Erfolge mittels Rudererergometer und anaerobe leistungsmöglichkeit bei den Ruderern-studenten

The aim of the study presented was to assess the relationships between the 6-minute "all-out" rowing ergometer test with physical performance indices in college rowers. Ten male rowers (21.60+4.20 yrs; 186,90+5.64 cm; 84.10+6.59 kg; %body fat: 9.62+2.81%) performed a 6-minute "all-out" rowing ergometer test on a rowing ergometer (Concept II, USA) at the first measurement session. In addition, a graded exercise test at the intensities of 150, 200 and 250 W (6-minutes each) and a maximal 5x1 minute interval test were performed at separate measurement sessions. The heart rate (HR) was recorded at the end of each load during a graded exercise test. The individual physical working capacity (PWC) of the rowers was calculated at the maximum of HR recorded during a 6-minute "all-out" test. Blood samples for lactate (LA) determination were obtained from the fingertip before and immediately after each bout of exercise. The anaerobic threshold (AT) indices were determined by interpolation from the relationships between the LA concentration and the respective variable at a LA concentration of 4.0 mmol/l. The LA concentration in the blood was also determined before, immediately after and after 3 minutes and 5 minutes of recovery of the maximal 5 x 1 minute interval test. Significant correlations (p<0.05) were observed between the AT (W) and power (r=0.56) and the covered distance (r=0.55) of a 6-minute "all-out" test. In addition, the power and distance covered of the 6-minute "all-out" test were significantly related to the covered distance and power of all five trials of the maximum interval test (r=0.64-0.77). The stepwise multiple interval test indicated that the power of a 6-minute "all-out" test was explained by the mean power of a maximal 5 x 1 minute interval test at 82.75% (R2). In conclusion, the results of our study suggest that our proposed interval test has a high diagnostic value in the assessment of the anaerobic work capacity of rowers.Das Ziel dieser Untersuchung war, die Zusammenhange zwischen 6-Minuten Leistungstest mittels eines Rudererergometers und Indexen der körperlichen Leistungsmöglichkeit von Ruderern-Studenten zu erstellen. Zehn männliche Ruderer (21.60+/-4.20 Jahre; 186,90+/-5,64cm; 84,10+/-6,59kg; 9,62+/-2,81% Fettgewebe) wurden dem 6-Minuten Leistungstest am Rudererergometer (Concept II, USA) in der ersten Messung unterzogen. Zusätzlich wurden der progressive Belastungstest mit den Werten 150, 200 und 250 W (je 6 Minuten) und der Intervall-Leistungstest in der Zeitspanne von 5x1 Minute in abgesonderten Messungen durchgeführt. Die Herzfrequenz (Heart Rate - HR) wurde in der Endphase jeder Belastung des Stufentestes gemessen. Persönliche körperliche Arbeitsleistung (PWC - engl. physical working capacity) der Ruderer wurde nach maximal gemessener Herzfrequenz in der Zeitspanne des 6-Minuten Leistungtestes errechnet. Aus der Fingerkuppe wurden vor und nach jeder Leistung die Blutproben zur Feststellung des Milchsäurespiegels (LA) entnommen. Die Indexe der anaeroben Schwelle (anaerobic threshold - AT) wurden nach der vorgenommenen Interpolation der Wechselbeziehung zwischen dem LA-Spiegel und der entsprechenden Variable mit der Konzentration von 4,0 mmol/ festgestellt. Der LA-Spiegel wurde im Blut vorher, anschließend, 3 wie auch 5 Minuten nach dem Intervall-Leistungstest 5x1 gemessen. Es wurde eine bedeutende Wechselbeziehung (p<0,05) zwischen der anaeroben Schwelle (W) und dem Kraftaufwand (r=0,56) einerseits und der zurückgelegten Entfernung (r=0,55) in den Zeitspannen des Leistungtestes festgestellt. Der Kraftaufwand und die zurückgelegten Entfernung im Laufe des Leistungtestes hingen auch bedeutend von der zurückgelegten Entfernung und dem Kraftaufwandin allen fünf Zeitspannen des Intervall- Leistungtestes (r=0,64-0,77) ab, Der wicderholende Intervall-Test mit progressiver Belastung ‘beweist, dass sich der 82,75% (R2) Kraftaufwand, gemessen in 6-Minuten Leistungtest, über arithmetisches Mittel vom Kraftaufwand, gemessen im Leistungtest mit Intervallen von 5x1 Minute erklären lasst. Wir schlussfolgern, dass die Ergebnisse unserer Untersuchung darauf hinweisen, wie hoch der diagnostische Wert des vorgeschlagenen Intervall-Leistungtests bei der Einschätzung von Arbeitsleistung der Ruderer ist

