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Sleep is a key component of athletic recovery, yet training times could influence the sleep of athletes. The aim of the current study was to compare sleep difficulties in athletes across different training time groups (early morning, daytime, late evening, early morning plus late evening) and to investigate whether training time can predict sleep difficulties.

AbstractThis study's objectives were to analyse goal orientation and motivational climate in elite handball players as functions of age and gender; and construct a multivariate model explaining handball performance from a motivational perspective (orientation and climate). The participants were 174 national team handball players. They were categorized in accordance with the official age groups. Two questionnaires were used: Task and Ego Orientation in Sport Questionnaire and the Perceived Motivational Climate in Sport Questionnaire-2. A one-way ANOVA (Bonferroni post-hoc correction) was used to examine differences between teams for each gender. Discriminant analyses were performed to classify the participants of each team into two groups according to their performance level (starters and non-starters). There were no age or gender differences found in goal orientation, and very few differences in motivational climate. Except for the women's U19, U17, and U15 teams, it was possible to predict the performance level (starters and non-starters) in the different age and gender groups, achieving correct classification (55% to 93%). The two variables that were repeated most often (thrice) in the models were ego orientation and task cooperative learning. Coaches might focus on looking for handball players with ego orientation, while a climate of task-oriented motivation should predominate in training sessions.

ABSTRACTThe objectives of this study were (i) to compare water polo game-related statistics by match outcome (winning and losing teams) after the application of the new rules, and (ii) to develop a classification tree model explaining the performance in elite men’s water polo. Forty-eight matches that were played in the 18th FINA World Championships were analysed. The dependent variable was match outcome and the independent variables were the game-related statistics. To determine the differences between the winning and losing teams, a parametric (paired-sample t-test) or non-parametric (Wilcoxon signed-rank test) test was applied, depending on whether or not the variable satisfied normality. The effect sizes (ES) of the differences were calculated. In order to determine which variables best predict the final outcome, a decision tree was constructed. This was a tree based on the supervised learning method called QUEST (Quick, Unbiased, Efficient, Statistical Tree). Ten variables differentiated between winning and losing teams (ES ≥ 0.80): four were related to the effectiveness of throwing, three to the effectiveness of the goalkeeper, and three to other actions. The decision tree correctly classified 83.9% of the teams with the variables GB shots, actions goals, time-outs, and steals.

AbstractThe objectives of this study were (i) to analyse how differences in psychological skills among elite athletes depend on sex and psychological skills training (PST), and (ii) to identify predictors of whether an elite athlete has sought PST. Three hundred and ninety-six Icelandic members of youth and senior national teams (49.2% men 21.4 ± 7.1 years old) in basketball, equestrian sports, football, golf, handball and weightlifting participated in the study. The participants completed a background information questionnaire and the Test of Performance Strategies questionnaire (TOPS). The former collected information about age, sex, sport practiced, and whether or not the respondent used or was interested in using PST. The latter assessed the psychological skills the respondent used in training and competition. An independent-samples t-test was used to compare the means on the TOPS sub-scales between sexes and between the use or not of PST. A forward stepwise logistic regression model was constructed to determine which of the variables (age, sex and TOPS sub-scales) could predict whether or not the sportsperson had used PST. PST was used by 42% of the respondents, but the 90% were interested in this type of training. Golfers used PST the most (56%), and men used PS more than women, especially in competition. It was possible to correctly classify 59% of the cases (23% of the variance explained) as to whether or not the participant used PST using just five variables: relaxation in practice, negative thinking in competition, age, self-talk in competition and imagery in practice.

