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Background/objectives To test the diagnostic ability of two combined practical markers for elevated urine osmolality (underhydration) in free-living adults and children. Subjects/methods One hundred and one healthy adults (females n = 52, 40 [plus or minus] 14 y, 1.70 [plus or minus] 0.95 m, 76.7 [plus or minus] 17.4 kg, 26.5 [plus or minus] 5.5 kg/m.sup.2) and 210 children (females = 105, 1.49 [plus or minus] 0.13 m, 43.4 [plus or minus] 12.6 kg, 19.2 [plus or minus] 3.2 kg m.sup.-2) collected urine for 24-h. Urine was analyzed for urine osmolality (UOsm), color (UC), while the number of voids (void) was also recorded. Receiver Operating Characteristic (ROC) analysis was performed for UC, void, and combination of UC and void, to determine markers' diagnostic ability for detecting underhydration based on elevated UOsm (UOsm [greater than or equal to] 800 mmol kg.sup.-1). Results Linear regression analysis revealed that UC was significantly associated with UOsm in both adults (R.sup.2 = 0.38; P < 0.001) and children (R.sup.2 = 0.45; P < 0.001). Void was significantly associated with UOsm in both adults (R.sup.2 = 0.13; P < 0.001) and children (R.sup.2 = 0.15; P < 0.001). In adults, when UC > 3 and void 3 and void Conclusions Urine color alone and the combination of urine color with void number can a valid and simple field-measure to detect underhydration based on elevated urine osmolality., Author(s): J. D. Adams [sup.1] , Giannis Arnaoutis [sup.2] , Evan C. Johnson [sup.3] , Lisa T. Jansen [sup.4] [sup.5] , Dimitris Bougatsas [sup.2] , Catalina Capitan-Jimenez [sup.6] , Andy [...]

Nutrition affects both body composition and, consequently, athletic performance. Only a few studies have assessed the nutritional behavior and knowledge of elite players. The present study aimed to assess the dietary intake, body composition, and nutritional knowledge of elite handball players. Thirty-nine handball players (age: 23.2 ± 2.7 years, weight: 88.2 ± 10.1 kg, height: 1.87 ± 0.07 m, and years of training: 13 ± 2) participated in the study. The athletes completed a set of anthropometric measurements, a 24 h food recall, and a translated edition of Abridged Nutrition for Sport Knowledge Questionnaire (A-NSKQ). The average body fat percentage was 16.7 ± 3.8%, while the average fat free mass was 73.9 ± 8.5 kg. The athletes' average daily energy intake was 2606.6 ± 756 kcal, while the average daily intake for carbohydrates, proteins, and fats was 243.85 ± 107.79 g [2.8 ± 1.3 g/kg BW/d—37.2 ± 10.5% of Total Energy Intake (TEI)], 131.59 ± 53.28 g (1.51 ± 0.7 g/kg BW/d—20.3 ± 6.9% of TEI), and 117.65 ± 40.52 g (40.9 ± 9.9% of TEI), respectively. For iron, calcium, and vitamin D, the average daily intakes were 19.33 ± 10.22 mg, 1287.7 ± 676.42 mg, and 3.22 ± 3.57 mcg respectively. The average success rate on the A-NSKQ was only 38.5 ± 10.7% out of 100. Elite handball players exhibit inadequate dietary intake and sports nutrition knowledge. Nutritional education should be a primary concern towards the amelioration of their athletic performance. [ABSTRACT FROM AUTHOR]

Background/objectives Children consume various fluids to meet dietary water intake needs. However, the contribution of different fluid types on hydration is unclear. The purpose of this study was to develop fluid intake patterns and examine their association with hydration, as indicated by 24-h urine osmolality. Subjects/methods Two hundred ten (105 girls) healthy children (height: 1.49 [plus or minus] 0.13 m, weight: 43.4 [plus or minus] 12.6 kg, body fat: 25.2 [plus or minus] 7.8%) recorded their fluid intake for two consecutive days, and collected their urine for 24-h during the 2nd day, while conducting their normal daily activities. Urine samples were analyzed for specific gravity and osmolality. Factor analysis with principal components method was applied to extract dietary patterns from six fluid groups. Linear regression analysis evaluated the associations between the extracted dietary patterns and hydration based on 24-h urine osmolality. Results The analysis revealed the following six components: 1, characterized by consumption of milk and fresh juice, but not packaged juice; 2, by regular soda and other drinks, but not water; 3, by fresh juice and other drinks; 4, by packaged juice, but not regular soda; 5, by water and milk; and 6, by fresh juice. Component 5 was negatively correlated with urine osmolality (P = 0.001) indicating better hydration, whereas component 2 was positively correlated with urine osmolality (P = 0.001). Conclusions A drinking pattern based on water and milk was associated with better hydration, as indicated by lower urine osmolality, whereas drinking regular soda and other drinks but not water was associated with inferior hydration., Author(s): Dimitris Bougatsas [sup.1] , Giannis Arnaoutis [sup.1] , Demosthenes B. Panagiotakos [sup.1] , Adam D. Seal [sup.2] , Evan C. Johnson [sup.3] , Jeanne H. Bottin [sup.4] , Spiridoula [...]

