total body fat between groups (−1.3±2.9% in BMIz-stable/down vs. − 0.6 ± 2.6% BMIz-up, p=0.459); however, BMIz-stable/down group showed a decrease in visceral fat compared to the BMIz-up group (−258±650 g vs.+137±528 g, p=0.009). BMIz-stable/down group also demonstrated increased CVF (+1.2 ml/kg/min, p<0.001), not seen in the BMIz-up group. Neither group had significant changes in metabolic markers. Preventing BMIz increase in obese children predicts a significant decrease in visceral fat even if total body fat is unchanged. This is often associated with increased fitness. Thus, increasing fitness level and keeping BMI stable are strategic initial goals for obese children. [ABSTRACT FROM AUTHOR]

The aims of this study were to analyse the effect of chronic strength training over concentric power (CON), eccentric power (ECC), ECC/CON ratio, and 20 m linear sprint performance in elite young soccer players. Twenty young elite Spanish soccer players were assigned to an experimental group (CPG) which performed a front-step exercise using a conical pulley, 2–3 sets of 6 repetitions each leg, during 9 weeks (CPG, n=10) in addition to its usual strength training, or to a control group (CG, n=10). The improvements in the ECC mean power (36%, ES=1.61), and ECC / CON ratio (17%, ES=1.77) were substantially greater in the CPG than in the CG while the CON mean power (16%, ES=0.83) was substantially greater in the CG than in the CPG. The sprinting time for 10 m (2.8%, ES=0.78) and the 10 m flying time between 10–20 m (1.72%, ES=0.41) were substantially enhanced in CPG and CG respectively. To be efficient when defining a functional strength training and performance increments using an inertial device, the mean power output need to be measured during the CON and ECC phases and an analysis of the ECC / CON ratio should be included. [ABSTRACT FROM AUTHOR]

The aim was to study associations of maximal strength and muscular endurance with inflammatory biomarkers independent of cardiorespiratory fitness in those with and without abdominal obesity. 686 young healthy men participated (25 ± 5 years). Maximal strength was measured via isometric testing using dynamometers to determine maximal strength index. Muscular endurance index consisted of pushups, sit-ups and repeated squats. An indirect cycle ergometer test until exhaustion was used to estimate maximal aerobic capacity (VO2 max). Participants were stratified according to those with ( > 102 cm) and those without abdominal obesity ( < 102 cm) based on waist circumference. Infl ammatory factors (C-reactive protein, interleukin- 6 and tumour necrosis factor alpha) were analysed from serum samples. Maximal strength and muscular endurance were inversely associated with IL-6 in those with (β = - 0.49, - 0.39, respectively) (p < 0.05) and in those without abdominal obesity (β = - 0.08, - 0.14, respectively) (p < 0.05) adjusted for smoking and cardiorespiratory fitness. After adjusting for smoking and cardiorespiratory fitness, maximal strength and muscular endurance were inversely associated with CRP only in those without abdominal obesity (β = - 0.11, - 0.26, respectively) (p < 0.05). This cross-sectional study demonstrated that muscular fitness is inversely associated with C-reactive protein and IL-6 concentrations in young adult men independent of cardiorespiratory fitness. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine if month of birth affects performance in 3 tests of physical function in children and adolescents. We measured cardiorespiratory fitness, handgrip strength and lower-body power expressed them relative to (whole year) age then compared scores between calendar year birth-months. We also expressed test performance as the likelihood of achieving criterion-referenced fitness standards. There were significant main effects of birth-month for cardiorespiratory fitness (F = 4.54, p < 0.001), strength (F = 6.81, p < 0.001) and power (F = 3.67, p < 0.001). Children born in November were fitter and more powerful than those born at other times, particularly the summer months (April, May and June). October-born children were stronger than those born in all months except September and November. This relationship was evident despite controlling for decimal age and despite no significant inter-month differences in anthropometric characteristics. There is a clear physical advantage for those born in the autumn and this may explain some of the bias in sports selection attributed to the relative age effect, particularly when the British school-year (September) cut-off is used. [ABSTRACT FROM AUTHOR]