ABSTRACTThis study’s objectives were to (i) to compare beach handball game-related statistics by match outcome (winning and losing teams) and (ii) to develop a multivariate model explaining the performance in elite men’s beach handball. Seventy-two matches of the VIII Men’s Beach Handball World Championship held in Kazan (Russia) in 2018 were analysed. The dependent variable was match outcome (winning and losing teams), and the independent variables were the game-related statistics. A paired sample t-test was used to examine differences between teams. The effect sizes of the differences were calculated. The data were subjected to a multivariate analysis in the form of a regression and classification tree. The game statistics with the greatest effect size (ES≥0.88) and which differentiated the winning and losing teams were the team’s overall valuation and total points. The classification and regression tree model correctly classified 94.5% of the records on the basis of eight variables distributed over 20 nodes: overall valuation, goalkeeper blocked spin-shots, goalkeeper received spin-shots, goalkeeper received one-pointer, spin-shot goals, specialist goals, blocks, technical fouls. Coaches could apply these results to seek better performance in the goalkeeper position and in two-pointer goals.

AbstractThe purpose of this study was to investigate the association between race-start wall contact time and final performance for each sex as a function of classification and anti-slip start-device use (with or without) in backstroke events of international competitions. Twenty-one international competitions covering a 10-year period (2006–2015) were analysed, retrospectively. The data corresponded to the competition histories of 1723 swimmers. For the contact-time data of each event (50-m, 100-m and 200-m), two-way ANOVAs (sex × classification and sex × start device use) were performed. The Bonferroni post-hoc test was used to compare means, and Pearson’s simple correlation coefficient to determine possible correlations between wall contact times and final performance. The results showed the men to have shorter wall contact times than the women in the 50-m and 100-m events, and that, for the women medallists, their wall contact times were positively correlated with final performance in all events except the 200-m swim without the start device.

Background:One of the most commonly measured markers of inflammation in clinical settings is C-reactive protein (CRP). The purpose of this meta-analysis was to examine the evidence for the effectiveness of physical exercise interventions on modifying the levels of serum CRP in children and adolescents with excess of weight.Methods:Two independent reviewers assessed articles from seven databases. Studies were limited to physical exercise interventions in children and adolescents diagnosed as overweight or obese, and including a comparison control group. Weighted mean difference (WMD) was calculated using random-effects model and potential moderators were explored (i.e., weight status, ages, duration of study, frequency of exercise per week, and duration of session). The heterogeneity of the studies was estimated using Cochran’s Q-statistic and I2.Results:Nine randomized controlled trials met the inclusion criteria (n = 427 youths). Overall, results suggest a nonsignificant trend toward a reduction CRP levels (WMD = -0.72?mg/l; 95% confidence interval: -1.52 to 0.08; P = 0.077). Also, there were not significant moderators of exercise effects on CRP.Conclusion:These results suggest that exercise programs in children and adolescents not mitigate the inflammatory effects of excess weight, although there was a trend toward reduction.

The present study's objective was to track long term (three years intervention and six months “detraining”) the influence of an exercise program with or without diet on the motivation of sedentary obese children. The participants were 27 children (8-11 years), divided into two groups according to the program they followed. The G1 group followed a physical exercise program (three 90-minute sessions per week), and the G2 group this physical exercise program plus a low calorie diet. The participants’ motivation to engage in exercise was measured using the Behavioural Regulation in Exercise Questionnaire-2. Both groups showed improvements in amotivation in the 3rd year and in the detraining period (in the G1 and G2, respectively) and in intrinsic regulation of exercise behaviour (in the G1 and G2, respectively). There were also differences between the two groups in external regulation in the intervention and detraining periods. This appears to be indicative of the appropriateness of long-term physical exercise to generate greater autonomous motivation, and hence changes towards healthy living habits that are stable in time.

This study compared volleyball game-related statistics by outcome (winners and losers of sets) and set number (total, initial, and last) to identify characteristics that discriminated game performance. Game-related statistics from 314 sets (44 matches) played by teams of male 14- to 15-year-olds in a regional volleyball championship were analysed (2011). Differences between contexts (winning or losing teams) and “set number” (total, initial, and last) were assessed. A discriminant analysis was then performed according to outcome (winners and losers of sets) and “set number” (total, initial, and last). The results showed differences (winning or losing sets) in several variables of Complexes I (attack point and error reception) and II (serve and aces). Game-related statistics which discriminate performance in the sets index the serve, positive reception, and attack point. The predictors of performance at these ages when players are still learning could help coaches plan their training.

