Many young elite athletes do not meet their daily energy and nutrient requirements. However, little research has been done on why these athletes do not meet their daily needs. The aim was to research the barriers and ...Many young elite athletes do not meet their daily energy and nutrient requirements. However, little research has been done on why these athletes do not meet their daily needs. The aim was to research the barriers and motivators of young Dutch elite athletes to optimize their nutritional intake. Quantitative and qualitative research was conducted among 8 handball and 4 volleyball players at the Dutch National Sports Center (17.2 ± 0.8 years). First, the nutritional intake was tracked through food diaries and analyzed in Nutritics. Thereupon, five semi-structured interviews based on the COM-B model were carried out. The interviews were transcribed and coded. The athletes had a reduced intake of energy, carbohydrates, vitamins A, C, E, D, calcium, potassium, zinc, and iron compared to their requirements. Seven themes for optimizing their nutritional intake emerged in the interviews: needs assessment, practical translation, portion size, lack of time, involvement, individuality, and food distribution. Barriers that the athletes experienced were that they did not know what their total daily nutritional needs were and how this translates into practice. In addition, the portion size at dinner was too small. They also had little time to eat a full meal due to time pressure from training and school. On the other hand, motivators were receiving meal options to translate their needs into practice with a distribution of moments when they need to eat. Covering these topics in nutritional workshops where athletes actively participate with more individual focus, could contribute to the optimization of their nutritional intake.展开更多
This study analyzed the difference between using a downward breaststroke kick and a horizontal breaststroke kick in a sample of world class elite swimmers.We compared average muscle activity of the gluteus maximus,qua...This study analyzed the difference between using a downward breaststroke kick and a horizontal breaststroke kick in a sample of world class elite swimmers.We compared average muscle activity of the gluteus maximus,quadriceps femoris(vastus medialis and rectus femoris),hamstring/long head of the biceps femoris,gastrocnemius medialis,rectus abdominal,and erector spinae when using the downward breaststroke kick technique.We find that when this sample of swimmers utilized the downward breaststroke kick,max speed and velocity per stroke increased,measured by 12,788 EMG samples,where the results are highly correlated to duration of the aerodynamic buoyant force in breaststroke kick technique.The increases in performance observed from measuring the world class elite swimmers is highly correlated to the duration of the kick aerodynamic buoyant force.Among this sample of elite swimmers,the longer a swimmer demonstrates a buoyant force breaststroke kick,the lower the time in a 100 breaststroke.展开更多
Due to the complexity of leadership and its variability across situations,it is suggested that research on leadership should focus on attempts to understand leadership in specific situations or roles,and develop local...Due to the complexity of leadership and its variability across situations,it is suggested that research on leadership should focus on attempts to understand leadership in specific situations or roles,and develop local knowledge about leadership in each situation or role.This paper validates the possibility and importance of building indigenous leadership theories from historical perspective.We demonstrated how to carry out research on indigenous Chinese leadership from a historical perspective by comparative case studies using historical data.Based on the principles of typicalness,representativeness,and comparativeness,we selected six counterparts of political elites in ancient China as comparative cases,which includes Guan Zhong&Shang Yang(organizational reformer),Liu Bang&Xiang Yu(entrepreneur),Li Shimin&Qin Shihuang(intergenerational transition successor),Zhuge Liang&Zeng Guofan(professional manager),Lu Su&Zhang Juzheng(mess-to-order maker),and Zuo Zongtang&Wang Anshi(national dream driver).The paper aims to develop indigenous leadership theory specific to Chinese mental states and culture.展开更多
The fruit-bearing quantities of nut Korean pines (Pinus Koraiensis) of natural stands in Changbai Mountain, Xiaoxing'an Mountain, and Wanda Mountain and of artificial forest in Hegang area of Heilongjiang Province...The fruit-bearing quantities of nut Korean pines (Pinus Koraiensis) of natural stands in Changbai Mountain, Xiaoxing'an Mountain, and Wanda Mountain and of artificial forest in Hegang area of Heilongjiang Province were investigated and measured by seed collection of singletree during 1988–1998. In order to evaluate the elite nut tree of fructification, the characteristics of fructification of Korena pine, including, the fruit-bearing quantity, output of seed, quantity of cone, cone size, seed size, the ratio of null seed by solid seed, seed percentage of cone, rate of the cones infested with pest, and fruit-bearing index, etc., were analyzed with the variance analysis, multiple comparison and stepwise regression to obtain the contribution ratio of each fruit-bearing factor to fruit-bearing quantity. The multiple correlation factors and the partial correlation factors for fruit-bearing quantities of Korean pine were determined for different geographical areas, and the cone length, thousand-grain-weight, and the seed percentage of cone were considered as important indices for selection of elite trees. The method of modified weighted coefficients was adopted to select the elite nut trees of Korean pine. Standards for selecting elite nut trees from the natural stands and artificial forest of Korean pine were established. This study could provde selection method and standard of elite nut trees for setting up seed orchard of Korean Pine.展开更多
