ObjectiveThe critical period that is closely related with the performance of the strength,endurance, speed, quality and the special technical development is adolescence inswimming. Therefore, it is very important that mastering special ability of adolescentswimmers and developing targeted training program for young swimmers to achievesuccess in the international games. Due to limitations on the technical conditions andother reasons, the current domestic evaluation method of swimming exercise specialability is single, it is difficult to find the real reason of limitations on improvingathletic performance, which provide limited guidance to the training. The foreignresearches are not very perfect because of the lack of systematic research. In this study,various advanced scientific research equipment in swimming flume laboratory,establishing test methods on physical stamina are utilized and skills in adolescentfreestyle swimmers are executed. Longitudinal observation on the part of the specialability before and after the swimmers training phase is done in order to make theevaluation of the effect of exercise training more systematic and accurate and havemore guidance value for sports training, which is meaningful exploration in selectionof freestyle swimmers. Through this study, we will provide the special ability test andmonitoring methods systematically for swimmers to identify the maximumproficiency and coaches to arrange scientific training, which will effectively ensurethat the swimmers will develop towards the expected goals.MethodsThirty six adolescent freestyle swimmers (male10, female26) in Shanghai areselected as object in this study, and all of them reach the national one-level.Swimmer’s VO2max is tested by swimming flume incremental test methods, andthe lactate threshold for athletes is tested by Kindermann method(male7, female8).Swimmer’s aerobic capacity and maximum capacity are tested by use of swimmingflume, and then anaerobic capacity of athletes is calculated(male3, female3). Specialstrength of athletes is tested by simple swimming strength tester and swimmingflume(female7). Technology parameters on the athletes and the energy consumptionare tested by the use of three line system test methods(female8), and then methods ofcontroling for adolescent swimmer’s aerobic capacity, anaerobic capacity, specificstrength and technical economy are gradually established.Results1. Testing methods and their application on aerobic metabolic capability of eliteadolescent freestyle swimmers in Shanghai1.1Establishing of VO2max test methods in adolescent freestyle swimmers The test time in male swimmers and female swimmers are more than8min, butthere are no significant differences between the two groups (P>0.05). The max heartrate in male swimmers and female swimmers are more than180, and there are nosignificant differences between the two groups (P>0.05). The immediate lactic acidafter test in male swimmersand female swimmers are more than6mmol/L, and thereare no significant differences between the two groups (P>0.05).There are nosignificanct differences between the two groups in relative VO2max(P>0.05).Respiratory quotient in male swimmers and female swimmers are more than1.1, butthere are no significant differences between the two groups (P>0.05).1.2Study of lactate threshold of elite adolescent freestyle swimmers in ShanghaiLactate threshold in male swimmers is3.57±0.43mmol/L and that in femalteswimmers is3.1±0.38mmol/L, and there are significant differences between the twogroups(P<0.05).1.3Study of changes in aerobic metabolic capacity monitoring before and after thewinter training of the elite adolescent freestyle swimmers in ShanghaiThe result of VO2max intensity training in male swimmers is increased by0.35,there are significant differences before and after training (P<0.01). The results ofanaerobic threshold intensity training in female swimmers is increased by0.41seconds and VO2max intensity training in female swimmers is increased by0.87, andthere are significant differences before and after training(P<0.01). Lactate threshold infemale swimmers is increased by0.09mmol/L, and there are significant differencesbefore and after training(P<0.05).After the winter training, VO2max in male swimmers and female swimmers areindividually increased by2.46%(P>0.05) and6.68%(P<0.05), and relative VO2maxare individually increased by2.41%(P>0.05) and6.43%(P<0.05). After the wintertraining, max swimming duration in female swimmer is significantly increased(10.35%, P<0.05). Ventilatory threshold up time in male swimmer and femaleswimmer are individually increased by22.03%and20.88%, and there are significantdifferences between before and after training(P <0.05).2. Testing methods and their application on anaerobic metabolic capability ofelite adolescent freestyle swimmers in ShanghaiThere are great differences in anaerobic capacity, and the highest is18.36ml/(min*kg) and the lowest is2.56ml/(min*kg), and the mean is12.04ml/(min*kg).The highest of maximum capacity is79.17ml/(min*kg) and the lowest is61.59ml/(min*kg), and the mean is71.60ml/(min*kg). The highest of max lactate is11.48mmol/L and the lowest is7.67mmol/L, and the mean is9.10mmol/L.3. Testing methods and their application on special strength of elite adolescentfreestyle swimmers in ShanghaiThe ratios of the pulling, kicking, swimming force in the first10seconds and thetotal force of45seconds total force are0.248,0.273,0.27indibidually; and the ratios of the pulling, kicking, swimming force in the last10seconds