The use of probiotics (ingested microbes that can modify intestinal microbial populations in a way that benefit the host) has moved from concept to actual demonstration of specific benefits by specific microorganisms for specific populations. It is increasingly clear that these benefits to the host are mostly mediated by the profound effect that intestinal microflora (microbiota) have on gut barrier function and host immune response. Intestinal bacteria are more numerous than the human cells of the host that harbors them. Despite having many potential pathogens in this microflora, humans do not routinely get infected. It is no coincidence that gut-associated immune tissue constitutes approximately 80% of all immunologically active cells in the human host. The gut interacts with intestinal bacteria, both resident and ingested, to develop protective mechanisms (viaimproving gut barrier function and immune stimulation for defense) and appropriate, nonexaggerated responses (viaimmune modulation and immune tolerance) to support host health. The mechanisms of this interaction between host and bacteria are increasingly being unraveled and in great part explain the clinical benefits that have been reported with specific probiotic bacteria by enhancing host defense mechanisms (such as for treatment and prevention of viral diarrhea and reducing risk of necrotizing enterocolitis), mitigating antibiotic-associated diarrhea, and modulating host immune response (such as in allergic disease).

Recent studies have shown reduced breath hydrogen (H2) excretion in methane (CH4)-producing healthy individuals following ingestion of lactulose. This questions the reliability of the breath hydrogen test (BHT) in CH4 excretors, but the relationship between CH4 and H2 excretion in other clinical applications of the BHT is not known. We reviewed BHT results in two groups of subjects: (1) 385 children tested for lactose malabsorption in a hospital setting, and (2) 109 lactose-malabsorbing patients tested with a home kit. The percentage of lactose malabsorbers in group 1 (51%) was the same regardless of CH4-producing status (P=0.97). The BHT data from group 2 showed a positive correlation (r=0.6, P<0.000001) between the magnitude of the rise in CH4 and H2 concentrations, and the H2 excretion curves were significantly higher in the CH4-producing individuals. We conclude that attention to CH4-producing status is not necessary in the interpretation of the lactose BHT.

For centuries, fermentation of milk products using specific bacteria or cultures has been a way to preserve dairy foods. In 1908, Metchnikoff suggested that ingested lactobacilli could displace toxin-producing microorganisms in the gastrointestinal (GI) tract and thus promote health and prolong life (1). In the latter half of this century, evidence mounted in support of the concept that the preservation of gut microflora in animals is necessary to prevent infections. It was recognized that germ-free animals are more susceptible to infection than animals colonized with microflora (2) and that giving fecal suspensions orally to animals could prevent infection (3). Fecal enemas were successfully administered to humans to control C. difficileinfection (4); conversely, it was recognized that antibiotics can alter intestinal flora and induce diarrhea. All this information led to the concept that a healthy or balanced microflora is necessary for maintaining the health of the host; one way to maintain balanced microflora is to ingest exogenous bacteria in order to incorporate them into the gut milieu. Many published observations have claimed a variety of health benefits from several microbial agents. Among the benefits attributed to the consumption of these organisms are improvement of lactose absorption and tolerance, control of intestinal infections, anticarcinogenic properties, anticholesterolemic effects, and improvement of GI motility (5,6). These attributions became part of the nutritional folklore that has conferred upon yogurt and other cultured milk products the status of “health foods.‘’