We investigated the renal effects of a high-intensity exercise (HIE) program based on strength training. 20 Wistar rats were randomly assigned to 2 experimental groups performing HIE or control over 12 weeks. Urinary volume, pH, citrate and calcium, and plasma urea, total proteins, creatinine, albumin, lactate dehydrogenase, creatine kinase (CK), calcium, magnesium, corticosterone and testosterone were measured. We also studied renal morphology with the Fibrosis HR ® software. Plasma urea and CK concentrations were higher in the HIE compared to the control group (p < 0.05), whereas plasma creatinine was lower (p < 0.01). Plasma corticosterone was higher (p < 0.05) and testosterone lower (p < 0.01) in the HIE group. Except for the higher urinary volume found in the HIE group (p < 0.05), no differences between groups were observed in the rest of urinary parameters analyzed. Renal interstitial connective tissue was ~30 % higher in the HIE group (p < 0.05). Glomerular tufts and mesangial areas were also higher in the HIE group (all, p < 0.05). No differences between groups were observed in the glomerular area. Overall, HIE promoted a worse morphological renal profile that might be associated with a higher risk for incidence of kidney disease in the long-term. The stress induced by the type of exercise performed could be on the basis of this worse morphological renal status. [ABSTRACT FROM AUTHOR]

The objectives were 1) to evaluate the hamstring muscle flexibility in children and adolescents; 2) to examine the relative contribution of the spinal curvatures, pelvic tilt and hamstring flexibility on the sit-and-reach (SR) score; and 3) to determine the validity of the sit-and-reach test through both active and passive hip flexion tests. 118 children and adolescents (aged 7–18 years; 60 males and 58 females) were tested for sit-and- reach (SR), passive straight leg raise (PSLR) and active straight leg raise (ASLR). The spinal curvatures and pelvic tilt were assessed during the SR test by means of the Spinal Mouse system. Females showed a statistically greater anterior pelvic tilt, distance reached in the SR test and hip flexion in both PSLR and ASLR tests than males. The pelvic tilt independently explained more than 60 % of the variance (distance reached in the SR test) and in conjunction with lumbar flexion explained more than 80 % of the variance. In conclusion, the pelvic tilt is the main determinant of SR test in school age children. The SR test can be considered an appropriate and valid test for evaluating pelvic tilt and lumbar flexion in school age children, but not to measure hamstring flexibility. [ABSTRACT FROM AUTHOR]

Tai-Chi has shown benefits in physical and psychological outcomes in diverse populations. We aimed to determine the changes elicited by a Tai-Chi program (12 and 24 weeks) in acute pain (before vs. after session) in fibromyalgia patients. We also assessed the cumulative changes in pain brought about by a Tai-Chi program. Thirty-six patients (29 women) with fibromyalgia participated in a low-moderate intensity Tai-Chi program for 12 weeks (3 sessions/week). Twenty-eight patients (27 women) continued the program for an additional 12 weeks (i. e., 24 weeks). We assessed pain by means of a Visual Analogue Scale (VAS) before and after each single session (i. e., 72 sessions). We observed significant immediate changes (P-values from 0.037 to 0.0001) with an approximately 12% mean decrease of acute pain in the comparison of VAS-values before and after each session (72 sessions in total), with the exception of 4 sessions. We observed significant changes in cumulative pain pre-session (95% CI = -0.019; -0.014; P < 0.001) and cumulative pain post-session (95% CI = -0.021; -0.015; P < 0.001) along the 24-week intervention only. In conclusion, a low-moderate intensity Tai-Chi program for 12 weeks (3 times/ week) decreased levels of acute pain in fibromyalgia patients. A longer period is necessary (e. g. 24 weeks) for observing cumulative changes in pain. [ABSTRACT FROM AUTHOR]

The aim was to study the associations of maximal strength and muscular endurance with single and clustered cardiovascular risk factors. Muscular endurance, maximal strength, cardiorespiratory fi tness and waist circumference were measured in 686 young men (25 ± 5 years). Cardiovascular risk factors (plasma glucose, serum high- and low-density lipoprotein cholesterol, triglycerides, blood pressure) were determined. The risk factors were transformed to z-scores and the mean of values formed clustered cardiovascular risk factor. Muscular endurance was inversely associated with triglycerides, s-LDL-cholesterol, glucose and blood pressure (β = - 0.09 to - 0.23, p < 0.05), and positively with s-HDL cholesterol (β = 0.17, p < 0.001) independent of cardiorespiratory fi tness. Muscular endurance was negatively associated with the clustered cardiovascular risk factor independent of cardiorespiratory fi tness (β = - 0.26, p < 0.05), whereas maximal strength was not associated with any of the cardiovascular risk factors or the clustered cardiovascular risk factor independent of cardiorespiratory fi tness. Furthermore, cardiorespiratory fi tness was inversely associated with triglycerides, s-LDLcholesterol and the clustered cardiovascular risk factor (β = - 0.14 to - 0.24, p < 0.005), as well as positively with s-HDL cholesterol (β = 0.11, p < 0.05) independent of muscular fi tness. This cross-sectional study demonstrated that in young men muscular endurance and cardiorespiratory fi tness were independently associated with the clustering of cardiovascular risk factors, whereas maximal strength was not. [ABSTRACT FROM AUTHOR]