Purpose: The purpose of the present study was to investigate the relationship between weightlifting performance and the rate of force development (RFD), muscle architecture, and body composition in elite Olympic weightlifters. Methods: Six male Olympic weightlifters (age 23.3 [3.4] y, body mass 88.7 [10.2] kg, body height 1.76 [0.07] m, snatch 146.7 [15.4] kg, clean and jerk 179.4 [22.1] kg), all members of the national team, participated in the study. Athletes completed a 16-week periodized training program aiming to maximize their performance at the national competition event. Measurements, including maximal strength (1-repetition maximum) in snatch, clean and jerk, back and front squat, isometric leg press RFD and peak force, countermovement jump, vastus lateralis muscle architecture, and body composition, were performed before and after the training period. Results: Weightlifting performance increased significantly after training (P <.05). Leg press RFD increased only in time windows of 0 to 200 and 0 to 250 milliseconds after training (8.9% [8.5%] and 9.4% [7.7%], respectively, P <.05) while peak force remained unaltered (P <.05). Front squat strength increased significantly (P <.05), while countermovement jump power increased 2.3% (2.1%) (P <.05). No changes were observed for muscle architecture and lean body mass (P >.05). Significant correlations were observed between performance in snatch and clean and jerk with isometric leg press RFD, at all time windows, as well as with lean body mass and squat 1-repetition maximum. Conclusions: These results suggest that regular examination of RFD, lean body mass, and lower extremities' 1-repetition maximum may be useful performance predictors in elite Olympic weightlifters. [ABSTRACT FROM AUTHOR]

The purpose of this article is to assess the hydration status of elite young sailing athletes during World Championship competition. Twelve young, elite, male, Laser Class sailors (age: 15.8 ± 1.1 y, height: 1.74 ± 0.1 m, weight: 65.1 ± 1.5 kg, body fat: 12.5 ± 3.1%, training experience: 7.0 ± 1.2 y) participated in this descriptive study. After three-day baseline bodyweightmeasurements, hydration status was assessed via pre- and post-race body weights, urine-specific gravity, and thirst ratings via a visual analog scale during four consecutive days of racing. Measurements and data collection took place at the same time each racing day, with mean environmental temperature, humidity, and wind speed at 23.0 ± 0.8°C, 64-70%, and 9 ± 1 knots, respectively. Average racing time was 130 ± 9 min. Body weight was significantly decreased following each race-day as compared to prerace values (Day 1: -1.1 ± 0.2, Day 2: -2.5 ± 0.1, Day 3: -2.8 ± 0.1, and Day 4: -3.0 ± 0.1% of body weight; p < 0.05). The participants exhibited dehydration of -2.9 ± 0.2 and -5.8 ± 0.2% of body weight before and after the fourth racing day as compared to the three-day baseline body weight. Urine-specific gravity (pre-post → Day 1: 1.014-1.017; Day 2: 1.019-1.024; Day 3: 1.021-1.026; Day 4: 1.022-1.027) and thirst (pre-post → Day 1: 2.0-5.2; Day 2: 3.2-5.5; Day 3: 3.7-5.7; Day 4: 3.8-6.8) were also progressively and significantly elevated throughout the four days of competition. The data revealed progressive dehydration throughout four consecutive days of racing as indicated by decreased body weight, elevated urine concentration, and high thirst. [ABSTRACT FROM AUTHOR]