文摘Many young elite athletes do not meet their daily energy and nutrient requirements. However, little research has been done on why these athletes do not meet their daily needs. The aim was to research the barriers and motivators of young Dutch elite athletes to optimize their nutritional intake. Quantitative and qualitative research was conducted among 8 handball and 4 volleyball players at the Dutch National Sports Center (17.2 ± 0.8 years). First, the nutritional intake was tracked through food diaries and analyzed in Nutritics. Thereupon, five semi-structured interviews based on the COM-B model were carried out. The interviews were transcribed and coded. The athletes had a reduced intake of energy, carbohydrates, vitamins A, C, E, D, calcium, potassium, zinc, and iron compared to their requirements. Seven themes for optimizing their nutritional intake emerged in the interviews: needs assessment, practical translation, portion size, lack of time, involvement, individuality, and food distribution. Barriers that the athletes experienced were that they did not know what their total daily nutritional needs were and how this translates into practice. In addition, the portion size at dinner was too small. They also had little time to eat a full meal due to time pressure from training and school. On the other hand, motivators were receiving meal options to translate their needs into practice with a distribution of moments when they need to eat. Covering these topics in nutritional workshops where athletes actively participate with more individual focus, could contribute to the optimization of their nutritional intake.
文摘This study analyzed the difference between using a downward breaststroke kick and a horizontal breaststroke kick in a sample of world class elite swimmers.We compared average muscle activity of the gluteus maximus,quadriceps femoris(vastus medialis and rectus femoris),hamstring/long head of the biceps femoris,gastrocnemius medialis,rectus abdominal,and erector spinae when using the downward breaststroke kick technique.We find that when this sample of swimmers utilized the downward breaststroke kick,max speed and velocity per stroke increased,measured by 12,788 EMG samples,where the results are highly correlated to duration of the aerodynamic buoyant force in breaststroke kick technique.The increases in performance observed from measuring the world class elite swimmers is highly correlated to the duration of the kick aerodynamic buoyant force.Among this sample of elite swimmers,the longer a swimmer demonstrates a buoyant force breaststroke kick,the lower the time in a 100 breaststroke.
文摘Due to the complexity of leadership and its variability across situations,it is suggested that research on leadership should focus on attempts to understand leadership in specific situations or roles,and develop local knowledge about leadership in each situation or role.This paper validates the possibility and importance of building indigenous leadership theories from historical perspective.We demonstrated how to carry out research on indigenous Chinese leadership from a historical perspective by comparative case studies using historical data.Based on the principles of typicalness,representativeness,and comparativeness,we selected six counterparts of political elites in ancient China as comparative cases,which includes Guan Zhong&Shang Yang(organizational reformer),Liu Bang&Xiang Yu(entrepreneur),Li Shimin&Qin Shihuang(intergenerational transition successor),Zhuge Liang&Zeng Guofan(professional manager),Lu Su&Zhang Juzheng(mess-to-order maker),and Zuo Zongtang&Wang Anshi(national dream driver).The paper aims to develop indigenous leadership theory specific to Chinese mental states and culture.
基金Sciences and Technology Office of Heilongjiang Province (a grant G99B5-10).
文摘The fruit-bearing quantities of nut Korean pines (Pinus Koraiensis) of natural stands in Changbai Mountain, Xiaoxing'an Mountain, and Wanda Mountain and of artificial forest in Hegang area of Heilongjiang Province were investigated and measured by seed collection of singletree during 1988–1998. In order to evaluate the elite nut tree of fructification, the characteristics of fructification of Korena pine, including, the fruit-bearing quantity, output of seed, quantity of cone, cone size, seed size, the ratio of null seed by solid seed, seed percentage of cone, rate of the cones infested with pest, and fruit-bearing index, etc., were analyzed with the variance analysis, multiple comparison and stepwise regression to obtain the contribution ratio of each fruit-bearing factor to fruit-bearing quantity. The multiple correlation factors and the partial correlation factors for fruit-bearing quantities of Korean pine were determined for different geographical areas, and the cone length, thousand-grain-weight, and the seed percentage of cone were considered as important indices for selection of elite trees. The method of modified weighted coefficients was adopted to select the elite nut trees of Korean pine. Standards for selecting elite nut trees from the natural stands and artificial forest of Korean pine were established. This study could provde selection method and standard of elite nut trees for setting up seed orchard of Korean Pine.