Objective: To investigate whether physical fitness and/or fat distribution and inflammation profile may explain why approximately 30 % of the women with obesity are protected against obesity-related disorders. Method: 10 metabolically healthy obese women and 10 age- and weight-matched women with the metabolic syndrome were enrolled. Physical fitness (VO2max ), daily physical activity levels (METs, steps per day), insulin sensitivity (clamp), body fat distribution (DXA scan) and, inflammation markers and adipokines were determined. Results: The metabolically healthy obese women had a 17 % higher VO2max (25.1 ± 3.9 vs. 21.5 ± 3.1 ml · min -1· kg -1, p = 0.04) and tended to take more steps per day (7 388 ± 1 440 vs. 5 927 ± 1 301, p = 0.06) than women with the metabolic syndrome. Despite equivalent levels of fat mass, metabolically healthy obese women had significantly lower circulating TNF-α levels compared to women with the metabolic syndrome (3.55 ± 3.83 vs. 0.43 ± 0.97 ng/ml, p = 0.03). No differences were seen in insulin sensitivity, adipokines, and inflammatory markers between both groups. Conclusion: Metabolically healthy obese women have a higher cardio-respiratory fitness and lower TNF-α levels, which may partly explain why these women are protected from the detrimental effects of obesity compared to obese women with the metabolic syndrome. [ABSTRACT FROM AUTHOR]

Information regarding osteogenic effects of physical activity performed on different playing surfaces is scarce. A total of 42 children (9.2 ± 0.2 years, Tanner stages I-II) participated in this study. 14 were playing on artificial turf soft ground (SG), 14 on a natural non-grass hard ground (HG) and 14 were assigned to the sedentary control group (C). Whole body and hip scans (dual energy X-ray absorptiometry), anthropometric variables (weight and height) and physical fitness (VO2max) were determined in all participants. Bone mineral content (BMC) values were higher in the SG group compared to the C group at the legs (209.75 ± 5.11 g vs. 187.42 ± 5.14 g, respectively), pelvis (122.72 ± 4.27 g vs. 98.58 ± 4.29 g respectively) and whole-body level (1 126.1 ± 22.81 g vs. 1 035.34 ± 22.92 g, respectively). The hard ground (HG) group also showed higher values in the majority of BMC variables compared to the C group. Additionally, bone mineral density (BMD) was significantly higher at all sites of the hip in both active groups compared to control (P < 0.05). No differences between HG and SG were found. In summary, similar bone mass accretion is obtained by prepubescent footballers independently of the surface on which they practice football. [ABSTRACT FROM AUTHOR]

The aims of this study were: to compare energy expenditure (EE) estimated from the existing GT3X accelerometer equations and EE measured with indirect calorimetry; to define new equations for EE estimation with the GT3X in youth, adults and older people; and to define GT3X vector magnitude (VM) cut points allowing to classify PA intensity in the aforementioned age-groups. The study comprised 31 youth, 31 adults and 35 older people. Participants wore the GT3X (setup: 1-s epoch) over their right hip during 6 conditions of 10-min duration each: resting, treadmill walking/running at 3, 5, 7, and 9 km · h -1, and repeated sit-stands (30 times · min -1). The GT3X proved to be a good tool to predict EE in youth and adults (able to discriminate between the aforementioned conditions), but not in the elderly. We defined the following equations: for all age-groups combined, EE (METs) = 2.7406 + 0.00056 · VM activity counts (counts · min -1) -- 0.008542 · age (years) -- 0.01380 · body mass (kg); for youth, METs = 1.546618 + 0.000658 · VM activity counts (counts · min -1); for adults, METs = 2.8323 + 0.00054 · VM activity counts (counts · min -1) -- 0.059123 · body mass (kg) + 1.4410 · gender (women = 1, men = 2); and for the elderly, METs = 2.5878 + 0.00047 · VM activity counts (counts · min -1) -- 0.6453 · gender (women = 1, men = 2). Activity counts derived from the VM yielded a more accurate EE estimation than those derived from the Y-axis. The GT3X represents a step forward in triaxial technology estimating EE. However, age-specific equations must be used to ensure the correct use of this device. [ABSTRACT FROM AUTHOR]