Few studies have examined variations in obesity by geographic location in youth and its relation with fitness levels. The present study investigated the association between geographic status (islands versus mainland), excess of body weight and fitness levels among 335.810 schoolchildren (male: 51.3%, 6–18 y, during the school year 2014–2015). Students' anthropometric parameters and fitness levels - accessed via the Euro-fit test - were measured by trained physical education teachers and evaluated according to published norms. Prevalence of overweight (23.0 Vs 21.8%) and obese (10.1 Vs 8.0%) was significantly higher for students living in the islands contrary to their mainland counterparts. A significant difference was also observed for centrally obese children (33.5 Vs 28.2%). Except for speed test.408), in all other four fitness tests, the students from the islands presented significantly lower performance (≤25th percentile of published age- and sex-specific normative values) versus their mainland counterparts. Boys and girls living in the islands had 48% and 37% increased odds of low physical fitness (as a total), respectively, compared to their mainland counterparts. Likewise, children living in islands presented increased odds of being overweight or obese by 19% and 15% in boys and girls, respectively, as compared to those living in the mainland. Increased general and abdominal adiposity have a direct negative impact on students' performance in Physical Fitness tests. Our data highlight the problem of excessive body weight that children living in rural areas, face. [ABSTRACT FROM AUTHOR]

We aimed to model endurance, explosive power, and muscle strength in relation to body mass index (BMI) and physical-fitness tests in Greek children aged 7-10 years old. In the present large epidemiological study, anthropometric measurements and physical-fitness tests (i.e., multistage shuttle run, vertical jump, standing long jump, small ball throw and 30-m sprint) from 141,169 children were analyzed. Age- and sex-specific normative values for physical fitness tests were expressed as tabulated percentiles using the LMS statistical method. The correlation coefficients between BMI and performances were negative and significant for both sexes (p < .01) in all physical-fitness tests. The only exception was a positive correlation between ball throw and BMI (p < .01). Only 2.9% and 4.0% of boys and girls respectively, passed the upper quartiles in all tests. The performance in speed may serve as a predictive factor explaining, at least in part, the performance in aerobic endurance and explosive power in children aged 7-10 years. The presented population-based data for physical-fitness tests revealed that only a small percentage of these children are in the upper quartiles in all tests. Furthermore, the data suggests that speed performance can be used to predict physical fitness. [ABSTRACT FROM AUTHOR]

There is a lack of studies concerning hydration status of young athletes exercising in the heat. Purpose: To assess preexercise hydration status in young soccer players during a summer sports camp and to evaluate body- water balance after soccer training sessions. Methods: Initial hydration status was assessed in 107 young male soccer players (age 11-16 yr) during the 2nd day of the camp. Seventy-two athletes agreed to be monitored during 2 more training sessions (3rd and 5th days of the camp) to calculate dehydration via changes in body weight, while water drinking was allowed ad libitum. Hydration status was assessed via urine specific gravity (USG), urine color, and changes in total body weight. Mean environmental temperature and humidity were 27.2 ± 2 °C and 57% ± 9%, respectively. Results: According to USG values, 95 of 107 of the players were hypohydrated (USG > 1.020) before practice. The prevalence of dehydration observed was maintained on both days, with 95.8% and 97.2% of the players being dehydrated after the training sessions on the 3rd and 5th days, respectively. Despite fluid availability, 54 of the 66 (81.8%) dehydrated players reduced their body weight (-0.35 ± 0.04 kg) as a response to training, while 74.6% (47 out of the 63) further reduced their body weight (-0.22 ± 0.03 kg) after training on the 5th day. Conclusion: Approximately 90% of the young soccer players who began exercising under warm weather conditions were hypohydrated, while drinking ad libitum during practice did not prevent further dehydration in already dehydrated players. [ABSTRACT FROM AUTHOR]

Aim of the study was to investigate the relationship between lower body rate of force development and lean body mass, with competitive shot-put throwing performance in female shot-putters using the linear style. Seven female shot-put athletes (age: 24.4 ± 4.2yrs, body height: 172.8 ± 5.2cm, body mass: 93.3 ± 10.5kg, 4.4 ± 2.0 years of competition experience), who qualified for the final of the shot-put event of the national indoor championship, participated in the study. Three days after the national event, they visited the laboratory to perform maximal isometric leg press for the measurement of the rate of force development (RFD), and maximal countermovement jumps (CMJ), while body composition (dual x-ray absorptiometry) was also evaluated. Shotput performance was recorded from the official results during the national event. Close correlations were found between shot-put performance during competition and RFD between 100-250ms, maximum leg press isometric force, and CMJ power (r: 0.766 - 0.913, p < 0.05). Close correlations were also found between shot-put performance and total (r: 0.932, p < 0.005) and trunk (r: 0.885, p < 0.005) lean body mass (LBM). Lower extremities' LBM was correlated with CMJ max power and RFD between 0-250ms from the onset of muscle contraction (r: 0.834 - 0.905, p < 0.05). These results suggest that monitoring leg press rate of force development, lean body mass and countermovement jumping power may provide important information about performance in female shot-putters who compete with the lineal style. [ABSTRACT FROM AUTHOR]