Adiponectin and osteocalcin responses to rowing exercise, and the relationship to substrate oxidation in female rowers

This study investigated the effects of acute exercise and menstrual phase on adiponectin and osteocalcin concentrations, and the possible role of these biomarkers in exercise-induced substrate oxidation in rowers. Thirteen female rowers (19.3 ± 2.3 years; height: 172.7 ± 3.9 cm; body mass: 66.5 ± 7.9 kg) performed 1-h rowing ergometer exercise at 70% of maximal oxygen consumption (VO2max) during follicular phase and luteal phase of the menstrual cycle. Oxygen consumption (VO2), total energy expenditure (EE), carbohydrate EE, and lipid EE were assessed during the exercise. Venous blood samples were collected before and after ergometer exercise. No differences (p > 0.05) were observed in substrate oxidation values during exercise across menstrual cycle. Exercise resulted in an acute rise in osteocalcin and no changes in adiponectin at both menstrual cycle phases. Adiponectin and osteocalcin were not related across phase or time (r  0.05). Post-exercise adiponectin was related (p 2 (r = 0.459) and total EE rate (r = 0.598), while post-exercise osteocalcin was correlated (p < 0.05) with mean total (r = 0.411) and lipid (r = 0.557) EE rates. In conclusion, menstrual cycle phase had no effect on substrate oxidation, and adiponectin and osteocalcin responses to acute exercise. It appears that adiponectin and osteocalcin may serve as signals for metabolic reaction to the energy cost of the acute exercise in female rowers

Anthropometric comparison between young Estonian and Chinese swimmers

Due to the progressive lowering of the age of peak performance among swimmers, it became important to better understand the factors influencing performance in prepuberal boys and girls. Aim of this study is to compare two different racial/ethnic groups of young swimmers, one from Nord-Europe, Estonia (Tartuma Region), and the other from China (Shanghai District) in order to assess existing differences in respect to body dimension, body fat, technical parameters of swimming performance and maximum lactate production. 26 Estonian and 7 Chinese female and 25 Estonian and 10 Chinese male, from two swimming schools, took part in the study. Anthropometric parameters were measured in accord with ISAK guidelines. BMI, Stroke Index, Stroke Length, mean velocity on a 200 m freestyle all out, and blood lactate after three minutes were measured. Significant differences exist in anthropometry between Nord-European and Asian young swimmers. These differences are more pronounced in female, with higher fat tissue in Nordic girls. Leg lengths are different between Chinese and Estonian girls having the Estonian longer legs. Hands lengths are different both in male and in female subjects. Being the Chinese groups of higher level of performance (higher mean velocity in the 200 m freestyle, such differences seems not to be as major determinants of the performance, also if they are often indicated as determinants of buoyancy and stroke efficiency

Report Card grades on the physical activity of children and youth comparing 30 very high Human Development Index countries