Infants and young children with HIV infection commonly suffer from gastrointestinal manifestations of their disease. Many HIV infected children have evidence of persistent diarrhoea, malabsorption, malnutrition or growth failure. The aetiology and pathogenesis of gastrointestinal dysfunction in HIV infected children have not been well defined. We performed immunocytochemical analyses on intestinal tissue from 19 HIV-infected children with gastrointestinal dysfunction or growth failure. None of these 19 children had microbial pathogens identified in faecal samples using standard microbiological methods. Intestinal tissues were obtained from the children by biopsy and were examined for antigens fromPneumocystis carinii, cytomegalovirus (CMV) and herpes simplex virus (HSV) using the avidin–biotin-complex immunohistochemical technique and monoclonal or monospecific antibodies. We detected at least one of these pathogens in samples from eight (42%) of 19 HIV infected children.P. cariniiwas the most prevalent pathogen, found in five of the eight HIV infected children. All of the children with intestinal pneumocystis infection were receiving prophylaxis directed at the prevention of pulmonary disease with this organism and none of them were undergoing active pulmonary infection. We also identified CMV antigens in intestinal tissues from four children and HSV antigens in intestinal tissues from one child. Two children were infected with more than one pathogen. On the other hand, none of these pathogens were found in the tissues obtained from 10 HIV-uninfected patients who had intestinal tissues obtained for chronic non-infectious diarrheal and inflammatory diseases (P<0·01, Fisher's exact test). Our findings indicate that some children with HIV infection and gastrointestinal dysfunction may be infected with opportunistic pathogens despite negative analyses employing standard microbiological methods. Our study also indicates that HIV infected children can undergo intestinal infection withP. cariniidespite the administration of standard immunoprophylactic regimens directed at the prevention of infection with this organism.

For centuries, fermentation of milk products using specific bacteria or cultures has been a way to preserve dairy foods. In 1908, Metchnikoff suggested that ingested lactobacilli could displace toxin-producing microorganisms in the gastrointestinal (GI) tract and thus promote health and prolong life (1). In the latter half of this century, evidence mounted in support of the concept that the preservation of gut microflora in animals is necessary to prevent infections. It was recognized that germ-free animals are more susceptible to infection than animals colonized with microflora (2) and that giving fecal suspensions orally to animals could prevent infection (3). Fecal enemas were successfully administered to humans to control C. difficileinfection (4); conversely, it was recognized that antibiotics can alter intestinal flora and induce diarrhea. All this information led to the concept that a healthy or balanced microflora is necessary for maintaining the health of the host; one way to maintain balanced microflora is to ingest exogenous bacteria in order to incorporate them into the gut milieu. Many published observations have claimed a variety of health benefits from several microbial agents. Among the benefits attributed to the consumption of these organisms are improvement of lactose absorption and tolerance, control of intestinal infections, anticarcinogenic properties, anticholesterolemic effects, and improvement of GI motility (5,6). These attributions became part of the nutritional folklore that has conferred upon yogurt and other cultured milk products the status of “health foods.‘’

Self-report questionnaires are used here to measure adolescents' percep tion of their parents along the dimensions of warmth and control and their perception of self. The sample consists of 208 Puerto Rican youths ranging in age from thirteen to nineteen years. As predicted from parental ac ceptance-rejection theory, results show a significant correlation between perceived parental warmth and reported self-esteem and self-adequacy. Contrary to expectations, the data do not support the hypothesized cur vilinear relation between perceived parental control and reported self-ade quacy. The joint effects of perceived parental warmth and perceived parental control turn out to be a better predictor of self-adequacy than either perceived parental warmth or perceived parental control alone.

Malnutrition and growth failure are frequent clinical consequences of human immunodeficiency virus (HIV) infection in children. Tube feeding is a means by which to increase the enteral intake of nutrients. We examined the effect of tube feeding in 18 children, median age 6 months (range, 3–159). Tube feedings were initiated due to growth failure in all, which was also associated with dysfunctional swallowing or aspiration in seven children and gastroesophageal reflux in two. Tube feedings were infused via nasogastric tube (n = 4) or gastrostomy tube (n = 14) and were continued for a median of 8.5 months (range, 2–24). Stoma complications developed in three children with gastrostomy tubes; these were the only tube-related side effect. Tube feedings were discontinued due to noncompliance (n = 3), gastrostomy leakage (n = 2), intolerance (n = 2), and death (n = 3). Anthropometric changes were evaluated comparing mean standard deviation scores (Z) before and after tube feeding. Tube feeding resulted in significantly increased weight for age (Z, −2.13 0.7 vs. −1.46 1.4; p = 0.04), weight for height (Z, −1.07 1.0 vs. −0.13 1.0; p = 0.004), and arm fat area (Z, −1.75 1.3 vs. −0.62 1.2; p = 0.01). However, tube feeding did not result in significant changes in height for age (Z, −1.93 0.8 vs. −1.74 1.6) or arm muscle area (Z, −1.24 0.9 vs. −0.57 1.2). Tube feedings effectively increased the weight of HIV-infected children in this study, but they were not sufficient to correct linear growth deficits.