The purpose of this study was to compare the effects of an 8-weeks training period of resistance training alone (GR), combined resistance and endurance training (GCON) and a control group (GC) on explosive strength and VO2max in a large sample of prepubescent boys and girls. 125 healthy children (58 boys, 67 girls), aged 10-11 years old (10.8 ± 0.4 years) were assigned into 2 training groups to train twice a week for 8 weeks: GR (19 boys, 22 girls), GCON (21 boys, 24 girls) and a control group (GC: 18 boys, 21 girls; no training program). A significant but medium-sized increase from pre- to the post-training in the vertical jump (Effect size = 0.22, F = 34.44, p < 0.01) and VO2max (Effect size = 0.19, F = 32.89, p < 0.01) was observed. A significant large increase in the 1 kg (Effect size = 0.53, F = 202.17, p < 0.01) and 3 kg (Effect size = 0.48, F = 132.1, p < 0.01) ball throwing, standing long jump (Effect size = 0.53, F = 72.93, p < 0.01) and running speed (Effect size = 0.45, F = 122.21, p < 0.01) was also observed. The training group (GR and GCON) and sex factors did not significantly influence the evolution of strength variables from pre- to the post-training. The VO2max increased significantly only in GCON. Concurrent training is equally effective on training-induced explosive strength, and more efficient than resistance training only for VO2max, in prepubescent boys and girls. This should be taken into consideration in order to optimize strength training school-based programs. [ABSTRACT FROM AUTHOR]

This study sought to analyze the associations between cardiorespiratory fitness (CRF), waist circumference (WC) and metabolic risk in children and adolescents. Participants were 633 subjects (58.7 % girls) ages 10-18 years. Metabolic risk score (MRS) was calculated from HDL-cholesterol, triglycerides, fasting glucose and mean arterial pressure. MRS was dichotomized into low and high metabolic risk (HMRS). CRF was defined as the maximal oxygen uptake (VO2max) estimated from the 20 m Shuttle Run Test. The first quartile of CRF was set as the low fitness group. The fourth quartile of WC was defined as high central adiposity. With adjustments for age, sex and WC, CRF was correlated with MRS (r = −0.095; p < 0.05). WC was correlated with MRS (r = 0.150; p < 0.001) after adjustments for age, sex and CRF. Participants who had low fitness levels, presented higher levels of MRS (p < 0.001) compared to those who were fit, even after adjustment for age, sex and WC. In comparison with subjects who were fit with normal central adiposity, an increased odds ratio (OR) for being at HMRS was found for participants who were of low fitness level with high central adiposity (OR = 2.934; 95 %CI = 1.690 −5.092) and for those who were of low fitness with normal central adiposity (OR = 2.234; 95 %CI = 1.116 −4.279). Results suggest that CRF relates to MRS independently of central adiposity. [ABSTRACT FROM AUTHOR]

Fibromyalgia is characterized by chronic and extended musculoskeletal pain. The combination of exercise therapy with the warm water may be an appropriate treatment. However, studies focusing on the analysis of immediate pain during and after an exercise session are rare. This study aimed to determine the immediate changes of a warm water pool-based exercise program (12 weeks) on pain (before vs. after session) in female fibromyalgia patients. 33 Spanish women with fibromyalgia were selected to participate in a 12 weeks (2 sessions/week) low-moderate intensity warm water pool-based program. We assessed pain by means of a Visual Analogue Scale before and after each single session (i. e., 24 sessions). We observed immediate benefits on pain with a mean decrease ~15 % in all sessions, except in the fourth one. There was an association of pain difference (pre-post) session with pain pre session (p = 0.005; β = 0.097 ± 0.034) and with age (p < 0.001; β = 0.032 ± 0.008). There were no significant accumulative differences on pain, pre session, post session, and pre-post changes (all p > 0.05). Therefore this study showed that a warm water pool-based exercise program for 12 weeks (2 times/week) led to a positive immediate decrease in level of pain in female patients with fibromyalgia. Improvements were higher in older women and in those with more intense pain. [ABSTRACT FROM AUTHOR]