of total force are0.203,0.18,0.187individually; the ratios of the pulling, kicking, swimming force in the last10seconds and the last10seconds are1.22,1.56,1.45individually. The maximumratio of total kicking and pulling force and swimming force is1.33, and the minimumratio is1.17.The swimming distance of pulling force in swimmers is14.84m, and themobile distance of kicking force is15.27m, and the mobile distance of swimmingforce is19.02m. The increasing time of pulling is65.38s, and the increasing time ofkicking is47.37s, and the increasing time of swimming is67.36s.There is a strong correlation between results of50m freestyle and the pullingforce in the first10seconds and there is statistical significance(P<0.05). There is acorrelation between results of50m freestyle and the kicking force in the first10seconds, but there is no statistical significance(P>0.05). There is a strong correlationbetween results of50m freestyle and the swimming force in the first10seconds, butthere is no statistical significance(P>0.05). There is a correlation between results of200m freestyle and the pulling force of45seconds and there is no statisticalsignificance(P>0.05). There is a strong correlation between results of50m freestyleand the pulling speed force in the flume, but there is no statistical significance(P>0.05). There is a strong correlation between results of50m freestyle and theswimming speed force in the flume, and there is statistical significance. There is astrong correlation between results of200m freestyle and the increasing pulling forcein the flume, and there is statistical significance. There is a strong correlation betweenresults of200m freestyle and the increasing swimming force in the flume, and there isstatistical significance.4. Testing methods and their application on technical modification and energycost economy of elite adolescent freestyle swimmers in ShanghaiAfter10months of training, the stroke frequency in the second test at the samevelocity is lower than that in the first test, and there is significant difference betweentwo tests (P<0.01). The stroke length and technical index in the second test is higherthan that in the first test, and there is significant difference between two tests (P<0.01).T2phase and T2+T3phase in the second test is increased compared with that in thefirst test, and the difference is significant (P<0.05). At speeds of1.16m/s,1.20m/s and1.24m/s, numerical values of oxygen uptake, ratios of oxygen uptake and bodyweight, ratios of oxygen uptake and body surface area and ratios of oxygen uptakeand the product of body weight and body surface area in the second test are lowerthan that in the first test, and the differences are significant (P<0.01). Ratios ofoxygen uptake and body weight, ratios of oxygen uptake and body surface area andratios of oxygen uptake and the product of body weight and body surface area in thesecond test are lower than that in the first test, and the differences are significant(P<0.01). At the highest speed in the second test, numerical values of oxygen uptake,ratios of oxygen uptake and body weight, ratios of oxygen uptake and body surfacearea and ratios of oxygen uptake and the product of body weight and body surfacearea in the second test are increased compared with that in the first test, and thedifferences are significant (P<0.01). Among five comparable speeds, numerical values of oxygen uptake at speeds of1.16m/s,1.20m/s and1.24m/s in the second test arelower than that in the first test, and the differences are significant (P<0.01).Conclusions and recommendations1. When VO2max in s is examined in swimming flume, the test program usingstarting speed of1.20m/s and1.16m/s and load mode of the0.04m/s in per minuteincrements is suitable for adolscent freestyle swimmers, and the test results can reflectthe level of aerobic capacity.During the winter training, aerobic capacity in femaleswimmers is been significantly improved, but there is no significant change in themale swimmers, which shows that methods and training arrangement in the wintertraining play a limited role on aerobic capacity.2. There is individual difference in anaerobic capacity of young swimmers, weakpoints can be clearly understood through the anaerobic capacity, aerobic capacity andmaximum capacity tests, which can provide meaningful reference for the coaches tomaking the individual training plan and select swimmers.3. A good coordination of pulling and kicking will play a large role on improvingthe performance. Correlation between special strength of adolescent freestyleswimmer and results in50m and200m shows that there is a strong correlationbetween special strength of adolescent freestyle swimmer and performance. Thecombination of the specific performance and results of specific strength test will givebetter guidance for coaches.4. After ten months training, changes of structure of the technical movement inadolescent Freestyle swimmer consist in T2phase and T2+T3phase. Movement cycleis prolonged and stroke length is increased. With the changes of technology, energyconsumption of adolescent freestyle swimmer is decreased and exercise time isincreased, and exercise ability is improved. When technical is changed in freestyleswimmers, effects on energy consumption is much higher than the influence of height,weight and other factors. So adolescent freestyle swimmers should pay specialattention to strengthening the technical training, and regular tests in technology andenergy consumption can better grasp the swimmers’ changes of ability. |