Microvillus inclusion disease is a rare congenital disorder that presents with severe diarrhea in the newborn period. Multiple therapeutic attempts to control the diarrhea have failed, leading to a chronic dependence on parenteral nutrition and a high infant mortality. This report presents the first child with microvillus inclusion disease in whom small bowel transplantation has been successful, allowing for the administration of total caloric requirements via the enteral route.

Malnutrition and growth failure are frequent clinical consequences of human immunodeficiency virus (HIV) infection in children. Tube feeding is a means by which to increase the enteral intake of nutrients. We examined the effect of tube feeding in 18 children, median age 6 months (range, 3–159). Tube feedings were initiated due to growth failure in all, which was also associated with dysfunctional swallowing or aspiration in seven children and gastroesophageal reflux in two. Tube feedings were infused via nasogastric tube (n = 4) or gastrostomy tube (n = 14) and were continued for a median of 8.5 months (range, 2–24). Stoma complications developed in three children with gastrostomy tubes; these were the only tube-related side effect. Tube feedings were discontinued due to noncompliance (n = 3), gastrostomy leakage (n = 2), intolerance (n = 2), and death (n = 3). Anthropometric changes were evaluated comparing mean standard deviation scores (Z) before and after tube feeding. Tube feeding resulted in significantly increased weight for age (Z, -2.13 + 0.7 vs. -1.46 + 1.4; p = 0.04), weight for height (Z, -1.07 + 1.0 vs. -0.13 + 1.0; p = 0.004), and arm fat area (Z, -1.75 + 1.3 vs. -0.62 + 1.2; p = 0.01). However, tube feeding did not result in significant changes in height for age (Z, -1.93 + 0.8 vs. -1.74 + 1.6) or arm muscle area (Z, -1.24 + 0.9 vs. -0.57 + 1.2). Tube feedings effectively increased the weight of HIV-infected children in this study, but they were not sufficient to correct linear growth deficits.

• This study was undertaken to evaluate the usefulness of skin turgor or capillary refilling in estimating the degree of dehydration in infants with diarrhea. After initial standardization of the technique, capillary filling time was found to be more reproducible when measured in the fingernail bed after applying just the amount of pressure necessary to blanch the nail bed. Capillary refilling time in 30 normal infants 2 to 24 months of age was 0.81± 0.31 seconds. Capillary filling time was then measured in 32 infants with diarrhea admitted to the hospital and correlated to the degree of dehydration as estimated from the difference in weight from the time of hospital admission to the weight after rehydration. A turgor time of 1.5 seconds or less was found to be indicative of a less than 50-mL/kg deficit or of a normal infant; 1.5 to 3.0 seconds suggests a deficit between 50 and 100 mL/kg, and more than 3 seconds suggests a deficit of more than 100 mL/kg.(AJDC. 1991;145:296-298)

The prevalence of impaired growth was evaluated in 63 patients with homozygous sickle cell anemia. Twenty-five percent of the children studied were less than the fifth percentile of National Center for Health Statistics growth standards for either height/age, weight/age, or weight/height. Significantly more 11- to 18-year-old children were less than the fifth percentile for weight/height compared with earlier age ranges. No differences due to gender were found. Nutritional intervention may improve growth in selected children.

Answers questions on children's health-related issues. Danger of growth hormones in beef; Frequent vomiting by a nine-month-old son; Treatment for blocked tear ducts; Causes and treatment for dandruff.