This study examined the thigh muscularity and strength capability in early adolescent soccer players. The cross-sectional areas (CSAs) of the thigh muscles and dynamic strength during knee extension and flexion at 1.05 rad/s were determined twice at an interval of 6 months in 24 male soccer players aged 12-13 years and 11 age- and body height-matched non-athletes. After 6 months, muscle CSA and dynamic strength increased without significant interaction of time and group. Thigh total muscle CSA was not significantly affected by group, but the value relative to either thigh CSA or body mass was higher in soccer players. While knee flexion strength was similar between the 2 groups, knee extension strength was greater in soccer players than in non-athletes, even in terms of strength relative to CSA. The current results indicate that, compared with age- and body height-matched non-athletes, early adolescent soccer players are characterized by higher relative distribution of muscle mass within the thigh and higher knee extension strength relative to the quadriceps CSA. During the growth stage in which body height begins to increase markedly, however, participation in competitive soccer training does not increase the rate of development in thigh muscularity and strength. [ABSTRACT FROM AUTHOR]

The validity and reliability of a battery of fieldbased performance tests was examined. The opinions of coaches, fitness professionals and players (n = 170, 172 and 101 respectively) on the importance of performance testing were established using a questionnaire. On 2 occasions, separated by 7 days, 80 elite, young soccer players (mean ± SD [and range]: age 13.2 ± 2.6 [8.9-19.1] years; stature 1.59 ± 0.18 m [1.32-1.91]; body mass 50.6 ± 17.1 [26.5-88.7] kg) completed a battery of fi eld-based tests comprised of heart rate response to a submaximal Multi-stage fi tness test, 3 types of vertical jump, sprints over 10 and 20 m, and an agility test. Physical performance testing was considered important by coaches (97 %), fi tness professionals (94 %) and players (83 %). The systematic bias ratio and the random error components of the 95 % ratio limits of agreement for the fi rst and second tests, for the U9-U11 vs. U12-U14 vs. U15-U18 age groups, were [Systematic bias (*/ ÷ ratio limits)]: Heart rate (Level 5): 0.983 (*/ ÷ 1.044) vs. 0.969 (*/ ÷ 1.056) vs. 0.983 (*/ ÷ 1.055); Rocket jump: 0998 (*/ ÷ 1.112) vs. 0.999 (*/ ÷ 1.106) vs. 0.996 (*/ ÷ 1.093); 10 m sprint: 0.997 (*/ ÷ 1.038) vs. 0.994 (*/ ÷ 1.033) vs. 0.994 (*/ ÷ 1.038); Agility test: 1.010 (*/ ÷ 1.050) vs. 1.014 (*/ ÷ 1.050) vs. 1.002 (*/ ÷ 1.053). All tests, except heart rate recovery from the Multi-stage fi tness test, were able to distinguish between diff erent ability and age groups of players (p < 0.05). Thus, the fi eld-test battery demonstrated logical and construct validity, and was shown to be a reliable and objective tool for assessing elite, young soccer players. [ABSTRACT FROM AUTHOR]

The aim of this study was to analyze longitudinal associations between cardiorespiratory fi tness, physical activity and body mass index in a 4-year longitudinal study. 170 students (97 girls and 73 boys) aged at baseline from 11 to 17 years were followed. Students performed 20-m-SR; physical activity patterns and parents' education were evaluated using a standard questionnaire. Body mass index was categorized according to established cut points. In a multilevel analysis using MLwIN, 2 level structures were defi ned: fi rst for individuals and second for time observations. In a longitudinal 2 level analysis, cardiorespiratory fi tness was negatively associated with body mass index for girls and boys, respectively (p < 0.05; R 2 = 0.63; 0.62), especially with obesity category (p < 0.01; R 2 = 0.58; 0.60). In girls, independent associations were observed between CRF and PA categories regarding participation "almost every day" in organized (p < 0.05; R 2 = 0.50) and non-organized sports outside school (p < 0.05; R 2 = 0.52) and participation in sports competitions (p < 0.05; R 2 = 0.51). In boys, associations were found only with participation in sports competitions (p < 0.05; R 2 = 0.50). The results highlight the importance of youth participation in organized activities and competitive sports over time to achieve health-related fi tness benefi ts. [ABSTRACT FROM AUTHOR]