Background: To better understand the childhood physical inactivity crisis, Report Cards on physical activity of children and youth were prepared concurrently in 30 very high Human Development Index countries. The aim of this article was to present, describe, and compare the findings from these Report Cards. Methods: The Report Cards were developed using a harmonized process for data gathering, assessing, and assigning grades to 10 common physical activity indicators. Descriptive statistics were calculated after converting letter grades to interval variables, and correlational analyses between the 10 common indicators were performed using Spearman's rank correlation coefficients. Results: A matrix of 300 grades was obtained with substantial variations within and between countries. Low grades were observed for behavioral indicators, and higher grades were observed for sources of influence indicators, indicating a disconnect between supports and desired behaviors. Conclusion: This analysis summarizes the level and context of the physical activity of children and youth among very high Human Development Index countries, and provides additional evidence that the situation regarding physical activity in children and youth is very concerning. Unless a major shift to a more active lifestyle happens soon, a high rate of noncommunicable diseases can be anticipated when this generation of children reaches adulthood.</p

Report Card Grades on the Physical Activity of Children and Youth Comparing 30 Very High Human Development Index Countries

BACKGROUND: To better understand the childhood physical inactivity crisis, Report Cards on physical activity of children and youth were prepared concurrently in 30 very high Human Development Index countries. The aim of this article was to present, describe, and compare the findings from these Report Cards. METHODS: The Report Cards were developed using a harmonized process for data gathering, assessing, and assigning grades to 10 common physical activity indicators. Descriptive statistics were calculated after converting letter grades to interval variables, and correlational analyses between the 10 common indicators were performed using Spearman's rank correlation coefficients. RESULTS: A matrix of 300 grades was obtained with substantial variations within and between countries. Low grades were observed for behavioral indicators, and higher grades were observed for sources of influence indicators, indicating a disconnect between supports and desired behaviors. CONCLUSION: This analysis summarizes the level and context of the physical activity of children and youth among very high Human Development Index countries, and provides additional evidence that the situation regarding physical activity in children and youth is very concerning. Unless a major shift to a more active lifestyle happens soon, a high rate of noncommunicable diseases can be anticipated when this generation of children reaches adulthood.</p

Vitamin C and E treatment blunts sprint interval training–induced changes in inflammatory mediator-, calcium-, and mitochondria-related signaling in recreationally active elderly humans

Sprint interval training (SIT) has emerged as a time-efficient training regimen for young individuals. Here, we studied whether SIT is effective also in elderly individuals and whether the training response was affected by treatment with the antioxidants vitamin C and E. Recreationally active elderly (mean age 65) men received either vitamin C (1 g/day) and vitamin E (235 mg/day) or placebo. Training consisted of nine SIT sessions (three sessions/week for three weeks of 4–6 repetitions of 30-s all-out cycling sprints) interposed by 4 min rest. Vastus lateralis muscle biopsies were taken before, 1 h after, and 24 h after the first and last SIT sessions. At the end of the three weeks of training, SIT-induced changes in relative mRNA expression of reactive oxygen/nitrogen species (ROS)and mitochondria-related proteins, inflammatory mediators, and the sarcoplasmic reticulum Ca2+ channel, the ryanodine receptor 1 (RyR1), were blunted in the vitamin treated group. Western blots frequently showed a major (>50%) decrease in the full-length expression of RyR1 24 h after SIT sessions; in the trained state, vitamin treatment seemed to provide protection against this severe RyR1 modification. Power at exhaustion during an incremental cycling test was increased by ~5% at the end of the training period, whereas maximal oxygen uptake remained unchanged; vitamin treatment did not affect these measures. In conclusion, treatment with the antioxidants vitamin C and E blunts SIT-induced cellular signaling in skeletal muscle of elderly individuals, while the present training regimen was too short or too intense for the changes in signaling to be translated into a clear-cut change in physical performance

Global matrix 2.0:Report card grades on the physical activity of children and youth comparing 38 countries

The Active Healthy Kids Global Alliance organized the concurrent preparation of Report Cards on the physical activity of children and youth in 38 countries from 6 continents (representing 60% of the world's population). Nine common indicators were used (Overall Physical Activity, Organized Sport Participation, Active Play, Active Transportation, Sedentary Behavior, Family and Peers, School, Community and the Built Environment, and Government Strategies and Investments), and all Report Cards were generated through a harmonized development process and a standardized grading framework (from A = excellent, to F = failing). The 38 Report Cards were presented at the International Congress on Physical Activity and Public Health in Bangkok, Thailand on November 16, 2016. The consolidated findings are summarized in the form of a Global Matrix demonstrating substantial variation in grades both within and across countries. Countries that lead in certain indicators often lag in others. Average grades for both Overall Physical Activity and Sedentary Behavior around the world are D (low/poor). In contrast, the average grade for indicators related to supports for physical activity was C. Lower-income countries generally had better grades on Overall Physical Activity, Active Transportation, and Sedentary Behaviors compared with higher-income countries, yet worse grades for supports from Family and Peers, Community and the Built Environment, and Government Strategies and Investments. Average grades for all indicators combined were highest (best) in Denmark, Slovenia, and the Netherlands. Many surveillance and research gaps were apparent, especially for the Active Play and Family and Peers indicators. International cooperation and cross-fertilization is encouraged to address existing challenges, understand underlying determinants, conceive innovative solutions, and mitigate the global childhood inactivity crisis. The paradox of higher physical activity and lower sedentary behavior in countries reporting poorer infrastructure, and lower physical activity and higher sedentary behavior in countries reporting better infrastructure, suggests that autonomy to play, travel, or chore requirements and/or fewer attractive sedentary pursuits, rather than infrastructure and structured activities, may facilitate higher levels of physical activity.</p

Global Matrix 3.0 Physical Activity Report Card Grades for Children and Youth:Results and Analysis From 49 Countries

BACKGROUND: Accumulating sufficient moderate to vigorous physical activity is recognized as a key determinant of physical, physiological, developmental, mental, cognitive, and social health among children and youth (aged 5-17 y). The Global Matrix 3.0 of Report Card grades on physical activity was developed to achieve a better understanding of the global variation in child and youth physical activity and associated supports. METHODS: Work groups from 49 countries followed harmonized procedures to develop their Report Cards by grading 10 common indicators using the best available data. The participating countries were divided into 3 categories using the United Nations' human development index (HDI) classification (low or medium, high, and very high HDI). RESULTS: A total of 490 grades, including 369 letter grades and 121 incomplete grades, were assigned by the 49 work groups. Overall, an average grade of "C-," "D+," and "C-" was obtained for the low and medium HDI countries, high HDI countries, and very high HDI countries, respectively. CONCLUSIONS: The present study provides rich new evidence showing that the situation regarding the physical activity of children and youth is a concern worldwide. Strategic public investments to implement effective interventions to increase physical activity opportunities are needed.</p

Regression models for near-infrared measurement of subcutaneous adipose tissue thickness

Obesity is often associated with the risks of diabetes and cardiovascular disease, and there is a need to measure subcutaneous adipose tissue (SAT) thickness for acquiring the distribution of body fat. The present study aimed to develop and evaluate different model-based methods for SAT thickness measurement using an SATmeter developed in our laboratory. Near-infrared signals backscattered from the body surfaces from 40 subjects at 20 body sites each were recorded. Linear regression (LR) and support vector regression (SVR) models were established to predict SAT thickness on different body sites. The measurement accuracy was evaluated by ultrasound, and compared with results from a mechanical skinfold caliper (MSC) and a body composition balance monitor (BCBM). The results showed that both LR- and SVR-based measurement produced better accuracy than MSC and BCBM. It was also concluded that by using regression models specifically designed for certain parts of human body, higher measurement accuracy could be achieved than using a general model for the whole body. Our results demonstrated that the SATmeter is a feasible method, which can be applied at home and in the community due to its portability and convenience